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2f3ibc | Glowing metals from the photoelectric effect? | I've been trying to understand what my textbook is saying about how the photoelectric effect explains the observed glowing of hot metals. I can understand that once photons hitting the metal reach an energy greater than or equal to the work function, the metal emits electrons. My question is: why does this correspond to the metal glowing (and glowing different colors at higher temps)? If photoelectrons, and not photons, are being emitted, why does this produce light at all? | askscience | http://www.reddit.com/r/askscience/comments/2f3ibc/glowing_metals_from_the_photoelectric_effect/ | {
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"My guess is that the textbook is trying to say that both effects are related to the quantization of light.\n\nThe blackbody catastrophe was averted by quantizing the photon (in other words by postulating that photons are physical particles), and the photoelectric effect can most simply be explained by the quantization of the photon as well.\n\nSo yes, the photoelectric effect gave strong evidence of the existence of the photon, which allowed physicists to explain blackbody radiation.\n\nThe photoelectric effect is not what causes metals to glow.",
"I'm happy to be proved wrong, but that sounds completely incorrect - hot objects emit due to [black body radiation](_URL_0_), which is caused by the acceleration of electrons that are moving due to the thermal energy in the material. If it was the photoelectric effect, you would expect there to be a definite cut-off in the point that a metal glows, and that different metals would start to glow at different temperatures, neither of which occurs. Also, using the term \"photoelectron\" would imply that you would need to shine a light on the hot metal to make it glow, but it would quite happily glow in a dark room!"
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3yuyn1 | What caused the Kingdom of the Lombards to go from being stable to being conquered in a short span of time? | From what I hear, the Lombards were as Romanized as barbarians could get and had a stable if decentralized system of government. What caused them to go from being fairly powerful to falling to Charlemagne in a short span of time? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/3yuyn1/what_caused_the_kingdom_of_the_lombards_to_go/ | {
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"You might be thinking of the Ostrogoths and the first Kingdom of Italy. The Lombards are the gold standard of not having their shit together, but not all of it was their fault. \n\nAlthough the Ostrogoths had been given lands in Pannonia in exchange for the defense of the upper Danube, the eastern emperor Zeno came to the conclusion that the Ostrogoths were more trouble than they were worth (fighting with him, fighting with each other, and in a general sense just being another nuisance to deal with) so he convinced their King Theodoric to go conquer Italy. This way, they would stop annoying him, and he could also get rid of Odoacer, another potential opponent.\n\nWho was Odoacer? Flavius Odoacer, the de facto leader of the Foederati or ethnic \"Barbarians\" fighting for Rome (who by now made up most of the army) had deposed Romulus Augustulus when the emperor lost the majority of the army's favor (this was no cakewalk. Odoacer had to fight several pitched battles against armies commanded by Romulus' father and uncle). After coming to power, Odoacer openly admitted that although he might rule Italy, he was powerless beyond the alps, and consequentially didn't call himself Emperor. Instead, he sent the imperial paraphernalia to Constantinople and asked to be recognized as \"Consul\". Odoacer kept all of the functions of the Roman Administration in Italy intact, although there was a big political upheaval, there wasn't much of a cultural upheaval (Flavius Odoacer himself was so romanized historians aren't sure which \"Barbarian\" ethnic group he belonged to).\n\nOdoacer initially played lip service to the previous emperor Julius Nepos (whom Romulus' father had deposed), even minting coinage in his name, but may have been involved in the plot whereby he was murdered. Regardless, after the murder of Julius Nepos, Odoacer asked to be given the title of Patrician by the Eastern Emperor, and be recognized as the ruler of Italy under the wing of a single Roman Emperor in Costantinople.\n\nWhen Zeno sent Theodoric on his mission, he could afford to lose Theodoric's army as the bulk of soldiers in the eastern empire were still \"Romans\", as the large recruiting grounds of Anatolia and Armenia were not yet subject do destabilization (using the word \"Romans\" as they themselves would have: to denote citizens of the empire).\n\nTheodoric the Amal, King of the Ostrogoths, had been raised in Constantinople. His had lived within the Eastern Empire's borders for centuries. When Theodoric defeated Odoacer and set up the first Kingdom of Italy, he did his utmost to further maintain the Roman institutions, law, and judicial system. However, he did not rule from Rome, rather, he ruled from Ravenna, seaside city conveniently defended by swampy surroundings, and easily supplied by ship.\n\nSo here we are, soon after the \"Fall\" of Rome, the first Kingdom of Italy was established as a client state of Costantinople. Including Odoacer's rule, we can say that the First Kingdom of Italy lasted between 476 and 553 as a political entity no less stable (if not slightly more stable) than the late Roman Empire. Why did this kingdom end? Justinian decided to reconquer Italy. And he did. \n\nHowever, under Justinian we start to see signs of the Byzantine Empire's chronic manpower problem, and consequentially lost Italy in less than a generation. Although Justinian was definitely a great wartime politician (who was particularly good at picking the right man for the right job), his conquests stretched Byzantium's resources too far, and even sympathetic chronicles criticize him for being unable to defend what he conquered.\n\nThus, the sparsely defended Italian lands were easy prey for one of the last great \"Barbarian\" migrations: that of the Lombards. [The Lombards would contest Italy nearly continuously with the Byzantines from the 6th to the 8th centuries](_URL_1_). The Lombards moved into the Northern Italian Plains with relative ease, while the Byzantines would hold onto the Pentapolis (the five cities along the eastern coast of Italy near the mouth of the River Po defended by swamps and easily supplied by the sea), the city of Rome and its surroundings, and the easily-reachable Calabria and Puglia regions of Southern Italy.\n\n Between founding the second Kingdom of Italy in 568 and Charlemagne's conquest nearly two hundred years later in 774, the story of the Kingdom of Italy was one of near-continuous warfare with the Eastern Empire. The Lombards \"Went Native\" very rapidly imitating the Roman Imperial customs, establishing Mediolanum (modern Milan) as their capital. They subdivided Italy into various feudal subdivisions. Had things gone differently, perhaps Italy would have survived as a medieval state, and centralized as the rest of Europe did over the course of the renaissance. As those bizarre historical turns of events would have it, the Kingdom of Italy would again be dismantled just when the [Lombard King Desiderious (d. 786) got very close to finally kicking the Byzantines out of Italy](_URL_0_). A successful offensive saw the encirclement of the Pentapolis (that to this day are called \"Romagna\" since the Byzantines were the last \"Romans\" to leave) which allowed Desiderious to march south against Rome unopposed. With the Byzantine army cornered in the Pentapolis and fearing a loss of independence for the bishop of Rome, who had been pretty much guaranteed a free hand to rule the \"Duchy of Rome\" (modern Lazio) in exchange for nominal Byzantine rule and military access, Pope Adrian cried \"Uncle\", excommunicated Desiderius, and asked Charlemagne to come to his aid. Charlemagne, even though he was busy conquering what would later become Germany, was immediately flattered and marched for Italy.\n\nCharlemagne marched down from Germany in two columns, one under his personal command taking a westerly route, through the Valley of Susa, and another under his uncle, Bernard, through the Valley of Aosta.\nAn ancient system of walls called the \"Lombard Locks\" (Chiuse Lombarde) sealed off the valley of Susa, and defenses personally commanded by King Desiderius held fast against Charlemagne's assault. However, the Valley of Aosta was guarded by Desiderius' son, Adelchi, who had been entrusted with a much smaller force. Pushed back by the enemy at Ivrea, Adelchi was forced into a disorderly retreat. Desiderius withdrew to avoid encirclement, and barricaded himself in the ancient fortress of Pavia, while Adelchi withdrew all the way to Verona. Soon, Desiderius capitulated and would spend the rest of his days in a Belgian monastery; Charlemagne was crowned king of Italy, and Adelchi fled to Costantinople (which, in adherence to the principle, \"The enemy of my enemy is my friend\" saw the Byzantine emperor welcome the deposed prince now that Charlemagne was claiming the title \"King of the Romans\").\n\nBut Charlemagne, although crowned \"King of Italy\" had gone no farther south than Rome; he still had to subjugate the other half of the Italian peninsula. Or did he? Seeing Charlemagne and his army at the gates of Salerno, Duke Arechi of Benevento, a powerful and fiercely loyal vassal of the deposed King of Italy (he had married Desiderius' daughter) came to an agreement with Charlemagne. Sending his son Grimolado as a hostage to Charlemagne's court, he secured the right to continue ruling as Duke in southern Italy; and was even elevated to the rank of Prince.\n\nOn the death of his father, Grimolado was allowed to return to Benevento to claim the throne, on the condition that he mint coinage in the name of the Emperor, and demolish the fortifications that dotted Southern Italy. On his arrival, Grimolado immediately began strengthening the fortifications at Benevento and Salerno. Having made his intentions clear to the Carolingans, he then constructed a church dedicated to St. Sophia in Benevento; a direct challenge to the Byzantine empire, just in case they were harboring any thoughts of subjugating him. It looked like the Duchy of Benevento was independent and planning to stay that way.\n\nThe next hundred years would mark the ascent of the Principality of Benevento, and perhaps of Lombard culture as a whole; marked by the monuments constructed in Benevento would lead it to be called, \"The Second Pavia\" (which had been the capital of the previous Kingdom of Italy), and the great wealth of the city of Salerno, which became major mediterranean entrepôt, and become home to a renowned school of Medicine. Successive aggressions, both by Charlemagne's successor Ludovic and his vassals in Italy were successfully repealed, either by force of arms or diplomacy. However, instability would be a hallmark of the principality; as successive invasions by the Byzantine Empire would again reclaim the regions of Calabria and Puglia, while dynastic infighting would split the kingdom three ways by the mid 9th century; the Duchy of Benevento, the Duchy of Salerno, and the Republic of Amalfi (ironically, each capital is within an hour's drive of each other, although the individual territories stretched far in different directions).\n\nEdit: Holy shit, there are a ton of inconsistencies caused by copy-pasting. I've done my best to fix these. "
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2d784w | how do blind people determine their sexual preferences? | How would you know your attraction to a specific gender or feature if you were unable to see? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2d784w/eli5_how_do_blind_people_determine_their_sexual/ | {
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"There's the voice, gendered patterns of behaviour, and the possibly instinctive knowledge that you don't enjoy taking it up the backside.",
"Visual attraction is only part of the whole picture. It around be interesting to see if blindness, or deafness has any effect on sexual preference, but my gut feeling is that it wouldn't. I like my girlfriend with the lights off just as much as when they are on, don't know if that's really relevant. \n",
"sound of the voice, smell of the person, conversation with the person. ",
"Truth time kids, you can be taught or conditioned to like anything. Anything....",
"I saw somewhere that Ray Charles use to try and wrap his fingers around the wrist of a girl he's shaking hands with too feel if she was heavy/attractive or not. Then again he wasn't blind at birth.",
"...you do realize you can *touch* boobs in reality, right?",
"What Do Blind People Find Attractive?: _URL_0_"
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1rwsxq | How dark/bright is our full moon compared to other moons in the solar system? | If we'd switch our moon with other moons like Titan and Io, would a full moon night be mostly lighter or darker? So is our moon relatively dark or bright compared to the other moons? | askscience | http://www.reddit.com/r/askscience/comments/1rwsxq/how_darkbright_is_our_full_moon_compared_to_other/ | {
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"Compared to other moons in our solar system, our Luna is much larger than average. [Here](_URL_0_) is a pretty good reference for moon data. Using size as the metric, Titan would be the brightest if it were transplanted to Earth orbit. As to reflectivity of each moon, that could change the results of your query. But, you're on your own there."
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4oxc20 | Human languages evolve and change over time. Is there any indication that the same is true of animal languages? | askscience | https://www.reddit.com/r/askscience/comments/4oxc20/human_languages_evolve_and_change_over_time_is/ | {
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"The only other animal that has been demonstrated to show the ability to vocalize complex and novel concepts vocally is the crow. We don't know anything about the languages (or even if you could call it a language) and dialects of crows, how complex they are, what kind of syntax they use (if they even have a syntax), we are totally ignorant there. There are a few other animals that we think can vocalize novel concepts (elephants, dolphins) be we haven't demonstrated this yet experimentally.\n\nWith crows, since they are creating new vocalizations for new novel concepts and teaching this to their offspring and peers, than that necessitates the \"language\" would change over time as new concepts are added (and presumably others are forgotten). I don't think what crows are doing would be comperable to humans though, it's almost impossible they are transmitting even close to the amount of data human language can, or that what they say is capable of carrying as complex of meanings. But I'd be surprised if there weren't definitive dialects and changes over time to these dialects in crow societies. I don't even see how it would be possible for this not to happen."
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5eyass | how big would all excess co2 be if removed? how hard would it be to remove this stuff? | In terms of American football fields (squared?) or some other landmark, just how large is this carbon dioxide?
Also: how hard would it be to remove this with trees, plankton or... big machines? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5eyass/eli5how_big_would_all_excess_co2_be_if_removed/ | {
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"We add about 33 gigatons of CO2 to the atmoshere a year. \nHistorically since the industrial revolution to 1999 we have added 1010 gigatons of CO2 total.",
"Since CO2 is normally a gas, which can occupy various volumes depending on what pressure and temperature it's at. Or even condensed into a solid such as dry ice. A football field is an example of surface area. \n\nAs another poster said, human release of CO2 into the atmosphere is 33 gigatons in terms of weight. It's a fairly easy series of calculations using dimensional analysis to figure out the volume at standard temp and pressure. Or ask in r/TheyDidTheMath \n\nThe carbon that was sequestered in the form of natural gas, coal and crude oil isn't easy to sequester the same way anymore. The conditions on earth are different. \n\nCoal is basically centuries worth of piles of dead trees that never rotted, because the bacteria and fungus that decompose trees hadn't yet evolved. Plus the trees back then contained more lignin. In modern times, dead trees generally rot within a decade. Part of that decay process releases the carbon that was sequestered back into the atmosphere. Very little of the carbon in organic matter turns into [humus](_URL_0_)\n\nEven if we could some how magically stop turning various fossil fuels into CO2, it would take a few centuries or more, for nature to restore the CO2 levels back to something similar to the pre-industrial revolution era.\n\n\n",
"Others are referring to the gas, but suppose you could take the carbon out and compress it into diamonds. Those are 3.52 g/cm^3 which works out to 287 cubic kilometres of diamond.\n\nIt's a bit hard to imagine how much that is, there are 100,000 Olympic swimming pools in a cubic kilometre. But it seems to about the size of Mount Logan. "
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ymowe | Why does water from a glass jug in the fridge always seem colder than water from a plastic jug in the same fridge? | We keep two jugs in the fridge, one a plastic Brita filter, and one plain glass with a top. We transfer the filtered water to the glass jug when there is room, because no matter how long the two have been in place the water from the glass jug seems colder.
It seems to me if they are in the same fridge, overnight, they should both approach the ambient temperature of the fridge to the same point to be virtually identical, no matter that the plastic one might be removed from the fridge a couple more times a day. All I can think is it has something to do with the density of the glass, and that the plastic warms slightly every time the door opens, while the glass does not.
Could there be any other reason? It's sometimes shocking how the glass jug water can hit the back of your throat like a mouthful of glacier water, but the plastic jug water can just seem coolish. | askscience | http://www.reddit.com/r/askscience/comments/ymowe/why_does_water_from_a_glass_jug_in_the_fridge/ | {
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3d9fbr | "Mini Ice Age" Megathread — Ask your questions here! | We've gotten a lot of questions recently about the news of a mini ice age due to decreased solar activity by 2030. The original press release only mentions the solar cycles though news outlets have been connecting it with a "mini ice age". So, if you have questions on the topic, please post them here!
* Original press release: _URL_2_
* Science Daily: _URL_0_
* Good overview by Slate: _URL_1_ | askscience | http://www.reddit.com/r/askscience/comments/3d9fbr/mini_ice_age_megathread_ask_your_questions_here/ | {
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"Should we really be calling it a \"mini ice-age\"? How much can we expect temperatures to vary? How will climate change come into play?",
"Won't increased global warming combat this effect?",
"How credible is this, that is, is there a consensus agreeing with this among_ solar scientists?",
"I think it's worthwhile to cross-link to [another post](_URL_3_) on /r/askscience which asked, \"A recent study of sun activity found that solar activity will likely drop to that of the last mini ice age in 1645... how could this affect our world given the effects of climate change?\"\n\nI'm copying the most relevant part of my answer below:\n\n > There is tons of natural variability and oscillation in the climate system. Solar activity is a big one of those. The recent Bloomberg/NASA [What's Warming the World](_URL_2_) feature is a really great way to visualize the relative effects of different natural and anthropogenic forcing mechanisms. I'm going to use radiative forcing in watts/meter^2 as a general unit to help outline the relative influences of solar variability and anthropogenic CO2. The radiative forcing by CO2 (no other anthropogenic greenhouse gases included) from 1750-2000 is 2.63 W/m2 [(NOAA)](_URL_0_). The change in radiative forcing from solar variability that occurred during the Little Ice Age was a maximum of 1 W/m2 and was [likely even less](_URL_1_) according to IPCC AR4. So, even if the radiative forcing due to solar activity dropped to Little Ice Age levels, we wouldn't expect it to cancel out the effect of anthropogenic greenhouse warming, unfortunately. It certainly might slow it, and I don't know enough (and haven't run enough climate models) to say whether the effect would be minimal or substantially slow it. But it's pretty clear to me that it wouldn't pull our asses out of the fire.",
"So what would the temperature drops be? Would it go from 90 in New England summers to 30 degree summers, and -40 in the winters? Or will the drops be less extreme than that?"
]
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"http://www.bloomberg.com/graphics/2015-whats-warming-the-world/",
"https://www.reddit.com/r/askscience/comments/3cr22e/a_recent_study_of_sun_activity_found_that_solar/"
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esyu6u | external validity vs internal validity in terms of scientific method | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/esyu6u/eli5_external_validity_vs_internal_validity_in/ | {
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"When you do a experiment, your experiment is usually encompassed but a much larger problem it seeks to address. In other words, you're hoping that your experiment can generalize to a bigger picture. An externally valid experiment does a good job generalizing to the bigger picture you claim it to.\n\nWithin an experiment, you wind up with a set of rather specific results. An internally valid experiment will offer strong evidence that the effect you see is a result of the cause you claim."
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4u310y | if omega 3 dha is essential for brain function and i don't have it in diet, how come my brain is still working? | I've been reading lately about Omega 3 DHA and realized that my diet (like diet of most people) practically doesn't have any Omega 3 in it. In last year or two I may have upped my intake of Omega 3 ALA because of flaxseed - but that's it.
Considering research is showing how Omega 3 ALA - > Omega 3 DHA conversion is like 1% how come my brain is still working properly? Or is it working properly? ;)
Also, considering my diet is pretty much the same all my life - how come my brain developed at all since I had almost no Omega 3 of any kind in my diet after breastfeeding? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4u310y/eli5_if_omega_3_dha_is_essential_for_brain/ | {
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"There may be an undiscovered synthetic pathway which supplies enough. As nutritionist learned more about nutrition there has often been a discrepancy between what had recently been learned about necessary nutrition and the obvious health of populations who do not seem to be acquiring these essentials. Humans are capable of existing on a huge varieties of diets even though we need vitamin C which most species synthesized themselves. \n\nA years worth of some vitamins are store in the body. If the body conserves and recycles what it needs there may be no need for daily intake of things. The one a day vitamin ploy was an advertising gimmick.",
"From memory, my understanding isn't so much that we don't get *enough* Omega-3, but that the *balance* between Omega-3 and Omega-6.\n\nBoth are fairly common in many foods, so we generally tend to get enough of each for our body's needs, but most people's diet contains a far higher proportion of O6 than is healthy, meaning we don't have enough O3 to match it. Add to that that the term \"essential\" when it comes to micronutrients means specifically that it must be gained from diet and cannot be synthesised in the body. (e.g. we can't make zinc, but we can make vitamin D, though making enough to cope without it in the diet is difficult further north/south than about 50 degrees)\n\nI expect (though this is totally a guess, based on the above) that our body can probably dispense of the extra O6 or something, but it's costly.\n\nAnother angle to bear in mind is that a brain that's \"working\" isn't quite the same as a brain that's working as well as it could be! For example, depression, bipolar disorder, schizophrenia, ADHD, and \"cognitive decline\" are all neurological problems linked to shortfall of O3 (_URL_1_) and there are as many again of non-neurological problems.\n\nThe good news is that there are several good sources of O3 that are easy enough to add to your diet - most notably oily fish (mackerel on toast, YUM!) and eggs. I expect there are vegan friendly options too, though I don't happen to know of any - I'm not a vegan!\n\nEDIT: apparently there are a variety of nuts and seeds that help: _URL_0_"
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1ccbel | why can't you do a square root of a negative number? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1ccbel/eli5_why_cant_you_do_a_square_root_of_a_negative/ | {
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"Actually, you can, but the concept is often too advanced to teach when you're first learning about square roots. It helps to have a knowledge of algebra under your belt first.\n\nThe square root of a negative number is something called an *imaginary number*. If you want to learn about the basics, [read *A Visual, Intuitive Guide to Imaginary Numbers*](_URL_0_).",
"The square root is the number you have to multiply by itself in order to get the number you first thought of. The trouble is, when you multiply negative numbers you end up with positive numbers.\n\nWhen you multiply, say, 2 x 2, you are taking a 2, then adding another 2, so you've got two lots of two. But when you do -2 x -2, you're not taking -2 and adding another -2. You don't have two -2s, you have *negative two* -2s. So your sum actually goes in the other direction, and you end up with positive four.\n\nThis means there's just no way of getting a negative number by multiplying two other negative numbers.\n\nEdit: I understand that, as the other respondents have said, with imaginary numbers you *can* have square roots of negative numbers. I've tried to directly answer OP's question by explaining how, algebra aside, it is impossible to come up with an actual numerical figure for a square root of a negative number. Please feel free to correct me however if anything here is wrong or not ELI5 enough.",
"You can do square roots of negative numbers if you think about multiplication in a way that lets you do that. \n\nWhen we first encounter numbers, square roots of things like 4, 9, 16, or 25 sort of make sense, but square roots of numbers like 15 or 19 are harder to understand, until we expand the way we think about multiplying, we have to learn about fractions, and decimals and irrational numbers... \n\nOnce we expand the way we think about multiplication we can do square roots of any positive number, but that leaves a big hole for negative numbers... unless you, again, expand the way you think about numbers and multiplying. \n\nIt turns out that you can think about numbers as having a twisting or turning component... for instance negative numbers are twisted 180 degrees while positive numbers are twisted by 0 degrees. And now multiplying includes \"adding the twist\" of the numbers, so a \"negative times a negative\" will add two twists of 180 degrees, or turn back around to 0.\n\nThe advantage of thinking about twisted numbers is that you can take a number with a 90 degree twist, and when you square it, adding that twist twice gives a negative number... in other words, there are \"imaginary\" numbers that are just numbers with a 90 degree twist. \n\nNow you can do square roots of negative numbers, all it took was expanding the way we thing about numbers and multiplication, just like we do when we needed fractions and decimals and irrational numbers.",
"Remember the geometric definition of a square/root: if you draw a square with 9cm^2 area, the sides of the square are 3cm. 1 m^2 area, 1m sides. So the square root function describes the relationship between the area and sides of a square. And a square can't have negative area, that doesn't make sense.\n\nNow, square roots are also useful in other mathemathics than geometry. So some clever algebra people decided that if they *imagined* a square with negative area, then they could also get an *imaginary* square root, which it turns out has quite a few useful purposes."
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4xfy3h | what is the difference between engineering and design? | I thought it was all engineering, but apparently technical problem solving is also design. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4xfy3h/eli5_what_is_the_difference_between_engineering/ | {
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"Engineering is about function, and as such is a subset of design. Aesthetics are also part of design, but don't constitute engineering."
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vm0lv | I know about Koko the Gorilla lying to his handlers and saying his kitten tore the sink off of the wall, but do animals (in the wild or in captivity) ever lie to each other in similar ways? | I'm sure animals have basic deceit (hiding food, etc), but this is would be a more advanced type of thing - lying like this is seen as a marker for childhood development and intelligence. Have there been documented cases of this behavior between two animals, rather than with humans?
EDIT: Also, even other examples of animals lying to humans would be really interesting. Thanks! | askscience | http://www.reddit.com/r/askscience/comments/vm0lv/i_know_about_koko_the_gorilla_lying_to_his/ | {
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"Generally, deception, or cheating, may or may not be an evolutionarily stable behavioural strategy based on factors such as population density. However, if an animal decides to choose a cheating strategy which goes against the set rules of a group/species, often times this individual will be punished if found out. On the other hand, this cheating strategy may actually become very lucrative based on environmental factors such as population density or resource availability. So, animals may deceive each other, but it may or may not last. \n\nAn example would be [bluffing](_URL_0_) during a contest: at certain times, mantis shrimp moult and thus have soft, easily injured exoskeletons. However, to protect their residences, they will signal to invading males who are trying to take their territory as if there was no problem, and their exoskeleton is intact. Also, birds sometimes elicit false alarm calls to scare away competitors who are foraging near them. \n\nOften, though communication is tied to body size, preventing deceit. For example, many male animals trying to threaten other males or find females try to produce the deepest sounds possible to show they are large. This can't really be faked, and is therefore an honest signal. \n\nAlso, cats kind of \"lie\" to humans when they purr, as frequencies contained within the purr mimic frequencies found in a human baby's cry.\n\nI may have danced around your question but I thought I would throw some more info out there.\n",
"Yes! [Certain birds](_URL_1_) have alarm calls for predators. This is great for the group--if one bird sees a leopard on the ground, he will sound the alarm and the group will flee. However, with significant frequency, a bird will sound the alarm *when no threat is noted*. Why?\n\nTo scatter the other birds, making it much easier for him to find fruit in the trees they were occupying.\n\nI wish I could find a more academic source for this, since it is highly interesting. Unfortunately that article will have to do for now.\n\nSimilar behavior (but for other reasons, such as conflict resolution) is also noted in [vervet monkeys](_URL_0_). ",
"For what it's worth, here's a video of a penguin stealing rocks from another penguin.\n\n_URL_0_",
"Comparing the conscious behavior of a trained, domesticated, communicative primate with fixed actions patterns of wild species doesn't seem productive. \n\nA behavior that appears to be lying/deceptive to us is still a product of evolution, naturally selected for, because it increases survival. They don't plot to deceive when a given species isn't necessarily self aware. \n\nIt's really easy to anthropomorphize other species and expect they \"think\" like us but this is usually not the case. \n\nI want to go find articles for you, but I'm about to fall asleep in my chair :( I recommend looking at how we decide consciousness in other species, for example if they recognize their mirror image as theirs and not an intruder. Also try political systems, sexual coercion, prostitution, and caste systems in other species, but perhaps stick with mammals and aves. \n",
"Once watched video of what I believe was a cuttlefish, disguising its self as a female and approaching the largest male and then mating with the female the other male was protecting behind its back.",
"I know that crows use deception to stop others from stealing their food caches. They'll return to their caches and relocate them if another crow witnessed them hiding the food the first time. I think this is pretty close to what we'd describe as \"lying\". Not sure if linking to the new scientist is ok here: _URL_0_",
"Koko is a female gorilla, by the way, with regards to \"his\" in the title.",
"[Snakes](_URL_0_) emerging from hibernation will emit female pheremones to convince other males to come near them, allowing them to warm up rapidly and increase their chances to mate.\n\nThis was featured in either Life or Planet Earth recently as well.",
"Certain new world monkeys emit false threat calls when they find highly desired food to keep other monkeys in the trees away while they eat it.",
"Here is an interesting [Radiolab podcast] (_URL_0_) about animal minds & deception at a zoo."
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dj169q | why is it so easy to see in windows at night but not during the day? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/dj169q/eli5why_is_it_so_easy_to_see_in_windows_at_night/ | {
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"Light from inside makes it easier to see when its dark outside, this is because of our focus ability in our retnas."
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9n5xwc | how do nuclear explosion tests affect the atmosphere? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9n5xwc/eli5_how_do_nuclear_explosion_tests_affect_the/ | {
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"When a Nuclear Explosion occurs on or near the ground, a massive amount of dust is thrown up into the sky, moreover, this is dust that recently underwent a nuclear explosion. The Dust itself blocks out sunlight, which can lead to a temporary Nuclear Winter if enough explosions happen at once, due to high-altitude dust circulating around the mid-atmosphere, blocking sunlight from reaching the ground. As the heavier dust falls on the ground, it (being irradiated) will cause radiation poisoning to anybody who eats food that's exposed to the debris, or is outside. (Hint: the best places to be safe in case of a nuclear attack are the same as if a Tornado is coming. Make sure you have food and water, hide for at least 24 hours after the flash) \n\nAnother effect is that of an ElectroMagnetic Pulse, aka an EMP. Electronics within a radius will shut down, but this will not affect humans particularly badly. If a nuke is coming, and you want to protect your phone, stick it in a nearby microwave. A microwave will keep Electromagnetic radiation out just as well as it keeps it in. \n\nThat's about it, as far as I know. "
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dazlyx | what makes villain songs sound sinister and evil? why does certain music evoke specific emotions in our mind? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/dazlyx/eli5_what_makes_villain_songs_sound_sinister_and/ | {
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"I would say it is mainly cultural and based on codes followed from the beginning, in Western culture, happy songs are composed on major notes and sad songs on minor notes",
"To put it simply, western music typically falls into two categories, Major scale (happy) and Minor scale (sad or dark etc). The scale depends on what notes are used and vice versa. So \"villian\" music is typically written in minor. This combined with social norms and possibly some neurological or evolutionary reactions makes us think \"evil\". This \"evil\" sense is really driven home when a piece incorporates the flattened 5th (The 5th note in the scale is a semi tone lower). This is predominately done in metal music to evoke that feeling of \"evil\". If you listen to Black sabbath, by Black Sabbath, from the album Black sabbath, you will hear this flattened 5th used to great effect.",
"It's partially due to the key. Songs in the minor key sound far more sinister. Here's the Imperial March in the major key and its in no way sinister like the original _URL_0_",
"It is just an association, just like many of our villains are based on 1930s heroes until they lost.",
"I see a lot of “society” comments but no actual proof. There have been certain tones that we have associated with more serene/holy/mythical/whimsical for a millennia or more.",
"Outside of musical theory, a lot of those associations with villains are just happenstance that evolved into cultural norms. For instance, the sub-genre of Surrealist music, intended as a musical representation of Dali-esque moods, became popular in French and German cinema that was intentionally unnerving or abstract. It started to creep into American films for a while (*The Maltese Falcon*, fuckin' *Fantasia*) before fading in the McCarthy-era 50's, where villain themes were your standard John Ford grandstanders. It's been brought back several times since then, but generally, it's the music you hear when a character reveals that they're batshit crazy, often accompanied by breaking glass sounds.\n\nSo an utterly specific sub-genre intended to reproduce the feelings you get looking at a melted clock painting from 102 years ago is now the music you hear when Dennis Hopper starts talking.",
"In addition to what has been said, there are also some cultural clues. Rhythm for example (regular sounds more ordered, syncopated sounds more archaic) or instrument timbre.\n\nWarcraft 2 music (and a lot of video game music in general) is actually a great example for that. Human soundtrack is full of marches, that sound orderly, military, with horns and other brass instruments, to the same effect. Orc music is very syncopated, with irregular beats recalling barbaric nature of orcs, as well as a lot of harpsichord, which is perceived as an archaic instrument.\n\nThese clues are cultural, we associate them with those meanings because that's what popular culture has gotten us used to.",
"Nobody seems to understand the question. He's not asking about what notes are sinister, he's asking why they're sinister. What in evolution/society has made these notes invoke these emotions. Does some ancient predator sound like minor notes?",
"So far the answers are just about major vs minor but no explanation as to why they have that perception.",
"Two things: \n\n1) the use of minor keys almost exclusively. We don't know why, but generally people associate major keys with positive emotions and minor with negative emotions.\n\n2) The tritone. In music theory, the tritone/flatted fifth/ \"diabolis en musica\" is the effect of stacking three major thirds on top of each other which drops the perfect fifth (the second most stable note in a key next to the tonic or \"root\") down one half step. This puts the note right smack dab in the middle of of both octaves in the key and, for whatever reason, we find that interval especially jarring and unpleasant. Through hundreds of years if musical association, that interval has been associated with the Devil and, in general, all things evil (hence the Italian name for it listed above).\n\n(The minor second - or, as I like to refer to it, the \"Jaws Interval\" - is also quite dissonant and can deliver the same effect. Same with just moving chromatically - moving between all 12 notes in the Western scale - up or down the scale.)",
"I dont know if this was talked about but basically consonant and dissonant chords and the way we were raised. Consonant chords are chords with notes that are normally two or three notes (For example, A, C, E and G would make a consonant chord) and dissonant chords are when some notes are next to eachother and sometimes have flats (A,B,C, G would be dissonant). Another factor is the fact that dissonant chords are played during distressing times in movies, shows, plays, and etc. While consonant are played during happy times. I remember reading about a study done in third world countries where they dont have access to pop culture, and they recorded that people didnt find dissonant chords sad or consonant chords happy, most thought they gave similar \"emotions\". But yea, dont know if this was posted or not and I'm just an average guy so dont take this as fact. Dont trust everything you read on the internet lmao",
"To add to these comments, this science goes even deeper. Math plays a big part in how we experience music.\n\nA basic way to look at this is to imagine a guitar string. We shorten that guitar string by fretting the guitar, this causes the notes to get higher pitched. If we use the most basic fractions with the lowest denominators, we get the “easiest” tones to differentiate, and the easiest to combine into harmonies.\n\nIf you divide the string by 1/2 you get the same note an octave up, easy to understand. If you divide it by 1/3, 1/4, 1/5, you get some of the most basic notes of the major scale.\n\nThe higher the fraction’s denominator, the more “odd” and unharmonious the notes are likely to sound when combined.\n\nI am not an expert and this might be a faulty analysis, but the way I understand it is that a lot of this has a root in what sounds are easy to hear and distinguish, also over long distances, through walls, through our mothers’ tummies when our hearing develops in the womb.\n\nThis creates a somewhat universal concept of harmony and disharmony. In addition, sudden dynamic shifts, subverting cultural norms, and any other tool to create a sense of unpredictability can make music seem more “bad guy”. It’s important to realize that on a subconscious level we are all significantly more music savvy than on a conscious level, so we’re likely to feel something from music long before being able to pinpoint why.",
"Short answer is that villain music has lots of dissonant chords, as opposed to resonant chords. A good example of dissonance is a minor second chord, used in the shower scene from Psycho. It's not 100% understood why certain music evokes certain emotions, but from what I've seen, it's mostly a societal thing. What might be a sinister sound in one culture might not be in another"
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174rgx | what is a metabolic rate and how do i find out mine? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/174rgx/eli5_what_is_a_metabolic_rate_and_how_do_i_find/ | {
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"The Basal Metabolic Rate is an estimate of the amount of calories you burn in a day when doing 0 activity. It's an estimate based on a number of factors.\n\n_URL_1_\n\nThis calculator helps you get a baseline. There are more accurate calculations that can be done with more data, but this suffices for most purposes.\n\nTo get an idea of the actual amount of calories you burn in a given real day (with all the days walking, activities, etc), you need to multiple your BMR by a factor based on your average activity level.\n\n_URL_0_\n\nFor example, for a sedentary person, multiply your BMR by 1.2. The resulting number is the number of calories you need to eat in a day to maintain your **current** weight. Eat less than that every day and you'll gradually lose weight. Eat more, you'll gain."
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2s2ted | why are plug points made differently i.e plugs in the us are flat pins while in india they are round pins | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2s2ted/eli5_why_are_plug_points_made_differently_ie/ | {
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"Because the first company to make the plugs made them that way. They sold the plugs and the outlets. If you wanted your device to plug into their outlet, you had to use the shape. If you wanted to market an outlet that can accept the plugs that devices are using, you had to use that shape.\n\n\nMore and more international hotels are adopting to use multi prong compatible outlets. "
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bkeoo9 | when your sick with a cold why do symptoms like sneezing and runny nose seem to stop when you're sleeping but start again as soon as you wake up? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bkeoo9/eli5_when_your_sick_with_a_cold_why_do_symptoms/ | {
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"Being deeply asleep is a vulnerable time for your airway. It's best for the body not to pump pints of mucus into the throat and mouth as you auto breathe in deep sleep. It makes sense for the body to shut these mechanisms off as you sleep to protect your breathing."
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14u7ys | Which planetary body in our solar system would be the best candidate for human colonisation? | askscience | http://www.reddit.com/r/askscience/comments/14u7ys/which_planetary_body_in_our_solar_system_would_be/ | {
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"Mars would probably be the only planet (some of the moons of the larger planets might be good too).\n\n\nFirst of all, gaseous planets are out of the question so that leaves us with three choices (namely Venus, mercury and mars). Then, warming up a planet that's too cold (by terraforming using greenhouse gases) is much easier than cooling down planets that are too hot.",
"There's no easy answer to this question! But let me give it a try. \n\nFirst there is actually a fairly small body of knowledge related to each planet or moon in a solar system. We've sent experimental probes to learn more and we have good data and plenty of theories but all with very little certainty. So I'm going to answer this based on our current knowledge, but if we make new discoveries this answer may very well change. This is a reason why we do planetary exploration and missions to other planets.\n\nThis [wiki](_URL_0_) article is pretty good and has up to date information however my money is on mars as the best possible solution if we were to start tomorow.",
"Surprisingly, Venus and Mercury have a lot of potential, probably more then Mars. Floating colonies on Venus would offer no or little pressure differential between indoors and outdoors, while Mercury actually has a wide range of temperatures, from freezing to molten lead. And both of them have lots more solar power then Mars."
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5vy702 | why does a car under a carport not accumulate dew in the morning? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5vy702/eli5_why_does_a_car_under_a_carport_not/ | {
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"Because the carport protects your car from cooling down quicker than objects around them. The dew or ice builds quicker on surrounding structures than on the car, partially protected under the car port.",
"Dew happens when objects become cooler than the air, enough that water condenses (hence the \"dew point\" often mentioned in weather reports). Obviously the air can't make them any cooler than the air itself. \nHeat can pass by conduction, convection, and radiation. The first two will tend to keep the car the same temperature as the air surrounding it, so it's the last. \nA clear night sky is at a temperature of about three degrees kelvin, plus whatever radiates from the thin cold atmosphere. Objects exposed to clear night sky radiate heat faster than the air around them can warm them up, getting cold enough to form dew. Objects not exposed to clear night sky are kept about air temperature, so nothing condenses until the air itself is cool enough to form fog. \nedit: missed a word. Couldn't stand to look at it."
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250qzx | In the making of black and white movies, were props actually colored or grey? | Things such as lamps, furniture, etc.. that were specifically needed for the set. I would imagine things such as desks, books and other generic stuff were colored because they were real, but things made out of cardboard or other materials made JUST for the movie, what color were they? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/250qzx/in_the_making_of_black_and_white_movies_were/ | {
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"You may want to have a look at _URL_0_ which has some comments (and videos) with examples.",
"It depends on the circumstances and the production. Specific shades or colours would sometimes be used because they would read better with particular types of film (This is especially common later, in television, because early television cameras had really odd colour properties). Sometimes sets would be painted in black and white, and other times set dressers would use off-the-shelf fabrics and paints.\n\nIt's important to note that even if you dress a set entirely in black and white, it won't look exactly the same on film anyway, and colour choices can help tune the contrast and highlights of a monochrome image. The norm has generally been to not make \"grey\" items specifically for film and television production, simply because it's more intuitive, but there are plenty of exceptions.",
"Nope, they were in color. Sometimes, the colors were chosen less for actual aesthetics in person, and more for how they'd look in black-and-white. For example, here's the [Addams' Family set](_URL_0_)."
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2p6s6m | what exactly is "irreparable" about what green peace did to the nazca lines? | As far as I can tell, there was no damage to the actual humming bird, they just rolled out some yellow tarps next to them. I'm not saying it was a good idea and it certainly had potential to damage the lines, but I don't see how repairing it isn't as easy as rolling up the tarps.
[If you missed the story](_URL_2_)
[before](_URL_0_)
[after](_URL_1_) | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2p6s6m/eli5_what_exactly_is_irreparable_about_what_green/ | {
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"As far as i can see it's less about actual physical damage as much as it is about the integrity of the site as a whole. Stonehenge is the same way, can't walk anywhere near it. I think it is more a principle that they damaged than anything else.",
"The whole place is a restricted area, because there's a layer of bright sand beneath the darker rocks. That's how the pictures were made - remove the top layer, expose the brighter sand beneath.\n\nUnfortunately, they marched there in single file and made a deep path, and then shuffled some stones about, so it really might be quite challening to restore the place to a \"can't tell anybody was there\" state.\n\nFucking up a world heritage site of the host country of a climate summit to push for action on climate change, that's bad diplomacy level infinity.",
"The site is -very- strictly controlled to prevent damage to the very fragile images. Even Peru's president can't just go there...he'd need special permission and an escort. Scientists studying the area are allowed in in limited numbers, wearing special rubber 'snowshoes' that spread their weight out so they leave minimal traces of ever having been there. \nThe Greenpeace idiots stomped in, deliberately moved and disrupted some of the darker stones, and left very visible marks of disturbance in the area. It is pretty likely that this cannot be repaired in any way. \nSo they damaged a World Heritage site out of a self-absorbed desire for attention. I hope Peru cam recover damages with an appropriate lawsuit. "
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|
4095fb | why is a good night's sleep better than last minute study the night before an exam? | I've read that getting the recommended sleep is much more important than cramming study which would result in few hours sleep the night before an exam. But how does little sleep affect memory during an exam? Is it better to just get the sleep? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4095fb/eli5_why_is_a_good_nights_sleep_better_than_last/ | {
"a_id": [
"cysesi9"
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"score": [
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"text": [
"Its hard to concentrate while tired. Sleeping also stores your short term memories into long term ones.\n\nYour brain needs sleep before it properly stores info from that day.\n\nIt also has an emotional effect. Being tired and moody means bad attitude for test."
]
} | [] | [] | [
[]
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|
8wvtf7 | How did the icecaps end up so much higher than ocean level? | askscience | https://www.reddit.com/r/askscience/comments/8wvtf7/how_did_the_icecaps_end_up_so_much_higher_than/ | {
"a_id": [
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"text": [
"What do you mean exactly? If you're talking about sea ice, it's floating in the water just like and ice cube in a glass of water. If you're talking about continental glaciers, they form not from seawater but snowfall accumulated over many thousands of years."
]
} | [] | [] | [
[]
] |
||
4xwzkg | Could the extreme temperatures and pressures seen in collapsing bubbles during cavitation possibly be used for nuclear fusion? | [This](_URL_0_) paper mentions how bubble collapse during cavitation could possibly be used for nuclear fusion *if* the model that predicted interior shock waves is correct. I'm having a hard time finding information on whether that idea has been proven or disproven yet. If the predicted 10 Mbar pressures and 10 million Kelvin temperatures can indeed happen, would it be possible to use cavitation for the fusion of, say deuterium-tritium? | askscience | https://www.reddit.com/r/askscience/comments/4xwzkg/could_the_extreme_temperatures_and_pressures_seen/ | {
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"There was a controversial claim around 2008 that collapsing bubbles could induce nuclear fusion. This is generally not considered to be real by the scientific community, and the principal researcher on the project was found guilty of academic misconduct. Although it's hard to measure temperatures for such brief and small events, measurements generally put it in the [tens of thousands](_URL_0_) and not the millions."
]
} | [] | [
"http://etd.library.vanderbilt.edu/available/etd-06172013-143310/unrestricted/Ramsey_Dissertation_Final_2013.pdf"
] | [
[
"https://www.physicsforums.com/insights/explosion-generated-collapsing-vacuum-bubbles-reach-20000-kelvin/"
]
] |
|
8ikuec | What are the biological differences between Homo Sapiens and modern Homo Sapiens Sapiens? Or is this just a historiographical term? | askscience | https://www.reddit.com/r/askscience/comments/8ikuec/what_are_the_biological_differences_between_homo/ | {
"a_id": [
"dyuo2b2"
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"score": [
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"text": [
"None. *Homo sapiens* is reserved for the \"anatomically modern human\", which doesn't mean that there are no biological differences from that point onward, but rather than the range of biological differences 150,000 years ago is contained within the range today.\n\n*Homo sapiens sapiens* has two possible uses historically. At one time it was a reference to cromagnon man, now usually called \"early modern european humans\", to distinguish them from all other humans. For a long time ancient humans from different continents were assumed to be different subspecies. This is now known to be taxonomically invalid.\n\nIt is also still used sometimes today to refer to all humans, as a way of indicating that modern humans comprise a single extant subspecies. Implicit in this is that there are other subspecies of *Homo sapiens* that are now extinct. In fact, it is still undecided whether a number of other hominids should be classified as distinct species, subspecies of our own species, or something else."
]
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[]
] |
||
69pxfj | why do animals do the "zooming" thing where they run around a small area really quickly with seemingly no purpose? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/69pxfj/eli5_why_do_animals_do_the_zooming_thing_where/ | {
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"Can someone link a video or explain what \"zooming\" is? I'm not following at all.",
"Some animals do this as an expression of happiness. I work a lot with rabbits and farm animals that run for joy. Like rabbits will zoom around and sometimes bounce in the air/\"binky\" (leap for joy) Cows, llamas and goats also run short areas for no reason. Rabbits run in patterns that seem to have no purpose but they mean something in rabbit behavior. Like circling often is affection or playing tag. I am unclear on the biological reason to tear around in a small space on a professional or technical level. I assume it's also just fun like running around the yard as a kid, just in animal form. Also in rabbits they run at another rabbits in fights and do crazy jumps so it could be something like play but to hone skills.",
"I see that toddler kids do this alot as play in almost like a tag like game. My dog also did this heavily as a puppy when he wanted played with and rough housing. So my bet is that its pent up energy and having fun."
]
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[],
[],
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||
6x9h93 | if basically all planets are made from the same random flyby.. then why are they so diverse? | How can one planet be like "oh, I'm all that gas", and another "Mostly this metal here".
If I spray a wall with different droplets of paint over a day, the entire wall will be the same homogeneous messy grayish tint. So why are Planets apparently collections of individual stuff to such a degree? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6x9h93/eli5_if_basically_all_planets_are_made_from_the/ | {
"a_id": [
"dme6h52"
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"score": [
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"text": [
"The Sun. You don't get gas giants close in because the stellar wind is too strong for much gas to stick around. It's also hotter, meaning the gas is more energetic and less likely to hang around forming protoplanets. "
]
} | [] | [] | [
[]
] |
|
f3o1uv | what is the scp foundation? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/f3o1uv/eli5_what_is_the_scp_foundation/ | {
"a_id": [
"fhjzufp",
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"text": [
"A collection of stories about weird paranormal stuff people have created, for fun.\n\n_URL_0_",
"It’s a fictional universe written by a bunch of random people on the internet working together. \nThe premise is there is the titular SCP foundation (Secure, Contain, Protect), that contains paranormal items and keeps them secret from the general public. \n \nThe origin was a “creepypasta” horror story on 4-chan. \nIt appeared to be a clinical description about containing a statue that moved if you didn’t look at it, and would break people’s necks. \n \n(Further trivia, this post appeared several weeks AFTER a Doctor Who episode featuring statues that moved when not being looked at. Just check the date stamps and air dates, that SCP was AFTER the weeping angels. \"Blink\" aired 9 June 2007, the original SCP-173 4-chan post first appeared on 22 June 2007 ) \n \nThe description implied:\n1) the existence of an organization that handled paranormal \n2) that this statue was just one of many such objects. \n \nSo naturally there were copy cat posts for other objects with similar formatting. \nEventually someone started a wiki to host these stories. And further material was made to flesh out the setting. \n \nYou can visit that wiki at:\n_URL_0_"
]
} | [] | [] | [
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"http://www.scp-wiki.net/"
],
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"http://www.scp-wiki.net/"
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||
cfpszg | in old crt's why does physical damage to the tv cause the picture to rise, disappear, and then reappear in that order constantly? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/cfpszg/eli5_in_old_crts_why_does_physical_damage_to_the/ | {
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"The electron gun paints the picture line by line from bottom to top. It starts from scratch after every frame, 60 times every second. \n\nHitting it can cause the gun to jump around, causing refractions and making the process much more noticeable alternatively it makes the gaps large enough by physically forcing the gun to draw on a new part of the screen",
"The picture on a CRT is made by a beam of electrons from an electron gun hitting the screen and making tiny dots on the screen glow. The beam scans left to right for each row of the image, and then jumps down to the next row, until it reaches the bottom of the screen and starts over again. \n\nAt the same time, the beam constantly changes in strength: more electrons make a brighter spot on the screen. There is a short period of time between when the beam hits the bottom of the screen and when it hits the top again during which no electrons are shot out of the gun. \n\nIn order for the image to appear properly centered on the screen, the moving of the beam has to be synchronized with the strength of the beam. In older TVs, this is done entirely with analog circuits having adjustable components. Hitting a TV can knock one of these adjustable components a little, causing the TV to lose sync. On these old TVs, there is sometimes small screw adjustors on the back: V-sync and H-sync. turning the V-sync will fix the problem."
]
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[],
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||
1daory | why retrospective review is not used in soccer to aid accuracy of the decisions called | For example, when someone scores from receiving the ball in an offside position but the linesmen and referee do not call for offside and allow the goal to stand. Reviewing the footage, as is often done by commentators, is able to show decisions called incorrectly.
Could someone please ELI5 why the match officials do not embrace this facility as is the case in numerous other sports. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1daory/eli5_why_retrospective_review_is_not_used_in/ | {
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"text": [
"- _URL_0_\n\n- _URL_1_",
"One of the appeals of soccer is that the game doesn't stop. When the first whistle blows, the clock starts and keeps going until half time, and then process repeats in the 2nd half. A lot of people prefer this continuous gameplay over the constant starting and stopping that is found in games such as football, baseball, basketball, and hockey. If the refs were allowed to review plays, then the continuity would be lost. ",
"I think it would be a good idea, but would never be implemented for at least 3 reasons:\n\n1. Part of soccer's appeal is the fluidity of the game. The timer never stops, and neither does play for very long, even after goals or injuries. Add instant replays and the action will come to a grinding halt.\n\n2. For better or for worse, the controversy that \"bad\" calls bring to the game actually increases its popularity. Would it be more sportsmanlike for fights to be banned from hockey? Sure, but that's part of the appeal of the sport. I'm not saying that people watch soccer to get pissed off at controversial calls, but you have to admit that they give people things to talk about during and after games.\n\n3. People don't want to see the most popular sport in the world brought any closer to American football."
]
} | [] | [] | [
[
"http://www.reddit.com/r/soccer/comments/pd8r2/use_of_technology_in_football/",
"http://www.reddit.com/r/soccer/comments/13ccsc/what_is_rsoccers_thoughts_on_offside_technology/"
],
[],
[]
] |
|
1uybwb | Will breathing in hydrogen gas make your voice even higher than from breathing in helium? And will it kill you? | I saw a demonstration on Mythbusters where Adam breathed in a heavy gas and his voice got lower. He also performed the age old party trick of breathing in helium. My question is would breathing in hydrogen, a lighter element, make your voice go even higher? And can you actually try this without dying? | askscience | http://www.reddit.com/r/askscience/comments/1uybwb/will_breathing_in_hydrogen_gas_make_your_voice/ | {
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"cemx6qs"
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"The only danger associated with inhaling hydrogen gas (so long as it doesn't ignite) is possible asphyxiation due to the lack of oxygen being inhaled. This danger also exists in inhaling helium and to the same extent. So as long as the helium doesn't kill you, you can perform the same actions with hydrogen instead. _URL_2_ \nThe change in timbre associated with Helium is the result of a change in the velocity of the sound waves and is entirely dependant on the speed of sound through the gaseous medium that you are using. \n_URL_1_\n _URL_0_ \nSound moves faster in hydrogen so you are correct and the sound will be even higher in timbre.\n\n"
]
} | [] | [] | [
[
"http://www.phy.mtu.edu/~suits/SpeedofSoundOther.html",
"http://chemistry.about.com/b/2013/08/26/helium-voice-is-not-higher-in-pitch.htm",
"http://en.wikipedia.org/wiki/Hydrogen_safety"
]
] |
|
4imfcd | why does whipping cream make it fluffy? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4imfcd/eli5_why_does_whipping_cream_make_it_fluffy/ | {
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"The whipping action forces air into the cream, where it gets trapped. The trapped air is what makes the cream light and fluffy.",
"The protein molecules in cream have formed formed a gel matrix, or foam, by being repeatedly beaten and whipped, which allows it to denature slightly. This denaturation allows tiny pockets of gas or liquid to become trapped in the matrix, which gives it a fluffy, light texture.\n\nSource: Food Science Major"
]
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[],
[]
] |
||
5f9bju | what is rico law? | I've tried reading wikipedia and the many other sources out there, but I'm not quite 100% on understanding what it is, what it's used for, and when it's used. I understand that it's for prosecuting those in organized crime, but *when* is it used in these cases? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5f9bju/eli5_what_is_rico_law/ | {
"a_id": [
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"I don't know all the details, but RICO stands for \"Racketeering-Influenced and Corrupt Organizations\", and it allowed prosecutors to lay charges against you just for being a member of, or being corrupted by organized criminal organizations like the mafia, the triads, motorcycle gangs and Latin American drug cartels. This gave the law a really powerful club to use against organized crime, and it worked really well in many cases, especially against the mafia. In particular it gave the law the power to seize any assets that were probably purchased with money made from the proceeds of crime, so drug lords and mafia dons had their homes, cars, boats and golf courses sold for auction, which was very nice to watch.\n\nUnfortunately, many prosecutors also abused RICO and used it promiscuously in cases where it clearly didn't apply. They called groups of three 17 year olds selling pot \"corrupt organizations\" and sent the kids off to prison for 40 concurrent life sentences. They seized the homes of parents of minor drug offenders, and in one infamous case, seized most of the homes in a primarily African-American town in the South because a single drug dealer claimed that everyone in the town were his accomplices, even people who clearly never even met him!"
]
} | [] | [] | [
[]
] |
|
35znoy | What happens if a train hits you at 1 mph? | My friend and I were having an argument and I said if a train hits you at they speed it won't do much, but he said that a train has the force of a car going to 60 mph. | askscience | http://www.reddit.com/r/askscience/comments/35znoy/what_happens_if_a_train_hits_you_at_1_mph/ | {
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"text": [
"You're both right in a way. I suspect what he's talking about is the momentum of the train (mass * velocity). The train is exceedingly heavy and so even though it's travelling very slowly, it has a large momentum and is very difficult to stop - even at 1mph. That said, if you were to get hit by a train at 1mph, you'd suffer no damage but you'd certainly be unable to stop it by pushing back.",
"Your mass is negligible compared to the train, so it would be sort of like being hit by a planet at 1 mph, which is what will happen if you fall about one centimeter. If you fall flat on your face from that height it would still probably hurt a bit, but it won't cause any real harm.",
"Absolutely nothing. This would be like walking very slowly into a wall. If you add constraints like you can't move, of course it would crush you. If you were laying on the tracks it would slowly run you over. But what kills you is the acceleration which in this case is minimal. This is about as dangerous as an escalator - literally.\n\nThe train doesn't have \"force\" - it has momentum and kinetic energy and a velocity with respect to you. You solve for your final velocity after the collision and figure out the acceleration you would experience. In this case, your final velocity will be 1 mph. Thats 0.44 m/s. That's how fast you are going if you fall about 1 cm. This would feel like falling 1 cm onto a hard surface.",
"Consider the *impulse* that would be delivered to you in each case, which just describes how much your momentum (mass * velocity) changes by. Dividing the impulse by the time it took to deliver it will give you the average force applied; Force=(mass)(change in velocity)/(change in time). Now, let's say that energy is being expended so that these things are traveling at these same speeds after the collision. It's clear here that for the same massed you, you go through a greater increase in momentum when the car hits you. We're concerned with how *fast* this change takes place, however, as it is this that describes the force acting on you. I would wager here that although getting hit by the 1 mph train would cause a very abrupt change in momentum, the speed still small enough and the train light enough that nothing too bad'll happen. In theory, however, (referring back to Force=(mass)(change in velocity)/(change in time)) we observe that the smaller the change in time that takes place during your change in momentum, the larger the force that is acting on you. Therefore, if the train coming at you were heavy enough, your friend would be right. Irl I doubt there's a train even close to being that massive."
]
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|
1pngem | Cauterization in the ancient/medieval world | Prior to the advent of modern medical practices, how extensive was the use of cauterization? For what types of wounds would it be used? More a medical than historical question, but relevant: what are its advantages and disadvantages compared to, say, stitches (which were also used, correct?)? Where (and when) in the world was and wasn't cauterization used? I know it was described by Hippocrates (or another Greek physician), but not much else. | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1pngem/cauterization_in_the_ancientmedieval_world/ | {
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"I always enjoy pulling out my copy of Manjo (1975) *The Healing Hand: Man and Wound in the Ancient World*, because despite being almost four decades old it continues to deliver.\n\nManjo asks a similar question: How could it take so long to understand something so simple -- in concept -- as turning off a faucet? He then goes on to identify some key barriers:\n\n- Lack of knowledge of circulation stymieing the concept of \"turning off a faucet\" in general. I'll just note here that it wasn't until William Harvey in the 17th Century that Galenic and Pre-Galenic ideas about circulation were finally refuted. Those refuted ideas could best be summed up as \"blood in the veins doesn't circulate and arteries carry air.\" Although in Galen's defense he posited that arteries held both air and blood, although he did accept that the venous and arterial system with separate and non-overlapping.\n\n- More for ligatures than cautery, but without an understanding of germ theory, attempts to staunch bleeding might merely trade a quick death by exsanguination for a lingering death by other means. Same with non-sterile stitches and sutures, though either introduce a pathogen or give give existing bacteria in the wound a new substrate for growth.\n\n- Wounds requiring cautery might be fatal themselves. Your perforated colon is not going to care if you managed to stop bleeding out. \n\n- Returning to incomplete ideas regarding circulation, Manjo notes that if \"the blood lost is only that which was contained in the wounded part, [this] deprives the event of some of its urgency. Again, if you don't know that that blood is a constantly circulating substance that can only be replaced at a finite rate, but instead see it as a relatively stable medium, a nick to the femoral artery might not seem like that big idea. He cites Celsus as saying bleeding can be stopped with a red hot iron or by applying a \"[suction] cup to a distant part [of the body], in order to divert thither the course of the blood.\"\n\nThat said, Manjo identifies several pieces of historical advice where cauterization if called for, even if not explicitly intentionally. A passage in the Ebers Papyrus, for instance, advising knives for cutting open cysts/abscesses should be heated and avoid blood vessels. Regular, if not particularly focused, use by Ancient Greeks. Allowing cones of incense to burn down to the skin to seal ulcers in China. And as part of the regular training ayurvedic vaidya. The technique wasn't completely absent, it just wasn't in wide use or always used for what we associate with cauterization today, nor does the term \"cautery\" in historical usage -- simply meaning the application of heat -- exactly match up with the modern idea of searing and burning.\n\nHippocrates, for instance, recommended that applying \"irons that are not red hot\" to the inside of the eyelids of a person about to undergo eye surgery. He also recommends using cautery on the lower back and buttocks for more general ailments. These actions were based around humoral theory though, not actual biological processes. As [this paper](_URL_0_) puts it: \n\n > The drugs most commonly utilized by Hippocratic physicians were purgatives: emetics, laxatives and nasal insertions, the common aim being to eliminate noxious matter, by diverting it to a bodily orifice or, if necessary, to an opening created for the purpose. Cautery and cutting fulfilled broadly similar functions, the aim being to reduce unwanted bodily moisture or to eliminate fleshy tissue."
]
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[
"http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2629169/"
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k7uo7 | md5 hashes | How are they generated, why are they always 32 characters in length and why are they not reversible? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/k7uo7/md5_hashes/ | {
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"I'll field \"why are they not reverseable\". \n\nConsider: They come from any length input to 32 characters long. \n\nSo, there are *more* inputs than outputs. This means that there are md5 hashes that have more than one input. Since an md5 hash could've been generated by any of those, the *best* you could hope for is to generate a list of all of those, of which there are infinitely many.\n\nAnother example is consider a 1 bit \"hash\" function: 1 if the number is odd, 0 if it is even. Now, if I give you the hash 1, what was the input? Well, it was even...but that's all we can know about it.\n\nThe usual analogy is a telephone book. If you were given a telephone book and asked to find the phone number of \"Lorenzo Von Matterhorn\", you could do it and fast. But, if I gave you the phone number 555-9871, and asked you to find it in the phonebook, it would be an extremely time consuming job for you.\n\n ",
"Hashing is when you want to create an unique ID number for any piece of text or data, like a fingerprint.\n\nThe simplest hashing recipe is convert each character of text into a number, then multiply all those numbers together to get a really big number. If the big number is too big, then divide it by the biggest number you'll allow and take the remainder: that's your \"unique\" hash code (think \"ID number\") for that text. \n\nThe MD5 recipe is a lot more complicated than this but the biggest number allowed is 32bit (around 4 billion) because it provides a reasonable amount of uniqueness for most applications without being too big to work with easily.\n",
"It is a mathematical formula. It is 32 bits because computers are 32 bit machines. It's convenient. There could also be 16 bit hashes. Checksum is another form of a hash. Basically, you take any number or binary data sequence of any size and you run it through a complex formula. It operates on the enter binary file and gives a 32 bit output. The formula must be complex enough to detect even small changes in the binary data.",
"A hash is like a fingerprint.\n\nIt doesn't contain much information. You can't tell from a fingerprint how tall someone is, their age, their gender. All you can do is try a bunch of people until you find a match.\n\nHashes are the same way. They tell you one thing and one thing only...that the data generated this string of characters.",
"The answer to why an MD5 is 32 characters long is, because. It's really that simple. Because. The guy that invented it decided that no matter what you put into the hash function, the answer that comes out the other end should always be the same length, and he chose 32 characters.\n\nTo calculate an MD5 hash, you take a bunch of data and pretend it's just a big long list of ones and zeros (bits). First, you take the first 512 bits. This is the first \"block\" of bits. You break that block of bits into four 128 bit pieces. You then do a bunch of math to take these four numbers and smoosh them together in a complicated way to get a single 128 bit number. This is the hash of the first block. You take the next block and do the same thing, then take those two numbers and smoosh them together to get the hash of the first two blocks. You smoosh the hash of the third block with the hash of the first two, and keep going. When you run out of blocks, you have the hash for the whole thing.\n\nThe reason it's not reversible is because different pieces of data will hash to the same value. For example, you can think of turning your full name into your initials as a hash function. If you are Bob Elizabeth Jones, your initials are BEJ. If you tell anyone to take the \"hash\" of your name, anyone will get the same answer, BEJ. But the think is, there are other names that have the same initials, like Beatrice Earnest Joplin. You can always figure out someone's initials from their name, but you can't tell their name from their initials.",
"I'll field \"why are they not reverseable\". \n\nConsider: They come from any length input to 32 characters long. \n\nSo, there are *more* inputs than outputs. This means that there are md5 hashes that have more than one input. Since an md5 hash could've been generated by any of those, the *best* you could hope for is to generate a list of all of those, of which there are infinitely many.\n\nAnother example is consider a 1 bit \"hash\" function: 1 if the number is odd, 0 if it is even. Now, if I give you the hash 1, what was the input? Well, it was even...but that's all we can know about it.\n\nThe usual analogy is a telephone book. If you were given a telephone book and asked to find the phone number of \"Lorenzo Von Matterhorn\", you could do it and fast. But, if I gave you the phone number 555-9871, and asked you to find it in the phonebook, it would be an extremely time consuming job for you.\n\n ",
"Hashing is when you want to create an unique ID number for any piece of text or data, like a fingerprint.\n\nThe simplest hashing recipe is convert each character of text into a number, then multiply all those numbers together to get a really big number. If the big number is too big, then divide it by the biggest number you'll allow and take the remainder: that's your \"unique\" hash code (think \"ID number\") for that text. \n\nThe MD5 recipe is a lot more complicated than this but the biggest number allowed is 32bit (around 4 billion) because it provides a reasonable amount of uniqueness for most applications without being too big to work with easily.\n",
"It is a mathematical formula. It is 32 bits because computers are 32 bit machines. It's convenient. There could also be 16 bit hashes. Checksum is another form of a hash. Basically, you take any number or binary data sequence of any size and you run it through a complex formula. It operates on the enter binary file and gives a 32 bit output. The formula must be complex enough to detect even small changes in the binary data.",
"A hash is like a fingerprint.\n\nIt doesn't contain much information. You can't tell from a fingerprint how tall someone is, their age, their gender. All you can do is try a bunch of people until you find a match.\n\nHashes are the same way. They tell you one thing and one thing only...that the data generated this string of characters.",
"The answer to why an MD5 is 32 characters long is, because. It's really that simple. Because. The guy that invented it decided that no matter what you put into the hash function, the answer that comes out the other end should always be the same length, and he chose 32 characters.\n\nTo calculate an MD5 hash, you take a bunch of data and pretend it's just a big long list of ones and zeros (bits). First, you take the first 512 bits. This is the first \"block\" of bits. You break that block of bits into four 128 bit pieces. You then do a bunch of math to take these four numbers and smoosh them together in a complicated way to get a single 128 bit number. This is the hash of the first block. You take the next block and do the same thing, then take those two numbers and smoosh them together to get the hash of the first two blocks. You smoosh the hash of the third block with the hash of the first two, and keep going. When you run out of blocks, you have the hash for the whole thing.\n\nThe reason it's not reversible is because different pieces of data will hash to the same value. For example, you can think of turning your full name into your initials as a hash function. If you are Bob Elizabeth Jones, your initials are BEJ. If you tell anyone to take the \"hash\" of your name, anyone will get the same answer, BEJ. But the think is, there are other names that have the same initials, like Beatrice Earnest Joplin. You can always figure out someone's initials from their name, but you can't tell their name from their initials."
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45rcyu | What was life like for a peasant living under the Knights Templar, or some other such Holy Order? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/45rcyu/what_was_life_like_for_a_peasant_living_under_the/ | {
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"I know it's a bit late, but if interested, there's a lot of reading to be done for (some sections) of life under the rule of the Livonian Sword Brothers and Teutonic Order. These groups were operating in the Baltic territories from (roughly) the 13th century until the 16th century, and you can trace that back to earlier years in some cases, such as the border skirmishes going on between Poland and the Old Prussians.\n\nThere are a few things to note, and one of which is the degree of control that these holy orders actually had over an area. In many cases, especially involving the Teutonic Order, the earlier phases of pressing into territory involved actions that we might find similar to today's interactions between western military advisers and local Afghan or Iraqi populations. While the first wave of \"settlers\" into these pagan areas tended to be missionaries, the Pope wasn't too hesitant to grant military orders the right to protect the interests of these Christians, and these Order knights were often vastly out-manned and certainly out-gunned (one can find many examples, such as the Battle of Saule, among others) that demonstrate the effectiveness of the Prussians, Curonians, et cetera, operating in their native territory and utilizing hit-and-run tactics with their skirmishing groups. To establish any real foothold in the region, the knights worked with local nobility and collaborators to construct things such as garrisons, bridges, and roads, all with the intention of settling the area and fostering a sort of alliance with the locals. In many cases, these Order-friendly settlements were besieged by fellow pagans, who sometimes coerced the converts to return to paganism (as in Mazovia during the early 13th century). Again, without drawing too many parallels, you can imagine how the Taliban treated Afghan collaborators with Coalition forces. Many of these raiding groups didn't care about the ethnic makeup of the peasants - they were striking at the Christian infrastructure and Christian-aligned garrisons, as well as any pagan groups that opposed their interests. Peasants, which includes a rather wide sample of ranks and duties in these areas, were often the ones closest at hand during raids, since they generally lived outside of keep and garrison walls.\n\nAside from the obvious in-fighting going on here, there's a much darker side to the actions of groups like the Livonian Sword Brothers. The Papacy itself issued charges against them for doing things such as extorting money for conversions, taking slaves from the local population, executing ransomed hostages, and even abusing the local Christians (typically German by birth). We also need to remember that these are only the charges that they were formally accused of - there could be many more that were either ignored or unseen by Papal advisers, or were never uncovered, since the locals had little recourse in grievance matters. A 1249 document called the Treaty of Christburg outlines some of these issues in more detail, since it actively guaranteed rights to Christian converts among the Prussian clans. These rights prevented the Teutonic Order from abusing property sales and inheritance laws, and also forced the Prussians to submit tithes to local churches and aid in their construction. So, in essence, the peasants in these areas could be either German or locals (Prussians, Estonians, so on and so forth). The Germans settlers were Christian and typically received land as a result of settling there, and as such, they might be subject to raids or other dangers, but their customs, laws, and personal rights likely weren't violated to the same extent as the pagan Balts. There are some truly hideous stories about the fighting between the Balts and the Teutonic Order, but also stories about the Balts enslaving or massacring neighboring tribes during this period, all because of the in-fighting and the constant shifting of power between the collaborating and opposing tribes. Peasants, if defined as being non-fighting, non-noble locals of the area, had varying chances of prosperity and safety depending on their region. If you're interested in further reading, here are my sources, which delve much further into each region:\n\n\"The Northern Crusades\" by Eric Christiansen.\n\"The Prussian Crusade\" by William Urban.\n\"The Livonian Crusade\" by William Urban.\n\"Teutonic Knight: 1190-1561\" by David Nicolle. \n\nAnd, of course, the primary sources, which are the Treaty of Christburg, and the Livonian Sword Brother charges, found here: _URL_0_\n\n"
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1ucj3i | how do 401ks work, and how can i understand how my account is doing? | I just graduated college and have only been working since July 2013. I have my 401K arbitrarily set up to put in 6% of my paycheck (supposed to auto-increase by 1% every year), but generally speaking I have no clue how the account works or how to know if it's doing well (I have it on an automatic portfolio manager).
Edit: wording | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1ucj3i/eli5_how_do_401ks_work_and_how_can_i_understand/ | {
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"A 401k is basically a container for your money. What the container does is it allows you to not pay income tax on that money right now, and instead you pay tax on that money when you retire. The hope is that when you retire, you'll be in a significantly lower tax bracket (because you won't have a 'real' income), so you'll pay far less in tax on that money. Also, since you can initially put in more money to the account (because it's not taxed right away), over time that money can grow more than it would it if was taxed.\n\nSo you put this money in the container, now what? Well, the container is given to you as an option by your employer, and usually your employer gets a financial company to actually handle the money for you. From a list of investment choices provided by the company, you choose how you want your money invested. You can put it all into one type of investment, or split it between them.\n\nHow you actually go about doing that, is usually on a website somewhere now. Ask your HR department for specifics on how to access your 401k options."
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27pag1 | the notion of free will as physicists understand it. | First and foremost I have a very elementary understanding of physics, but I always understood free will to be the conscience ability to make decisions, but whenever I read physics articles, physicist often say something to the effect of free will does not exist. Reading an article right now in which Physicist Brian Green, is quoted as saying "free will is merely a human sensation." Green also states that Scientific equations describe the particles that make up all matter...While more complex structures arise that have no relevance to a single particle...everything still has a fundamental underpinning" While I understand this statement I find it hard to accept it.
Weather for example is composed of many particles, but give rise to a complex system that cannot be accurately modeled. I know that it is argued that if given enough information, weather could then be modeled accurately, but my question is couldn't there be some systems which are just too complex to ever be modeled (decision making).
I can't explain it but there is just something unnerving about the notion that if given all the variables/parameters, from the big bang, it could be extrapolated that I would post this question on this day at this time, and like it or not, my curiosity about the universe had no effect.
Here is a link to the above mentioned article:
_URL_0_
edit: whether to weather | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/27pag1/eli5_the_notion_of_free_will_as_physicists/ | {
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"They're making the statement that we live in a clockwork universe and that everything that happens happens because of a series of mathematical equations. Because of this freewill can't exist because the decisions we make are based off those predictable and calculable equations. Given enough information about your brain and environment I could (in theory) predict what decisions you would make.",
"The brain is where all our thoughts come from. There has been no evidence ever of a 'soul'. With that in mind it makes sense to assume every thought, idea and will that we have as purely a mechanical process. Physicists (not all of them) are assuming that if you knew the exact location and status of all chemicals in the body and introduced a stimulus (movement, sound, light, drugs) then you could calculate exactly how that brain would react and what thoughts would form.\n\nThis leads many (myself included) to believe that free will is an illusion. That we are just machines that react to our environment.",
"Physics really has no opinion on free will. Some physicists might have opinions, but they don't \"represent\" the view of Physics, if you see what I mean.\n\nAnyway, the problem with the way you're thinking about free will is it kind of assumes that you're outside the universe in some way.\n\nUnless I'm mistaken, the train of thought is like this: \"My decisions are caused by something. *Either* they're caused by physics, *or* they're caused by me/my free will/my curiosity about the universe. So if they're caused by physics, then that means they can't be being caused by me.\"\n\nIn this model, your mind and physics are two separate things, either of which could be responsible for your thoughts and decisions. But in fact, you exist physically. You're a physical object, your brain exists in the real world and works by physics - your mind, your free will, your curiosity about the universe... is all within physics, is part of it. **You are physics**. And you're not lessened by that at all, things can be completely real and still be made up of smaller parts. Your free will is made of physics. It's not \"Do I cause my decisions or does physics cause them?\". You cause your decisions, through physics, because you are physics. Physics is not a separate thing from you that competes with you to decide your actions, it's just the way in which you exist.\n\nSo free will isn't an illusion, really, it's more of a confusion. It's an idea that stops making much sense as a concept one you break it down clearly.",
"It's really a philosophical debate based on physics. \n\nAnother way they talk about it is to ask whether or not the universe is **[deterministic](_URL_0_)**. \n\nTraditionally, this has been an either-or debate. Either everything is already determined from the initial conditions of the universe, or you have free will. This ultimately reduces to \"either our personal decisions alter the future of the universe, or we are such a small and insignificant piece of the universe that our decisions have very little or no effect on its outcome\". Since it is a pillar of quantum mechanics that everything be based on probabilities because of the uncertainty principle, quantum mechanics would seem to strongly indicate that you have to make a decision in order for there to be an outcome. \n\nThe other side is that your decision was going to happen, no matter what, since the beginning of the universe, and if we just knew what those initial conditions were and how the universe evolved, then we would know exactly what was going to happen. \n\nA more modern take on the debate is that at our scale of existence (a nice balance between quantum mechanics and the observable universe) we have free will, but the universe is ultimately deterministic. The universe is assumed to be deterministic, but due to our level of involvement as part of the universe (and a very small part), it is assumed to be impossible to gather the information necessary for human beings to utilize that underlying determinism. \n\nSo if we try to get involved and make the universe follow our free will, we are too incapable and too powerless to make any impact on the universe as a whole. Our sun will be created and destroyed, and the universe as a whole won't even notice in the long run. \n\nSo as far as our experience of nature is concerned, we have free will, but the laws of physics are deterministic, we're just missing those initial conditions, and those initial conditions would allow us to peek in on the universe's determinism. When I say initial conditions, I mean the singularity of the big bang. So it's extremely unlikely that we are going to ever be able to take advantage of determinism. It would take multiple, HUGE discoveries in physics that many speculate will never be known or understood. "
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kp5k2 | what is/would be the clock in my cpu? how does it work? | You know, the one that I overclock. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/kp5k2/what_iswould_be_the_clock_in_my_cpu_how_does_it/ | {
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"Like you're five: You know how a marching band has a guy with a little stick and whistle that marches in front? He decides how fast everybody else is marching. He usually keeps a pretty slow pace, on account of the kid with the tuba, but if he needed to he could make them march as fast as he wanted to. He could have them jogging around the field! Of course, if that happened, the music would get messed up, and some people would probably trip and fall.\n\nThe clock in your computer does the same thing. You can make it go faster by turning up the rate at which it tries to process instructions, but if you go too fast everything will crash.",
"The clock is just an electronic signal that alternates between off (low voltage) and on (high voltage) at a specified number of times per second (that's the clock speed - usually in the 1-3 GHz range). \n\nBased on the way computer chips are made, each individual circuit makes a change when it notices that the clock goes from 0 (off) to 1 (on). That's when it reads numbers from registers (circuits where numbers are stored); does arithmetic (using the arithmetic logic unit - the part of the chip that does math); and does all the other things that processors do. ",
"The CPU clock is like the \"metronome\" that sets the pace for all the other things in the CPU.\n\nIn practice, it's actually a vast network of relatively complicated circuitry spread all across the chip, that keeps all the parts from trying to send electrical signals to each other at the wrong times and screwing everything up.\n\nI'm not sure we actually know in detail how it works. I mean, in general I'm sure there are PLLs and differential transmission lines and all sorts of stuff. But making clocks that are both fast and accurate is actually a difficult electrical engineering problem - like how making the fastest car in the world is difficult and requires special tricks. The tricks to make the fastest clocks may be a trade secret that CPU manufacturers don't share, lest other people start making fast chips too.",
"Like you're five: You know how a marching band has a guy with a little stick and whistle that marches in front? He decides how fast everybody else is marching. He usually keeps a pretty slow pace, on account of the kid with the tuba, but if he needed to he could make them march as fast as he wanted to. He could have them jogging around the field! Of course, if that happened, the music would get messed up, and some people would probably trip and fall.\n\nThe clock in your computer does the same thing. You can make it go faster by turning up the rate at which it tries to process instructions, but if you go too fast everything will crash.",
"The clock is just an electronic signal that alternates between off (low voltage) and on (high voltage) at a specified number of times per second (that's the clock speed - usually in the 1-3 GHz range). \n\nBased on the way computer chips are made, each individual circuit makes a change when it notices that the clock goes from 0 (off) to 1 (on). That's when it reads numbers from registers (circuits where numbers are stored); does arithmetic (using the arithmetic logic unit - the part of the chip that does math); and does all the other things that processors do. ",
"The CPU clock is like the \"metronome\" that sets the pace for all the other things in the CPU.\n\nIn practice, it's actually a vast network of relatively complicated circuitry spread all across the chip, that keeps all the parts from trying to send electrical signals to each other at the wrong times and screwing everything up.\n\nI'm not sure we actually know in detail how it works. I mean, in general I'm sure there are PLLs and differential transmission lines and all sorts of stuff. But making clocks that are both fast and accurate is actually a difficult electrical engineering problem - like how making the fastest car in the world is difficult and requires special tricks. The tricks to make the fastest clocks may be a trade secret that CPU manufacturers don't share, lest other people start making fast chips too."
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2ed6ct | Allegedly, in 1990, James Baker pledged to Mikhail Gorbachev that NATO would not extent eastward. Some claim that this promise was actually made while others claim that it's nothing more than a myth. Which is it? | I'm currently reading a book called *The Prophets of War: Lockheed Martin and the Making of the Military-Industrial Complex* and in it William D. Hartung makes the claim, citing Leon V. Sigal's book *Hang Separately: Cooperative Securtiy between the United States and Russia, 1985-1944*, that the US promised the Soviet Union that they would not extend NATO membership to Eastern Europe.
Different sources argue either way. [This SPIEGEL article](_URL_1_) and [this journal article](_URL_0_) in the Washington Quarterly [PDF warning], for example. | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/2ed6ct/allegedly_in_1990_james_baker_pledged_to_mikhail/ | {
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"According to Gorbachev, Baker did make this pledge; according to Baker, he was never referring to anything other than Germany. Within Baker's personal handwritten notes of his meeting with Gorbachev he put exclamation points next to this statement regarding the expansion of NATO:\n\n > \"End result: Unified Ger. anchored in a **changed (polit.) NATO**--whose juris. would not move **eastward**\"\n\nThe bold represents the words and phrases that Baker put stars by.\n\nA few days later, on February 9th, Gorbachev repeated to Baker that he couldn't accept a NATO that would expand eastward. Baker said that \"we agree with that.\"\n\nMary Sarotte analyzes the diplomacy between Baker and Gorbachev particularly well in her book *1989: The Struggle to Create post-Cold War Europe*. You'd probably get more from me copy and pasting the main part of what Sarotte says on the exchange between Baker and Gorbachev rather than me trying to summarize it. It begins on p.110:\n\n > [The agreement between Baker and Gorbachev] formed the nucleus of the controversy that remains unresolved to this day. Unwisely, Gorbachev let the meeting end without securing this agreement in any kind of written form. Emerging from a political culture in which the word of a leader overruled the law, hoping that he could still find a way to disband both military alliances [NATO and the Warsaw Pact] entirely, and hesitating to agree to his end of the bargain (a unified Germany), Gorbachev did not try to resolve the matter there in writing. In the future, once NATO started expanding, he would therefore leave the Soviet Union's successors empty-handed when they protested against NATO enlargement. Later, Russian presidents would assert that this meeting had given them assurances that NATO would not expand. The United States would remember this meeting differently: as one in a number of conversations and negotiations limited solely to Germany, and until the final documents were signed, changeable.\n\nTo put this meeting into greater context, you may want to see if you can perhaps read all of chapter 3 in Sarotte's book, of which the above quote is a part of. Or you can just buy the book and read the whole thing; it's an absolutely fascinating read. \n\nEdit: Clarification",
"This comment may not belong here (it doesn't answer OP's question, but rather tries to take the discussion to another level), but I will try.\n\nI'm always hearing from pro-Russia folk like Stephen Cohen at The Nation that because of this \"broken promise\", Russia feels like it has been treated as a defeated nation. People like this usually go on to argue that Russia deserves its own sphere of influence and is right to object to NATO's eastward \"encroachment\".\n\n To this I say: beyond the real politik concern of \"poking the bear\", why should we care? If former Warsaw Pact nations want to join NATO, why should Russia be given sympathy? IMO, too bad; so sad. I guess a half a century of Soviet control wasn't enough to engender fuzzy feelings for the Russian state. Does Russia's sphere of influence mean the west should let it dictate to former client states? \n\nFinally, with respect to Russia feeling \"threatened by NATO\", **does anyone, Russians included, honestly believe that NATO has any desire to invade?** I just can't believe that one of the Baltic states is just going to wake up one morning and decide to attack."
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6p58vy | what does the title executive producer really do? i see a lot of actors and actresses star in films and they are also executive producers for them. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6p58vy/eli5_what_does_the_title_executive_producer/ | {
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"It really doesn't have a single meaning, but indicates someone contributed to the production in some way without being directly involved in the creation of th movie. In some cases, this is because they originally created characters that appear in later works. This is the case with Buffy The Vampire Slayer. Kaz and Fran Kuzui are given Executive Producer credits for the TV show even though they had no involvement in it, because they were involved in the movie that established the character.\n\nMost commonly, it's because of financial backing. I (along with many others) have an Executive Producer credit for contributing to a Kickstarter campaign, even though I was not involved in any other way.",
"They finance the film, directly and by selling others on investing. Producers are the ones that handle the business aspects of creating a film. So an actor who's listed as executive producer might get that title by investing some money (or doing so by the way they take their pay as a cut of profits rather than straight cash) and may have a part in lining up other investors or talent to join the production."
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2i6pzq | If a pipeline is developed to pump sea water into the desert, would that create a natural precipitation system and irrigate the surrounding land? | askscience | http://www.reddit.com/r/askscience/comments/2i6pzq/if_a_pipeline_is_developed_to_pump_sea_water_into/ | {
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"I think the question here is How long, and much water? If you're pouring only lake amounts of water into the system every year then the heat of the area would probably cause all the water to evaporate, not to mention the sandy earth would wouldn't be useful for keeping water.\n\nIf you pumped a ton of water into a well shaded area with plants that force the earth to retain water, than the water would last a lot longer.",
"I don't remember exactly where I read about it on Reddit, but [Geoff Lawton](_URL_0_) has done some great work in Jordan. He took a ten acre section of desert and turned it into an orchard. Here's a link to relevant video: [permaculture greening the desert](_URL_1_)",
"Aren't deserts formed on the leeward side of mountains? The leeward side becomes a desert because all the precipitation was dropped in the mountains. So you would have to pump that water over a mountain range. Good luck with that.",
"Utah is pretty dry and has a giant salt lake sitting there. I think you'd have to do geo-engineering on a pretty massive scale for this to work through natural evap/precip means. If you're trying to water the desert to grow food or provide folks with water, then you're better off desalinating the water and pumping that into the desert. You will probably create more water in the atmosphere with some amount of agriculture than you would with a much larger body of water since plants are pretty good at dumping moisture into the air through respiration.",
"There was a project the British were considering back in the early 1900's called the Qattara Depression project. The idea was to create canals to allow water to flow downhill into a huge area of the Sahara that is below sea level. They would create an inland saltwater lake, and generate hydroelectricity along the canals. \n\nFishing, transportation and water supply would be revolutionised and it would bring industry to some of the poorest parts of the world. Eventually the lake would turn hypersaline due to evaporation but it would last for a while. It was also believed it would improve the climate of Europe, and turn the surrounding areas into Savannah. ",
"I believe you underestimate the amount of water that falls in a single rain shower. In order to make precipitation irrigate the surrounding land you would need to pump in enough water to both locally evaporate and precipitate while also accounting for ground losses. I'm not even sure you could do this with a reasonably sized river.",
"Many problems with this. First the salt water will contaminate the surrounding land, and any underground aquifers. \n\nAnd while evaporation will occur, there won't be any rain in the surrounding area, all the water vapor will go high up in the atmosphere, and travel hundreds of miles before it condenses to rain.\n\nThe evaporation is already happening in the sea anyway.",
"I would say no.\n\nDeserts are deserts not because of lack of water, but because of their geographic locations which lead to little to no precipitation. Look at a map of the globe. \n\n_URL_0_\n\nAll deserts are generally in the same distance away from the equator or on a side of a mountain. Side of mountain deserts result from the moist air rising up the mountain, becoming cold then raining out and now this dry air passes over the mountain bringing no moisture to the other side. Example, Desert next to Andes in South America. Desert E of the Rockies in US, Desert N of the Himilayas, etc. Just check out any Mountains & Deserts map and you will see that. Deserts on 1 side of a Mountain range. There are also the deserts formed by being near the Tropic of Capricorn or Tropic of Cancer. The Sahara being the most notable of this type, also the Desert in Western Australia as well as the one on the West coast of South Africa.\n\nEven if you put water there, it would evaporate and rain somewhere else because that is how it was created in the first place. We'd have to do some serious irrigation to keep the land moist, but we're not going to alter the weather.",
"Take a look at the green belt in the UAE (United Arab Emirates). They have massive desalination plants that create fresh water for irrigation, to water and feed a tremendous amount of plantlife along the coast and inland. Having lived there for 3 years, they kept saying that the rainfall after it was installed was higher each year than their averages...",
"You may have to be more specific with what you're asking as there are many different answers on here that answer it in different ways.\n\nIf you're asking whether pumping seawater into the desert and letting it evaporate would help the area due to the precipitation. Probably not. Pumping all that seawater(ignoring the power and pumping logistics and the inefficiency of the process) would mean that the seawater when it does evaporate would leave behind the salt. Over time with enough pumping and evaporation this salt would accumulate and effectively sterilise the land indefinitely. You would end up with salt pans covering the desert(this is actually essentially how they collect sea salt). So any fresh water which is gained by evaporating sea water would be falling onto salted land if the rain actually fell there at all. Most of the clouds would fall elsewhere. \n\nIf you were hoping that one area could get heavily salted while neighbouring areas receive rainfall then the answer again is it probably won't work. To get decent precipitation you need decent evaporation, this means you need a large surface area of water to evaporate. Having such a large area would not only be more inefficient (with regard to pumping and power) than the having a more localised desert area to regenerate, it would also mean more rain would fall back into the water source and there is a larger land area surrounding the water source that the rain may fall(effectively dispersing the the rain, less localised rainfall). You would also need to pump a **lot** of water to get any decent amount of precipitation. It would probably be more effective to pump fresh water straight from a desalination plant.\n\nThe other option is that you meant pumping it onto the desert and hoping to create an inland sea or lake(although I don't know that this is what you meant since you state \"precipitation\"). This method assuming you meant the stereotypical sandy desert would not work either. Deserts like this have high ground permeability, very little ground moisture and a very low water table. This means it would be very difficult to retain the water without it dissipating into the surrounding ground. You would need to artificially create a lake or sea environment by digging out an area and lining it with clay or another water impermeable material first.\n\nAll this doesn't even take into account the properties of the soil. Deserts have very little nutrients in them, have little vegetative cover and humus(rich organic top layer of soil). These components are required if you are hoping to try and build a thriving eco system in a desert region, as otherwise many non-desert plants will not be able to grow.",
"The closest example we have to something similar to this is the [Salton Sea](_URL_0_) in California. Its basically the result of the Colorado river being accidentally diverted into a basin. It actually became a pretty popular resort area for some time.",
"Short answer: yes\n\nThis has happened with a river diverted around a shut down desalinization plant on the Arizona / Mexico border. It created salt water marsh, a habitat for endangered wildlife, so for a time the desalinization plant could not open or it would threaten this artificial salt water marsh.\n\n_URL_0_",
"The biggest problem is the built up of salts over time. Eventually, the salt accumulation is so great that plants cant grow even when flooded with this salty water. Salts in soil are a major issue around the world, and removing the built up salt becomes economically futile after a few years. You would need something generating a lot of power to desalinate the water. As of right now, watering vegetables or even palm trees, in the desert from a power plant isn't economically worth while\n\nI have a Masters in Environmental Science and did my thesis work on soils",
"Hmm other civil engineering water projects that worked out great for man and the enviorment:\n\nThe Aral Sea diversions,\nThe Salton Sea\nThe Mississippi/Atchafalaya River diversion\nThe Weyland Canal\nThe Columbia River system...",
"The [salton sea](_URL_0_) in California is a very interesting example of this.\n\nThis lake was caused by accident, they meant to bring some water to the region, but in a heavy rainfall some system failed, and suddenly, they had a lake!\n\nToday, it looks like [this](_URL_1_). Look at the bones and dead fish!\n\nThere have been proposals to pump fresher water into it again, and by circulating it, keeping it from being.... how it is... today.\n\nSo it looks like it can be done, but it needs the constant water flow to keep it going.",
"It'd have to massive. The best analogy I can think of is the Salton Sea in Southern California which was formed by accident when flooding on the Colorado caused water to enter the Salton Sink in huge quantities.The lake has a surface area of almost 1000km2 and it hasn't changed the local environment in the slightest.\n\nThe Salton is shrinking gradually as inflows don't match losses from evaporation. It's long term future is uncertain although the Californian government does have a plan to stabilise its level.\n",
"Because of the earths rotation we have patterns of wind circulation. Pretty much the moist water filled air will condense around the equator and it'll rain there and the hot dry left over air will drift over the 30 degree latitude line and settle there. This is why places at the 30 degree line are dry and no rain ever falls there. \n\nMaking artificial canals would help short term but the water would just evaporate. \n\nWonder what would happen if you made a river all the way through though. ",
"It would take a very very large surface area to significantly impact the precipitation in the region, and I am unaware of any projects that have created such rainfall after filling a dry basin.\n\nIt is well understood that the benefits of pumping large volumes to extremely dry regions are immense. Wildlife returns/appears, tourism can thrive, fishing may become economical, and water becomes available for agriculture. The concern however is the rise in salinity which can 'poison' existing water tables containing freshwater.\n\nThere is a massive project underway to pump water into the diminishing Red Sea, and you may find it interesting: _URL_0_",
"The planet is already 70% covered in water. The pipeline idea could only work if there are highly unusual geographical features to be taken advantage of. As an example look at the skeleton coast in Africa, it is a desert that runs right up against an ocean. The evaporation/precipitation system is obviously too complex for easy ideas.",
"Better yet, they could pump the sea water to the desert, where they have would have put up giant concentrating solar energy collectors which would then desalinate the sea water, which could then be used to irrigate the farm land in the Central Valley, instead of taking water out of the Colorado River and/or pumping it up from the aquifer for that purpose. Then you don't have to rely on a natural precipitation system to do it. ",
"Pump sea water into the desert: cool, but watch out for contaminating a bunch of fresh water aquifers in and out of the area you're trying to help\n\n\nCreate a natural precipitation system: it's more complicated than that, and would depend on the area. \"Sometimes\" would be a good way to answer\n\n\nIrrigate the surrounding land: yes and no, surface flow. In conjunction with getting some appropriate vegetation started it would be more of a yes and less of a no.\n\n\nGeomorphology plus hydrology question with a dash of atmospheric science: it's pretty complex and not the same for all deserts/all places on earth/all local surface or subsurface geologies. \n\n\n\nTl;dr: It could work with the right set up in the right place: it isn't an insane idea just hard to guess the outcome.",
"it would create a useless salt flat. What life is there would be killed The evaporation would fall as rain SOMEWHERE! You could screw up climates globally, and deposit a lot of salt on potentially useful areas of the land. \n\nOver decades, at scale, it could even affect the chemistry of the ocean. "
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1uvtc4 | Deciphering Renaissance Script | This was found at the back of a 15th century painting in Florence, originally from Siena. Can anyone decipher it?
[Image Link](_URL_0_) | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1uvtc4/deciphering_renaissance_script/ | {
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"Do you have a picture with less glare?",
"The painting is supposedly a Sano di Pietra Madonna and Child with Four Saints."
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5yj3fd | How did Catholicism mix/blend/clash with Native American religions and spiritual traditions post–European arrival in the Americas? | If you also know of any good primary or secondary sources on the subject, point me to them! | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/5yj3fd/how_did_catholicism_mixblendclash_with_native/ | {
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"Hi there. I wrote [an answer](_URL_0_) sometime ago that might provide you with the insight you're looking for. Your question is a bit broad, so the linked comment is talking mainly about my tribe. It shouldn't be taken as sweeping generalization.\n\nAdditionally, the book *Removable Type: Histories of the Book in Indian Country, 1663-1880* by Phillip H. Round is a great source of information for the spread of Christianity and the Bible throughout Indian Country. Vine Deloria, Jr., a Native American scholar and author, has a book entitled *God is Red* and details interfaith between Native American religions and Christianity as well."
]
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axbf9y | how does a smartphone determine its gps position instantly, whilst a purpose-built car gps takes minutes to acquire satellites? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/axbf9y/eli5_how_does_a_smartphone_determine_its_gps/ | {
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"Because (for most users) your phone is recieving and processing GPS signals 24/7. You car, however, needs to connect to the GPS sattelites each time you turn it on.",
"Your phone can self-locate using a variety of signals (GPS, mobile data and Wi-Fi in most cases) whereas a dedicated GPS unit typically only uses GPS satellites for location. ",
"It actually isn't done instantly, your phones location tracking system has a tracking filter in it that takes input from the GPS signal and other signals that your phone is receiving such as cell phone towers, wifi signals, etc. It uses all of this to create an area in which you are most likely to be. This takes time though, as it needs to reduce the error for your position, which is why when you first open your GPS app (like Google maps) you see a big blue circle because it doesn't know where you are in that circle",
"It's called A-GPS (either Assisted or Augmented, depending who you ask). A lone GPS receiver does a relatively slow search for the signals it expects, generally on several separate channels in your GPS unit. Once it manages to find one valid signal, that gives it a little bit of information about where you are. That lets it make some smarter guesses about how to find valid signals on other channels. Once it finds a second channel, that gives it an even better idea, and allows even quicker searches. The 3rd lock gives you a single point on the surface of the planet, and you'd golden. Often dedicated units will then lock on several more channels, which increases the accuracy of that point given from 3 satellite locks.\n\nPhones and similar devices have rather inferior GPS receivers (worse antenna, fewer channels). But they don't rely on satellites to narrow down a spot on the planet that you're near. Firstly, you're probably connected to a cell service. Ask your phone which cell tower it's connected to, ask a server on the internet where that cell tower is, and suddenly your phone's GPS can take a hugely better guess on how to find satellite signals, saving all the time a dedicated unit spends on getting it's first 3 locks. Similarly, it can look at the list of wifi networks your phone can see. Again, there are online services that will tell you where a particular wifi router is located, geographically, and that helps confirm your location to a few dozen metres.\n\nObviously A-GPS is handy, and if your handheld/car/ship-mounted unit had internet access, then they could have wifi and cellphone electronics added to them, and get lock much faster. Where it runs into trouble, and it's users run into trouble, is when you're somewhere with bad 3G/4G signal. Suddenly you have a system which is really bad at getting a satellite lock without this help, and either the phone or some apps will then give up, leaving you somewhere remote, without the ability to use google maps to help you get back."
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u3ygh | I often hear that in its entire history, India has never invaded another country, how much truth is there to this? | I guess we could leave Kashmir out of the discussion since it is a hotly disputed region (could really start a new thread on Kashmir but I think thats a whole other can of worms). I also vaguely heard something about a war between India and China but dont know the validity in that.
It would be really interesting if this concept were true since India's history goes so far back, but it would be equally interesting if this 'fact' wasn't true as well. | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/u3ygh/i_often_hear_that_in_its_entire_history_india_has/ | {
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"The conception of a uniform India was the result of invasion in the first place.\n\nIf you mean outside of current borders or past Pakistan or Bangladesh, it's happened before. If you're unfamiliar with just how often, this template showing all the past kingdoms and empires in the area should give an idea: _URL_0_",
"that's a bit like saying Africa has never invaded another country. True, but not a really meaningful statement.",
"Kingdoms in India have all along conquered each other's territories. For most part, there were several thousand kingdoms ruling the different parts of present day India. It was at very few times in history (like during the reign of Asoka Maurya, Mughals,etc.) when most areas of present day India was under one ruler. And then again, when the Brits invaded India, they made it one entity for their administrative convenience. \n\nSo while it is true that the kingdoms in India have not conquered regions outside the area encompassed by the present territory for most part, it is not true that no kingdom ever expanded outside its own. \n\nA few south Indian kingdoms (like the Chola kingdom of South India) have had their kingdoms stretch outside South Asia to countries like Indonesia, Singapore, etc. Indonesia is today a muslim country, but a lot of words they use are still heavily influenced by Sanskrit. Their leader used to be Sukharnoputri. In Sanskrit, it means, daughter of Sukharno (which she is). Their airlines is Garuda airlines, and Garuda is the name of a mythical Hindu bird. \n\nAgain Singapore in Tamil literally means Lion City. But I am not sure if this expansion to South East Asia was done via invasion or merely by cultural means (After king Asoka converted to Buddhism, he sent several emissaries to South East Asia to grow followers there). \n\n\nEDIT : I was just looking deeper into the Indonesia-India relations. Apparently the influence of Sanskrit in Indonesia has got more to do with [ancient trade relations](_URL_1_) and not invasions by kings. Again, the Chola dynasty had strong trade partners in South East Asia and were [not really part](_URL_0_) of the Chola kingdom. ",
"I don't understand how people are missing the obvious here. The city of Goa had been part of Portugal for 451 years. In 1961, India invaded another country's sovereign territory, and annexed that territory.\n\nOne might say, yes, but Goa is properly part of India.\n\nOne could also say Thrace is properly part of Greece, but if Greece suddenly up and invaded Turkey and annexed Istanbul, we'd still consider that an invasion of another country.",
"This actually isn't true; Chandragupta Maurya acquired most of eastern Afghanistan from the Seleucid Empire in a treaty following his conquest of the Seleucid Empire's Indian territory, and possibly a loss in battle, in return for war elephants. The part of what is now Afghanistan was at the time called Arachosia. Between Chandragupta and Ashoka the Great's reigns of the Mauryan Empire, the Mauryan Empire extended control even further west into Arachosia. Greeks had already settled the region in quite high numbers before this conquest, and this is likely to have been the area of the Mauryan Empire containing the most Greeks.\n\nOne of the reasons we know this is that one of the famous Edicts of Ashoka was actually erected in what is now modern Khandahar, and what was probably Alexandria-in-Arachosia at that time. The Edict is in Greek and Aramaic, and is written in excellent Greek considering a) the Mauryans were not Greek speakers and b) there's only so much you have to bother with administrative inscriptions.\n\nI would assume that nobody here thinks Kandahar is within the traditional boundaries of India.",
"The Indian Army was a vital part of the British empire, and participated in campaigns in Africa, New Zealand, and central Asia. In those cases, there were definitely people from the Indian sub-continent invading other places."
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canv7v | Why are biofuels considered less "powerful" than regular fuels? | askscience | https://www.reddit.com/r/askscience/comments/canv7v/why_are_biofuels_considered_less_powerful_than/ | {
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"The common biofuels (ethanol and biodiesel) have lower energy densities than conventional fuels -- i.e. they release less heat per kg, when burned, than conventional fuels. \n\nThis is simply related to their chemistry -- they tend to have carbon-oxygen bonds as part of their structure already (the alcohol group in ethanol, and the ester group in biodiesel). It isn't inherent to the fact that they come from biological sources -- you could make ethanol from an entirely non-biological source, like natural gas, and it'd still have a lower energy density."
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a3ffo0 | The ear is critical to both the auditory and vestibular system. Do any forms of deafness correspond to losses in balance? | Followup Question: If there are any cases, what type of relational link do they have? Correlational? Or some causal direction? | askscience | https://www.reddit.com/r/askscience/comments/a3ffo0/the_ear_is_critical_to_both_the_auditory_and/ | {
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"By the very nature of these symptoms and their respective malfunctioning organs, you can't have deafness *cause* balance loss (or vice versa). You can, however, have a third factor which causes both. [Ménière's disease](_URL_0_), for example, can cause both temporary hearing loss and balance problems. There's an interesting case report here which reports two women with both auditory and vestibular problems caused indirectly by [Ehlers-Danlos Syndrome](_URL_2_). This article abstract mentions [a rare cancer of the nervous system](_URL_1_) which occurs in the vicinity of the vestibular system, and can cause both hearing loss and vertigo as a result (the latter being a balance loss symptom).\n\nHearing loss and balance loss are both quite general symptoms, and it's a bit of a stretch to describe them \"correlational\" or \"causal\", because I don't think there is a study that will have looked at those symptoms in isolation. But, there are certainly things that can cause both to occur, as I discussed.\n\nIf you were referring to complete hearing loss or congenital deafness I'm afraid I've failed you, as the examples I gave tend to be partial hearing loss, and don't generally exist from birth (except Ehlers-Danlos, but in that scenario the hearing problems are a complication of the congenital disorder).\n\n & #x200B;\n\n & #x200B;",
"To answer your question directly deafness does not in itself cause disturbance in the vestibular system, since 2 different structures, and different cells, are responsible for them. They are however connected, small and cramped so there are many cases in which both systems can be affected simultaneously. Tumors, infections of the inner ear, Meniere's disease and damage of the vestibulocochlear nerve are a few. If the problem is in the outer or middle ear it usually only affects hearing."
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"https://www.nidcd.nih.gov/health/menieres-disease",
"https://www.ncbi.nlm.nih.gov/pubmed/27929596",
"https://www.sciencedirect.com/science/article/pii/S1878875018324240?via%3Dihub"
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z8h8l | Please, someone tell me how fiber that completely dissolves in water before ingesting gives the benefits of fiber to your digestion? More questions on fiber.... | This question also leads to the questions...
What is the real purpose of fiber in one's diet? and What are the best sources of fiber? and How much fiber is the right amount?
I sincerely want to know and have wondered for some time. | askscience | http://www.reddit.com/r/askscience/comments/z8h8l/please_someone_tell_me_how_fiber_that_completely/ | {
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"Well there are two types of fiber, soluble and insoluble. The insoluble types of fiber, which are found in most or all plant based foods, like fruits and vegetables, add bulk to your food without adding calories, and they help you make solid stool. The soluble fiber, which is also found in a lot of plant based foods (specially oranges and oatmeal), but much less common, has been known to help lower LDLs and is thought to slow the rate at which food moves from your stomach to your intestines, keeping you fuller longer. The best sources of fiber are fruits and vegetables, though I'm not sure how good metamucil and benefiber and things like that are. If you are eating a well balanced diet with enough fruits and vegetables you should not have to worry about taking extra fiber supplements. Hope that helps.\n\nJust check out the wiki on [dietary fiber](_URL_0_)\n\nAlso, I think this would have been a better question to ask in r/nutrition",
"My daughter is on a large dose soluble fiber for medical reasons. Soluble fiber forms a gel-like matrix in the intestines which helps bulk and soften stool. Her colon doesn't work properly, so she gets constipated and eventually impacted. The soluble fiber helps her poop stick together in a blob, and she takes a laxative that causes colonic peristalsis that pushes against the blob, eventually pushing it out. Without the soluble fiber, the laxative would be less effective, but because the fiber makes it all stick together, it all can come out at once.",
"On a related topic; is there an (achievable) amount of fibre which is too much or could cause more harm than good?",
"While it is soluble in water, try stirring up a glass of Metamucil and then letting it stay on the kitchen counter for an hour, and then check and see what the consistency is like! This gloop provides bulk as well as lubrication and hydration to the intestines. "
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3guk0w | Are there any other species that require long term child rearing for survival like the human? | I think I phrased that right, but typically, animals are born and within hours, days or weeks are able to at least survive.
For a human to survive, the child must be taken care of for years until it is able to fend, feed, and care for itself. Is this seen in any other species?
[EDIT: clarification, a human, left without parents probably up to age 10 or maybe even later, would most likely soon die without care by one or more adults due to the elements, lack of food, predators, etc. Are there other species that *cannot survive* without care for that period of time in their early life? I know some species stay together by choice, others go and come, but they *are capable* of surviving on their own] | askscience | http://www.reddit.com/r/askscience/comments/3guk0w/are_there_any_other_species_that_require_long/ | {
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"Sure, ants, depending on the species some ants spend 1/8th+ of their life going from egg to adult. It greatly depends on the type of any though, some having a lifespan of under 60 days while others its over 10 years.",
"Humans have a very long span between birth and sexual maturity, but they are not the longest. Elephants reach sexual maturity at about 8 years but don't reproduce until they're 15 or so. \n\nI did some searching on the internet to answer your question and came up with some interesting results:\n\nAt the bottom is a link to a database. Just enter the species (or common name) of what you’re searching.\n\nHuman 156 months (13 years)\nGorilla 96 months (8 years)\nChimpanzee 84 months (7 years)\n_URL_2_...\n\n\nBowhead whale 20 YEARS\n_URL_0_\n\nDatabase with this information\n_URL_1_"
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"http://genomics.senescence.info/species/",
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|
2fnope | what exactly is fair use, and how does it apply to quote art? | I want to start making text art posters for quotes from popular films and tv shows and sell prints of them online in order to make a little bit of spending money. [This is an example of what I want to make (note: this is not my work; I am in no way affiliated with the artist and/or seller).](_URL_0_) I was looking at the terms and policies of the website I want to sell them through (Redbubble), and they mentioned that, before you post anything, you should make sure that it complies with Copyright and Fair Use Guidelines. Everything I've read on Google seemed to regard either written works or artwork, and the previous questions on here didn't seem to address what I'm concerned about. So, can someone please ELI5 what Fair Use is and how it works in regards to quote and text art? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2fnope/eli5_what_exactly_is_fair_use_and_how_does_it/ | {
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"Oh. That is definitely not fair use. Fair use is actually pretty clearly defined. Here is the full text of the Fair Use clause in the US:\n\n > Notwithstanding the provisions of sections 106 and 106A, the fair use of a copyrighted work, including such use by reproduction in copies or phonorecords or by any other means specified by that section, for purposes such as criticism, comment, news reporting, teaching (including multiple copies for classroom use), scholarship, or research, is not an infringement of copyright. In determining whether the use made of a work in any particular case is a fair use the factors to be considered shall include— \n > \n > (1) the purpose and character of the use, including whether such use is of a commercial nature or is for nonprofit educational purposes;\n > \n > (2) the nature of the copyrighted work;\n > \n > (3) the amount and substantiality of the portion used in relation to the copyrighted work as a whole; and\n > \n > (4) the effect of the use upon the potential market for or value of the copyrighted work.\n > \n > The fact that a work is unpublished shall not itself bar a finding of fair use if such finding is made upon consideration of all the above factors.\n\nAfter this there are other things that determine what's fair or not, but what you're asking to do is unquestionably not okay. You're making money because people like those quotes. There are much lesser things that are considered violations (like having your waitstaff sing \"Happy Birthday\" to a patron in your restaurant), so this for sure won't fly. ",
"This question is better suited for /r/legaladvice which is a subreddit visited by actual lawyers and exists specifically to have legal questions posted and answered."
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4bn9op | the deaths of tupac and notorious b.i.g. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4bn9op/eli5the_deaths_of_tupac_and_notorious_big/ | {
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" > Is there a generally accepted theory regarding the deaths of Tupac Shakur and Biggie Smalls (aka Notorious BIG)? \n\nGang related\n\n > Who and Why?\n\nCrips killed 2pac, Bloods killed Notorious, because gang related for 2pac, Notorious because retaliation for 2pac\n\n > Furthermore, did being a gangster rapper in the 90s carry inherent risk, or were there specific circumstances that were the catalyst for these particular deaths?\n\nA very high number of rappers were killed in the 90s, so yes, there was an inherent risk for the profession.\n\n > Was it a predominantly East/West issue, or did rappers from other cities (Houston, Cleveland, etc) face similar issues?\n\nCountry wide\n\n > Did some of these rappers serve as proxies for particular gangs?\n\nA very high number claimed and/or associated, be it by proxy, hiring known gang members as security, or they were their friends.",
"2Pac was killed by shug knight. There's a good documentary about his death. The police officers who worked for shug did it probably (one guy alludes to it in the documentary). This seems to be the pretty much accepted answer about 2Pacs death. \n\nShug didn't want 2Pac to leave his label (which he was doing). Pac put out so much shit so that he could finish his contract and move. \n\nBiggie was probably killed by bloods, since they thought the crips killed pac. \n\nDocumentary in question: _URL_0_",
"Huge rap fan here and so I'll try my best to explain.\n\nFirstly, there's no real consensus on who the killers of either person were, nor if either deaths were related.\n\nCorrupt police officers have been investigated into the murder of Biggie and a Crip gang member 'Orlando \"Baby Lane\" Anderson', who Tupac and associates beat down in Las Vegas the same night he died, was accused, but found innocent.\n\nBoth Tupac and Biggie had gang related friends and associates, but neither was part of a specific gang as far as I know. Biggie used to be a crack dealer in Bed Stuy' New York and Junior Mafia may have infact been a gang, but that's not guaranteed.\n\nBeing a rapper wasn't inherently dangerous, it was the \"gangster\" part that added the danger. The East/West issue was more to do with rappers associated with Biggie and Tupac, not as much actual gang warfare. Gangs tended to fight gangs in close proximity, as most people aren't going to fly to the opposite side of the country just to do a drive-by over a vague gang beef.\n\nBeing a gangster at any time carried a risk and if you were a real gangster who rapped, then that didn't change. If you were not a gangster, but still a \"gangster\" rapper, then that could become a problem if people found out you were fake and took issue with that. Some gangsters would be offended someone would pretend to be like them.\n\nThe Midwest and the South didn't have as mainstream of a rap scene as the East and West Coast did in the 90s, despite being arguably more mainstream now than the East and West are.\n\nThose areas did have local scenes though obviously and even mainstream stars (Bone Thugs from Cleveland etc.) but not really a mainstream scene until a bit later on. \n\n\n\n"
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4ea7ee | What would the horizon look like if you were standing on an infinitely stretching and perfectly flat plane? | My understanding is that the horizon is where it appears to be because of the curvature of the Earth, and if the Earth was smaller the horizon would be closer/lower. Obviously on an infinitely-stretching plane the horizon couldn't keep going up, but where is the limit? | askscience | https://www.reddit.com/r/askscience/comments/4ea7ee/what_would_the_horizon_look_like_if_you_were/ | {
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"Actually, the question \"where is the horizon?\" and \"what does the horizon look like?\" are different questions. Let's answer the first question.\n\nWhere is the horizon?\n---\n\nHow do you find the horizon anyway? Suppose you are on a spherical object (like Earth). [Here is a picture](_URL_3_) to make things clear. The variables are\n\n* R = radius of Earth\n\n* H = height of vantage point (e.g., distance from your eyes to the ground)\n\n* θ = viewing angle (i.e., the declination angle at which you see the horizon)\n\nThe farthest point you can see is the point where a line passing through your eyes is tangent to the circular cross-section of Earth. From the diagram, some simple trig shows that your viewing angle is\n\n > θ = cos^(-1)[ R/(R+H) ]\n\nWith H = 6 feet, we get [θ = 0.043 degrees](_URL_2_).\n\nWhat is your viewing angle for an infinite plane? Well, go back to the picture of Earth. Can the viewing angle be any positive angle? Nope. If you look exactly parallel to the plane, then your line of sight does not end on the plane. But as soon as you look down at even the slightest angle, your line of sight meets the plane. So your viewing angle on an infinite plane is always 0 degrees, no matter how high your vantage point is. So if Earth were an infinite flat plane, for instance, the horizon would be pretty much exactly in the same place where it is now (at least for low vantage points). The angle 0.043 degrees is imperceptibly close to 0.\n\nWhat does the horizon look like?\n---\n\nOkay, so what would the horizon look like? For this, we need some physics. For reasons that will become clear, let's also assume that there are no other planets, no other stars, etc. The universe is just this infinite plane of uniform density (and you, I suppose).\n\nAn infinite plane with a constant mass density has a very simple gravitational field. It is uniform on each side of the plane, no matter how far you are from the plane. So if you are right on the surface of the plane, you measure some gravitational acceleration *g*. If you go up a height *H*, you measure the same acceleration. It is a completely uniform field (on each side) that always points towards perpendicularly toward the plane.\n\nSo what? What does this mean? Well, the path of light gets bent by gravity. Even the path of light passing by Earth gets bent, by a very small amount. (Deflection of light by the Sun is a classical test of general relativity.) The same happens for an infinite plane, but the difference now is that it has all the time in the world (or I suppose, distance) to deflect right back to the plane itself. [Here is another picture.](_URL_1_) Light emitted from the plane will eventually curve back to the plane. Yes, it takes a very large distance for this to happen for, say, a gravitational field as strong as Earth's gravity, but that's fine: the plane is infinite. When the light finally is received, it is received at some angle. Our brain always perceives light to have traveled a straight line. So even though the light path is curved, we will perceive the light to have come in from some point in the sky.\n\nUltimately, this means that the entire sky is entirely filled with images of the surface of the plane some distance away. (This is why I assumed there were no other planets, stars, etc. so that light rays do not get obstructed.) In other words, it looks as if the entire world has curved up around you and closed at the top. So it looks like you are actually in some very large spherical planet, for which the \"surface\" is the interior of the sphere. But remember that images above you are really emitted from points on the plane *very* far away. (The point directly above you is infinitely far away.) So as you walk in a straight line on the plane, you won't really see the entire sky rotating around to meet you like you would expect if you were inside a spherical planet. For instance, the point directly above you never appears to move. Try as you might, you will never reach the point where the image directly above you was emitted.\n\nBy the way, what *does* the point directly above you look like? Well, it's where all the points infinitely far away from you are sent by ray-tracing all of the light back. But points infinitely far from you in this world make up the horizon! So instead of *seeing* the horizon exactly where it is now on Earth, you would see the horizon directly above you all crunched up into a single point.\n\n---\n\n**edit:** A few people have (falsely) noted that a 45-degree launch angle maximizes horizontal range and that all the photons start with the same speed. So you end up only seeing some finite portion of the plane around you. This is not correct. That line of reasoning treats light as a ballistic particle in a Newtonian uniform gravitational field. Light cannot be treated in Newtonian gravity: it is neither affected by nor affects gravity in the Newtonian framework. For one clear difference, note that the light paths in a uniform field are not parabolas; they are actually semicircular arcs. \n\nAlso, the oft-repeated statement \"the speed of light is constant\" is simply not true in GR if you take it at face value. The speed of a light signal next to you is always *c*, sure. But the local speed of light for distant light rays, in general, depends on the coordinates. This is not a contradiction; it is an artifact of the freedom of choosing coordinates in GR.\n\n---\n**edit 2:** I have to admit that I have committed a cardinal sin that I absolutely hate to see committed by others: indulging hypotheticals that are sort-of unanswerable.\n\nIf we do everything in a Newtonian framework, then the first part of my response is just fine. The horizon is at 0 degrees, which is barely less than the Earth horizon at about 0.043 degrees for the height of a typical person. For the second part of my response, I did two things:\n\n* used Newtonian gravity to deduce that the gravitational field of the plane is uniform\n\n* used GR to determine the paths of light rays in a uniform field\n\n(Now, technically speaking, there is no metric in GR that has all of the desired properties of a uniform field from Newtonian gravity. There are several candidates though. I just used the simplest of them, which is Rindler coordinates for flat spacetime. But that is a small technicality that doesn't matter too much.)\n\nThere really is no metric that describes an infinite plane of uniform density, at least not one that I can think of or calculate. Perhaps there are some good GR models of such a matter distribution. Anyway, my error of combining the two frameworks of gravity was subtle, but important enough to point out. So take what I said about what the horizon looks like and light deflecting back to you with a grain of salt. There are some unphysical assumptions that go into that.\n\nBetter... just assume that the infinite plane of uniform density is not there. Assume space is just a vacuum, but there is a uniform gravitational field nevertheless. (You can have non-trivial metrics even in a vacuum, e.g., black hole, so this is not a contradictory statement.) If the field is in the *z*-direction, then we can talk about what happens to light emitted at points on the plane *z* = 0. That is a more physical problem that can actually be answered in GR somewhat. Just don't think too hard about *how* we could produce such a uniform field with matter.\n\n---\n**edit 3:** With the second edit above in mind, [see this post](_URL_0_) for my thoughts on concerns about my not taking into account any atmosphere.\n\n\n\n\n\n",
"The other answer is waaaay too complicated. I mean, I noped out quick on that. Let me give you an engineer's answer. Standing on a plane you look around and you immediately have three points. The point you're standing on (or the point directly below your eyes for people who lean like Michael Jackson) we'll call A, the point where your eyes are we'll call B, and the point that you're looking at we'll call C. Line AB will always be perpendicular to line AC which makes the angle at A=90°, and for those unaware the angles in a triangle equal 180°. Therefore, if angle A=90° then angles B and C must sum to 90°. The moment angle B=90° you are no longer looking at the plane because your line of sight is parallel to the plane. Therefore, making the assumption you could see that far and there are NO obstructions, the \"horizon\" on an infinite plane is always always always at eye level in all directions. ",
"This is an excellent question! I recently spent some time thinking about it for a drawing I was doing. It's pretty simple actually!\n\nAnd **the answer is that it would look (basically) exactly the same**! So why?\n\nLet's take some inspiration from computer graphics, where the notion of an infinite place is well defined. In this image the monkey's head is on an infinite plane: _URL_0_. As you can see there is a perfectly normal horizon.\n\nIn order to understand why this is let's do a thought experiment. Imagine you were standing on this infinite plane and looked straight at the horizon. Then you shot lasers out of your eyes. The laser beams would be perfectly parallel to the ground and they would also be in the center of your vision. They would also however appear to meet the horizon as they get further and further away. Therefore the horizon must be exactly in the middle of your vision. Here are some diagrams for reference.\n\n_URL_1_\n\nIn computer graphics that v shape that indicates the viewing volume in the image is called the frustum. You can see that as we move further away from the view, the distance between the ground and the laser becomes smaller and smaller *relative* to the frustrum's height at that point. This means that the two lines will appear to meet in the image, which is the basic concept of a vanishing point.\n\nNote that this also means that camera or viewer is always as tall or high as the horizon line relative to other objects in the image, as long as the camera angle is parallel with the ground.\n\nSo why then does the horizon look like it does on Earth? Well, when you look at the horizon on Earth your gaze isn't perfectly parallel with the ground. It's looking down slightly. How slightly? Well as /u/Midtek calculated, about 0.043 degrees. Not terribly noticeable What if you were standing on an exercise ball instead? Yep, that's going to be noticeable. In fact if you look at an angle tangent to the ball (parallel to the ground), you probably won't even see the ball at all!\n\n***The key difference is that on an infinite plane, it looks same no matter how tall you are but on a sphere it matters how tall you are relative to the size of the sphere.***\n\nEdit: formatting\n",
"I think the book Ringworld works on this subject. At least practical and philosophical.\n\nIf I remember correct the curvature of the ringworld is so small that the people living on it, don't even know that they live on a ring world.\n\nThe curvature is so small that they can't see where the ringworld goes a measurable distance up, so they assume that they live on a flat plane."
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8vualb | How is it possible for an isotope to increase in atomic number when it goes through beta-minus decay? | askscience | https://www.reddit.com/r/askscience/comments/8vualb/how_is_it_possible_for_an_isotope_to_increase_in/ | {
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"Because a neutron is converted into a proton.",
"\"Atomic number\" is the number of protons, ie, the positive charge of the nucleus. So, when you remove a negative charge, this positive charge goes up.\n\nWhat *can't* go up is the atomic *mass*.\n\nSo, for example, when Carbon-14 (6 protons, 8 neutrons, atomic number 6, atomic mass 14, \"isotope mass\" 14.00**3241**) undergoes beta decay, it becomes Nitrogen-14 (7 protons, 7 neutrons, atomic number 7, atomic mass 14, \"isotope mass 14.00**3074**\")\n\nNote that the \"atomic number\" goes up, but the \"atomic mass\" (number of protons+neutrons) stays the same. The actual mass of the nucleus (the \"isotope mass\") drops slightly, since it's ejected a beta particle (and a neutrino) and some energy. "
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3vsovw | What is the neurological reward for learning? | I know that there are reward systems for stimuli, but what does that look like for motivation or reinforcement in learning? | askscience | https://www.reddit.com/r/askscience/comments/3vsovw/what_is_the_neurological_reward_for_learning/ | {
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"Dopamine is the principal neuromodulator involved in motivation and reinforcement.\n\nActions that lead to better outcomes than expected are reinforced by strenghtening synapses. Dopamine is taken by many researchers to signal \"reward prediction error\". That is, the discrepancy between expectation of reward and actual reward.\n\nOperant conditioning is the mechanism through which actions get paired with outcomes. It is believed that for an action to be reinforced, it has to activate the dopaminergic reward/mesolimbic pathway that goes from the ventral tegmental area to the nucleus accumbens. It is also believed that the direct dopaminergic striatal pathway reinforces actions that brings you closer to positive/desirable outcomes (approach motivation), while the indirect pathway reinforces actions that brings you further from negative/undesirable outcomes (avoidance motivation). The amygdala is vital in this process for informing these pathways about what outcomes are good or bad. Damage to the amygdala often leads to apathy and extreme laziness.\n\nSo that's pretty much it for habits. But, as cognitive researchers realized in the 60s, this is not the only or even the most interesting system.\n\nThe habitual system operates thusly: consequence -- > outcome. The outcomes have to be immediately linked to the actions. Think instant gratification. This is, of course, opposite to what we consider to be part of willpower.\n\nThe prefrontal cortex can flip this process on its head: outcome -- > consequences. It starts by identifying desired outcomes and uses knowledge to work out the necessary sequences to lead to said consequences. This is, of course, what we refer to as \"planning\". It can also be useful to differentiate habits and planning as retrospective and prospective control. This is so it becomes obvious that one system is based on past behavior and conditioning, while the other is based on future outcomes (goals).\n\nSometimes there are conflicts between these systems. The retrospective system says (\"eat the cookie\"), while the prospective system says (\"don't eat the cookie\"). The resolution of these conflicts is thought to involve serotonin, as this neuromodulator is heavily involved in behavioral inhibition. Serotonin deficiency has been demonstrated to result in impulsiveness (retrospective dominance).",
"This article gives some idea how it comes about.\n\n_URL_0_\n\nThe key point to note is that it's not just dopamine levels, but dopaminergic activity which creates the joy, the boost, the Flow, the feel good, or the euphoria. \n\nthe boost we get when a good joke is told, largely is reflected by the fact we tell it to others, others to others, and the joke goes \"viral\". The memes of Richard Dawkins are likely what's going on here. The DA increased activity/levels is what drives the re-inforcement, as well.\n\nNicotine, dimethyl xanthines (caffeine, etc.) very likely also act on the DA receptors to some extent. Thus giving that boost, as well as the let down/withdrawal effects if large doses are suddenly stopped. L-dopa is also addictive and is the precursor oral form to DA. This is most often used in Parkinson's treatments. Fava beans also have a modest amount of L-dopa in them, which suggests eating those beans (hummus) rather rewards the user.\n\nIt's not just DA levels, but DA activity which counts.\n\n",
"Others are posting about dopamine, and they are right that it does generate the strongest reinforcement cue, and has been studied the most. \n \nHowever, noradrenaline (locue coereleus) and acetylcholine (medial septum/diagonal band/Meynert) ALSO have patterns of neural activity suggesting they play a role in reinforcement. \n \nLet's not forget that although dopamine does modulate frontal cortex, it does not project to lower sensory areas which also have strongly documented impacts of reinforcement. \n \n"
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20yp2n | are tardigrades from space? | Every animal species on earth appears to have evolved precisely to match environmental conditions.
However, the tardigrade can survive in conditions that could never occur naturally on earth (e.g temperatures just above absolute zero, the vacuum of space, pressures 6x as strong as the deepest portion of the ocean, etc).
How come the tardigrade didn't evolve to match its surroundings like every other life form on earth? Surely it could have evolved to get a less strong cocoon state that involves consumes less energy/resources and more efficiently adapt to its surroundings.
I see only two explanations. (1) a much stronger version of the tardigrade arrived from space (e.g via an asteroid) half a billion years ago and has been evolving since to become a weaker tardigrade better suited to earth's less hostile conditions or (2) there's some evolutionary advantage to having such a strong exterior that is keeping the tardigrade from evolving to match it's surroundings. Which is it? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/20yp2n/eli5_are_tardigrades_from_space/ | {
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" > How come the tardigrade didn't evolve to match its surroundings\n\nIt did. The tardigrade is adapted to deal with drought, and all the rest is just bonus side effect."
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d0uigq | Can reintroduced, formerly native species become invasive? | If for example, a particular species has been extinct in a particular environment, could it's reintroduction lead to further disruption of the ecosystem? If yes, what factors would play into it being invasive? | askscience | https://www.reddit.com/r/askscience/comments/d0uigq/can_reintroduced_formerly_native_species_become/ | {
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"Unless you’re talking about resurrecting mammoths or dinosaurs, no.\n\n “Reintroductions” normally refer to species that were pushed out of a region by human activity in historic times (within a few thousand years), usually much more recently (within a couple centuries).\n\nNow is it possible that habitat is so limited, or prey is so limited (due to modern human activity) that those reintroduced species (particularly a large predator like a Grey Wolf or Brown Bear) won’t thrive in that region anymore? Sure. \n\nIs it possible the reintroduced species will make farmers or other people angry, for a variety of reasons? Sure.\n\nBut ecologically, they’re not invasive, and if the habitat of the region was still intact, a reintroduction would never be considered an invasion—not by science, anyway.",
"Ecologically, a former native species can't be invasive. If the species can't compete with other species in the niche the non-native niche holders would be invasive.\n\nBut there is a chance that the reintroduced species can carry diseases with them that would destroy other native populations. Then it could be considered too damaging to reintroduce."
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2ukk9f | where does the tradition of giving gold, silver and bronze medals to the top three competitors originate from? | Additionally, why those metals and that order? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2ukk9f/eli5_where_does_the_tradition_of_giving_gold/ | {
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"They are in descending order of value throughout the ages. \n\nThat said, it wasn't until 1904 that they were officially the medals for the Olympics (wikipedia). Why? Probably because they are pretty and make for a nice, permanent display of victory. ",
"Gold and silver had been the primary form of money at that time for millennia. Gold doesn't tarnish so it makes an excellent metallic representation of victory."
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3k489a | How do stars fuse elements? How does a star explode? | 1. Where does a star get the energy to fuse elements into heavier elements? Why is it able to do this?
2. Once the star has an iron core, it becomes denser and denser until it explodes. On an atomic/subatomic scale, what is happening here? Why does it explode? Is the explosion a sudden expulsion of density, or is there a hollow sphere created inside the star and everything is pushed out? | askscience | https://www.reddit.com/r/askscience/comments/3k489a/how_do_stars_fuse_elements_how_does_a_star_explode/ | {
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"The energy needed to begin fusion comes from the gravity of the star. A cloud of mainly hydrogen gas collapses in on itself through the force of gravity. Once the inner core gets dense enough hydrogen starts to fuse. Once this has begun, it is self sustaining until the fuel runs out.\n\nBigger more massive stars can fuse elements heavier than hydrogen. Not all stars can do this (so not all of them get iron cores).\n\nA star is basically comprised of two forces in opposition. The force of gravity is pulling towards the core and the fusion reaction is pushing away from it. They're in equilibrium as what is called the [main sequence](_URL_3_). \n\nOnce the hydrogen runs out (it doesn't really all get fused, but not enough left in the density required), and the star is massive enough, the gravitational pressure is great enough to start fusing heavier elements. This puts out a different amount of energy to what was happening before, so a star like our sun would leave the main sequence and becomes a red giant at a new equilibrium.\n\nFor really big stars, ones that can fuse all the way up to iron, die a different death. To understand where the energy from fusion comes from, you can look at the [nucleon binding energy](_URL_0_) of the elements.\n\nNote that ~~iron~~ Nickel 56 has the highest binding energy and decays into iron. Trying to fuse nickel 56 into heavier elements requires more energy than it gives off so it can't be sustained. \n\nSo you can see now that the forces that were previously balanced (fusion and gravity) aren't balanced any more. The self-sustaining fusion reaction isn't occurring but the gravity is still there. Once the iron core is big enough the star begins to collapse in on itself. \n\nThe [electron degeneracy pressure](_URL_1_) of the iron core no longer holds and the core collapses squashing the protons and electrons together into neutrons.\n\nThe outer layers fall inwards until they collide with the core at immense speed, and \"bounce\" off in what is called a [type II supernova](_URL_2_). This bounce can fuse elements heavier than iron for a few fractions of a second, and explodes outwards spreading the outer layers of the star into a nebula. \n\nThe remains of the core is called a neutron star. The cores of even larger stars overcome the neutron degeneracy pressure and collapse further into a singularity known as black holes. \n\nReally really big stars may just collapse straight into its own black hole at the end of its life, without any supernova. ",
"What you are asking about is called [stellar nucleosynthesis] (_URL_1_). There are many different nuclear reactions that can be occurring inside a star, and exact proportion of each will depend heavily on the star's composition, which, in turn, depends heavily on the star's age. The key factor enabling all of those reactions is the combination of incredibly high pressure and temperature, such that nuclei constantly encounter each other with sufficient velocity to overcome the forces that would otherwise repel them. \n\nThe high pressure is caused quite simply by the mass of the star's material, and high pressure of any gas will cause high temperature. When there is enough hydrogen in one place such that it squishes itself together tightly enough to allow the fusion of hydrogen into helium, the star ignites.\n\nThat's when it really gets interesting. You see, all of that mass of hydrogen, were it allowed to compress together fully, would cause an out-of-control reaction that would blow the star apart. Instead, the first ignition of the star begins a balancing process between the inward crushing force of gravity, and the outward pressure from the fusion at the core. This balance gets adjusted as the star ages, causing both expansion and contraction at various points as the energy put out by the core changes based on composition and the relative proportion of the possible fusion reactions (see the link above for more info).\n\nThis brings us to your second question: What happens with iron? There are several models with regards to novae, but the one we're looking at here is [core collapse](_URL_0_) See, iron takes that balance and destroys it. Iron is the first element that absorbs net energy as it is created rather than releasing net energy. \n\nWhy? Well, you can think of fusion energy as a valley with steep sides. The sides of the valley have been carved into steps with walled gardens, so that to get anything from one level to the next lower level, you have to get over the wall first. Once you do, though, it's a long drop to the next level. \n\nHydrogen is at the top of one side of the valley. You manage to throw a ball up over the wall between Hydrogen and Helium, and it falls down. In the process, it has gained net energy...if you had a wheel or something that it would hit on its way down, it would spin the wheel and you could make power. You had to put in a bunch to get it over the wall, but you get that back and then some on the way. You could even use the energy from one drop to get what you need to bounce over the next wall.\n\nSo you do that all the way down into the valley, and you get ready to go up the other side. The first level up on the far side is Iron. You get the ball waaaay up over the wall and...it falls less on the other side than where it started on your side. You had to put in more energy to get it over the wall than you got out. And it only gets worse from there.\n\nIn the core of the star, the fusion energy was holding off gravitational collapse. Once iron is being fused, that energy dwindles. Fusion is still happening, because the pressure and temperature allow it. In fact, as the star collapses inward, the pressure and temperature spike. This causes other fusion reactions to begin to occur very rapidly that were previously occurring slowly or not at all, and those reactions release a *lot* of energy very quickly. The star then blows apart.\n\nHope that helps!"
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"https://en.wikipedia.org/wiki/Main_sequence"
],
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"https://en.wikipedia.org/wiki/Supernova#Core_collapse",
"https://en.wikipedia.org/wiki/Stellar_nucleosynthesis#Key_reactions"
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|
46d9k8 | what is the ultimate goal of pro-lifers who want to repeal roe vs. wade? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/46d9k8/eli5_what_is_the_ultimate_goal_of_prolifers_who/ | {
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"At its core people who oppose abortion oppose abortion. They believe it is the killing of defenseless human life. So while they cheer abortion restrictions their ultimate goal is, as much as possible, to stop the administration of abortion. However they go about it that is their goal. Would they support restrictions if that's what they could get? Yes, like any other group they'll take what they can get. But ultimately their goal is straightforward and unambiguous. There are certainly those who feel that restrictions are all they can hope for, or that abortion should only be banned in certain instances, but by and large people who don't 'support' abortion 'oppose' it.",
"So far everyone here has been talking about this as an issue of whether abortion should be legal or not. Some who want to overturn Roe v. Wade think about the constitutional issue and not the content of the decision. \n\nRoe v Wade was decided because (based on some precedent from prior supreme court rulings) the supreme court judges believed there is a \"right to privacy\" embedded within the articles of the constitution. Basically they believed that based on the 4th amendment (freedom from unwanted search and seizure), the 14th amendment (state cannot deprive individuals of life, liberty, or property without due process), and the 1st amendment (freedom of assembly), they could infer that we have a right to privacy. Some believe that the constitution should be interpreted more literally than others -- that is, that the supreme court should not infer anything from the constitution but rather only rule on what is explicitly written. \n\nTo these people, the Roe v Wade decision was an act of judicial overreach. If the ruling is overturned, then it would (and to these people, should) allow states to each make their own rules governing abortion because they believe there is nothing in the constitution that indicates the federal government has any standing to make these laws."
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[],
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2stu3c | question about war and pow | What would happen if after the announcement of the end of a war if someone say japanese were to kill you or other citizens or military in the pow? would there be a war crime.
also what are laws of war if any? like what is a crime against humanity that you don't do in a war. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2stu3c/eli5_question_about_war_and_pow/ | {
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"Prisoners of war, as far as I know, continue to be prisoners of war in the official sense until they are repatriated, so even with the war officially over, if the POW's were killed, it would still be a war crime/violation of the Geneva Convention (assuming the country in question ratified it, if they didn't it gets a little murky). Even if it wasn't a war crime, it would almost certainly still be prosecuted as a crime against humanity, or simply mass murder. \n\nAs for laws of war, the biggest set is the Geneva Conventions, which put down some basic guidelines, such as fair treatment of POWs, banning the use of chemical and biological agents and banning the use of certain types of ammunition (mushrooming/expanding rounds). Not all countries ratified this convention though, so technically if they didn't, they aren't held to it. However, if that country loses, any mistreatment/violation will still probably be prosecuted. \n\nThere are various ways to get around this, the most famous recent one is that the U.S. didn't classify people they sent to Guantanamo as POW's, so they technically didn't have to abide by/didn't violate these conventions as they didn't apply. Second, Private Military Contractors aren't held to the same standards (Geneva Convention applies to armies) so there were reports of contractors in Iraq using hollowpoints/expanding bullets. As a result, various interests have pushed for closing these loopholes. \n\nSome basic war crimes: \n\n* Executing prisoners\n* Gross mistreatment of Prisoners (like Japan in WWII, I'm betting you are reading Unbroken)\n* Use of certain ammunition (can't find exact wording, but basically hollow points are not allowed due to the injuries they create) \n* No chemical/biological weapons\n* No unfair targeting of civilians (aka, you have to bomb factories, not cities, although this one gets sticky since factories are often in cities) \n* No massacring \n* No human experimentation\n\nnote, these could also be crimes against humanity if a war wasn't going on. "
]
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[]
] |
|
1i7dxm | What happens in your brain when you breathe consciously? | You breathe all the time, even when you're asleep, but you can also hold your breath, consciously hyperventilate, et cetera. Breathing can be under the control of both somatic and autonomic neurons (unlike heartrate, for example).
My question is specifically (but *definitely* feel free to regale me with something cool and related): is there a hierarchy? If you begin breathing consciously, does your breathing "switch gears" from taking orders from a group of autonomic neurons to taking orders from a group of somatic ones, or do the somatic neurons start giving orders to the autonomic neurons, or is it something else? | askscience | http://www.reddit.com/r/askscience/comments/1i7dxm/what_happens_in_your_brain_when_you_breathe/ | {
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" > If you begin breathing consciously, does your breathing \"switch gears\" ...\n\nBrainstem respiratory neurons control automatic breathing. When you begin to breathe 'consciously,' this voluntary breathing is initiated by the cerebral cortex but interacts with automatic breathing via projections from the cortex to the brainstem respiratory centers. For example, corticobulbar (cortex to brainstem) projections suppress automatic breathing during breath holding. The cortex can also directly control breathing via direct projections to respiratory muscles (eg. cortex to phrenic nerve projections).\n\nThus breathing control is not strictly hierarchical but rather a very complicated circuit. You can have lesions that affect voluntary breathing but not automatic breathing, lesions that affect automatic breathing but not voluntary breathing, or lesions that affect both types of breathing, depending on the extent and location of the lesion."
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71j5qa | Has the American prison system always had a much higher percentage of black men than white men? | Hello all! I was talking to a friend about current events, and he made the claim that the percentage of black men in American prisons was much lower in the 1950-60's, and further, that black people were generally better off, at least in terms of wealth, than today. For context, he was using that as an argument that the current prison demographics are not the result of some sort of systemic racism in the justice system, but something else. I don't want to violate the 20-year rule, I just want to know if his claim is true, and if it is, what sort of things other than racism could have contributed to the prison demographics becoming what they were in the 1990's. If racism is a large contributor, I'm curious as to why the prison demographics weren't more unfavorable to blacks in the 50-60's. | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/71j5qa/has_the_american_prison_system_always_had_a_much/ | {
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"According to [this 1991 Department of Justice study](_URL_0_), in 1926 blacks were admitted to prison at 2.94 rate that white people were. By 1986 they were admitted at 5.43 the rate. Time served per conviction has been [pretty equal between the races, and hasn't changed much](_URL_3_). \n\nBut this question is sort of orthogonal to questions of systematic racism in the justice system. We cannot know if either the present or past system is biased against black people solely based on the imprisonment rate. We'd want to know if they are getting equal justice for any given crime. It does seem though, that the higher imprisonment rates historically and in the present are generally reflective of higher crime rates. Here for instance is [W.E.B Du Bois in his 1899 book *The Philadelphia Negro*](_URL_1_) (p. 259):\n\n > It seems plain in the first place that the 4 per cent of the population of Philadelphia having Negro blood furnished from 1885 to 1889, 14 percent of the serious crimes, and from 1890 to 1895, 22 percent. This of course assumes that the convicts in the penitentiary represent with a fair degree of accuracy the crime committed. The assumption is not wholly true ; in convictions by human courts the rich always are favored somewhat at the expense of the poor, the upper classes at the expense of the unfortunate classes, and whites at the expense of Negroes....It has been charged by some Negroes that color prejudice plays some part, but there is no tangible proof of this, save perhaps that there is apt to be a certain presumption of guilt when a Negro is accused, on the part of police, public and judge. All these considerations somewhat modify our judgment of the moral status of the mass of Negroes. And yet, with all allowances, there remains a vast problem of crime. \n\nSimilar findings elsewhere in the country are reported by other authors of the early 20th century, such as Ray Stannard Baker's [Following the Color Line](_URL_4_) or Raymond Fosdick's [Crime in America and the police](_URL_5_). \n\nAnd when looking at the present day, FBI data the racial breakdown of convictions [matches the racial breakdown of offenders from surveying crime victims](_URL_2_).",
"Let’s take a step back here and think about how statistics like these have been used over the past century. The first time these kind of figures became relevant was after the 1890 census, when Frederick Hoffman, an accountant in New Jersey, calculated that blacks accounted for 30% of the nation’s prisoners but only 12% of the population. The conclusion that Hoffman drew – and that many others have drawn, even into the present – is that African Americans have an innate predisposition toward criminality, whether cultural or genetic. \n\nW.E.B. DuBois countered this assertion with a study of black crime in Philadelphia, which he argued was the result of sociological factors – particularly urbanization and industrialization – rather than some innate character trait of black people. Yet the assumption stuck, and even to the present a belief that criminality represents proof and cause of black inferiority remains very strong in American society. (Khalil Gibran Muhammad discusses this at length in his book, *The Condemnation of Blackness: Race, Crime, and the Making of Modern Urban America*; [here’s an interview]( _URL_4_) in which he discusses the 1890 census.)\n\nYet the higher percentage rate of imprisonment among blacks in 1890 was to a large degree the result of a conscious effort by Southern whites to reduce blacks to a captive, servile labor force through the use of the criminal law. Remember that even though slavery was abolished after the Civil War, most white Southerners did not view its abolition as legitimate and did everything in their power to install a racial order in which blacks would once again be a servile laboring class without political rights – essentially slaves in all but name. This was accomplished in part through [the Black Codes]( _URL_0_), which criminalized African-American behavior that was deemed contrary to this order. For example, many states passed vagrancy laws, which required blacks to sign work contracts for fixed periods – if they were found without these contracts, they would be arrested for vagrancy. \n\nOther states and municipalities passed what some call [“pig laws”]( _URL_3_), turning forms of petty theft from misdemeanors into felonies, allowing for heavy terms of imprisonment for blacks who committed offenses as trivial as stealing a pig – hence the name. (And in many cases, it was not even theft; blacks were engaged in work disputes with landlords and employee, and claimed property they believed was rightfully their own – only to be arrested for the same.) \n\nLaw officers were granted a large degree of discretion in enforcing these statutes, and the police were virtually without exception whites with a strong racial bias. What’s more, black prisoners were put to work through [the convict lease system]( _URL_1_), which gave landlords, corporations, states, and municipalities access to very cheap labor, and which played a central role in the industrialization and urbanization of the South at the turn of the last century; about 73% of Alabama's entire annual state revenue came from convict leasing in 1893. So the entire criminal justice system had a vested interest in securing higher rates of arrest, conviction and imprisonment among blacks, both as a source of profit and a means of reinforcing white supremacy.\n\nThe heavy involvement of blacks in the criminal justice system, in turn, fostered racial ideas about their inferiority. As Muhammad puts it:\n > “Defining black criminality through racial and cultural markers of inferiority was at the heart of post-emancipation race relations. Black Codes, Pig Laws, convict leasing, chain gangs, and lynching were direct consequences of inventing new ways of thinking about blacks and using criminal laws, criminal justice practices, and violence to target them—all tracked by statistics, reifying racist presumptions that blacks were an exceptional and dangerous criminal population.” (p. 284)\n\nSo starting this discussion in the 1950s is misleading, in that it fails to account for why this association of African Americans and criminality exists - an association that has its origins in Reconstruction and the beginnings of Jim Crow segregation.\n\n(See also the PBS documentary, [Slavery By Another Name]( _URL_5_), based on Douglas Blackmon’s book of the same name.)\n\n(For more on the use of statistics, crime, and race, see this video: _URL_2_.)\n"
]
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"https://www.ncjrs.gov/pdffiles1/nij/125618.pdf",
"https://archive.org/details/philadelphianegr001901mbp",
"https://www.ncjrs.gov/App/Publications/abstract.aspx?ID=256035",
"https://www.bjs.gov/content/pub/pdf/hcsus5084.pdf",
"https://archive.org/details/followingcolorli00bake",
"https://archive.org/details/crimeinamericaa00fosdgoog"
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"https://goo.gl/gU7r5k",
"https://en.wikipedia.org/wiki/Convict_lease",
"https://youtu.be/2xuo32Z2EMA",
"http://m.video.pbs.org/video/2177178501/",
"https://youtu.be/1z_A1ediUWY",
"http://m.video.pbs.org/show/slavery-another-name/"
]
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|
9v8gzc | how is it possible for a candidate to enter the american election while dead? | I read about this yesterday and am wondering how? _URL_0_ | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9v8gzc/eli5_how_is_it_possible_for_a_candidate_to_enter/ | {
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"The candidates register to run for office long before the election occurs, so that everyone knows who is running and there's time to print up voter information materials, absentee ballots, and that sort of thing. The candidate died less than a month before the election, which is after the set of candidates is fixed, so his name still appeared on the ballots. If a dead candidate wins (as he did in this case), they're treated the same as a person who dies in office.",
"They didn't die until after the ballots had been printed (or at least finalized). Voters were informed, but a lot of people vote for a party rather than a candidate, so at that point people are just voting for the deceased so they can be replaced by someone similar. The people voting for him likely didn't want to see a Democrat in office, so they voted for the dead guy to force a different replacement to be picked.\n\nA friend of mine told me his state (Missouri) once had something similar happen, where an elected official died after the ballots were printed and then won the election. I believe his wife or someone was appointed to fill the position instead, at least temporarily."
]
} | [] | [
"https://abcnews.go.com/Politics/wireStory/dead-brothel-owner-wins-election-nevada-legislative-seat-59026167"
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[],
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oqcdt | what exactly is an ionizer/what does it do? | So I have this really cool [thing](_URL_0_) that is supposed to help w/ people who need lots of light/get bummed during winter darkness/rainy days/etc. It has a negative ionizer on it, and I have no idea why or what it actually does. This is all they say about it on the website: "SunTouch Plus simulates the actual healing effect of a natural waterfall or rainforest, which abound in negative ions. The feeling is said to be absolutely heavenly!" Helpful, right? So can someone tell me more about this mystical ionizing thingy?
EDIT: thanks for the responses. by the way, this thing isn't just an ionizer, it just has an ionizing feature. it's mostly just a really bright light. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/oqcdt/eli5_what_exactly_is_an_ionizerwhat_does_it_do/ | {
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"text": [
"ok ionized air will help dust cling and settle faster, by transferring their electrically charged particle to them. \n\nas far as health goes... pish. "
]
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"http://naturebright.com/?option=com_virtuemart&page=shop.product_details&flypage=flypage.tpl&product_id=5"
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] |
|
2yy5ju | How much of Venus's excessive heat is due to the greenhouse effect vs. geothermal energy? | Would the dense atmosphere of Venus trap geothermal heat or atmospheric friction due to the greenhouse effect as well as solar energy?
How do we know how *much* of that heat is trapped solar energy? | askscience | http://www.reddit.com/r/askscience/comments/2yy5ju/how_much_of_venuss_excessive_heat_is_due_to_the/ | {
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"We know how intense the light striking Venus is and the composition of gases in its atmosphere. The gases have an equation and that determines how well they trap heat. Using this model you can predict the temperature on Venus fairly accurately without even considering volcanic activity.\n\nThis chapter explains the math behind radiative forcing. _URL_0_"
]
} | [] | [] | [
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"http://acmg.seas.harvard.edu/people/faculty/djj/book/bookchap7.html#62386"
]
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|
74exe7 | how did e = mc² become a famous equation? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/74exe7/eli5_how_did_e_mc²_become_a_famous_equation/ | {
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"Aside from being elegant and simple it has a lot of application (nuclear bomb, nuclear fusion, ITER).",
"Einstein was ridiculously famous & Relativity was a huge discovery. E=mc^2 is short and sweet and easy to understand, even if you don't know what it means.\n\nPerfect recipe for a pop-culture phenomenon.",
"It stated that energy could be converted into matter and vice versa. That's a big shocker in physics to the layperson. We all know, or think we know, what matter is - stuff we can hold, or at least contain. But energy appears different. Light, heat, motion, they just feel like they're in a different class of stuff. But Einstein says they're the same, and he can prove it.",
"What's important to consider is that \"E = mc²\" is the culmination of decades of painstaking scientific research by many brilliant scientists. In the end it lead to the theories of Special and General Relativity: arguably the most profound development in our understanding of the universe of all time. \n\n\"E = mc²\" is one of the conclusions Einstein was able to draw, after years of hard work and number crunching for conclusive, airtight proof of all of their findings. It is, in fact, an extremely condensed equation and a mathematical explanation of why this equation is true and the mass–energy equivalence is indeed what it is, would require many, many pages to explain.\n\nSince us mere mortals couldn't begin to understand all the theories and mathematics behind it all, E = mc² became General Relativity's catchphrase as it were. Great marketing, really.",
"Einstein came up with the Theory of Special Relativity which describes how things behave when they are traveling very fast (i.e. close to the speed of light). One of the main equations in this theory is:\n\nE^2 = p^2 c^2 + m^2 c^4 \n(where E is the energy, p is the momentum, m is the mass, and c is the speed of light). If p=0, then you get E=mc^2 .\n\nThis is different from the Newtonian equation E = p^2 /2m which works well for large/slow things. The key difference being that an objects mass (multiplied by c^2) can be considered as an energy.\n\nNow energy can be converted from one form into another, e.g. from potential energy into kinetic energy. So people could see the possibility of getting energy from this rest energy mc^2 term. This is exactly what happens, for example, when we split a Uranium atom (fission) or combine two Hydrogen atoms (fusion). \n\nSo the E=mc^2 equation more-or-less leads to Nuclear power. This is why the equation is important in Physics, as to why it became famous in the general public is down to a mix of wanting something short and sweet and the awe people felt for the atomic bomb in the 40s & 50s.\n\n\n\n\n"
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2szrwj | What is the difference between a hole current and "normal" current with electrons moving? | I was reading an electronics book which stated that an example of a current which flowed the opposite direction of a negative to positive current was a hole current. I understand that in some way the absence of electrons are treated as their own positive charges but I don't see how this is different enough from the normal conception of how electrons flow in a current (have excess negative charge on one end and excess positive charge on the other causing electrons to go from point A to Point B) to cause the current to flow in the other direction (From Point B to Point A).
Edit: Am I fundamentally misunderstanding the Hole current. I hove a conception that holes are suppose to be a "virtual" particle with a positive charge but I still don't see how that is different enough from the way a current full of electrons flowing to the positive end works in a circuit.
| askscience | http://www.reddit.com/r/askscience/comments/2szrwj/what_is_the_difference_between_a_hole_current_and/ | {
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"Current actually involves very few free-flowing electrons. Changes in the electric field propagate at relativistic speeds through carrier media, but electrons themselves don't actually flow at high speeds - [this page](_URL_0_) has some decent explanation for this and even some calculators you can use. A cable with diameter of 4 centimeters has an electron drift velocity of about 1 cm/day.\n\nThe effect of the hole current is to provide the illusion of a positive current via [superposition](_URL_1_) - no current in a small area of otherwise uniform (electron) current is the same as a positive current in that small area with a completely uniform (electron) current.\n\nIf that didn't answer your question someone with more knowledge can hopefully save you/correct me if needed."
]
} | [] | [] | [
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"http://hyperphysics.phy-astr.gsu.edu/hbase/electric/miccur.html",
"http://en.wikipedia.org/wiki/Superposition_principle"
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|
1bu751 | Can the Counter-Reformation be blamed for the intellectual stagnation in most Catholic countries from 1550-1700? | The Counter-Reformation began in earnest around 1540. This is about the time that the Italian Renaissance ended, and Italy would never again take such a prominent role in the intellectual life of Europe. By the late 16th century, Spanish political power began to wane, and it likewise never regained its political and military dominance. Similar things could be said about the Catholic Spanish/Austrian Netherlands compared to Calvinist Holland, and (perhaps) about Habsburg Austria compared to Protestant states like Brandenburg-Prussia. Is the Counter-Reformation the unifying explanation here? Did censorship and the suppression of dissent prevent progress?
The obvious exception here is France. But France was probably the Catholic country least supportive of the Pope, openly allying with Protestant powers in the Thirty Years' War. | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1bu751/can_the_counterreformation_be_blamed_for_the/ | {
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"That's not the case. Counter-Reformation was not only book burning but also a big, positive change in Catholic Church. People saw degeneration of the Church and it was one of the main reasons why Luther and others stood up against it. There were some positive trends even earlier (e.g. stance on slavery, Pius II called it a great crime back in 1462!*).\n\nBut to overthrow your thesis - there were plenty of great catholic scholars in those years and situation in protestant countries you've mentioned wasn't as good as you write. Let me remind you of great Matteo Ricci, a jesuit, founder of Far Eastern Studies. Or a great Polish Jesuit, [Michał Boym](_URL_2_). \n\nBrandenburg-Prussia was a very fragile, weak state before Freidrich Wilhelm II. And even under Friedrich II. it wasn't nearly as strong as Habsburg's empire - they've just had an incredible luck in Silesian Wars. Not to mention the Miracle at the House of Brandenburg. If it weren't for Peter III, Prussia would fell and I think that leaders of unifying Germany would come from other place (maybe catholic Bavaria?).\n\nRemember that this \"book burning\" you've mentioned happened not only in catholic countries. Guess why evangelicals had to flee from England to the New Land? \n\nAlso, the case of some countries is very complicated. Spain and Portugal fell into their own trap - they managed huge colonial empires, this required lots of resources - including intelectual resources and lots of manpower. They had to send officials nad priests to Americas, Africa, Asia, to maintain their huge empires. In those times France didn't have that much land outside Europe and Dutch only traded through VOC - other countries weren't interested in colonies (most of english colonialism was a private initiative). So those resources could have been invested in other things - not administration but philosophy, theology and science. Also, protestant countries were usually more urbanized (I'm thinking especially about Netherlands but also Northern Germany) and it was beneficial for development of their intelectual capital.\n\nI'm more than sure that religion itself wasn't an important factor in diffrences of development of science or philosophy in Europe. There are other far more decisive, like urbanization or geography. Most of countries remained catholic, you only mention some parts of Germany (which weren't that much diffrent from catholic ones) and Netherland as protestant countries which weren't \"stagnant\" in opposition to Spain and Austria. For Polish-Lithuanian Commonwealth years 1569-1648 were a golden age.\n\nBut let's look for some names. [Musicians](_URL_3_) - mainly Italians. [Painters](_URL_4_) - well, we have Dutch/Flemish baroque but lots of them were from the catholic part of Benelux (e.g.Rubens). By the way - why was Netherlands more succesful than Habsburg-ruled part of Benelux? Because it was independent and the capital wasn't a city 2 000 km away with a ruler that doesn't even speak the language of people who are ruled by him. [Sculpture](_URL_1_) - Italian, German, Spanish. Another observation - in cultural heritage aspect, protestants, because of their aversion to opulent churches left us less art than catholics. Also, Catholic Church is probably the biggest patron of arts in the history of mankind. \n\nScientific revolution? Catholics had big contribution, I think it was larger than Jews (Baruch de Spinoza!) or Protestants. Let's count some of Catholics: Coppernicus, Vesalius, Galileo, Matteo Colombo, Blaise Pascal (very religious man, Jansenite - look how long it took Catholic Church to condemn Jansenism despite being an obvious heresy!), Pierre Vernier and many others. Saying that there was some kind of stagnation in catholic part of Europe is an overstatement. \n\n*_URL_0_",
"I think this \"intellectual stagnation\" is more of a historiographical artefact than an actual characteristic of the period. You're pretty much talking about the period between the Reformation and the Enlightenment, which is a bit of a grey area in most people's general view of the history of ideas.\n\nIn reality, this period was critically important in the development of modern politics. This is when old ideas of the purpose and form of politics definitively gave way to modern conceptions, with the invention or reconceptualisation and elaboration of ideas like sovereignty, the state, international law, *coups d'état*, and more. The traditional 'start date' for the modern international system, after all, is 1648 with the Peace of Westphalia, and a while I don't think it's as significant as it's often made out to be, it certainly acts as a good milestone for summing up the period's developments. Most importantly for your question, Catholic thinkers played an absolutely central role in this process.\n\nTwo prime examples. It was Giovanni Botero, an Italian, who first explicitly conceptualised the idea of \"reason of state\", from which the modern concept of the state substantially derives, in his 1589 work *Della Ragion di Stato* -- and it was in Italy that that doctrine first substantially took root. The real magnum opus on this subject is Friedrich Meinecke's *Machiavellism: The Doctrine of Raison d'état and its Place in Modern History*, published in the 50s but only somewhat out-of-date now and still a good introduction, and Meinecke observes that Italy was still 'ahead' of the rest of Europe in this reconceptualisation by a couple of decades well into the 17th century. \n\nFrancisco Suárez, a Spaniard, developed the argument that the state is a creation of human rather than divine law and distinguished between international and natural law in his 1612 *Tractatus de legibus ac deo legislatore*. Hugo Grotius, a much more famous figure in the end, took significant influence from Suárez.\n\nOf course, it is true that the Enlightenment very much originated outside of the traditional Catholic powers (disregarding France, which as you rightly point out is an exceptional case for a variety of reasons). But this isn't because the Counter-Reformation had 'held back' the Catholic powers, whose thinkers contributed to the period's major intellectual developments in very significant ways. Rather, it was more to do with the heady synthesis that came out of combining post-Reformation ideas of the role and nature of religion and secular power with these developments in political thought, which in the first place originated in the Catholic sphere. \n\n(Having said that, even in the Enlightenment one of the most important early figures was in fact an Italian Catholic, Giambattista Vico, whom I took my username from.)",
"One notable field that has incredible development in this time in Catholic areas is anatomy. Northern Italy and France were two of the centers of study. Vesalius is the most famous of the period, creating books containing very detailed anatomical plates, based on real human dissection. His method of inquiry is argued to be one of the things that really helps pioneer the scientific method. He contrasts Galenists who basically treated the works of Galen, a Greek anatomist, as practically infallible. It was kind of funny Galen really does embrace inquiry, but the Galenists will only take the results not the methods. So when Vesalius has human dissections not matching the descriptions of Galen, people just suggest the corpse must be malformed. Galen really based most of his observations on Barbary Apes, many of the muscles don't really match too well. \n\n\nHe did most of his work out of the University of Padua, with good relations with Catholic authority figures. When he stopped lecturing he became the court physician to the emperor.\n\nThere are a lot of fields that really don't upset religious authorities much. \n\n"
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"http://en.wikipedia.org/wiki/Baroque_sculpture",
"http://en.wikipedia.org/wiki/Micha%C5%82_Boym",
"http://en.wikipedia.org/wiki/List_of_Baroque_composers",
"http://en.wikipedia.org/wiki/Baroque_painting"
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27gsfv | does evolution happen at random or does it aim for perfection? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/27gsfv/eli5_does_evolution_happen_at_random_or_does_it/ | {
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"Biological evolution is not aimed at anything. It has no goal.\nChanges in the hereditary material of organisms happen at random and cause variation in a population. Thus, the variation is random. Natural selection preserves those organisms that are fit to survive in the environment. ",
"Evolution isn't sentient. It's just a game of statistics. Given X conditions, Y mutation has more members get to reproductive age than Z. ",
"Mutation (changes in your DNA) is random but how well that mutation contributes to survival and is therefore passed on is based on external factors. \n\nE.G. being able to see slightly better at night for modern, might be useful but as we are pretty much a completely diurnal species who can create artificial light then it probably doesn't contribute that much to your survival so might not end up as a more \"permanent\" fixture in your DNA.\n\nHowever for an owl the ability to see better at night than other owls would probably contribute to your survival in situations where owls are under a large threat from predators or scarce food. It is more likely to get passed on as the owl with that gene is more likely to survive than the owl without that gene.",
"In a vacuum it is random. However, because organisms evolve in *not* in a vacuum but rather in an active ecosystem, there are environmental pressures upon them, such as predators, climate, and so on.\n\nRandom mutations that aid survival against these pressures are, essentially by definition, more likely to survive and pass on their genetics than random mutations that inhibit survival. \n\nThus, over time, you should expect to see a gradual refinement of fitness in an environment, because all the 'less fit' versions statistically tend to be killed off.\n\nHowever, perfection is a nebulous term. Everything else in the environment is also evolving, thus there is no static 'best fit' for an organism to achieve. ",
"The mutations are random. Evolution happens when those mutants survive, and thrive. "
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aphxpb | how do drinks (sodas, canned coffee, etc.) stay mixed together and not separate into their ingredients? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/aphxpb/eli5_how_do_drinks_sodas_canned_coffee_etc_stay/ | {
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"They are mixed at the molecular level, instead of a mixture of chunks. More info: _URL_0_",
"So the seperation between oil and water is due to differing polarity of the molecules: water is very polar, oil is quite non-polar and thus they seek to minimize contact ergo seperation. Soda and coffee drinks usually contain stuff like sugar and caffeine and other small organic molecules contained lots of Oxygens and Nitrogens that will make them fairly polar as well, meaning they will stay in solution in water.",
"Some stuff does separate a bit, like Yoohoo. Things that don't separate are because the ingredients are either completely in solution (like sugar dissolved in milk or water) or because the ingredients make a stable suspension when you get them evenly mixed (homogenized milk is stable because they stir the crap out of it).\n\nDissolving works because it's energetically favorable. Things like sugar and salt have parts of their molecules that have a slight charge imbalance. Water does too, so they like to stick to each other, kind of like little bar magnets. They'd rather hang out with the water than clump together on their own.\n\nIn the case of suspensions (colloids) you have things that don't want to mix, but you get them to because the thorough mixing breaks clumps. For the fat in milk, you stir until the fat ends up in tiny little spheres with water around them. The little clumps of fat want to stay together, and the water wants to stay together. To get the clumps of fat near to each other and start combining back into bigger clumps is a higher energy state, and in general, things want to stay at the lowest energy. It basically takes more energy to get the water (like little sticky magnets) out of the way that's keeping the fat separate.\n\nEDIT: Someone mentioned emulsifiers, which I totally spaced on. That's another thing that may keep a mixture together. Emulsifiers are ingredients that allows mixtures of polar and non-polar ingredients to stay together. An example would be water (polar) and oil (non-polar). Emulsifiers have one end that sticks to polar molecules and another end that sticks to non-polar molecules, so they sort of play matchmaker. Common examples for foods and beverages are egg yolk, mustard, soy lecithin, and various esters.\n\nEDIT2: In my enthusiam for ELI5'ing it I described homogenization as just 'stirring'. While some stuff can remain pretty stable by stirring hard (with like a blender or something), in practice, it works better if you go super saiyan on breaking up the clumps you want to remain in suspension with a more specialized device. As other commentors pointed out, milk is homogenized by forcing it through a small opening under high pressure.",
"a lot of drinks will have binding agents in them. such as mountain dew. it has something called BVO (brominated vegetable oil). not exactly good for you...but they gotta make the drink..look like a drink right?💀",
"Sometimes the molecules stay within the liquid on their own, a suspension, and sometimes chemicals are added to keep everything mixed. A common example of this is an emulsifier. Soap is one of these and allows water and oils to mix when they normally dont. ",
"Most drinks are a mixture of things. Some things are really small, like a sugar molecule. Those things are usual \"dissolved\" or \"in solution\", meaning that sugar likes to hang out with water molecules more than other sugar molecules.\n\n & #x200B;\n\nOther things are bigger, like milk proteins, bits of chocolate, or tiny balls of fat. Then it'ss called a \"suspension\". These can settle over time, but you shake it up, it's usually a good mix. Suspensions are stable for different reasons than above, but the idea is the same. Somethings we need to add things that are called \"surfactants\" to make a suspension stable. Think of these as special molecules with one end suited to your suspended particle, and other end compatible with water.",
"Some things are just prone to stay mixed chemically, like sugar and salts which dissolve in water. Other processes exist for the things that don't dissolve normally. Things like fat have their larger (still tiny to us) bits broken into even tinier particles that do a much better job mixing in. In other cases an additional substance is added that helps them bind or mix in by changing their chemistry a little. ",
"Xanthan gum is a polysaccharide with many industrial uses, including as a common food additive. It is an effective thickening agent and stabilizer to prevent ingredients from separating. \n\nCheck the ingredients and i bet you see it towards the end!",
"If the mixture isn’t naturally stable (like sugar dissolved in water) then various additives (E-Numbers) are used.\n\nCommon stabilisers, which essentially hold everything in place, include agar, gelatin, guar gum, starch, pectin and xanthan gum. You’ll probably find one of more of these in a yogurt or milkshake drink.\n\nSometimes you also need emulsifiers in order to get water and oils to mix. These include lecithin, sodium phosphate and glycerides. Milk naturally contains lecithin, for example.\n\nFor fizzy drinks, the pressure of the container keeps the gas dissolved in the liquid.",
"If it's mountain dew in the US, brominated vegetable oil, I don't know how they do it in the rest of the world where bromine is banned for human consumption.",
"Oil and water don’t mix because their molecules are attracted to themselves and not to each other.\n\nIf you want oil and water to mix, then adding an emulsifier would help them mix together.\n\nBasically what the emulsifier does is it’s attracted to both molecules so it makes them attracted to each other.\n\nSo 2 reasons why drinks stay mixed together are for 1 of 2 reasons:\n\nThe molecules are attracted to each other,\n\nOr,\n\nThey added an emulsifier to force some molecules to be attracted to each other.\n\nTL;DR, it’s an emulsifier. It helps the unmixable mix together ",
"Thermodynamics. There's a million ways you can mix up your molecules and the most \"comfortable\" ways are where there are the most \"microstates\".\n\nSome things don't mix well because there are strong incentives not to, for example oil and water. Similarly to mixing a big bowl of magnets together, they have a preference for how to stack.\n\nMost things don't do this, however, and prefer to mix to maximize the number of microstates available to the mixture.\n\nIt's not just random chance. If you shuffle a deck of cards a hundred times, you will sometimes get patterns of cards forming straights and flushes. But you can mix a liquid mixture once a minute for an infinite number of years and you will never separate the components by chance. The liquid prefers to be that way.",
"Gum Arabic for the longest time was the main emolsifier used in the soft drink industry to keep everything suspended in the liquid. The largest exporter of gun arabic was sudan. The government of Sudan had ties to the one company in charge of exporting Gum arabic and funneled that money into genocides against first South Sudan and then Darfur. And the industries that purchased Gum arabic from Sudan remained silent. They even changed the name of the type of gum it was so as to not raise attention to the fact that they were doing business with Sudan. When the US publicly criticized Sudan back in '08 or so, the foreign minister held up a bottle of Coke at a press conference and threatened to cut off the world's main supply of gum Arabic. At one time, Sudan supplied 80% of the world's gum arabic."
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cecur1 | What kind of fuel is used for rockets in space? | Since there is no oxygen in space, what kind of fuels are used for moonlandings etc.? | askscience | https://www.reddit.com/r/askscience/comments/cecur1/what_kind_of_fuel_is_used_for_rockets_in_space/ | {
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"Liquid hydrogen and liquid oxygen are common propellants. Liquid oxygen is generally the most common oxidizer but there are more exotic mixtures like UDMH/red fuming nitrous acid that can be used. (In that case the UDMH is the fuel and RFNA the oxidizer.)",
"Liquid oxygen is a common oxidizer with liquid hydrogen or refined kerosene for initial stages, but in space thrusters are desired to be simple - standard chemical rockets have minimum throttles and require igniters.\n\nA work around is hypergolic fuels, which ignite spontaneously when the fuel and oxidizer mix, are frequently used for late stages and maneuvering thrusters. These fuel types include dinitrogen tetroxide and hydrazine. The lunar lander used hypergolic fuels for ascent and descent.",
"There are several different advantages we want from rocket fuel:\n\n* The exhaust (burned) gas must have a low molecular weight. This will give a better exhaust speed and, therefore, require less fuel for the same manoeuvre.\n* The fuel must fit in a small tank. Tanks are heavy, we want to get rid of them. (In fact, that's why rockets drop stages.)\n* The fuel must be stable at room temperature and not boil off. Not only this will be easier to manage, but also require lighter tanks due to the lack of insulation. Also if it boils off quickly then it will not be able to stay in a satellite's tank for a long time.\n* It must not be toxic, or explode by shock.\n* It must be cheap because a lot of it is needed for a single launch.\n* It must be easy to ignite. Ideally, just throw it into the nozzle and let it start burning on its own.\n* It must not require oxygen to burn (basically your question in the textbox)\n\nUnfortunately, **no fuel we know of combines all of these advantages.** It'd be awesome if one did, wouldn't it?\n\nOkay, since it is what you were asking about, I'll start by the last point. Fuels that don't require oxygen (or any other kind of oxidizer) are called *monopropellants,* as opposed to *bipropellants* which are a combination of a fuel and an oxidizer (usually liquid oxygen but there are others) in separate tanks that combine in the rocket engine. Monopropellants usually start burning because there is a catalyzer, so they also don't require an ignition source. Examples of monopropellants:\n\n* Hydrazine. When catalyzed it decomposes into hydrogen and nitrogen. This reaction releases energy so it heats up, but also, hydrazine is liquid while the nitrogen and hydrogen are gases. It can be stored at room temperature. Disadvantages: it's expensive, extremely toxic, and has a low exhaust speed so you need a lot of it. It's commonly used for attitude control (rotating in space) because it doesn't boil off so it can be stored for years in a satellite, and provides *instant* thrust when you throw it into the engine, so it allows for precise control.\n* Hydrogen peroxide. When catalyzed it decomposes into oxygen and water vapor. It's extremely corrosive and has a bad exhaust speed, so it's rarely (if at all) used. (Fun fact: it has the particularity that it can be either a monopropellant, or an oxidizer, see below).\n\nStorable (non-boiling off) bipropellants:\n\n* Unsymmetric dimethil-hydrazine (UDMH for short): can be oxidized with either nitric acid, or dinitrogen tetroxide. The combination is hypergolic, which means it starts burning instantly when the fuel touches the oxidizer without any spark or catalyzer to ignite it. It also has a good exhaust speed. Disadvantages: expensive and extremely toxic. Common in Chinese launchers. Also, the space shuttle attitude control used UDMH to rotate in space.\n* Aerozine: it's a mixture of hydrazine and UDMH. Its properties are very similar to UDMH. Was used in the moon landings with dinitrogen tetroxide (to answer the second part of your question).\n\nNon-storable bipropellants:\n\n* RP-2: highly refined kerosene. The fuel itself is storable, but it must be oxidized with liquid oxygen, which is moderately cryogenic (must be kept at low temperatures). Good exhaust speed, non-toxic, and cheap in countries that have petroleum. Very common in Russian launchers. I've seen experiments to oxidize it with hydrogen peroxide instead, but am unaware of any real applications of this combination.\n* Liquid hydrogen oxidized with liquid oxygen. It has the best exhaust speed of commonly used fuels. But it's expensive, very cryogenic, and low density, so it requires very big tanks with a strong thermal insulation. Common in NASA and ESA launchers (e.g. Space Shuttle main tank, Ariane 5 upper stages).\n\nSolid fuel:\n\nThis is a special case, technically a bipropellant, but in practice a mono. Basically the fuel (usually aluminium power) and oxidizer are mixed in a gel of fine grains. It doesn't burn as long as you don't ignite it. Its greatest advantage is the density: you can fit a lot of it in a small tank. Also stable at room temperature. Once you ignite it, it keeps burning until you run out of it, and it also cannot be throttled. For these reasons it's only used for launching. Very common in rocket boosters like those of the Space Shuttle or ESA's Ariane 5.\n\nAt the beginning of the space era they tried other kinds. The Russians did a launch using lithium as fuel and fluorine as an oxidizer. This has been proven to have to best exhaust speed so far. But since lithium had to be melted at a high temperature, and fluorine had to be kept very cold, it was a design puzzle. Even worse, fluorine is extremely toxic, can explode by shock, and is very expensive. Needless to say, they didn't try this again.",
"Even rockets flying in atmosphere don’t use the atmospheric oxygen for combustion, they use a fuel and an oxidizer. A very common pair for first stages is kerosene (not your average kerosene, it’s been refined specifically for use in rockets) and liquid oxygen. Liquid oxygen is also burned with a number of other fuels, like liquid hydrogen or liquid methane, or as another user mentioned UDMH and IRFNA, or Aerozine 50 and NTO. Liquid hydrogen and Aerozine 50 are probably the most common upper stage fuels. Hydrazine is also used in control thrusters."
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2r789x | how do companies that buy & re-sell other people's debt make money? | Say, a call center is open specifically to buy and sell debt. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2r789x/eli5_how_do_companies_that_buy_resell_other/ | {
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"You owe $7,000 to Bustass Bank, but quit paying for five months. Your debt is now worth substantially less since it is nonperforming, and may be sold for $2,000 at this point, and more like $500 after 270 days. They then harrass you to pay or sue you for the full debt. If they paid $500 and collect the full $7,000, they win.",
"They buy up debt for cents on the dollar. Take for instance some debt that has been recently charged off by a bank. It isn't fiscally profitable for the bank to try and collect on it because they don't have or want to maintain a huge collections center. But they could sell it for ten cents on the dollar for someone else to collect. In the case of $1,000,000 of debt, the bank gets back $100,000 and the debt buyer gets $1,000,000 to try and collect.\n\nAs long as they can keep their margins above 10% it is all profit, minus whatever overhead they are incurring.",
"I get that they are \"bottom feeders\" but to be fair if someone doesn't repay their debts (of at least the principle amount) they ultimately stole that money. Thanks in advance for the downvotes ;)"
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i1wd3 | How much net energy, in relative terms, does an individual atom contain? | Are we talking like a stick of dynamite or like a Duracell battery? | askscience | http://www.reddit.com/r/askscience/comments/i1wd3/how_much_net_energy_in_relative_terms_does_an/ | {
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"Well, let's look at a single proton first. Let's say you have a lone proton that is completely stationary. A proton has a mass of around 1.67×10^-27 kg. E=mc^2 leave us at around 1.5X10^-9 J. This would be enough energy to power a 60 W light bulb for .000000000025 seconds.\n\nIf you just look at the rest mass of an atom of Lead-207. Pb-207 has 82 protons, 82 electrons, and 125 neutrons. This totals out to about 3.11X10^-8 J, so barely anything in a single atom.\n\nThese aren't big numbers but take into consideration that a gram of Pb-207 contains about 2.91X10^21 atoms in it. That means it has about 9.05X10^13 J of energy in it. The bomb dropped on Hiroshima gave a yield of about 6.5X10^13 J. About 0.6 g of U-235 was actually converted into energy, compared to the 65kg of Uranium that was in the bomb.\n\n**tldr** A single atom of lead could power a 60W light bulb for about 0.00000000052 seconds. However, take a gram of it, and you have more energy there than the bomb dropped on Hiroshima."
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2m0iwb | Is the genotype a phenotype? | I can select for specific individuals with a desired genotype by establishing their genotype in the lab and then removing all of those individuals who don't have the correct genotype. This even though selection is traditionally supposed to act on a phenotype.
Does this mean that an organism's genotype is in fact a phenotype? Does this distinction matter at all when discussing the practical theory of evolution, mathematically or otherwise? I'm interested if such a seemingly philosophical question might have actual implications in the history of the understanding of evolution. | askscience | http://www.reddit.com/r/askscience/comments/2m0iwb/is_the_genotype_a_phenotype/ | {
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"Those terms were coined about a century ago, back before we had any idea how genetic information was transmitted. Back then, the only reliable way to get the genotype of an animal was after the organism had given rise to a few generations of controlled breeding. \n\nThere are exceptions to this, though. Imagine you have a simple inheritance gene with a recessive allele (the classic, unrealistic yellow peas thing). If you see an organism with the phenotype associated with that recessive gene, you can immediately derive some partial and useful information about its genotype. You know it has two \"yellow\" alleles, its parents had to have certain alleles, and its progeny will have certain patterns. It's not complete, but it is useful.\n\nBut that was the exception, not the rule. Originally, \"genotype\" referred to the genealogic information about an organism. It was information outside of the individual organism. Phenotype referred to physical characteristics, things that were measureable.\n\nToday, the meaning of \"phenotype\" hasn't really changed, we're just able to measure a lot more stuff than just the color of the pea. Now, we know that the DNA sequence AAGATTAGGAA is associated with this allele, and if we see it, we can make predictions about the parentage and progeny.\n\nAs a result, the meaning of \"genotype\" is now often used to refer to \"what alleles this organism has\" as a kind of shorthand. This isn't necessarily a bad thing, but it can be a source of confusion when using the old definitions and rules.\n\nSo try to think of genotype in its original sense; information outside the organism, something somewhat abstract. Genotype is something we assign to it. We can derive it from phenotype, but it is separate.\n\nSo in answer to your question, the genotype is not a phenotype. But the PCR you do to genotype your animals is also not a genotype. It's a phenotype from which you can derive partial (but useful) information about the genotype. "
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a12yex | Were famous, named, weapons common and sought after in medieval Europe? | There is a popular fantasy trope of exquisitely made weapons being named and desired by knights and rulers (see excalibur, and any of the pile of valerian steel swords in asoiaf)
Though in reality the only one I've really heard of in the west was *stories* of excalibur. In the real world, in high and late medieval Europe, were there *actually* well known named weapons floating around being sung about and sought after by warriors and monarchs? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/a12yex/were_famous_named_weapons_common_and_sought_after/ | {
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"Outside of the Arthurian and other legends? Not that I am aware of. Swords in medieval Europe were essentially... not really disposable, but it was well understood that they would be damaged, require care and maintenance, and eventually break or wear out. Especially if they were used a lot.\n\nNow, the interesting part is that with care and storage swords CAN last a long time. Especially if you are able and willing to replace different pieces of them, but not necessarily the whole sword at once.\n\n So what this led to is that at some points during the medieval period swords were very expensive, and at other later points, there were so many of them hanging around that you couldn't give them away depending on where you were in Europe at the time.\n\nThe Arthurian legends are, as far as I know, the main source for all of the popular media in the west about seeking after a particular sword. However, they are NOT the ONLY source.\n\nThere are other legends as well. Beowulf's sword Hrunting. Other legends of powerful objects as well. Manannan Mac Lir gave Fragarach to Lugh.\n\nSwords have long been a symbol of authority as well as a weapon. Part of this is because of the type of weapon they are, and part of it is because of who had them at various times.\n\nNow, as to what warriors tended to value in swords, now that was rather different. Warriors needed a weapon. And so they valued good craftsmanship and good materials.\n\nAnd what people thought the \"best\" of those things were, tended to vary based on where you were and when. But it is interesting to note that the places in Europe famed for their metalwork in the Medieval period also became major centers of trade.\n\nSo in Spain you have Toledo steel, in the Germanic states you have Solingen Swords, in Italy it was Milan that held supreme. In Britain, it was either imports or for local make you wanted London's Worshipful Company of Cutlers.\n\nAll of this is before we get in to the discussion of various developments of metallurgy at various times. For that, suffice to say that one of the main things that made the Medieval centers for sword and knife making as well known as they were was a very good control of the carbon content of their iron as they worked it in to steel. As well as knowing, at least somewhat, about certain trace metals that can make steel more suitable for most common applications at the time.\n\nA lot of legends about swords that can cut through anything or otherwise are just better likely have their origins in the fact that metallurgy was not developed everywhere equally all at once. It developed over time with individual discoveries turning in to cultural traditions long before scientific methods or understanding could be applied. So if a soldier was traveling in a distant land and ran across metallurgy far superior to that in their own land, it would seem to have magical properties to their eyes.\n\nRemember that the scientific method of exploration, at least the way we frame it now, dates to the 16th century and a lot of differences in knowledge prior to that were attributed to everything from divine favor to magic to whatever the flavor of the month was. "
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6cogf6 | why do people steal iphones if the fbi had such a difficult time unlocking the phone of the san bernardino shooter? | If the fbi struggled wouldn't it be even harder for the average mugger?
The iphone is pretty much useless if you cannot unlock it. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6cogf6/eli5_why_do_people_steal_iphones_if_the_fbi_had/ | {
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"Depends on if you want the contents on it or not. I'm sure that the FBI wanted all of his information on that phone when they opened it. Someone who steals your phone can just erase everything and wipe it and use the hardware. ",
"I don't think that thiefs are in need of the data that is stored on the iphones (or any smartphone for that matter). While FBI needed the data that was already in the phone, all thiefs have to do is restart the smartphone and its back to its basic settings. And the only way FBI would be able to get access to the iphone is if Apple created a key made specifically to unblock owned iphones, which is susceptible to being leaked and thus give anyone access to all of the iphones. ",
"The mugger doesn't care about obtaining the data, and doesn't need to use tools that conform with US constitutional protections for the accused. The FBI needs both. \n\nThe mugger wants a phone that can be resold, so they're happy with a factory reset. That process can be done [without the passcode](_URL_0_). The FBI was much more interested in the data on the phone than the phone itself, so they couldn't just perform a factory reset (that would flush the data they were so interested in obtaining). ",
"I want to correct a few misconceptions people seem to have here. Yes, it is possible to factory reset an iPhone without the passcode to unlock it. HOWEVER, when the original owner sets up their iPhone (either from scratch or after a restore) they sign in with an iCloud account/Apple ID, and a feature known as Find My iPhone is generally enabled by default. Why is this important?\n\nIf the phone is erased while Find My iPhone is turned on (it can only be turned off with the Apple ID password), the next time it goes through initial setup and contacts Apple's servers to activate, it will enter a state of Activation Lock. In this state it will ask for the Apple ID and password that were originally signed in, and will not proceed without it. This will render the phone essentially useless except for parts, which is still not bad. Original Apple parts can be valuable in the third party repair market because Apple does not sell them to anyone else, and reserves the right to refuse service if third party components are found. Take an original battery at $79 or an original display at $129-149, for example.\n\nCriminals are slowly realizing this but iPhone users are still being robbed because, well, there are still some that haven't gotten the memo or want to take the risk in the hope that Find My iPhone is turned off by an oblivious user. And smart criminals generally don't go around purse snatching, but rather participate in more ambitious thefts, so the ones stealing iPhones are probably scraped from the bottom of the barrel anyway."
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22e0m6 | Why are people of Latin America considered Latino / Hispanic while Filipinos are not? | The Philippines were colonized for roughly the same amount of time as South and Central America, yet we don't call people of Filipino descent Latino or Hispanic. Filipinos are often just called Asian. | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/22e0m6/why_are_people_of_latin_america_considered_latino/ | {
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"Spain and Portugal were big on colonizing South America. The Philippines was colonized by Spain because it is a necessary and strategic location for trade with the Far East, especially the spices from India and Indochina and the Porcelain from China. The Philippines politically was of minimal importance to Spain because Mexico (and the surrounding territories) was a much more important colony. In fact, Spain ruled the Philippines through Mexico, not directly, by virtue of the Viceroy of New Spain.\n\nHence, the Spanish influence is much greater in Central and South America that it ever was in the Philippines. While it can be argued that Filipinos are indeed hispanic, they are less so than the Spanish Colonies in the Americas.\n\nSource: Teodorico Agoncillo, History of the Filipino People"
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12hciq | Is there any science to "ridding your body of toxins" via exercise/sweating? | I recently started taking hot yoga classes at a local studio. They crank the temp up to around 95 degrees for the 90-minute workout and use a lot of language about how the heat helps you "sweat out the toxins in your body" and things like that. Yoga class aside, I've heard this sort of language used in regard to other strenuous exercises. Is there any basis for this? If so, what toxins would they be? Can you give a layman's breakdown of what the "ridding" process is? | askscience | http://www.reddit.com/r/askscience/comments/12hciq/is_there_any_science_to_ridding_your_body_of/ | {
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"The purveyors of such beliefs never actually define what exactly these toxins are or why their preferred method would get rid of them. It is, however, exactly the sort of vague health claim that allows one to avoid potential trouble with government regulating bodies in many countries, conveniently. \n\nOf course, I'm not claiming that many practitioners don't actually believe it. At any rate, there's nothing to this claim, no evidence has ever been presented in favour of it, and it doesn't make a lot of scientific sense.",
"No. It is, however, great at purging your body of water and electrolytes, causing you to feel drained and exhausted, and therefore fooling you into thinking you've gotten a harder workout than you really have.\n\nYou've already got a couple of organs (liver and kidneys, for example) whose *sole purpose* is to help remove toxic substances from your body. They work pretty well on their own as long as you don't fuck them up.",
"For the most part, the toxin purged is sodium.\n\nAmazes me to see these \"toxin extraction\" patches advertised where they suck toxins out of the body through the feet. If you're gonna use a transdermal process, what sense does it make to use thickest skin in the body?",
"No.\n\n[This]( _URL_0_) says that such a small amount of anything defined as toxins is present in sweat that it's better just to make sure your kidneys and liver are healthy.",
"Not really detox, but fasting has been shown to promote autophagy in a number of studies:\n\nA primer (see the section on autophagy): [The Health Benefits of Intermittent Fasting](_URL_2_)\n\nStudy: [Short-term fasting induces profound neuronal autophagy.](_URL_0_)\n\nStudy: [Mitochondrial degradation by autophagy (mitophagy) in GFP-LC3 transgenic hepatocytes during nutrient deprivation.](_URL_1_)",
"Related question: I've always been told that when withdrawing from alcohol, the copious sweating is due to my body \"sweating\" the alcohol & associated toxins out of my body. Is there any truth to this? If not, what causes people to sweat so much during alcohol withdrawal?",
"Im skeptical myself, but I am seeing a lot of \"no you are wrong that is just stupid alternative medicine garbage\" rather than any actual \"here is some studies that show heavy metals are not excreated in appreciable amounts by sweat.\n\nIn fact the only cited articles I have seen so far are posted are those suggesting that heavy metals ARE excreated in sweat, and in some cases at levels higher than urine (though they leave out the bile excretion a huge factor in heavy metal excretion).\n\nSo how about instead of just saying \"your dumb because that sounds like herbal remedy mumbo jumbo\" we start providing some facts. Medicine is constantly changing folks. A lot of traditional herbs end up having useful medical active ingrediants (though a lot more dont)."
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g5soj | What is an acceptable definition for life -- in terms of distinguishing something from a living organism or not. | How do we define if something is a living organism or not? I've read a few definitions and they usually include a short list of qualities, but they don't ever match completely.
Wiki defines it as: "Living organisms undergo metabolism, maintain homeostasis, possess a capacity to grow, respond to stimuli, reproduce and, through natural selection, adapt to their environment in successive generations."
* not all living things reproduce. Infertile animals are born all the time, but that doesn't make them any less alive. Colony drones (bees, ants) don't reproduce either, but they are alive.
* adapt to environment through successive generations shouldn't be a requirement, it just wouldn't spell well for the species' longevity, but can't be used to say that a member of the species isn't a living organism.
* respond to stimuli -- this one is debatable because some organisms respond only as a result of internal chemical reactions. Does grass or amoebas respond to stimuli? Sure, if you concede they don't do it consciously.
If you remove reproduction and adaptation from the list of requirements, some non-living things, such as stars and planets, meet the definition of a living organism -- stars can even reproduce by ejecting gas or going supernova.
If we do come across extraterrestrial entity that doesn't match our common perception of a living creature, how should we define if it is alive? Assume it can't tell us it's alive. | askscience | http://www.reddit.com/r/askscience/comments/g5soj/what_is_an_acceptable_definition_for_life_in/ | {
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"That wiki definition seems pretty good actually. \n\nYou can't really remove reproduction. Just because some populations have members that don't individual reproduce for whatever reason, that doesn't mean that that specific type of organism doesn't reproduce. \n\nI'm not sure I understand why you trying to throw out adaptation. \"It just wouldn't spell well for the species' longevity\", doesn't make sense, because without adaptation, that species wouldn't be in that environment anyway. ",
"There's always endless debate about this topic, particularly when you consider some things that share some properties and similarities but also lack some, like viruses. There is no absolute definition of life, just a general set of properties that work for us and more or less all things we recognize as life would have most if not all of these properties.\n\n > not all living things reproduce. Infertile animals are born all the time, but that doesn't make them any less alive. Colony drones (bees, ants) don't reproduce either, but they are alive.\n\nYou still recognize they are alive though despite not fitting your criteria. Why? They are members of a species that as a whole have the capability to reproduce, and share similar properties as other thigns considered living.\n\n > respond to stimuli -- this one is debatable because some organisms respond only as a result of internal chemical reactions. Does grass or amoebas respond to stimuli? Sure, if you concede they doesn't do it consciously.\n\nAll organisms respond only as a result of internal chemical reactions. Living things from single-celled bacteria to complex animals all sense stimuli through chemical and physical processes, and we're not any different. Is your response to seeing these words not the result of a photo-isomerization reaction of a cis-retinal molecule that activates the covalently bonded rhodopsin molecules, which as a GPCR begins a signal transduction cascade that causes neurons to change ion flux across the cell? The distinction of \"conscious sensation\" is an artificial distinction that doesn't really play a role. Living things all respond to external stimuli to some extent, and these are all guided by physical and chemical processes, not \"consciousness.\"\n\nIn the end, all of this is just semantics and artificial definition, and such strict definitions rarely cover every possible circumstance. All of these are just descriptive, a result of the fact that we have studied living things and recognized their properties and summarized them post hoc.\n\nWhat people should care more about is the actual properties of what you are looking at. It doesn't matter if you define viruses as living or not, the point is to study how they work and what they do. If we find something that resembles life in other planets, then we study them. What artificial label we place on them doesn't change what they are. If we need to change our expand our definition later if we find something interesting then it can be done. ",
"It's tough to define, and any attempt to provide a complete categorical definition is probably going to either include non-life or exclude life. \n\nMy favorite definition for many years came from my bio prof in college: \n > \"Life\" is any self-contained system which increases entropy outside itself in order to decrease the entropy of the system. \n\nThis might be argued to apply to man-made things like refrigerators, but it's cleaner than behavioral things like \"reproduction\" and \"response to stimuli,\" which are highly subjective.",
"There is no fully acceptable definition of life that I am aware of. Every definition I have heard either includes some things that are certainly not alive (crystals and fire are classic examples), or excludes things that are life.\n\nEven the wiki definition you quote: viruses don't have their own metabolism, and most don't maintain anything that even resembles homeostasis.\n\nIf you take out those two so viruses are included, fire comes in. Fire can grow (obviously), respond to stimuli (wind, water, etc), reproduce (flying sparks), and even adapt (new fuel can lead to a hotter or cooler fire that is better suited to burn that material). Very simplistic, but it fits. If we include the necessity of reducing local entropy and/or storing information, crystals can work. \n\nEven subjectively it's hard. A bacterium is certainly alive. A virus is alive. Is a prion alive?\n\nThis is a big problem in life sciences; it is similar to the species debate (how do you define a species?). We ran into it in the last decade with immunology. \n\nWe want to make things clear cut so we can pigeonhole them. But biology doesn't work that way; it is one big mottled gray mess with the occasional relatively black or white patch. We intuitively know that a Great Dane and a Shitzu are both dogs, and that a mountain lion and a bobcat are two different species. But why?\n\nIf it's just gene exchange, does that make my dog (in the US) of a different species than a dog in England? What about lateral gene flow? Bacterial genes can flow into the human population, viruses live by putting their genes into your genome, and it can get into the germ line. Are we now the same species as Staph and CMV? When you take into account that things like influenza virus can pick up genes from one host and carry them into another, it mixes up damn near every living thing there is.\n\nWe want to slap labels and definitions on these things, but they are all the product of a very messy, sloppy, uncoordinated, random and disorganized process. Evolution doesn't make things neat and orderly; it results in things that work. We want things neat and orderly, and evolution, if it could talk, would tell us, \"Tough shit.\"\n\n(I'm not arguing for some metaphysical/supernatural BS here, BTW. I know it kinda sounds that way, but I'm not)",
"One thing that must be said is: The difficulty in defining what constitutes as life and what constitutes as non-life is very powerful evidence that life came from non-life."
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26ycsl | why are stories about individual rape cases in india top stories in united states news media? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/26ycsl/eli5_why_are_stories_about_individual_rape_cases/ | {
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"Remember the media outlets are businesses, so it is all about ratings, and what ever gives the best results is what they talk about. So if India is the \"ticket\" that is what gets published, shown, ect.",
"Misogyny is a massive problem in India. So thats why its important. But if you're wondering why they use individual rape cases instead of talking about the big overarching issue, its because news will always get more attention when its about individuals. People are far more likely to tune into a story a specific person's sad, emotional and personal experience than they are to tune into a story about how \"women are raped a lot in India\". By focusing on personal, individual stories, they can draw the attention of more people, and then direct that attention towards the larger issue.",
"The heinous circumstances behind the [Delhi Gang Rape](_URL_0_) case brought it all to spotlight. Then the [Swiss tourist rape](_URL_1_) gave it an international angle. The recent rape/lynch cases reaffirms the \"image of rape in India\". Now its just \"the hot ticket\" so people will read it, and media will prosper. ",
"I said this before in another thread. \n\nRape and other crime happen a lot all over the world to POOR people, especially if they're homeless (vulnerable populations). \n\nIndia has a large income disparity (gap between rich and poor). Thus, there are many stories you can choose from (many many poor). \n\n**Why do we hear about it?** \n\nA: India is going through a phase where there are a lot of social movements because people know rape is wrong, so it's highly publicized now. You only hear about it because there is local outrage. \n\n**Why are Americans so interested?** \n\nA: There are a lot of social implications with the poor people who are being raped (by other poor people) in India, which make the background of rape stories more interesting. For example: [\"Untouchables\"](_URL_0_) are basically the unwanted people in Indian society (much like gypsies in Europe), in the strata of the caste system. Ironically, it's similar to how we treated black people no more than 50 years ago.\n\nHowever, like I said before, I believe that if we close the gap between rich and poor, we'll see a lot less poor people/homeless. With less poverty = less rape/other crimes. Poor people are being raped all around the world. ",
"Media outlets just want to create uproar and anger among the people while still trying to call America awesome. If media outlets reported rape in America, people would be crying out that this country is horrible and investors/citizens/businesses will lose their confidence in America. India is a perfect country to create sensational stories about because it is on the other side of the world. People in America already have a negative stereotype about India in their minds so it is easy for the media to take advantage of this.\n\nThe reason why they choose India over other countries is because India is almost to the point where it can count as a developed country. Countries in Africa and South America have a long way to go before they can reach that point. India has just enough of a voice in international affairs for people to care about them but they still have that ancient negative stereotype in the minds of Americans that gives media outlets enough content to take advantage of.",
"Why are isolated American shootings top stories in Australian news media?",
"reddit will tell you it's because they want to bash India while ignoring their [US's] own problems.\n\nIn reality, it's because there's a different mindset to it there. You don't hear about the cases where someone got raped and the police swooped in and arrested/jailed the guy. You hear about the case where nothing was done and/or it was done by public servicemen. You hear about the cases that are so absurd and foreign to someone used to the *relatively* functional justice system in the US.",
"\n > ELI5: Why are stories about individual **gang** rape cases in India top stories in United States news media?\n\nFtfy.\n\nIts not just India. There was a story about a gang rape occuring in Malaysia the other day on the front page of Reddit.\n\n",
"ITT Indian nationalism vs American nationalism.\n\nThe thread title is a loaded question anyways. Indian rape stories are NOT top stories in the US. I have never, ever seen an Indian rape story be the lead story on a US newcast. Not even close. If anything they would just get a brief mention towards the middle or end of the broadcast and that's it.\n\nReddit likes the play the 'India and Gang rape' angle a little bit though. ",
"It's not the rape in itself that is newsworthy, it's the reaction of the authorities and the local people to the rape that outrages people in the US.",
"I would argue that this is a big story in the international media primarily because it is local Indian media that are hyping these stories up!\n\nIndian media at the moment, after the bus rape especially, now highlight pretty much every horrific rape.\n\nThis then gets carried over to the BBC, and then heads to CNN and the rest of America because these news outlets have a major audience within India as well.\\\n\nThis is the main reason why! It's not to do with American media hating on India or not wanting to report anything else about India.\n\nIf the Indian media do not highlight it as much, you will not be hearing these stories in the international media either!",
"Because they are really bad with very little consequences ",
"Individual cases speak more to Americans. We respond to personal stories rather than abstract ideas.\n\nBlacks had been mistreated in the South for a long time, but it was the story of the murder of Emmitt Till that made that abuse tangible to other Americans.\n\nSimilarly you can talk about bad working conditions, human trafficking, widespread poverty, etc. And Americans will sympathize, but it just won't be real to us. These individual stories of unpunished rape strike a chord in our individualistic hearts."
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cbqw0f | why is there more visible smoke when people vape compared with regular cigarettes? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/cbqw0f/eli5_why_is_there_more_visible_smoke_when_people/ | {
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"Vape liquid has chemicals that hold on to water very well. It's the same chemicals used in fog machines. Cigarette smoke it's just small soot particles",
"Like the first guy said, cause it's not actually smoke. Plus, I dont think you could even rip on a cigarette like you can with a mod."
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f6yyex | What was it like to be a European visiting Africa during the Victorian period? | I know that the native populations of African colonies were often treated poorly, through forced labor, assimilation, etc., but what was it like to be a European visiting (probably for business purposes)? I’m aware that there are some mansions in Kenya from this period, including one now used as a giraffe hotel, but beyond that I have had a very difficult time finding any sources. Were natives used as servants like in the American South? Was it seen as dangerous and scary, or interesting and adventurous? Did anyone ever vacation to Africa for pleasure rather than business? How common were towns built for European visitors/residents? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/f6yyex/what_was_it_like_to_be_a_european_visiting_africa/ | {
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"First, let me note that this is really a huge question. Africa is the world's second largest continent and it's incredibly diverse. And the Victorian period was really long, from 1838 to 1903. I'll try to give a partial answer focusing only on tourism and on the later Victorian period (after about 1885 or so) and on sub-Saharan Africa. North Africa and Egypt are their own particular thing.\n\nSo, there wasn't much tourism in Africa at all during this period. And what little there was, happened in just a few places. When we think of colonial white tourists in Africa, we're probably thinking of the period from around 1900 to 1940. Most of the tropes that are associated with \"old time\" African tourism -- \"great white hunters\" on safari, caravans of native bearers, a luxury hotel at Victoria Falls, biplanes -- are early 20th century, not 19th century. Before 1900 there weren't a lot of whites in Africa for any reason, and most of those were merchants, missionaries, or engaged in some colonial enterprise like mining, plantation farming, or rubber extraction. \n\n\nKeep in mind that before 1900, mass tourism barely existed, and tourism to someplace as distant as Africa was almost strictly limited to the wealthy plus a few eccentrics. Also, most of sub-Saharan Africa was really dangerous to visit well into the 1880s! That's because Europeans didn't really get a handle on tropical diseases until around then. As late as the 1870s, you had large numbers of Europeans dropping dead from various pestilences. A while back I visited the island of Goree, just off the coast of Senegal. There's a memorial there to thousands of people -- including hundreds of Europeans -- who died in the yellow fever epidemic of 1878. Would you want to visit the modern Congo in the middle of an Ebola epidemic? Or Wuhan, China right now? That's how most Europeans felt about Africa before 1880. People did go there -- but they saw it as dangerous, so they didn't go without a good reason. \n\n\nAlso, large chunks of Africa were still no-go areas because of the violence associated with colonialism. You really wouldn't have wanted to be a tourist in South Africa during the Zulu Wars. And you really REALLY wouldn't have wanted to be a tourist in the Congo during King Leopold's genocidal rule. Lots of parts of Africa were pretty peaceful during the period 1880-1900, but lots of other parts weren't. \n\n\nSo, up until around 1880 tourism in Africa was sort of like tourism in Antartica today: a few people did it, but they were mostly wealthy and mostly stuck to the coasts, plus there were a few eccentrics doing who-knows-what. \n\n\nAfter 1880 you do see a bit of tourism, mostly built around safari hunting. \"How and why did safari hunting become popular\" is its own interesting question, but let's just note that it did. But while it certainly existed in the 1890s, it didn't really take off until after 1900. \n\n\nAnother thing to keep in mind is that up to 1900, most of Africa was still really hard to get to. The automobile was unknown. Railroad construction was just getting under way. Most of the continent required a long walk inland from a coastal port, and there weren't that many good coastal ports. Telegraph lines existed, but only to selected locations, so it was easy to simply disappear. \n\n\nOkay so, to answer a few specific questions: \n\n\nWere natives used as servants? -- Of course. That was true pretty much everywhere under colonialism, but it was especially true in Africa. Why import a European, at vast expense, when you can train an African to do the job? You can pay him almost nothing! All the servants were Africans. And despite constant grumbling by the colonials about how lazy and unreliable the Africans were, they found no difficulty in running all sorts of enterprises, from railroads to luxury hotels, staffed almost entirely by African workers. \n\n\n Was it seen as dangerous and scary, or interesting and adventurous? -- Mostly dangerous and scary (though sometimes wild and interesting) up until around 1880, then gradually less scary and more exotic / cool. \n\n\nDid anyone ever vacation to Africa for pleasure rather than business? -- A few people, and mostly late in the period, and mostly to a short list of relatively safe, peaceful destinations, particularly South Africa, Senegal, and Kenya. Since Africa is huge, there are some interesting exceptions. For instance, the avant-garde French poet Arthur Rimbaud spent the 1880s bouncing around East Africa, doing everything from gun-running to amateur exploration to becoming one of the first Europeans to export real Ethiopian coffee from Ethiopia. And there were a few travel writers and amateur naturalists; those guys pop up everywhere. In the 1890s, a seemingly ordinary British woman named Mary Kingsley simply decided to go to West Africa. She ended up traveling thousands of miles deep in the bush and writing two books, one of which -- \\_Travels in West Africa\\_ -- was an instant best seller and is still worth reading today. \n\n\n How common were towns built for European visitors/residents? -- Actual towns? Quite rare. There are a few towns built by Europeans to live in, like St. Louis in Senegal. But even there, the locals outnumbered the Europeans. There were regions of European settlement, like the Boer lands in what's now South Africa, and the highlands of Kenya and Tanzania which were claimed by English and German settlers. But, again, locals outnumbered Europeans even there. Think about it. Why would a European move to live in Africa? Well, because you would have cheap abundant labor to do the farm work, dig the mines, lay the rails, shovel the coal, pave the roads, and do all your housework. That was the whole point of being a European colonist! \n\n\nLater in the 20th century you would get colonial segregation, most famously in the form of South African \\_apartheid\\_. But that was a 20th century thing. In the 19th century, most Europeans in Africa lived surrounded by Africans, and there weren't really any all-European towns or neighborhoods yet.\n\nI'm not sure if this answer is what you're looking for, but I hope it helps."
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3uz2yh | why does the united states have a disproportionately high number of the top ranked colleges/universities compared to the rest of the world? | Most college/university rankings will be nearly 80% American. How did it come about that the US developed such a strong higher education system? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3uz2yh/eli5_why_does_the_united_states_have_a/ | {
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"University ranks are highly contested since ranks are quite subjective. One obvious bias is that a lot of ranks focus on how often scientific articles get quoted (purely quantitative). Since English is a universal language, English speaking universities tend to have a clear advantage over French or Italian. This is quite documented included other biases, so I would encourage you to google it.\n\nThat said, I would expect universities from the US or England to have a certain advantage based on how the west has had a lead on science over the past centuries and they have a strong educational system with significant funds invested going back to Carnegie and Rockerfeller's support of the libraries and educational system - and of course predating that with the old British Universities that were an inspiration for the US.\n\nIf you want more of a historical view I would encourage you to post in /r/askhistorians.",
"Where do you get the 80% from? I'm guessing this number is rather bigger than most lists I've seen. \n\nSubjectivity of ranking aside, I'm not quite sure how disproportionate the American dominance is. The US has a huge population and is incredibly rich compared to the rest of the world. It makes sense that country with the most leading universities is the US. \n\n",
"At least in terms of research, the US has the advantage of fascism and WWII destroying much of the research networks of Europe. It used to be that in much of science, you pretty much had to go to grad school in Europe (and especially Germany), and lots of American scientists did that. But the combination of the physical destruction of many European universities, combined with persecution of Jews causing many prominent scientists (Einstein, Fermi, etc) to flee to America, plus after the war the US picked up scientists like von Braun who worked for the US in exchange for not being charged with war crimes (\"Operation Paperclip\"), it has been hard for European research to come back after these blows.",
"I recently saw an interview with Michio Kaku where he talked about America having the best universities yet a terrible education system, and how the majority of students at the best universities are not American born anymore. Perhaps these institutions use their existing long term standing and notoriety to attract the best students from around the world and the students in turn keep the institutions alive. ",
"Although I've never seen a ranking 80% comprised of US unis (usually it's 50% tops), there are a number of factors that are likely to contribute to this:\n\n* Papers published in English get read far more than those in other languages, and paper citations are a huge factor in most ranking agencies. Already, therefore, English-speaking countries are at an advantage\n\n* Of the English-speaking countries, the nations that have been the most powerful, wealthy and influential for the longest time are the UK and US.\n\n* The US population is 5 times larger than the UK's, meaning that all else being equal, the US should have multiple times the number of top-ranked unis than the UK\n\n* Revenue - most countries fund their unis publicly and cap student fees (if there are even fees at all). US unis, especially prvate ones, can charge whatever they want, which gives them a massive stream of revenue that isn't available to UK, Canadian, Australian, European unis. This however has significant drawbacks for students who end up with ridiculous debts.",
"This occurs for several reasons already mentioned. One that is relevant in German speaking coutries is that the universities here often focus on few subjects rather than the plethora of subjects that Harvard or Stanford might focus on. For example, the Max-Plank Institute (_URL_0_), has seen more Nobel Laureates come through its doors than Harvard and has arguably done more for many aspects of sicence in the last few years. Yet, because it only focuses on a few areas of reasearch, it does not show up in rankings. The London School of Economics is another example of this. It is 71st on world rankings, but ranks head to head with Harvard considering Social Sciences only. \n\nAnother aspect is the language of instruction, as many universities outside of the US and England will teach in their native tounge and publish in that tounge as well. \n\nMoney was mentioned, but is not the issue in the way your might expect. European universities may have a lot of money to spend, but will not put as much of it into adverstising and marketing. It is due to thsi that they are not as prominent and do not attract as much attention from others. \n\n",
"Size is also a factor. A US university can have tens of thousands of students and researchers. In France, the ENS Ulm has done an incredible job in quantum physics and in mathematics with promotions of roughly 40 new undergraduates per year in each subject. They basically try to attract prodigies, offer them a 1300 euros monthly stipend, and have older students serve as tutors. It is one of the reason why France has the second biggest number of Fields medal (after the US, but with 20% of the population size)...\nThe result is that France is trying to merge many small elite universities and engineer schools into a much higher ranked entity.",
"Okay wow I can't believe that no one has mentioned this... But elite institutions are all private run, unlike most rest of the world that has state funding for all of it's schools, it makes it more competitive, and the alumni donation thing makes investment capabilities soar. T",
"After studying in the USA as well as in universities in South Korea, South Africa, and Australia (all within the top 100), I feel that this question has no easy answer. Part of it, I feel, is cultural.\n\nIn the USA and South Korea, academia is taken very seriously. It is hard to get into a position to research, let alone publish in a competitive journal. This competitive culture drives up their outcomes. US schools also get an incredible amount of interaction, networks, and funding from alumni (often through sports), which gives them an advantage. \n\nSouth Korean education is stupidly competitive, despite being a considerably smaller country. Similar to the USA, they have a strong \"old boy' alumni culture for funding and networking.\n\nSouth Africa is dealing with other issues that affect the rankings.\n\nAustralia lacks in some regards when compared to the US or ROK. Despite being a postgraduate student, I felt a complete lack of competition in research and academic rigour. It is comparatively easy to get into a research position -- with a poor research question -- when compared to the US and ROK. Most of the PhDs in Australia would probably rank as 1st year MA students in the USA/ROK. In my MA program, most of the Australia students barely showed up. Postgraduate studies are basically seen as a gap year. International students are basically cash cows.\n\nAdditionally, most Australian universities suffer from a lack of funding and interaction from alumni. The funding comes from international students and the government. Australian schools' rankings benefit greatly from factors like employability, inclusivity, and internationalisation (just hope you are Aussie when job searching...). These compensate for the lower quality of research and academic rigour.\n\nThese elements all feed into the ranking criteria. For example, ANU (#17) ranks so highly internationally because they get 'special funding' from the government and, being in tiny tiny Canberra, benefit from a more engaged alumni network. They also produce high quality research. Then there is a huge gap -- USyd, UMelb, and UQ rank closer to 50.",
"University rankings are rubbish, there is a clear example of this. Edinburgh university is consistently third or fourth in the world rankings for British universities, but 10th or so generally when ranked only against British universities. Clear contradiction. ",
"Endowments. \n\n1) Universities with huge endowments can (this is the perception anyway) do more research, and more interesting research.\n\n2) Interesting and plentiful research draws the best researchers.\n\n3) The best researchers do prominent research.\n\n4) Prominent research and reseachers increase the prestige of a University.\n\n5) Undergraduate students go to prestigious universities to be milked like dairy cows, both as students and later on as alumni which:\n\n6) loops back into point 1) by increasing the size of a University's endowment. \n\nI had to do some consulting work on this topic, so perspective may vary."
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7dxpuf | Does the expansion of the universe mean that the planets are moving away from each other? | I know the galaxies are moving apart from each other due to cosmic expansion, but does the same effect happen to the Earth and other planets in the solar system on a lesser scale? | askscience | https://www.reddit.com/r/askscience/comments/7dxpuf/does_the_expansion_of_the_universe_mean_that_the/ | {
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" > I know the galaxies are moving apart from each other due to cosmic expansion, but does the same effect happen to the Earth and other planets in the solar system on a lesser scale?\n\nNo. On the scale of the solar system, the expansion of space is so small as to be negligible. And even that negligible influence is easily overwhelmed by the strength of gravity, which pulls planets back to where they \"should\" be.",
"No, the planets are not moving apart. The expansion of the Universe is derived from general relativity wherein an expanding Universe is a solution to Einstein's field equations for a uniform Universe (described by the Friedmann equations). \n\nOn small scales, the Universe is not uniform and so uniform expansion is not a good approximate solution to the Einstein's field equations in that regime. \n\nAs for the Big Rip (mentioned elsewhere in the comments), yes, it is possible that whole galaxies, planetary systems or even planets themselves are ripped apart due to expansion. This occurs when the global expansion rate becomes sufficiently high that no bound structures (like galaxies, planetary systems or stars and planets themselves) can form or persist. \n\nThat's a pretty crazy and cool scenario to say the least! However, for it to be plausible it should be generated by a plausible mechanism. Most *dynamic* dark energy models (as opposed to boring cosmological constants) are realized by imagining a (scalar) field permeating the Universe, with similar properties to the Higgs field or the imagined inflaton field driving inflation in the early Universe.\n\nSuch models are known as \"quintessence\" models and have been formulated since the 80's (even before the discovery of dark energy itself) by cosmologists like Peebles. These models of dark energy are plausible in that such scalar fields come directly from quantum field theory. However, they cannot lead to a Big Rip. Instead, the most natural such models have the quintessence field behaving like 'normal' dark energy (no Big Rip) and then, after some finite time, transitioning to behaving like ordinary matter and ceasing driving an accelerated expansion. Other models have accelerated expansion continuing forever but at an ever slower pace. \n\nEach of these lead to no Big Rip. To get a Big Rip from some new field, you need to imagine something crazy and maybe a bit too unrealistic like a scalar field with negative kinetic energy. Otherwise, it turns out, you don't get an expansion that speeds up and speeds up until it reaches an infinite expansion rate at some finite time in the future (the Big Rip)."
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1j5ica | what does 42 mean? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1j5ica/eli5_what_does_42_mean/ | {
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"Nothing on it's own.\n\nIt's a reference to a book called the hitchiker's guide to the galaxy. One of the worlds most famous science fiction novels.\n\nIn the book is a story about a computer that calculates the awnser to \"The ultimate question about life, the universe and everything.\" It does so, eventually after millions of years coming up with the awnser '42'.\n\nOf course the philosophers don't understand the awnser. But that's because they don't know the actual question.",
"There is a very popular media franchise (plays, then books, then movies and TV shows) called *The Hitch Hiker's Guide to the Galaxy*. It's a comedy sci-fi story in which a human refugee from Earth explores the galaxy and gets involved in all kinds of silly situations.\n\nIn its most famous part, the universe's most advanced race builds the universe's most advanced computer, and sets it to the task of answering 'the ultimate question of life, the universe, and everything.' They believe that it will explain the function and meaning of all existence and bring everyone to enlightenment. It calculates at full load for over seven million years, and eventually gives the answer \"42.\" Everyone is confused, and then realises that now they have to figure out what 'the ultimate question' actually is, and how it could possibly generate the answer 42. It is said that if anyone actually figures out what the universe means, it will be instantly replaced by a new universe that makes even less sense. It is also said that this has probably already happened.\n\nBecause this is the most famous portion of a book very popular with geeky folks, it's referenced and parodied a lot online.",
"I can only assume you talk about 42 as a reference to \"the hitchhikers' guide to the galaxy\". In this novel, a computer was built to answer the ultimate question to life, the universe and everything. A few million years later, the computer was finished calculating that answer and it was 42. Nobody ever learned what the question actually was that this answer answers.",
"Its the answer to life, the universe, and everything. We just dont know the answer yet."
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4cewez | what prevents the caramel filling in chocolates from hardening? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4cewez/eli5_what_prevents_the_caramel_filling_in/ | {
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"I am actually working in a freaking chocolate factory as a process engineer and the best answer I can give you is: Well, It doesn't harden at that temperature.\n\nIt's just different sorts of caramel.\n\nThere is solid caramel candy and there is this liquid/gooey caramel. Has to do with sugar/water rates, the types of sugar you use, cream or milk beeing added etc.\n\nSo it's a little like asking why water is liquid and jello is not. It's just what makes up the structure or rather, what prevents the structure to form."
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4lu0ey | intel is comming with a 10core processor. what is a core? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4lu0ey/eli5intel_is_comming_with_a_10core_processor_what/ | {
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"A CPU is made up of many parts (other parts include the L3, L2, and L1 caches, the memory controller, there are actually quite a bit of parts on the CPU), but probably the most important parts are the cores. The cores are the computational engines of the CPU, they are what do the calculations. Each core can do one calculation per clock cycle, the complexity of this calculation however depends on something called the architecture, which is just the design of the core, how all of the transistors that make it up are laid out. A clock cycle is how long it takes to load this information, execute it, and reset everything. CPU clocks are expressed in units called Hertz, which means per second. Modern CPUs have clock speeds of around 3 Gigahertz, or 3 billion Hertz, so each core can do the computations 3 billion times per second.\n\nMore cores on the CPU will help in some tasks, not all however, such as those that require knowledge of prior computations. Take the expression (3 + 4) * 7 for example, you should probably add 3 and 4 together before you multiply by 7, this is a multi step equation that requires you to know prior computations. Other tasks can use a lot of cores, for example video rendering uses a lot of cores since if a core finishes with one frame, it can move on to the next frame.\n\nThis is nothing new however, Intel released a 22 core CPU a few weeks ago and has a 90 core CPU as well in experimental labs. More cores does not necessarily mean better however.",
"Let's say the cpu is some kind of calculator, for simplicity sake. You put some numbers into the calculator, then you ask the calculator to do something with it (subtract, add etc). Then the calculator gives you a number back, the result.\n\nWhy more cores? Let's say you have 2 math problems. 1 core would mean 1 calculator. So the calculator needs to do a calculation and give a result, then do the next problem and give that result. With 2 cores you would have 2 calculators, 1 calculator does the first problem and the second one does the 2nd problem, they both give you a result at the same time.\n\nMore cores = more calculators.\nThe speed of the calculations = clock speed.\n\nWith more cores you would do more calculations at the same time, with more clock speed the calculators work faster. Some programs are programmed to use 1 calculator (old games), some programs can use 4 to 8 calculators to do math with (photoshop)."
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2o6d43 | why some states aren't eligible for participation in sweepstakes, promotions, etc.. | An example is Amazon Smile, while people from states can enter and participate, they are limited to what kind of activities that can take place, solely for residing in a state.
i.e.
3. Advertising AmazonSmile
You may promote or link to the AmazonSmile Site only so long as you comply with the following requirements:
You may only do so on your site and may only use such of our or our affiliates' trademarks or logos ("Amazon Marks"), links to the AmazonSmile Site ("Links"), or other content we may make available to you (collectively, "Content"), in all cases in accordance with Program Participation Requirements and the Program Trademark Guidelines;
You may not do so in a way that is misleading or confusing to customers or that does not accurately represent the AmazonSmile Site or the Program (e.g., by expressing or implying that we sponsor or endorse you or any other cause or that we support your position on any issue);
You may not engage in any promotional, marketing, or other advertising activities on behalf of us or our affiliates, or in connection with the AmazonSmile Site or the Program, in any offline manner, such as in any printed material, mailing, or other document, or any oral solicitation; and
Charitable organizations headquartered in one of the states listed below may not send emails that exclusively advertise AmazonSmile, although these organizations may include information about AmazonSmile in emails, such as email newsletters, that also contain other content unrelated to AmazonSmile. These states are: AL, AR, CO, DC, FL, HI, ID, IL, IA, LA, ME, MD, MI, MN, MS, MO, NE, NM, OH, OK, RI, SC, SD, UT, VT, and WY. Organizations headquartered in any other state may promote AmazonSmile to their supporters using email advertising dedicated to the promotion of AmazonSmile, or emails that contain AmazonSmile information along with other unrelated content. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2o6d43/eli5why_some_states_arent_eligible_for/ | {
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"Some states have passed specific laws banning these types of promotions.\n\nThere was a time when there were a lot of scammy, fraudulent \"sweepstakes\" that harmed a lot of people. The states took action to restrict the ability of companies or individuals to run those kinds of promotions.\n\nSince Amazon is so big, it would face meaningful sanctions in those states if it ignored those laws."
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f7sfel | how does "auto generated subtitles" translate audio into text? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/f7sfel/eli5_how_does_auto_generated_subtitles_translate/ | {
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"Basically you take the software that turns speech into text - \"Okay Google, how is what I'm saying to you right now showing up on my phone's screen?\" - and point it at a youtube video's audio track. Take all the text it produces and make it into a subtitle feed.\n\nObviously it's not perfect, but it's better than nothing.",
"It works almost exactly the same as digital assistants such as Siri, Alexa and Google Assistant do when they listen to your voice commands. Which is called \"Automatic Speech Recognition\" or ASR for short.\n\nFirst you need to teach a computer program to be able to recognize speech and match that to words. This is done by giving a machine learning program lots of examples to start with.\n\nLike *\" hello program* *here are hundreds if not thousands of hours of already correctly subtitled videos. Try to recreate it. \"*\n\nThe program then works really hard until it is able to recreate the subtitles at which point you start to give it new videos without any subtitles to compare with.\n\nThe program can now detect speech automatically but it is not perfect. It still makes a lot of mistakes. But the beauty of it is that it can learn from mistakes. All it need is feedback just like we do and hopefully get in school. If it hears \"Hello\" and thinks it's \"jello\" all you need to do is correct it and it will remember and expand from it.\n\nSo now when you go to YouTube and turn on auto generated subtitles the video is either feed into this program on demand or has already been processed and the result is speech to text which is synced. Example of output from the program would be: At 2 minutes 34 seconds the word \"**Malarkey**\" is uttered.\n\n & #x200B;\n\nnote: it is obviously more complex as machine learning is involved which is a whole other subject and is more complicated then i made it seem but the gist of it holds true.\n\n*Edit: Spelling.*"
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5wps9t | How Much Did Weakness in Eastern European States contribute to the Outbreak of WWI? | Long time lurker here - asking my first question on this amazing sub.
So I've read the FAQ relating to the causes of WWI. The FAQ certainly explains how Kaiser Wilhelm II grossly mismanaged the diplomatic situation, allowing the Entente Cordiale between the UK and France and the Franco-Russian Entente to form. It also explains the ethno-nationalistic tensions in the Balkans well.
To what degree is my line of thought below actually substantiated in the historical record, and what sources do we have supporting or undermining it?
It seems to me that severe political and social problems in the Austro-Hungarian, Ottoman, and Russian Empires contributed heavily to the outbreak of war. If I recall my reading and documentary watching correctly, the Austrians were terrified of looking weak to Serbia (because they were weak, with secessionist movements in all non-Austrian/German regions); thus they were spoiling for a fight to reassert military supremacy over their backyard.
The Russians seem to have been equally terrified of such appearances, given that they made clear their intent to defend Serbia with their "period preparatory to war." I imagine that after having faced famine, a lost war to Japan, and a revolution in the last ten years, the Tsar needed to cover up his failures with a glorious rescue of a fellow Slavic people.
Serbia was a tiny country with limited resources and it seems that a war by a great power with another great power over the fate of Serbia could only be justified by a deep-set fear of one's inner weakness being revealed.
As for the Ottomans, the whole Balkan tinderbox situation would not have occurred if they were not so weak as to be totally unable to defend their Balkan territories against ethnic rebels and their European sponsors. It seems that diplomatic chaos in the Balkans, and a corresponding war over the pieces of the Sick Man of Europe, was inevitable from the very moment the Ottoman hold on the region was first successfully challenged in the Greek Rebellion in the 1820s and 30s. | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/5wps9t/how_much_did_weakness_in_eastern_european_states/ | {
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" > As for the Ottomans, the whole Balkan tinderbox situation would not have occurred if they were not so weak as to be totally unable to defend their Balkan territories against ethnic rebels and their European sponsors. It seems that diplomatic chaos in the Balkans, and a corresponding war over the pieces of the Sick Man of Europe, was inevitable from the very moment the Ottoman hold on the region was first successfully challenged in the Greek Rebellion in the 1820s and 30s.\n\nI can speak to this part but not to the others. There's a few things to deal with here, but in regards to WWI it's that while the origins of the conflict lay in the Balkans, there is nothing inherent in an unstable Balkan region that was going to lead to a general European war. Indeed, one of the reasons why the July Crisis seemed to unravel in almost slow motion and why the news of the assassination of Franz Ferdinand seemed to be so trivial was that in the 1910s there had already been two Balkan wars and several Balkan crises.\n\nThat general European war could not have happened without the wider alliance structures and in particular what Christopher Clark calls the \"Balkan Inception Scenario\", that is, the acceptance on the part of Russia and France to go to war over a conflict between Austria and Serbia that would almost certainly trigger the Austro-German alliance.\n\n > if they were not so weak as to be totally unable to defend their Balkan territories against ethnic rebels and their European sponsors....from the very moment the Ottoman hold on the region was first successfully challenged in the Greek Rebellion in the 1820s and 30s.\n\nI mean, that's quite a tall order. The \"European sponsors\" in the Greek War of Independence consisted of Russia, Britain and France against the Ottomans alone. In other words, the two greatest land powers and the greatest sea power in the world at the time. The Ottoman's ability to prevent Greek independence probably sank with the Egyptian fleet at [Navarino](_URL_0_) as the Egyptians under Muhammad Ali were almost certainly the most competent forces within the empire at the time.\n\nIn any event that's a bit of a sidebar to the more relevant aspect of your question:\n\n > It seems that diplomatic chaos in the Balkans, and a corresponding war over the pieces of the Sick Man of Europe, was inevitable from the very moment the Ottoman hold on the region was first successfully challenged\n\nI mean, sure, in the sense that without independent Balkan states that WWI couldn't have broken out in the way that it did and that the post-independence Balkans was going to be a mess ([as indeed it was long after WWI ended](_URL_2_)).\n\nBut I think that's missing two issues:\n\nFirstly, Ottoman involvement in the war at all was entirely contingent, and perhaps more than any of the Great Powers who went to war in 1914 it was a war of choice, and in particular the choice of the pro-German Enver Pasha. Of note is that the Ottomans were the last of the major 1914 belligerents to actually go to war, not doing so until the Turkish-flagged but German-manned *Goeben* and *Breslau* (newly inducted in the Turkish navy with Turkish names, *Yavuz Sultan Selim* and *Midili*) attacked the Russian Black Sea fleet and ports on 29 October. There was very little preventing them from maintaining neutrality (and they were even offered inducements to do so) or of joining the Entente (which they pursued, though it's not clear to what extent this might have just been a smokescreen for the imminent German alliance or whether they were, genuinely, looking to join whichever side would offer the best deal.)\n\nSecondly is the issue of why \"The Eastern Question\" hadn't already led to a general European war. \"The Eastern Question\" effective refers to the question of \"After the Ottomans, then what?\" It having been assumed since the mid-19th century that the Ottoman's days were numbered.\n\nThe primary answer is that while all of the European powers thought the Ottomans were going to fall sooner rather than later, and everyone wanted a piece of the imperial pie, none of the respective sides could decide what to do about it and indeed were willing to go to war to protect the integrity of the Ottoman empire, which was notably demonstrated in the Crimean War in which Britain and France backed the Ottomans against Russia despite having sided against the Ottomans in the Greek wars mentioned earlier. The outbreak of WWI with the particular alliance structures that it had resolved the question: the empire was to be divided entirely between Britain, France and Russia (the Sykes-Picot-Sazonov agreement). But that was not a foregone conclusion until war actually broke out and until the Ottomans joined the Central Powers.\n\n > the Sick Man of Europe\n\nThere has also been quite a lot of pushback against this notion of a \"Sick Man of Europe\" in the past several decades of scholarship. The Ottoman Empire of the Young Turks seemed to have been in a process of revitalization, modernization and mechanization. While it was certainly not a state comparable to, say, Germany or Great Britain, there are no indications that the Ottoman Empire was on the verge of collapse before the war broke out, the Ottoman military consistently out-performed the expectations of the opposing sides (perhaps most notably at Gallipoli and Kut, though also fighting the British to a multi-year standstill at [Gaza](_URL_1_).) They also more or less continued fighting right through to the end of the Turkish war of independence in ~~1924~~ 1923 [edit: war ended in 23, Republic of Turkey declared in 24, doh!] and came out of the entire ordeal under the strong leadership of Ataturk.\n\nIn any event, a bit of a side question, but as a kind of **TL;DR** I'm not entirely sure how one could blame the Ottomans for this one, even though they were certainly a part of the overall balance of power and political situation in which the war was possible and then broke out.\n\nSource wise:\n\nI would have a read of Christopher Clark's *The Sleepwalkers* on the outbreak of the war. For the late Ottoman Empire and their involvement in WWI, Eugene Rogan's *The Fall of the Ottomans* is quite good. IIRC the relevant chapters in Malcolm Yapp's *The Making of the Modern Near East 1792-1923* are also quite good in knocking down the \"sick man\" thesis."
]
} | [] | [] | [
[
"https://en.wikipedia.org/wiki/Battle_of_Navarino",
"https://en.wikipedia.org/wiki/Third_Battle_of_Gaza",
"https://en.wikipedia.org/wiki/Srebrenica_massacre"
]
] |
|
jdyhd | difference between beer, whiskey, liquor, rum, etc. | And is it true that whiskey causes more fights? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/jdyhd/eli5_difference_between_beer_whiskey_liquor_rum/ | {
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"text": [
"The quick answer: how they're made and what they're made of.\n\nBeer:\n\nBeer is made from water, hops (a kind of flower), barley, yeast and other ingredients. The barley and any other \"mash\" ingredients are cooked together. Yeast consumes sugar taken from the barley and turns it into alcohol and carbon dioxide. The carbon dioxide makes it fizzy. Hops is added to add flavour.\n\nWhiskey (whisky, scotch, bourbon):\n\nWhiskey is made from water, barley, yeast and other ingredients. The barley and other grains are put in water, then allowed to dry, and then cooked over a kiln that burns a flammable moss called peat. The barley is then cooked in water with yeast added. Yeast process the sugars and turn them into alcohols, and the liquid is distilled until it is very strong (it has a high percentage of alcohol). After this, the contents are put into wooden barrels, and the alcohols and water in the mixture draw out chemicals in the wood which add different sorts of flavours to the end result.\n\nRum:\n\nRum is not as specific. Rums are made by taking molasses or sugar cane juice, fermenting them with yeast, distilling them, and aging and/or adding spices. There are several ways to make rum, which can result in fairly pure \"white\" rum to spiced rum which is darker and has interesting herb flavours, and aged rums, which are aged in wooden barrels and which (like scotch) draw out chemicals out of the wood, bringing in new flavours and darkening the liquid.\n\nLiquor and Spirits:\n\nLiquor is a general term for a wide variety of beverages which are made in a wide variety of ways.\n\nSpirits is another general term which includes beverages which are primarily distilled, such as scotch, whiskey, rum, and vodka.\n\nLiquor, depending on how the word is used, may include anything that has alcohol which isn't beer or beer-like. If it is spelled \"liqueur\", it is often flavoured with fruits, flowers, or herbs and is sweeter than \"spirits\".\n\nAlcohol and fighting:\n\nWhether people get in fights while they're drunk depends on the person, not what they're drinking. Alcohol affects different people in different ways, and sometimes it even depends on how much they drink. Some people might get more talkative and jokey, some people might get more giggly, some people get very tired, some people get depressed, and some people get annoying and angry.\n\nWhile the type of drink doesn't affect one's behaviour, it is true that certain drinks have an \"image\". If someone is an angry, mean drunk and is proud of it, he may prefer to drink an alcoholic beverage which has a \"working class\" and masculine image, such as mass produced beer, or an inexpensive whiskey or tequila. They would be just as annoying if they were drinking more \"sophisticated\" or \"feminine\" drinks such as a high quality scotch, \"craft\" beers, liqueurs that are pink or light blue, Amaretto and 7-Up, or wine coolers, but that would not project the \"manly\" and \"hard\" image they want to associate themselves with.\n\nMy *personal* experience is that you're a jerk when you're sober, you're a jerk when you're drunk.",
"The quick answer: how they're made and what they're made of.\n\nBeer:\n\nBeer is made from water, hops (a kind of flower), barley, yeast and other ingredients. The barley and any other \"mash\" ingredients are cooked together. Yeast consumes sugar taken from the barley and turns it into alcohol and carbon dioxide. The carbon dioxide makes it fizzy. Hops is added to add flavour.\n\nWhiskey (whisky, scotch, bourbon):\n\nWhiskey is made from water, barley, yeast and other ingredients. The barley and other grains are put in water, then allowed to dry, and then cooked over a kiln that burns a flammable moss called peat. The barley is then cooked in water with yeast added. Yeast process the sugars and turn them into alcohols, and the liquid is distilled until it is very strong (it has a high percentage of alcohol). After this, the contents are put into wooden barrels, and the alcohols and water in the mixture draw out chemicals in the wood which add different sorts of flavours to the end result.\n\nRum:\n\nRum is not as specific. Rums are made by taking molasses or sugar cane juice, fermenting them with yeast, distilling them, and aging and/or adding spices. There are several ways to make rum, which can result in fairly pure \"white\" rum to spiced rum which is darker and has interesting herb flavours, and aged rums, which are aged in wooden barrels and which (like scotch) draw out chemicals out of the wood, bringing in new flavours and darkening the liquid.\n\nLiquor and Spirits:\n\nLiquor is a general term for a wide variety of beverages which are made in a wide variety of ways.\n\nSpirits is another general term which includes beverages which are primarily distilled, such as scotch, whiskey, rum, and vodka.\n\nLiquor, depending on how the word is used, may include anything that has alcohol which isn't beer or beer-like. If it is spelled \"liqueur\", it is often flavoured with fruits, flowers, or herbs and is sweeter than \"spirits\".\n\nAlcohol and fighting:\n\nWhether people get in fights while they're drunk depends on the person, not what they're drinking. Alcohol affects different people in different ways, and sometimes it even depends on how much they drink. Some people might get more talkative and jokey, some people might get more giggly, some people get very tired, some people get depressed, and some people get annoying and angry.\n\nWhile the type of drink doesn't affect one's behaviour, it is true that certain drinks have an \"image\". If someone is an angry, mean drunk and is proud of it, he may prefer to drink an alcoholic beverage which has a \"working class\" and masculine image, such as mass produced beer, or an inexpensive whiskey or tequila. They would be just as annoying if they were drinking more \"sophisticated\" or \"feminine\" drinks such as a high quality scotch, \"craft\" beers, liqueurs that are pink or light blue, Amaretto and 7-Up, or wine coolers, but that would not project the \"manly\" and \"hard\" image they want to associate themselves with.\n\nMy *personal* experience is that you're a jerk when you're sober, you're a jerk when you're drunk."
]
} | [] | [] | [
[],
[]
] |
|
cuppj0 | if an object traveling at 50mph impacts another object at 50mph does the combined force equal a 100mph impact or is it still the same force of a 50mph impact? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/cuppj0/eli5_if_an_object_traveling_at_50mph_impacts/ | {
"a_id": [
"exwz5pm"
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"text": [
"Each object feels 50mph \n\n\nEach one will feel it as if it hit a stationary object going 50mph. \n\n\nMythbusters did a good segment on this with 2 cars hitting each other vs a car hitting a wall. \n\n\nIm assuming both objects are essentially equal in size, a baseball hitting a bowling ball wouldn't be the same"
]
} | [] | [] | [
[]
] |
||
bhv7jl | what happens to the wind chill factor in the spring, summer and fall? | We still have wind but it's not talked about on the weather report in the non-winter months. Doesn't the wind still take things down a degree or two here and there? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bhv7jl/eli5_what_happens_to_the_wind_chill_factor_in_the/ | {
"a_id": [
"elw2t6i",
"elw3npg"
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"score": [
2,
2
],
"text": [
"All that wind does is move air around. It does make us perceive the air temp to be colder though as long as the air temp is below our body temp. Our body releases energy, making us feel colder, to try and make the air around us the same temperature. The wind then blows that air away. The faster the wind, the quicker it removes that warm air. \n\nIt doesn’t matter too much in the non-winter months because people are not worried about the cold as much.",
"It still matters; but people don't care about it as much. If it's 90 degrees F, and there's a stiff breeze, it would be weird to say \"the wind chill is 75\". Instead, people say, \"it feels nice with the breeze\"."
]
} | [] | [] | [
[],
[]
] |
|
61va36 | why are people tried for hate crimes and not just the original crime like murder? | I understand what a hate crime is and I find it deplorable to target someone for their race, sexual identity, etc. Are there stricter punishments for a hate crime murder as opposed to a regular murder? I feel like most crimes are inherently hateful so I'm hoping someone can clarify. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/61va36/eli5_why_are_people_tried_for_hate_crimes_and_not/ | {
"a_id": [
"dfhjpwe",
"dfhjw91",
"dfhnpap"
],
"score": [
6,
5,
4
],
"text": [
"Hate Crime indictments add to the penalty imposed for the original crime. You are tried for murder, but a murder which is also a hate crime will get you a larger sentence.",
"It's the difference between Dylan Roof shooting up any church at random vs specifically targeting a historical and prominent black church with direct intention to hurt and kill black parishioners/people and with the seeming attempt to incite additional racial violence. \n\nAll crimes are hateful, but the large majority are \"blind\" crimes that intend to generally hurt, vandalize and otherwise cause loss and suffering; but, not hurt someone solely as retaliation for being a specific color, gender, religion, sexual identity, etc. \n\nAnd typically, hate crimes are seen more like domestic terrorism and generally do come with stricter sentences because the crimes tend to involve a deeper level of intention behind them.",
"The federal hate crime law does not add to the penalty for a crime. It merely makes federal resources available for the investigation of a hate crime. This is to empower local prosecutors who might have trouble getting their colleagues in local law enforcement to do their job if the community at large shares the prejudices that led to the victim's demise."
]
} | [] | [] | [
[],
[],
[]
] |
|
3csjhz | Why do we get that cold tingly feeling under our skin sometimes after using things like muscle creams or patches? | askscience | http://www.reddit.com/r/askscience/comments/3csjhz/why_do_we_get_that_cold_tingly_feeling_under_our/ | {
"a_id": [
"csyq167"
],
"score": [
8
],
"text": [
"Many of these creams contain menthol (or sometimes peppermint oil, which is what menthol can be extracted from). Menthol stimulates TRPM8 receptors in the skin. These receptors are primarily for sensing cold, but menthol triggers their response and you get a cold feeling when you apply creams. Other menthol analogs could illicit a similar response through the same mechanism.\n\nSource:\n\nDavid D. McKemy. (2007) Chapter 13 TRPM8: The Cold and Menthol Receptor *in* TRP Ion Channel Function in Sensory Transduction and Cellular Signaling Cascades. \n\n\n_URL_0_\n"
]
} | [] | [] | [
[
"http://www.ncbi.nlm.nih.gov/books/NBK5238/"
]
] |
||
2m5xeg | What happens when water condenses on a hydrophobically coated object? | E.g. Spray a bottle of beer with neverwet, stick it in the fridge for a while then take it out in a high humidity climate.
Does the water precipitate on the bottom and slide off quickly?
Edit: It might behoove me to ask if the shape of the object matters e.g. a glass sphere vs something irregular like a small metal statue. | askscience | http://www.reddit.com/r/askscience/comments/2m5xeg/what_happens_when_water_condenses_on_a/ | {
"a_id": [
"cm19xeg"
],
"score": [
6
],
"text": [
"Hydrophoby is related to wetting angle, it is not pushing water away like magnet pushing metal. If the object is very hydrophobic, water forms more round droplets rather than splashes, and so it would form droplets and very likely fall/roll off the surface. This is how some plants leaves, such as aloe, are cleaned. \nYou can find more abt it here:\n_URL_0_"
]
} | [] | [] | [
[
"https://en.wikipedia.org/wiki/Superhydrophobe"
]
] |
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