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bsjo4o | Why doesn't an atoms atomic number correlate with how common the element is? | Hydrogen has the atomic number 1, and it's also the most common element in the universe. Helium has the atomic number 2 and is the second most common element.
& #x200B;
However, after that, the atomic number doesn't correlate to the elements abundance. The next most abundant is Oxygen, which has an atomic number of 8, then Carbon with an atomic number of 6.
This seems really weird to me because from my understanding, when fusion happens, for oxygen to be created, it has to first become lithium, beryllium.... etc, until oxygen. I'm guessing this is where I'm making my mistake and my understanding of fusion is not correct. | askscience | https://www.reddit.com/r/askscience/comments/bsjo4o/why_doesnt_an_atoms_atomic_number_correlate_with/ | {
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"Exactly, the fusion processes are not that straight up as \"just keep adding protons\" (the atomic number is the number of protons in the nucleus, that's what defines the element). Lithium, for example, is \"destroyed\" easily, it becomes two Helium atoms when a proton hits a Lithium-7 atom, a process called \"Lithium burning\". Check out the list of key reactions in [_URL_0_](_URL_1_), it'll help you understand how fusion works.",
"Hydrogen has 1 proton and (nearly always) 0 neutrons. Helium has 2 protons and 2 neutrons. What happens if you try to fuse these?\n\nYou can make lithium-5 by combining hydrogen and helium. That decays back to hydrogen and helium immediately. You can make beryllium-8 by combining helium and helium. That has an extremely short lifetime until it decays back to two helium nuclei. So how can heavier elements exist at all? This was an interesting question for a while. Stars cannot produce heavier elements for most of their lifetime. Once they run out of hydrogen they collapse and the interior gets really hot and compressed. The helium+helium- > beryllium-8 reaction gets more common. And once in a while a third helium nucleus hits the beryllium-8 fast enough to form carbon-12, which is stable again. This is called triple-alpha process because it needs three helium nuclei (alpha particles) to come together nearly at the same time. It only happens under immense pressure and temperatures. From there on more helium nuclei can be added: carbon-12 + helium-4 - > oxygen-16, add another one to get neon-20 and so on.\n\nLithium, beryllium and boron are rare because there is no common fusion reaction to produce them. They are produced in some exotic side-reactions or from high energy particles splitting up larger nuclei.\n\n= > Hydrogen is the most common, then helium because it can be produced in helium fusion. After that you get the products of the triple-alpha process: carbon, oxygen, neon, ... all the even-numbered low elements until iron. Not in strictly decreasing amounts because some of the reactions happen faster than others. The odd-numbered elements are again some other side-reactions. Elements heavier than iron are produced in supernovae, neutron star collisions and stuff like that, they are generally rare."
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i9cjh | How does light pass through a transparent object, slow down, then speed up again? | I know that light is both a particle and a wave, and that the refractive index of a material is pretty much a function of its density. How then, does light interact with these particles (slowing them down) and keep a coherent beam/image? | askscience | http://www.reddit.com/r/askscience/comments/i9cjh/how_does_light_pass_through_a_transparent_object/ | {
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"Because math. If you're going to model transmission through transparent media with particle-particle interactions, you have to do a bunch of complicated quantum mechanics; there is no simple, understandable explanation.",
"To address part of your question. Light doesn't slow down ever. The photons are absorbed and then retransmitted a moment later that gives the illusion of slowing down. While a photon is on the move it's traveling at c always. "
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bh9dmh | Did the fact that Stalin and Beria were Georgian have any impact on Georgia during the Soviet Union's existence? | [deleted] | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/bh9dmh/did_the_fact_that_stalin_and_beria_were_georgian/ | {
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"In short, a little bit during the era of Stalin and Beria, and mostly because of Beria.\n\nFirst, I'll make the minor distinction that Beria was ethnically Mingrelian, a group closely related to the Georgians but with their own language, who are from the northwest of Georgia (though few outside of Georgia make that distinction, and the Mingrelian language is considered by some to simply be a Georgian dialect. However the difference is more readily made within Georgia). This doesn't make a huge difference, but it is notable as it arguably played a role in what Beria did (see below).\n\nStalin may have been an ethnic Georgian (rumours that his father had Ossetian heritage have no basis in fact; the truth is no one is quite certain where the Jughashvili name comes from), but he was committed to the Communist idea of internationalism and downplayed the fact he was Georgian, more readily assuming a Soviet identity. Lenin famously accused him of \"Great Russian Chauvinism\" prior to his death, which is ironic as it meant that Stalin favoured polices that benefited Russia specifically rather than the Soviet peoples as a whole, despite not being Russian. He did not really do anything that overtly benefited Georgia during his time in office, and would only visit during the summers for vacation, and at that he would only stay at his dacha in Abkhazia (an autonomous republic in northwest Georgia, known for its tropical climate and beaches).\n\nBeria however was much more a nationalist. He gained the favour of Stalin while serving as the head of the OGPU (secret police; precursor to NKVD and KGB) of the Transcaucasus Federation (Armenia, Azerbaijan, and Georgia; the three were united into one republic from 1922 until 1936), and was promoted to General Secretary of Georgia during the 1930s, though he soon effectively became the de facto head of Transcaucasia. He used this to move onto the head of the NKVD in 1938, moving to Moscow, where he stayed until his downfall and execution in 1953.\nIn Tbilisi (the capital of Georgia and Transcaucasia) and later Moscow, Beria brought his own associates, promoting them to power. Many of them were ethnic Mingrelians like himself, and this clique was known for their ethnic heritage. When Stalin started to turn against Beria, he launched a purge against Beria’s group, an event known as the “Mingrelian Affair,” and saw many of his people replaced by those loyal to Stalin rather than Beria.\n\nBeria also saw the mass settlement of ethnic Mingrelian and Georgian farmers into Abkhazia. This was ostensibly done to help cultivate land there, but was more to do with eliminating a rival to Beria: Nestor Lakoba, the head of Abkhazia and a close ally of Stalin. The ethnic Abkhaz had a bare majority in the 1920s, and Lakoba enjoyed immense popularity in his region, which was jokingly called “Lakobistan.” As noted Stalin would vacation there yearly, staying with Lakoba, which made Beria uncomfortable with someone else being so intimate with the leader. So he had Lakoba poisoned in 1936 and started his policy, which was effectively ethnic cleansing: thousands of Georgians were brought to Abkhazia in order to disrupt the demographic balance, and it crushed the Abkhaz leadership and brought it firmly under Georgian (read Beria’s) control, though that only led to resentment and further issues down the road (see 1992-93 and 2008 wars in Georgia).\n\nAn avid soccer fan, Beria was also not afraid to extend his influence to that realm. As head of the NKVD he was de facto in charge of the Dinamo sports clubs, which were a part of the NKVD apparatus. This included the famous Dinamo Moscow team, and the Georgian Dinamo Tbilisi. Beria exerted influence to ensure top players joined the Moscow and Tbilisi club, and was not afraid to imprison those who defied the “invitation” to either club. Not surprisingly Dinamo Moscow was one of the top clubs in the 1930s and 1940s, while Dinamo Tbilisi soon rose to prominence as well."
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43orq4 | Why did the Romans call the Greeks Graeci/-ae while the Greeks called themselves Hellenes? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/43orq4/why_did_the_romans_call_the_greeks_graeciae_while/ | {
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"The original form of the Latin was not actually *Graecus* but *Graius* (plural *Graei*)--*Graecus* appears to be an expanded form imitating the Greek suffix \"-kos.\" It appears that the name was taken from a Greek-speaking people bordering some Italian settlement and was later applied to the entirety of Greek-speakers (much the way that in Herodotus \"Medes\" generally refers to Persians and Iranian-speakers in general). The history of the term, though, is pretty uncertain and was confused even in antiquity. The Γραικοὶ were apparently a Thessalian people (like the Hellenes--Hellas was originally the term for an area of Thessaly on the river Spercheus) and were from an early date considered to be somehow related to the Hellenes, but how was never satisfactorily explained. A Byzantine scholar, quoting Hesiod, claims that original eponymous ancestor of Greek-speakers was not Hellen but a certain Graecus, whose brother was Latinus (contradicting a different tradition on Latinus' birth) and whose parents were Deucalion's daughter Pandora and Zeus. This would make Graecus Hellen's nephew, although another Byzantine scholar descends Graecus from Thessalus. Aristotle also says that originally the Hellenes were called Γραικοὶ, as does an inscription from the 4th Century. But ancient ethnographies are muddled at best, and these probably represent some sort of mythological connections that may or may not have any basis in reality and are probably not being fully understood by the authors mentioning them (Aristotle in particular seems to be thinking of the Graeci and Hellenes as being confined to Thessaly). In the historical period whoever these Thessalian Γραικοὶ were they had ceased to exist, although the Parians were called Γραῖκες and, being Aeolians, were possibly descended from this tribe. But none of this makes sense with the fact that the original Latin is *Graius*, not *Graecus*, and there appear not to be any Greek ethnic terms that lack the \"-kos\" ending and resemble *Graecus*. There are a few place names, but they don't seem to be related and are too far south. So basically the answer is...we don't really know. It used to be thought that when the Italians first encountered the Greeks back in the Archaic Period they were still known as Γραικοὶ (certainly Hellenes had not taken root yet) and that the word eventually was simply transmitted to Latin. But that doesn't seem to make much sense. The Romans must've got it from some small Greek tribe in Italy living next to an Italian people, but we don't know who they were or how the name was transmitted "
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alpmw1 | Do molecules actually look like their displayed formulae? | Sorry if this is a stupid question, but we've been studying hydrocarbons at school and I was wondering if, under an incredibly high magnification and resolution microscope, would the hydrocarbon molecules look anything like the shape we have been taught to draw them as? | askscience | https://www.reddit.com/r/askscience/comments/alpmw1/do_molecules_actually_look_like_their_displayed/ | {
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"No depiction of atoms or molecules really portray them in any real sense. In fact at that size \"appearance\" doesn't really make sense. The particles making them up exist only as these \"vibrations\" that we describe with the quantum mechanic wave functions. These rather abstract wave functions describe the probability distribution of where the \"particle\" is located should we \"look\" for it. But before looking it actually exists everywhere. And the act of \"looking\" for it changes it...\n\nThe most meaningful depiction of atoms and molecules, is by plotting the distribution density as sort of clouds of where the particles could be within a certain percentage. But this is in no way a real depiction of something visible.",
"You can't use normal light microscopes to see molecules. They are too small. There are other methods, such as x-ray crystallography and AFM, that can visualize certain aspects of molecular structure. \n\nThe way we draw structural diagrams is a kind of short-hand to describe the connectivity and bonding between atoms in molecules. The diagrams, necessarily being \"flat\", don't tell the whole picture of how electrons are arranged in a molecule, how close the atoms are to one another, the degree of conformational flexibility a molecule has, etc. But they are good enough to be useful in chemistry.\n\nAs an example, you can compare the structural diagram of R-carvone (on the left at [_URL_0_](_URL_0_)) with a ball-and-stick model derived from its structure in the crystalline state, derived from x-ray diffraction ([_URL_1_](_URL_1_))\n\nIn the case of hydrocarbons, we tend to draw them as neat quasi-linear zig-zagging lines, but in reality they adopt a whole range of conformations formed by rotations around the various carbon-carbon bonds. ",
"You can't see a molecule in the traditional sense, atoms are smaller than the wavelength of light, which means even with the strongest possible microscope you could not see them. And molecules don't move about like large objects, so even if you could 'see' a molecule it would not look like anything that exists in the macroscale world. \n\nBUT - there are ways to image a molecule without looking at it. This [picture](_URL_0_) shows an image of a real (not simulated or computer generated) hydrocarbon. Check out the similarities between the shape taught in school books (A) and the real thing (C). These scientists used an atomic force microscope; basically they cooled the molecule down to almost absolute zero, so it would stop moving around, then they ran a very delicate probe over the surface and 'felt' the molecule, sort of like reading something written in braille. The image is created by measuring the average forces felt between the molecule and the tip of the probe. \n\n\nHere is [another](_URL_1_); the image on the left shows aluminum atoms in a crystal. The image was taken using a transmission electron microscope; this tool shoots a beam of electrons through a very thin piece of material and then look at how the electrons deflect from a straight angle. Scientists then use measurements of those angles to create an image of the material. Here on the left you can see individual aluminum atoms and compare their crystal structure to the predicted image on the right. "
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"https://www.researchgate.net/profile/Axel_Voigt/publication/220395826/figure/fig1/AS:339532940627987@1457962369698/On-a-TEM-image-left-light-dots-render-atoms-from-a-single-atom-layer-of-aluminum-in_W640.jpg"
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oym0w | Do infants with talkative parents develop language skills faster? | Friends of ours are very passive and speak very little - when we come and visit and are very loud and talkative they say their baby is often surprised by all the noise/talking. Made me think of this question.
Bonus question: Do different languages show development at different stages? i.e.: babies belonging to one native language group develop skills faster than babies of some other group, on average. | askscience | http://www.reddit.com/r/askscience/comments/oym0w/do_infants_with_talkative_parents_develop/ | {
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"_URL_0_ \n\nThis might help some. It's really interesting if anything.",
"No, I don't believe there is any evidence of this (although I would love to be corrected). Language seems to develop (in \"normal\" kids) at a pretty constant rate across cultures, similar to learning to sit up, crawl, and walk. Exposure doesn't seem to affect rate of development.\n\n However, [one famous study in language development](_URL_1_) did investigate the relationship between a child's exposure to language and their eventual linguistic abilities. Specifically, they studied differences in exposure as a function of class, and found that \"children in professional families heard more words per hour, resulting in larger cumulative vocabularies.\" For specific numbers:\n\n > In professional families, children heard an average of 2,153 words per hour, while children in working class families \nheard an average of 1,251 words per hour and children in welfare-recipient families heard an average of 616 words per \nhour. Extrapolated out, this means that in a year children in professional families heard an average of 11 million words, \nwhile children in working class families heard an average of 6 million words and children in welfare families heard an \naverage of 3 million words. By kindergarten, a child from a welfare-recipient family could have heard 32 million words \nfewer than a classmate from a professional family. \n\n\n > By age three, the observed cumulative vocabulary for children in the professional families was about 1,100 words. For \nchildren from working class families, the observed cumulative vocabulary was about 750 words and for children from \nwelfare-recipient families it was just above 500 words.\"\n\nSo even though all children seem to develop linguistic competency at a similar rate regardless of their level of exposure, there are significant differences in linguistic ability that seem to be related to exposure, that fall along class lines and that tend to either remain constant or increase over time (as a follow up to this study found). \n\n[Here's](_URL_0_) where I pulled the quotes from, it's a summation of the book I linked."
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23c0zt | If I were to grind a solid into a powder down to the molecular level, would it behave as a liquid? | askscience | http://www.reddit.com/r/askscience/comments/23c0zt/if_i_were_to_grind_a_solid_into_a_powder_down_to/ | {
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"I seriously doubt it. There are nano powders that are just tens of nanometers in size and I know from working with them that they still behave like a powder and not a liquid. Size of a solid should not induce a phase change from solid to liquid like temperature or pressure do. I would expect the behavior to be much more like sand or other granular materials than a liquid.",
"Sometimes, yes! There are very fine silica gels that look very much like liquids although they are powders. They're used in Organic labs typically, for things like chromatography. It's worth noting that it really only looks like it's behaving as a liquid, meaning it \"flows\" and takes the shape of its container. However, on the molecular level, it behaves as any other solid would, except it's made of very small solid particles. \n\nBasically, to the human eye, it looks almost liquid, but it's really not."
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avy3l0 | Why did cotton become a symbol for American slavery as opposed to other cash crops or grueling domestic chores? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/avy3l0/why_did_cotton_become_a_symbol_for_american/ | {
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"The key cash crops grown by American slave labor before the 19th century were tobacco and rice. Little cotton was grown in the United States, in large part because separating the seeds from the raw cotton by hand was extremely labor-intensive and time-consuming. In 1793, Eli Whitney invented the cotton gin, which greatly simplified the procedure and made growing cotton much more profitable.\n\nIn the early 19th century, southern planters moved into areas like the Mississippi River Valley and started growing lots and lots of cotton with slave labor. At the same time, industrialization created a huge demand for cotton by textile factories in the North and in England - thus southern cotton plantations became a key factor in the burgeoning global industrial economy, so much so that the region came to be called the Cotton Kingdom.\n\nThe Cotton Kingdom depended on slave labor. Slaves planted, tended, and harvested the cotton. So much of southern planters' money was tied up in land and slaves for cotton production that slaves were often the closest thing they had to liquid capital. Slaves were simultaneously capital, collateral, and the means of production. Historian Walter Johnson puts it in very evocative terms: “The Cotton Kingdom was built out of sun, water, and soil; animal energy, human labor, and mother wit; grain, flesh, and cotton; pain, hunger, and fatigue; blood, milk, semen, and shit.”\n\nCotton became the symbol of American slavery because cotton grown by slave labor in the American South comprised a large part of the raw material that powered the global economy. By 1860, the South produced 2/3 of the world's cotton.\n\nAs the nation edged closer to Civil War, many southerners expected that the demand for cotton would help secure southern independence. It didn't, but that's a story for another time.\n\nSources:\n [The Economics of Cotton](_URL_0_)\n\nWalter Johnson, *River of Dark Dreams: Slavery and Empire in the Cotton Kingdom*\n"
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1r73jv | Why did Captain Cook name New South Wales as such? What geographical similarities, if any, did he take note of? | Considering Captain Cook only encountered the coast of Australia which seems to me to bear EXTREMELY minimal resemblance to South Wales, why is this the case? It seems to me that the resemblance it does share is really only owing to the fact that it has beaches and headlands, much like any coast. It would be feasible to me if he encountered the rolling rocky hills near the blue mountains and glasshouse mountains which do resemble Wales to a considerable degree, but, at least to my knowledge he almost certainly never ventured that far inland. | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1r73jv/why_did_captain_cook_name_new_south_wales_as_such/ | {
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"Australian history isn't my field, so I can't speak to the specific case of New South Wales in Australia. I do know that the name \"The New Principality of South Wales\" was assigned to the southern coast of Hudson Bay (in present-day Canada) by Welshman Thomas James in the 1630s. The question of why Cook chose NSW seems to be more uncertain. I know we have a couple of Australia experts around here, so hopefully someone who can shed some more light on this will see this question.\n\nIn addition, I can point out as a matter of general interest (maybe?) that, in general, the mapping and naming of places in Australia, as in other colonies, was part of the act of claiming and ultimately taking possession of land that was inhabited by Indigenous people and was also being contested between rival expansionist powers in the Pacific. Mapping and naming were means of symbolically conceptualizing these areas as new edges of empire(s), even before any actual European settlement had taken place. By assigning place names with ties to Britain or even to their own personal lives, for example, colonizers like James Cook and Matthew Flinders imagined these areas as part of the British Empire. This process played into the geopolitical tensions between imperial states that defined European politics at this time, especially between England, France, and Spain, whose colonizers often mapped their *own* conceptualizations of these spaces through French and Spanish lenses and points of reference -- in direct contest with their British counterparts. Significantly, naming places in these ways also marked a significant element of colonizers' attempts to imagine/racialize these as white spaces.\n\n**Refs:** \n\nPenelope Edmonds, *Urbanizing Frontiers: Indigenous Peoples and Settlers in 19th-Century Pacific Rim Cities*, (Vancouver: UBC Press, 2010), esp. 22-26.\n\nAdele Perry, *On the Edge of Empire: Gender, Race, and the Making of British Columbia, 1849-1871*, (Toronto: University of Toronto Press, 2001).",
"It would appear to be named after Wales, not South Wales - in Cook's original journals - found here: _URL_0_ - he calls it simply New Wales:\n > I now once More hoisted English Colours, and in the Name of His Majesty King George the Third took possession of the whole Eastern coast from the above latitude down to this place by the Name of New Wales\n\nIn later copies sent to the Queen and the Admiralty it is changed to New South Wales.\n\nHowever he doesn't really give any reason in that section, and in his descriptions he doesn't really compare it to Wales, but the prevailing theory is that it must have reminded him of Wales in some way...\n\nOn the Glasshouse Mountains, from the same journal, from before he named it New Wales:\n\n > These hills lay but a little way inland, and not far from Each other; they are very remarkable on account of their Singular form of Elivation, which very much resembles Glass Houses,‡ which occasioned my giving them that Name. "
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5e3s76 | Why does Aluminium foil make so much noise when manipulating it ? | Hi Reddit !
Ok so I was making a ball for my cat and when I was doing so I wondered why did the aluminium foil make so much damn noise, hope you can answer to it, have a nice day ! | askscience | https://www.reddit.com/r/askscience/comments/5e3s76/why_does_aluminium_foil_make_so_much_noise_when/ | {
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"I don't know, but I found [this discussion](_URL_0_) about acoustic emissions in metals interesting.",
"It's a thin metallic membrane that reflects sound waves efficiently. The numerous sound waves generated by the metallic surfaces striking one another during the process of balling up the foil cause the noise. It is similar to the sound of balling up paper but not as pronounced because foil reflects the sound waves more effectively."
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1x5bqq | What happens to an ant colony if its Queen is artificially removed? | I recently watched BBC's ["Planet Ant- Life Inside The Colony"] (_URL_0_) and after watching it I wondered what happens to the biological machine (the ant colony) after its Queen is gone.
* Is there a second in command who will grow to the size of a Queen via chemicals?
* Do they spread out in search of a new Queen to serve?
or.. * Does the colony just die out due to the lack of a Queen?
| askscience | http://www.reddit.com/r/askscience/comments/1x5bqq/what_happens_to_an_ant_colony_if_its_queen_is/ | {
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"It depends on the species of ant. Harvester ants (large, red and slow) from Arizona will never raise a new queen, so the colony will die within about two years (which is the average lifespan of a worker). One quheen per colony. For reference, their queen lives for 20-25 years.\nArgentine ants (small, black, invasive species) have many queens, and make more as they go. They are robust to losing a few.\nSource: several years of undergraduate research on ants.",
"There's a species of ant in which the absence of a hormone from a queen will cause the workers to develop secondary sexual characteristics and start laying eggs. All the eggs will be haploid, as they are not fertilized. The colony will continue to harvest resources and produce as many offspring as it can until it dies. The electric ant, among other species, actually do this at the drop of a hat, even in the presence of a queen, but this species is very \"distributed\" they don't have a central nest. \n\nOther ants will just rear what young are still in the nest and then continue to collect resources until they die.\n\nSource: I'm interested in ant behavior as a way to solve problems, per-species strategies are very very varied and I like to read about it; I'm also a hobbyist myrmeculturist (not sure if it's a word, but I keep ants).",
"Apologies if this has always been asked, I don't have time to skim the while thread and an curious to ask a question :\n\nI used to have an ant farm, which is a thin plastic case with sand inside. As there is no queen in the farm does that mean the ants are doomed to an extra short life? Would they be confused and continually searching for her? ",
"I'm going to try to answer this but as the thread has been us a while I'm not sure anyone will see it.\n\nSome colonies of ant will be in a bit of trouble if the queen dies. However there is a very wide variety of reproductive strategies that the different species employ. The best way to think of it is like a spectrum. Massive ant colonies that have a single reproductive individual that all the workers 'serve' is just one end of the spectrum. At the other end there are 'queen-less' species of ant, that is, colonies that have no morphologically distinct reproductive cast. In these colonies the reproducing individual is just a dominant worker who polices her subordinates. A good example of 'queen-less' ants are Dinoponera. How do they form new colonies? Basically if a colony gets big enough they just split in two. Harpegnathos saltator is a good example of an ant that is sort of between the two, their colonies have queens, they found the colony and act as the sole reproducer, until they die, once they die they are replaced by the dominant workers; the gamergates. These will carry on reproducing and in theory the colony can be immortal.\n\nWhy do they employ all these different strategies? It comes down to the environment they inhabit and by extension what resources they have evolved to exploit.\n\nIf you want to know more for yourself read The Ants by E O Wilson and Bert Holldobler.\n\nI hope this has answered your questions.\n\nTL;DR It depends on the ant.\n\nEdit: spelling and grammar. ",
"So, honeybees are not ants but have similar social structure with a queen and different classes of non reproducing workers. I do not know but would think it likely that some ants would react similarly to honeybees. First, if there are fresh eggs or newly hatched larva, the workers feed them a special diet \"royal jelly\" that turns the larva into queens instead of workers. In this way a colony can grow a new queen. Second, a worker may start laying eggs. All workers are female but only the queen has mated so any individuals hatching from those eggs will be male drones. Basically the colony will still die in this latter case but it will send its genes into the world to mate with other colonies",
"I think the real answer was: nothing. They don't wonder off, and they don't riot in the streets at the absence of order. Ants do what they do--if anything it argues for the notion of \"super organism,\" insofar as the queen is just the sex organ/cell regenerator: a dog's organs carry on normally after it is neutered....although, I think I remember my first dog looking everywhere for his balls. \nAnd if existance depends on young replaceing old, and there are no more young, then there is no more exisitance.",
"This is somewhat unrelated, but it's a little misleading to say that the colony \"serves\" the queen. She acts as little more than a breeding machine for new workers. \n\nThe workers themselves are the actual guiding influence of the hive, with thousands of sisters working together to ensure the queen produces more female siblings. \n\nAt first, you'd think this is counter intuitive to their genetics and they should pursue their own offspring, but in fact by maintaining the queen's genetic line they ensure genetic fidelity better than they would running off to hatch their own brood. \n\nThis issue is at the heart of most ant behavior, and offers an explanation for why individual organisms are prepared to throw their life away for the benefit of the hive.",
"Ok, i'm about to break a few rules but I am really curious. \n\nWhen I was a kid (like 8-10) there was a black ant colony in/under an oak tree right in front of my house. One day a Queen emerged with what i can only say was \"a bodyguard\" ant. They ended up in the garage and just to see what would happen, I crushed her. \n\nWithin 30 mins the front area of my house is covered in black ants.\n\n I live in MN, they could have been carpenter ants. \n\nJust wondering what the swarming behavior would have been, and why a Queen was out and about for a stroll? ",
"Buried down in the comments it shall go, but...I'm watching the documentary now! Fascinating really. My question is: Since all these leaf cutter ants are mostly female with only the occasional males who mate with the queen, is there any reason for the worker ants to have a sex? How is it that they are considered female? Do they have reproductive organs, but just don't use them?"
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b213nz | Question from my daughters; If I were to travel back in time could I survive in the same atmosphere as the dinosaurs and find nutritious foods that wouldn't kill me (could I consume a dinosaur)? | I'm assuming that the air may be a bit different in oxygen to nitrogen levels. And when I was asked if we could find food...I didn't have a good answer.
Edit: Thanks for all the awesome answers! Apparently they are now wanting to visit the local library to get some more info. Thanks Reddit! | askscience | https://www.reddit.com/r/askscience/comments/b213nz/question_from_my_daughters_if_i_were_to_travel/ | {
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"Time of the dinosaurs covers an incredibly immense period of time, of course.\n\nAngiosperms, or trees that bear fruit, began evolving in the late Cretaceous, about 125 mya. On top of that, the fruits and vegetables we have today are highly domesticated and wildly different from their natural forms. So you wouldn't find, say, apples like you know them. The plant life that dominated the landscape were ferns, which can be edible, and cycads, which are generally inedible unless cooked or if you only eat the seeds and young leaves. \n\nLarge dinosaurs commanded the landscape, but there were much smaller creatures too; small dinosaurs, avians, lizards, early mammals, fish, insects. If you are willing to hunt and you are not a picky eater, any one of these could make a meal. Dinosaurs are essentially non-avian birds, and would likely be similar in taste to, well, chicken.\n\nThe temperature was overall hotter by about 10°C, and CO2 levels were higher. You could breathe, but you would be very uncomfortable. \n\n & #x200B;",
"Apparantly there were giant dragonflies then needing lots of oxygen to be pumped through their trachea, oxygen was in high supply, which could explain the bigger size of organisms. It might take some adjustment for present day men to these levels of oxygen. As for food, at a certain stage, of course there were already those small mamalian animals present that would later on survive after the giant meteorite hit the earth and triggered the demise of the dinosaurs. So meat would be plenty in supply, you could even eat crocodile back then, but concerning vegetation based food, It would be nearly impossible when you were teleported in that bygone age to tell what was edible, unless you co-evolved from animal to human alongside with the vegetal species like bees and flowers."
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3h0v0m | Are there any sources you would recommend for covering the decline of the Ottoman Empire? | Hi r/askhistory! At my (British) school, we do an independent research project, and am thinking of choosing a topic that fascinates me in its under-reportedness- the Long War of 1591/3-1606, and its effect on the Ottoman Empire. My exact (working) title is TO WHAT EXTENT DID THE LONG WAR SIGNAL THE BEGINNING OF TURKISH DECLINE? Unfortunately, this means that research is rather hard. I managed to find SOMETHING, but it wasn't really enough, and I also found a book to buy that I have now forgotten (Somebody Taylor is the author?). I need help! Are there any good (English- I'm afraid I cant speak any other languages well enough to read an academic book) sources that you would recommend? The sources could be about the Long War in particular or just about the general decline, but any help would be much appreciated. By the way, if I am barking up completely the wrong tree, please don't hesitate to tell me- it is just an idea (and maybe suggest other related ideas?). Thank you very much everybody! | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/3h0v0m/are_there_any_sources_you_would_recommend_for/ | {
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" I'd check the bibliography of Lord Kinross' \"The Ottoman Centuries\". Of course, he focuses like most on the period after the suppression of the Janissaries as the time of Ottoman decline...",
"Turkey: A Modern History starts later than you like, but could be useful in your EP to compare when the Ottomans started declining, as the Ottoman decline is covered in roughly 2/3 of the book, but it starts in the 1700s"
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29dcfr | If all muscles work through contraction, how do people expand their lungs to breathe in? | askscience | http://www.reddit.com/r/askscience/comments/29dcfr/if_all_muscles_work_through_contraction_how_do/ | {
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"At the bottom of your lungs is a muscle called your diaphragm. When that contracts (like any other muscle) it pulls on the gas bags that are your lungs, making them larger, creating a region of lower pressure and air rushes in. Kinda like how pulling the plunger of a syringe sucks stuff into it.",
"Your lungs expand due to the fact that they are exposed to negative pressure from your diaphragm. [Here's a video](_URL_0_). When you breathe in, or inhale, your diaphragm contracts and moves downward. This increases the space in your chest cavity, into which your lungs expand. The intercostal muscles between your ribs also help enlarge the chest cavity. They contract to pull your rib cage both upward and outward when you inhale.\n\nWhen you breathe out, or exhale, your diaphragm relaxes and moves upward into the chest cavity. The intercostal muscles between the ribs also relax to reduce the space in the chest cavity.\n\n\n ",
"Also just in addition to the comments above, the lungs (whilst contaning some smooth muscle) aren't really muscular, just sacks o' flesh that act like large balloons. They themselves don't really do much contracting, the diaphragm and chest wall movements contribute the most effort to breathing. ",
"You can think of your pleural cavity like a vacuum during inhalation and a balloon during exhalation.\nDuring inhalation, as said before, muscles such as the diaphragm and intercostals contract to create a negative pressure within the pleural cavity. This essentially turns your pleural cavity into a vacuum that will suck in air from the only point that it can, the environment through your nasal and oral cavity. \nDuring exhalation, the pleural cavity is now like a balloon full of air and the muscles and bones around the pleural cavity (diaphragm, intercostals, and ribs) act as hands that will apply pressure to the balloon and push air out by creating a positive pressure in the pleural cavity. The diaphragm relaxes to apply pressure from the inferior side while the contraction and relaxation and contraction of certain intercostals (we have many different types of intercostals) cause the ribs to depress and apply pressure to the pleural cavity from the lateral, ventral, and dorsal sides. ",
"You expand your diaphragm, increasing the volume of your thoracic cavity, which then lowers the O2 pressure inside of your lungs lower than that of atmospheric O2 pressure, causing air to passively enter your open airways."
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3zllax | What is a book on the former Imperial German colonies? | Written in English and/or German | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/3zllax/what_is_a_book_on_the_former_imperial_german/ | {
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"Are you looking for books on the colonies before or during World War I? Empires at War: 1911-1923 has a chapter by Heather Jones on the German Empire. Absolute Destruction by Isabell Hull discusses Germany's colonial policies in Southwest Africa. I know Germany had colonies in the Pacific but I have no suggestions for those colonies. ",
"Even though I haven't read it, i've heard that it's good; *The Kaiser's Holocaust: Germany's Forgotten Genocide and the colonial roots of Nazism* by Casper Erichsen and David Olusoga. \n\nOther books could include Thomas Pakenham's *The Scramble for Africa* and John Rohl's *Kaiser Wilhelm II 1859-1941: A Concise Life*. If you prefer to read in German, Rohl's books are also available in German. "
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3kgh0w | how long does holy water stay holy? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3kgh0w/eli5_how_long_does_holy_water_stay_holy/ | {
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"Any water blessed by a priest is Holy Water. \n\nIt's mostly used for anointing something. We would dip our fingers in Holy Water and do the sign of the cross when entering and exiting mass, for example. People get baptized in holy water, or the priest would splash holy water on the congregation during certain ceremonies.\n\nGenerally, you don't drink it. You're not supposed to. There's nothing that says anything special or bad will happen to you if you do drink it, though- from what I remember.\n\nI remember a child drinking holy water once in church, and everyone thought it was just a cute kid thing. He wasn't cast out and called a heathen. \n\nNo, it wouldn't be \"holy urine\" when you peed it out.\n\nI honestly don't know about diluting it. I would assume it just wouldn't be considered holy water anymore.",
"I believe you are taking it too literally. \n\nHoly water is water that has been blessed by a priest to be used in various traditions (baptisms, holy cross when entering church, etc). \n\nHoly Water should only be disposed through regular use, or by disposing of it in a special container. I would imagine that using holy water to water plants, diluting holy water or drinking holy water would fall under the \"improper disposal\" category.\n\nThat being said, there is no holy water police, so traditions may vary from family to family and region to region. ",
"Like all religious things, it comes down to faith. Catholics believe the water to be holy because a priest blessed it for use in special rituals. Obviously it's not like the water went through some molecular transformation and I'm sure you know that. \n\nI think you are probably trying to poke fun at this matter of faith (and as an aetheist myself, I understand the urge) but it's considered holy as long as the people who believe in it consider it holy. Tautology! \n\nIt doesn't do shit to vampires because they don't exist. Your plants won't grow any better or be more blessed, and your half & half holy water would probably be thought of as now being unholy just because you are fucking around with it.\n\nIt's like the idea of the wine becoming the blood of Christ. How long does it stay bloody? The premise itself is outside of faith. "
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3ix8gi | If a black hole were to only be 'fed' electrons (or particles of like charge), would the electrostatic charge inside eventually destroy the black hole? | askscience | https://www.reddit.com/r/askscience/comments/3ix8gi/if_a_black_hole_were_to_only_be_fed_electrons_or/ | {
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"It might be impossible to do so.\n\nSpecifically, you are asking if it's possible to pour electrons in a black hole until it becomes superextremal, that is, the charge becomes larger than the mass. The geometry of a charged, spherically symmetric black hole is described by the Reissner-Nordström metric, and for a superextremal black hole that metric predicts a naked singularity. That is, information flows from the singularity into the external world, instead of the normal direction. Some believe this to be impossible in the sense that it does not happen, which is the cosmic censorship conjecture (see also the Thorne-Hawking-Preskill bet).\n\nIf the conjecture is true, some mechanism (classical or quantum) prevents you from accreting more electrons into an almost extremal black hole. Is possible that the force between an almost extremal black hole and an electron is repulsive rather than attractive. It's well-known, for example, that the force between two extremal black holes is zero, and the electron, would be superextremal if it was a black hole. Or, the well-known firewall inside the charged black hole has something to do with it.\n\nSome people think of the conjecture to be false.\n\nHowever, even if the general conjecture remains a conjecture, I'd be surprised if nobody had investigated the specific case of charged black holes. I'm sure there's some good results, but I never read about that. You could research literature in extremal Reissner-Nordström black holes.\n\nEDIT: see the analogous discussion for Kerr (rotating) black holes, where the same relationships hold with angular momentum in place of the charge. If you have an almost extremal black hole, and try to launch an object in with the angular momentum to make the hole reach extramality, you find that the object has too much angular momentum to fall in, and slings back out. Something similar must happen with the charged particle and the Reissner-Nordström hole."
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10pslh | Regarding the Lincoln-Douglass debates, is this just good politics or is Lincoln a racist? (I know, it sounds like a loaded question, but I seriously want to hear a historian's opinion on it.) | I was talking with another Redditor in a comment thread, and he cited that Lincoln was a racist via this quote at the Lincoln-Douglass debates-
> “I will say then that I am not, nor ever have been in favor of bringing about in anyway the social and political equality of the white and black races – that I am not nor ever have been in favor of making voters or jurors of negroes, nor of qualifying them to hold office, nor to intermarry with white people; and I will say in addition to this that there is a physical difference between the white and black races which I believe will forever forbid the two races living together on terms of social and political equality. And inasmuch as they cannot so live, while they do remain together there must be the position of superior and inferior, and I as much as any other man am in favor of having the superior position assigned to the white race. I say upon this occasion I do not perceive that because the white man is to have the superior position the negro should be denied everything.”
So I guess my question would be, is this just good politics or is he actually a racist? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/10pslh/regarding_the_lincolndouglass_debates_is_this/ | {
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"[Presentism](_URL_0_), if you do it, you're gonna have a bad time.\n\nWas Lincoln racist by modern standards? Hell yes, but *everyone was*.\n\nIt's better, when broaching this subject, to point out that Lincoln was not an abolitionist, promoting full equality for blacks, but rather antislavery. He thought it deplorable that black people were forced to labor not for their own benefit but rather for someone else (the master). He greatly advocated economic freedom for blacks so that they could determine their own destiny and also to preserve white Northern labor from the threat of competition from Southern slavery. This reflected the majority of Republican opinion at the time. By the end of his presidency Lincoln had developed new opinions regarding race and the future of the country, and would approach a much \"less racist\" mindset by modern standards.\n\nThat quote is also quite cherry picked, sitting on its own there. Take for instance another Lincoln quote:\n\n > I want every man to have the chance - and I believe a black man is entitled to it - in which he can better his condition, when he may look forward and hope to be a hired laborer this year and the next, work for himself afterward, and finally to hire men to work for him. That is the true system."
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25fcpw | is it possible for humans to choose their own personalities? | This seems a bit philosophical… There is no limit for age of the individual (early adult/later in life). I am just curious in general.
Does the individual have agency in personality change?
Any personality psychologists out there?
| explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/25fcpw/eli5is_it_possible_for_humans_to_choose_their_own/ | {
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"There are some things you can't change. For instance, I am a very anxious person. I don't like that about myself, but I can't just stop being one. With a lot of personal effort and some counseling, I will become a slightly less anxious person, but it's still a root element of my personality that can't be chosen or unchosen. I imagine everyone has some aspects like this."
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5nua75 | is there a science behind photographers telling us to say cheese? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5nua75/eli5_is_there_a_science_behind_photographers/ | {
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"The \"eeeeeeeeeeeeee\" bit results in a kinda-natural looking smile. And everyone knows that word, it's a very common word with a drawn out long e sound.\n\nIf you tell people \"make a natural smile\" you get everything from \"not a natural smile\" to \"please dont eat me.\" "
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e7scmc | what is pencil tip made up of? lead or graphite or both? why? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/e7scmc/eli5_what_is_pencil_tip_made_up_of_lead_or/ | {
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"It contains no lead at all. It's made of graphite. The term \"pencil lead\" is only a reference to graphite's color, which is similar to lead's color.",
"There is no lead in pencils. Rather, the core is made up of a non-toxic mineral called graphite. The common name “pencil lead” is due to an historic association with the stylus made of lead in ancient Roman times.",
"There's no lead, it's a mixture of graphite and clay. The graphite makes the mark, and the clay is mixed in various proportions to alter the hardness of the pencil."
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9yhdqh | when you're awaiting surgery why will they not even let you have a glass of water if you're thirsty as hell? why aren't all the iv fluids quenching the thirst anyway? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9yhdqh/eli5_when_youre_awaiting_surgery_why_will_they/ | {
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"If you throw up while you’re asleep you can choke to death. IV fluids are all salt water, they keep you hydrated but don’t keep you from getting thirsty.",
"You can't drink anything because there is a chance you may regurgitate whatever is in your stomach as your body's reflexes are stopped while under anesthesia. If regurgitation happens whatever is in your stomach is pushed back up into your throat and mouth which you could accidentally inhale, causing you to suffocate or it can make its way into your lungs and cause pneumonia or something similar. The reason the IV doesn't quench thirst is because thirst is usually a feeling of your mouth being dry and your brain being triggered by this causes a feeling of being thirsty. So you can be hydrated and still be thirsty at the same time. ",
"When giving you anesthesia one of the major issues is people throwing up and, by virtue of being unconscious, breathing in their vomit into the lungs. That is a very bad thing, potentially deadly, and reducing the amount of fluid in the stomach reduces the danger. "
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acfjrs | how do locks and keys work when it comes down to uniqueness? is every lock-key combination unique? or could i get lucky and could i find another door or bike lock that matches my key? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/acfjrs/eli5_how_do_locks_and_keys_work_when_it_comes/ | {
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"Great minds think alike. I may have found yer answer, matey. Yer not alone in askin', and kind strangers have explained:\n\n1. [ELI5: Is each lock and key combination unique, or do I share the same house key as a bunch of other people? ](_URL_2_) ^(_83 comments_)\n1. [ELI5: How are keys unique? There must be millions of doors out there. Do \"overlaps\" happen? What are the odds that my key will open a random door in the same city? ](_URL_3_) ^(_18 comments_)\n1. [ELI5: if every lock is unique and requires a different key to open in, how does a skeleton key open any lock? ](_URL_0_) ^(_6 comments_)\n1. [ELI5: is every house key completely unique? How is this done? ](_URL_7_) ^(_11 comments_)\n1. [ELI5: Does every single car in the world have a unique key? ](_URL_8_) ^(_37 comments_)\n1. [ELI5: How do padlock companies make so many locks, yet ensure that your key only opens your lock? ](_URL_4_) ^(_43 comments_)\n1. [How are there enough variations for keys that every key in the world can only unlock it's specific lock? ](_URL_1_) ^(_18 comments_)\n1. [ELI5: How do lock makers mass produce locks that can only be opened with one key? ](_URL_5_) ^(_12 comments_)\n1. [ELI5: How are locks/keys made so that no other key works in any other lock? ](_URL_6_) ^(_8 comments_)\n",
"Locks have a set of pins. These pins have a break in them. Keys lift the break in the pins to line up with the barrel of the lock allowing it to rotate. Rotating the barrel then moves the bar of the lock out of the way. Typically a lock will have 4 pins, but there is no limit. I've seen single pin locks and dozen pin locks. \n\nSo is every combination unique? No. I have a masterlock with 4 pins, it looks like each pin has 10 possible break points, meaning there are 10^4 possible keys for that lock. If they've sold more than 10,000 of those locks there are duplicates out there. \n\nIt gets more complicated though -- keys also have a shape. You can't just put any key in any lock. Some keys are round, some are straight, some are dimple based....then there are the fancy locks that have discs not pins.\n\nThen as locks get old the tolerances get looser. You start finding that keys that didn't used to work start working on a lock. Eventually even a simple screwdriver will turn a lock. ",
" > **Is every lock-key combination unique? Or could I get lucky and could I find another door or bike lock that matches my key?** \n\nMost key-lock combos are unique, but there are some exceptions. Many locking file cabinets use the same key or one of just a few keys, as do a lot of those intercom/security panels on buildings that require a code to get in. There are some YouTube videos about physical penetration testing that give more information.\n\n & #x200B;"
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4n04gm | What would the written language of the Mali Empire have been? | I am a sixth grade teacher looking to help a student. My kids are doing a project on a civilization of their choosing, and despite a lot of effort we cannot find any info on the written language of Mali. I'm assuming Arabic, I know it was a linguistically diverse empire but I don't know if the other languages were written at that point. | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/4n04gm/what_would_the_written_language_of_the_mali/ | {
"a_id": [
"d3zq0sz"
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"I think most of the writing that's survived in the sahel is arabic, the mauritanian manuscripts are and the most famous timbuktu manuscripts are too.\n\nHowever, according to University of Cape Town the Timbuktu manuscripts do also contain works in Songhay, Fulfulde, Tamasheq and Hausa. \n\nThe problem is the manuscripts aren't all from the mali empire time, some are from later and some earlier and as far as I am aware they haven't been catalogued enough for anyone to be able to say for sure when those languages were first used and if that was after or before the mali empire lost timbuktu (Timbuktu was recently captured by islamic rebels and the cape town university group working at it lost funding so a lot of work is still to be done in studying the manuscripts).\n\nPossibly someone who'd actually been to timbuktu would be able to tell you for sure."
]
} | [] | [] | [
[]
] |
|
70mzfk | why is there such a loud sound when we clap? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/70mzfk/eli5_why_is_there_such_a_loud_sound_when_we_clap/ | {
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"You're compressing the air between your hands rapidly, creating a pressure wave. Which is, you know, what sound is.\n\nThe best, loudest claps involve cupping your hands to trap more air between them. Your hands squeeze that air together before it rapidly expands again out through the gaps between your hands. That rapid compression and expansion is the sound wave that your ears detect. The more air you compress, the faster you compress it, and the harder you compress it, the louder the sound will be.\n\nCompare that to, say, clapping with wide open hands, palm against palm, and you won't get much of a sound, not matter how hard you clap, especially if you can get the heel of one palm into the center of the other so very very little air is trapped. You'll get a smacking sound, but that's mostly the sound of your skin smacking and vibrating the air, rather than a good solid compression of air like in a proper clap."
]
} | [] | [] | [
[]
] |
||
npl4x | Can an asthma inhaler benefit someone who doesn't have asthma? | askscience | http://www.reddit.com/r/askscience/comments/npl4x/can_an_asthma_inhaler_benefit_someone_who_doesnt/ | {
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"what drug is it? I know that atrovent (ventolin) opens your air ways significantly and is used by runners and weight lifters. However it's not a corticosteriod; which is what you have from the sounds of it. I used an inhaler to reduce phlem build up from envriomental triggers ( i ran a stone saw here on the canadain sheild for a year before schoolio)\n\n_URL_0_",
"what drug is it? I know that atrovent (ventolin) opens your air ways significantly and is used by runners and weight lifters. However it's not a corticosteriod; which is what you have from the sounds of it. I used an inhaler to reduce phlem build up from envriomental triggers ( i ran a stone saw here on the canadain sheild for a year before schoolio)\n\n_URL_0_"
]
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"http://www.webmd.com/asthma/inhaled-corticosteroids-for-long-term-control-of-asthma"
],
[
"http://www.webmd.com/asthma/inhaled-corticosteroids-for-long-term-control-of-asthma"
]
] |
||
1d76ak | why does lettuce, the white part, get all brown and slimey? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1d76ak/eli5why_does_lettuce_the_white_part_get_all_brown/ | {
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"text": [
"It's residue from bacterial decomposition. Basically, the lettuce is going bad (rotting). "
]
} | [] | [] | [
[]
] |
||
ika6r | Is it possible to create a self powered battery using magnets? | Yes is this is a repost of same idea just explained a bit better. If four neodymium magnets were placed diagonally around a sturdy piece of metal wrapped in copper wire, with a rotatable ring surrounding the inner ring containing four neodymium magnets facing the inner magnets at a + + or - - also with copper wire surrounding the inner magnets. Would this create unlimited energy. Hard to explain in text.
[Basic idea](_URL_0_)
If there was copper on the outer ring. | askscience | http://www.reddit.com/r/askscience/comments/ika6r/is_it_possible_to_create_a_self_powered_battery/ | {
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"c24f4v4"
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"score": [
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"text": [
"No, the magnets would just lock in place. Perpetual motion is not possible."
]
} | [] | [
"http://imgur.com/bjVpD"
] | [
[]
] |
|
7bw706 | why is it seemingly impossible to sync your blinker with the car in front of you? even if it's the same make/model? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7bw706/eli5why_is_it_seemingly_impossible_to_sync_your/ | {
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"(This may not be true for all cars, but it has been on the cars I've owned). The on/off blink timing for your turn signals isn't controlled by a chip, its controlled by an analogue circuit that uses the relative resistances of the lights/lamps in it. And even if you get the timing right with the same make/model car, no two light bulbs are identical, so the resistance of your two sets of lamps isn't going to be identical. \n\nHave you ever noticed that when one of your side or signal lights goes out, the blink on that side goes faster? I'm driving around right now with a busted running light and the signal blink on that side is about 50% faster than the other."
]
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[]
] |
||
fzujof | how can people with alzheimers/dementia remember to speak and understand, for the most part, general conversations - but can forget things like their children, to eat, basic personal hygiene, etc? | Are these memories held in different parts of the brain? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/fzujof/eli5_how_can_people_with_alzheimersdementia/ | {
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"Things like speech and understanding are impacted as well, but they are distributed in the brain over many neurons, not necessarily in the same spot, so they are easier to access even with impediments. Specific memories will tend to be localized and it's more likely that the disease can block or destroy them.",
"One doesn't \"remember\" to speak and understand, as in that it is not a memory. Language is a cognitive function in itself, as is memory, and it can also be impacted by dementia. The deterioration of language functions that is associated with dementia or other neurodegenerative illnesses is called Primary Progressive Aphasia. Dementia affects memory first, usually, but it can also impact other cognitive functions and it definitely affects language, but it's often not as early in the progress of the disease and it's often the more complex processes of language that can go away first, hence going undetected for longer."
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|
66o562 | why do athletes get heart attacks? | I've known of two professional athletes that have died of a heart attack in the last few days. Both past their prime but definitely not old either and still fit (retired from competitive sport). why would someone still very fit get a heart attack? If anything id have thought professionally fit people who look after their diet and exercise regularly would be less likely to get cardiac arrest. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/66o562/eli5_why_do_athletes_get_heart_attacks/ | {
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"Exercise and activity is good for your body and for being fit, but athletes by definition go much farther than the state of being fit with the activity that they do. As such it is not uncommon for them to over tax their hearts and lungs, and if they have any kind of damage or defects that can prompt a heart attack. \n\nMany athletes also use various chemical and herbal aids (some legal, some not) to help them in their training and development and some of these aids can cause heart attack as well. "
]
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|
1fo048 | How is exposure to a virus correlated to one's likelihood of getting sick? | I know this may seem like a dumb question at first, but I'll try to explain. From my limited understanding of biology, when a virus enters your body, it sneaks into a cell and tricks it into producing more virii, which in turn infiltrate more cells and so on until your immune system gets the upper hand. That is unless your body catches the parent virus before it has a chance to replicate.
Theoretically, wouldn't your immune system be more likely to spot a swarm of virii rather than a single virus, and thus take action at a much earlier stage?
Another way to ask this question is, if you were to inject a virus into a sample group at different "concentrations", what would the concentration vs probability of illness graph look like? | askscience | http://www.reddit.com/r/askscience/comments/1fo048/how_is_exposure_to_a_virus_correlated_to_ones/ | {
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"The basic idea is kind of the opposite of what you said. More viruses do not mean that they are easier to \"spot\", just that it is easier for them to overwhelm the host's defenses. This concept is called the \"infectious dose\", and it varies by organism (some organisms quickly overwhelm the host with just a few organisms, others take a lot more). There is no curve, as the mechanism of every organism is different.\n\nWikipedia has a list of a few organisms (bacteria, viruses, and protists) with their infectious doses at _URL_0_",
"You have stumbled upon one of the central ideas of microbiology: The reasons that an animal becomes infected are *route* and *dose*. \n\nThe first thing a virus must do when infecting a new host is bind to a receptor on a cell. A specific receptor(s) is required for binding and entry to the cell, and if this receptor is not present, the virus cannot infect the cell. This what leads to what is known as *tissue tropism*, a virus's ability to infect different tissues. Pathogens like influenza bind to receptors in the lungs and other airways, viruses like Norovirus attach to receptors in the gut, etc...\n\nThe second part of this is dose. A sufficient dose of virus must be delivered so as to not be degraded by chemical and physiological processes before replication begins. Cells also have an innate form of immunity; if a small number of cells become infected, this innate immunity can shut down the infection. However, if enough virus particles are delivered to the host, this process will become ineffective. "
]
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1skqsy | How did the institution of exiling criminals to siberia change from the Romanovs to the Soviet Union? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1skqsy/how_did_the_institution_of_exiling_criminals_to/ | {
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"Firstly, it is important to note that prisons in Siberia weren't that bad under the Romanovs. Lenin himself was exiled there, and this is where a lot of the sources focus, so I will discuss it more. His experience in Siberia was hardly that of a prisoner - he was permitted to make his own way there, the journey took 11 weeks, for much of which he was accompanied by his mother and sisters. Considered a minor threat, Vladimir was exiled to Shushenskoye in the Minusinsky District, a settlement that Vladimir described as \"not a bad place\". Renting a room in a peasant's hut, he remained under police surveillance, but was able to meet with other radicals (see below). His girlfriend was also arrested in 1898, and was allowed to move to the same town on the proviso that they were wed. He was allowed to do [intellectual work](_URL_2_)(1), gave legal advice to the locals gratis and the government gave him a gun to go hunting. [He was also able to visit other radicals in exile.](_URL_4_) [Here's a picture](_URL_0_) of where he stayed. This ‘luxury’ of course was due to Lenin's wealth, other exiles had a different experience.\n\nThe Tsarist government made use of a large network of prison camps and areas of exile on the verges of its empire to deal with dissidents and criminals and by 1897 there were 300,000 Russians in these prison camps. Life for the non-rich (say what you like about Lenin, he was certainly rich) was obviously harder and common criminals were sent to labour camps. “Some prisoners helped to build the Trans-Siberian Railway. Others worked in the silver and lead mines of the Nertchinsk district, the saltworks of Usolie and the gold mines of Kara. Conditions were vicious - those convicts who did not work hard enough were flogged to death. Other punishments included being chained up in an underground black hole and having a 48 pound beam of wood attached to a prisoner's chains for several years. Once a sentence had been completed, convicts had their chains removed. However, they were forced to continue living and working in Siberia.” From George Kennan (uncle of the American statesman), the author of Siberia and the Exile System (1891) - writing from the time. \n\nKennan’s work is problematic, largely due to his tendency to mudsling in what seems like a fit of proto-Cold War polemics. There are hundreds of Russian sources on the system of exile, but a lack of English ones - the major reason for this neglect seems to have been the limitations the Cold War placed on archival access. However, Siberian archives hold far more sources on exile than the Central state archives, and this could be restricting historians (travelling to Siberia is a lot more difficult than to the Russian capitals). As such, I'm probably not as qualified as any Russian historians who may answer.\n\nIt's important also to understand there was a differing reason for exile under the Tsars as well. While it did allow them to be rid of dissidents, it was also a way of populating the sparsely populated Far-East, at a time when Russia was trying to expand eastwards. Soviet expansion tended to be focused around the industrial cities, Magnitogorsk and the like, and there was a clear distinction between these and the Gulags. Instead prisoners were mostly used as free labour (In the Soviet system). From Kennan’s book: \"When criminals had been thus knuted, bastinadoed, branded, or crippled by amputation, Siberian exile was resorted to as a quick and easy method of getting them out of the way; and in this attempt to rid society of criminals who were both morally and physically useless, Siberian exile had its origin. The amelioration, however, of the Russian criminal code, which began in the latter part of the seventeenth century, and the progressive development of Siberia itself gradually brought about a change in the view taken of Siberian exile. Instead of regarding it, as before, as a means of getting rid of disabled criminals, the Government began to look upon it as a means of populating and developing a new and promising part of its Asiatic territory.\"\n\nThis basically argues that the Tsarist government began to view sending criminals to Siberia as both punishment and as a way to redistribute the population, as part of Russia’s eastward expansion, and this does seem to follow, with the construction of the Trans-Siberian railway, so I am wont to agree with Kennan here. \n\nSiberia was used during WW1 and the Civil War as a place for prisoners as well - [this source](_URL_3_) refers to “German and Austrian prisoners running loose over the countryside.\"\n\nAs for the system of imprisonment in the Soviet Union, and how it changed from Tsarist prisons, I could write a whole essay, but this is already a pretty long work. I’m trying to interpret if you’re asking “Why did it change?” or “What were the differences?” so before I ramble on about Gulags and so forth, would you mind clarifying that for me?\n\n\n\n\n\n(1)In 1897, Lenin was exiled to Siberia and in 1899 published the book The Development of Capitalism in Russia. That work was one of 30 theoretical works Ulyanov wrote while in exile.\n\nSources: Rice, Christopher (1990). Lenin: Portrait of a Professional Revolutionary. London: Cassell.\n\n_URL_5_ - This covers Kennan’s arguments in Siberian and the Exile System, if you want the book it’s [here](_URL_1_)\n"
]
} | [] | [] | [
[
"http://stalinsmoustache.wordpress.com/2011/01/26/lenin-in-siberia/",
"https://archive.org/details/siberiaexilesyst02kenniala",
"http://www.thedailybell.com/definitions/params/id/2818/",
"http://31stinfantry.org/Documents/Chapter%202.pdf",
"https://www.marxists.org/archive/lenin/works/lifework/worklife/1897.htm",
"http://www.spartacus.schoolnet.co.uk/RUSsiberia.htm"
]
] |
||
5z5lmy | How complicit were Colt Firearms and the US military in the disastrous introduction of the M16 rifle during the Vietnam war? | I recently read C.J.Chiver's history of the AK-47 (The Gun) which includes a chapter on the M16 rifle's introduction during the Vietnam war (excerpt [here](_URL_0_)). Chiver's account is a compelling read, aided by having clear villains and heroes. To what degree is this narrative accepted? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/5z5lmy/how_complicit_were_colt_firearms_and_the_us/ | {
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"I'm very much interested in hearing a separate evaluation of Chivers's argument in general. He is obviously fiercely critical of to initial rollout and introduction of the M16, but how valid are those criticisms?",
"I think chiver's book is mostly pop history.\n\n > In 1964, the Army was informed that DuPont could not mass-produce the IMR 4475 stick powder to the specifications demanded by the M16. Therefore, Olin Mathieson Company provided a high-performance ball propellant. While the Olin WC 846 powder achieved the desired 3,300 ft (1,000 m) per second muzzle velocity, it produced much more fouling, that quickly jammed the M16s action (unless the rifle was cleaned well and often).\n\n_URL_0_\n\n > In 1970, the new WC 844 powder was introduced to reduce fouling.\n\n > In October 1967, the Ichord Subcommittee released its 51-page report on the M16's troubles in Vietnam. The Army and Department of Defense (DOD) were faulted on a total of 31 points. The switch-over from IMR to Ball powder was the focus for much of the criticism.\n\n > \"The change from IMR extruded powder to ball propellant in 1964...was not justified or supported by test data.\"\n\n > \"...the sole-source position enjoyed by Olin Mathiseon on ball propellants for many years and their close relationship with the Army may have influenced the decision-makers.\"\n\n > \"The failure on the part of (Army) officials... to correct the deficiencies of the 5.56mm ammunition bordered on criminal negligence.\"\n\n_URL_1_\n\n > The tide began to shift toward Ball powders in the '50s; indeed, in April 1954, the Chief of Ordnance wanted every small arms cartridge to be loaded with it. Declared \"the greatest development in the field of explosives in nearly 100 years\" by W.H.B. Smith\n\nBall powder is faster, it's more efficient to make, it stores better and longer.\n\nWhat would take two weeks (originally it took 6 months) with non-ball powder can take 2 days with ball powder.\n\nBall powder is safer to make.\n\nMaking ammunition with ball powder is easier and cheaper.\n\nArmaLite developed 5.56mm nato with \"IMR 4198, IMR 3031, and an unnamed Olin Ball propellant\"\n\nWhen the frankford arsenal started manufacturing 5.56mm nato they initially made it with IMR 4475, the same powder used manufacturing 7.62mm nato ammo, but they found that 4475 5.56mm nato didn't reliably reach the 3,250fps needed to meet the helmet penetration requirements.\n\nThe military held fast on the 3,250 requirement, but also wouldn't accept an increase in chamber pressure. Remington, winchester, and federal refused to bid to manufacture ammo to those specs.\n\nThe pressure requirement was 52,000 psi, the manufacturers wanted 53,000 or 54,000.\n\nIn late 1963, remington asked for permission to change from IMR 4475 to Olin WC846 and got it.\n\nThe military needed 149 million rounds, and IMR 4475.\n\nThe alternatives were WC846 and the rod dupont CR 8136, they used WC846 which caused an increase in the cyclic rate (rate of fire), but the Air Force simply changed the cyclic rate spec to fit, and the army signed a series of waivers. Remington was owned by dupont, and chose CR 8136. When the army started receiving lots with CR 8136 they stopped issuing waivers allowing WC846 powder. Unfortunately, CR8136, like 4475 fluctuated too much from lot to lot.\n\nAcceptance testing, though, was completed with CR8136 ammunition.\n\nProduction switched to dupont ex 8208-4.\n\nBetween '65 and '66 5.56mm nato was delivered to troops in vietnam at a 9:1 ratio with CR 8136 in the minority and WC846 in the majority\n\nColt's analysis of the WC846 pressure was that, if anything, it would improve rifle performance.\n\nThe fouling problem with WC846 was with the calcium carbonate content, an additive that reduces the acidity of the ammunition, and different lots would have different amounts."
]
} | [] | [
"http://www.esquire.com/news-politics/a25677/ak-47-history-1110/"
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"https://en.wikipedia.org/wiki/M16_rifle#Adoption",
"http://web.archive.org/web/20160101074134/http://www.thegunzone.com/556prop.html"
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2nm49l | if somebody shot a gun directly at you, how far away from the shooter would you have to be to realistically jump out of the way of the bullet in time? | I realize it also depends on the kind of gun. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2nm49l/eli5_if_somebody_shot_a_gun_directly_at_you_how/ | {
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"When I was in the army, we were taught to count a second for every three hundred metres (meters, for the american audience), when estimating how far away a shooter is. If you knew exactly when the shot was fired, you'd probably need about 600m to get out the way.\n\nYour problem is that you've no reliable way of knowing when the shot is fired, as with most rifle rounds, the sound of the gun will arrive after the bullet does.",
"Mythbusters did this. Because most bullets travel faster than the speed of sound, you would be hit before you knew the gun was even fired. No dodging possible.\n\n_URL_0_",
"A German TV show tested it but there is no translation: _URL_0_\n\nIn the end I think the result was about 2 seconds on 1000meter / 0.625mile with a sniper rifle.\n\nAs mentioned by /u/glyttch it depends on many factors for example speed of your projectile, reaction time, ...",
"You cant. That's why we have guns and not bows and arrows any more :)",
"There are just too many variables with this. It depends on what you're shooting the gun with. Is it a cannon, a bow, slingshot, or another gun? They all affect how fast the gun can travel. Also what kind of gun is it? A pistol and machine gun travel through the air differently.",
"The type of ammunition is actually one of the most important things. A 22 short is a very slow round as are certain shotgun loads. These travel well below the speed of sound. If I recall 22 shorts travel at something like 500 fps where the speed of sound is around 1100 fps. Nobody is going to be shooting at you with 22 shorts though. What is possible is someone shooting at you with subsonic ammunition. Most rounds have a subsonic variant, the use of these rounds varies but a common role for these subsonic rounds is in the application of a suppressor. This combination can make some rifles almost silent and impossible to see the muzzle flash from. \n\nTechnically you can easily move out of the way of a bullet if shot from 300 yards with subsonic ammo. Problem is you would never know when the shot was fired, even if you had a magnified line of sight on the shooter. The bullet would reach you at almost the same instance as the sound. This is a best case scenario. \n\nThe only scenario i can think of that would actually allow you to dodge a Bullet is if you were being shot at by some artillery. Due to the massive blast of an artillery piece you could see the artillery fire a mile or so away and then book it away from where you were. This of course is not how modern artillery works. Artillery is almost always hidden behind something and firing beyond the line of sight. \n\nSo no, you will pretty much never be able to dodge a bullet . ",
"Great question! It depends on the speed of the bullet, which is affected mainly by the casing, but also by the style of bullet (hollowpoint vs. FMJ, percent lead makeup, etc), the type and amount of powder used in the load, the type of rifling in the barrel of the gun, the barrel length, not to mention atmospheric conditions (physics is hard!). For general purposes, a \"slow\" bullet would be a .45 ACP, which actually travels just under the speed of sound. A \"fast\" bullet would be something in a magnum rifle class, such as a 300 Win Mag round, which travels around 3,000 feet per second. There are specialty rifle rounds which travel upwards of 5,000 or 6,000 feet per second, but we're not going there because we want to talk about dodging the bullet! \n \nThe best case scenario is obviously a slower round, such as a .45 ACP could theoretically be dodged not only by having the proper magnification to see the trigger being pulled (muzzle flash or with a scope), but also by hearing the bullet and then dodging. Assuming a light .45 ACP load which causes the bullet to fire at 800 f/s or about 550 mph, the absolute time to dodge with visual warning would be 6.5 seconds at one mile. As sound travels that distance in just over 4.5 seconds, almost a full 2 seconds would be available to a person to dodge the bullet with auditory warning alone. The .45 round would need some serious tilt to travel this distance, and it would be ridiculous to try and shoot someone like this. More likely, one would be firing a round that travels at 3000 f/s out of something like a 300 win mag, which travels much faster than sound, but at one mile gives you a second and a half to dodge with the benefit of visual forewarning. \n \nEDIT: I'm assuming the time of light travel to be 0, as it is negligible with these small distances.",
"A .45 is a \"slow\" bullet, relative to most other rounds. It's so slow that it is -almost- perceptible as it goes down the range. Almost in the sense that your eye can detect something, some sort of movement, but even then, you can't truly see anything more than a sliver of a steak. So no, I don't think you could dodge a bullet, not in the sense that you could see the bullet and dodge, as opposed to seeing the gun and reacting to the idea that someone was getting ready to fire it. ",
"Assuming you're fighting at dusk or night and the enemy is using tracers, you could feasibly dodge fire around 800m. Bullets only travel so fast, and if you've ever seen night-fire exercises or, more rare, dusk combat footage, you can see just how slow they really are at these ranges. \n\n\"Jump\" is a very specific way to dodge fire anyway; maybe you only need to stick your head back down or roll over.",
"Mythbusters did this. Under controlled circumstances 500m (provided you know the instant the bullet leaves the barrel). Under \"normal\" conditions you cant see the muzzleflash over 200m distance and the bullet travels 3 times the speed of sound....\n\nFYI They used a sniper rifle in the 30cal range since less powerfull weapons would not reliably hit the target at that distance.",
"You would have about 1 second time to move if a bullet was fired out of the barrel of a gun roughly 950 feet away. A .45 caliber round depending on brand travels around 900-1000 feet per second.",
"Let's assume for a second that you know, instantly, that the bullet is about to be fired. Ignore, for the moment, all the problems with this assumption. \n\nA bullet moves about approximately 770 MPH, which is about seven times faster than a hockey puck shot by an NHL player at its fastest. Many NHL goalies (among the quickest reflexes of any athlete) can flash out a part of their body and meaningfully move their position enough to make the save when a puck is shot at this distance from between 5m and 10m away. \n\nExtrapolating, we could say that somebody with extremely quick reflexes could, in theory, get out of the way of a moving bullet if it's fired from between 35m and 70m. This would include the time required to process the shot being taken, provided you were expecting it (as NHL goalies expect the opposition to shoot but try not to react until after the shot is taken). \n\nUnfortunately, for this to be useful, you would have to be carefully watching the shooter and know, based on his finger position, when the trigger has been pulled. You aren't going to hear the shot in time and you are unlikely to see the flash. If you wait until you see the recoil, you have given up valuable reaction time. The further away, the harder it is to see the finger move. \n\nIt's more or less absurd, therefore, to think that you can dodge a bullet from any distance if you wait until the shot is fired to react, even if a professional athlete can move quickly enough to get out of the bullet's way if it is fired from the other side of a football field, assuming no delay in warning. "
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cffyeh | where and how do mountains, rivers, forests, and deserts form? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/cffyeh/eli5_where_and_how_do_mountains_rivers_forests/ | {
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"Generally speaking mountains form in one of two ways.\n\nThe primary way is due to plate tectonics. The surface of the Earth, the continents and sea floor are broken up into a series of plates which sit on top of the mantle which is made up of liquid molten rock. As a result the plates are in constant but very slow motion. When the plates suddenly jerk and move we get an earthquake.\n\nWhere the thicker and tougher continental plates meet the thinner and weaker oceanic crust, the plates heave over each other. The Oceanic plates subduct (go underneath) the continental plates which causes the continental plates to be forced up creating mountains.\n\nThe second way to make a mountain is through volcanism. Hot molten rock finds a way to punch through the crust of the earth spewing onto the surface creating a volcano. Over time this volcano erupts numerous times, causing molten rock to pile up to form a volcanic mountain. These are most prominent in the ocean because the oceanic crust is thinner and weaker.\n\nMountains and the continents themselves are what cause forest, deserts, and rivers to form.\n\nIce forms at high altitudes from rain falling on mountains. This melts creating the sources of rivers. Rivers will then flow downhill and across the ground until they reach an open body of water like the ocean. Rivers are also fed by smaller streams form fromed rain water collecting over a large surface area.\n\nDeserts often form due to mountains. Moist air from the ocean travels over land, but when it reaches mountains it is forced up. This causes the rain water to fall on the mountains, so by the time this wind reaches past the mountains it is hot and has no moisture left. In time this forms a desert.\n\nBut mountains can also cause create an area rich in moisture due to the rivers they spawn, which can form a rain forest like the Amazon."
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6jturp | Why is Strychnine referenced so often in popular culture in reference to poison? Was Strychnine a commonly used murder weapon? | There's the legend that Robert Johnson died from drinking wine from a bottle spiked with Strychnine. No one really knows what happened so why Strychnine?
In *Office Space*, Milton threatens to put "Strychnine in the guacamole." Though a colorless, tastless poison it may be, there must other similar toxins that could be used in its place.
A third example that comes to mind is Tom Lehrer feeding Strychnine to pigeons while "Poisoning Pigeons in the Park."
Why is Strychnine so commonly referenced? Besides being colorless and odorless, are there other reasons?
| AskHistorians | https://www.reddit.com/r/AskHistorians/comments/6jturp/why_is_strychnine_referenced_so_often_in_popular/ | {
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"Strychnine has long been used as a rat poison (or other mammal/bird pest poison). During the 19th century production increased dramatically and it became practically a household item. Pest control has always been a major concern and in the early industrial age it was something many people took into their own hands.\n\nStrychnine is an alkaloid so it has a quite bitter taste, which is an evolutionarily derived signal to avoid it. However, humans have acquired the habit of ingesting alkaloids such as caffeine (and theobromine in chocolate), quinine (a malaria treatment), nicotine, cocaine, and others, so we've overriden the natural instinct to avoid bitter flavors. This has made it possible for people to imbibe a lethal dose of strychnine without necessarily being immediately aware that they are doomed, and a lethal dose might be just a fraction of a gram. Indeed, there's the case of writer Henry Randolph who in 1892 mistook strychnine for quinine when mixing his tonic and accidentally killed himself.\n\nGiven strychnine's wide availability and the ease with which it could be used to kill someone it became used as a poison and, more so, became famous in literary tales in that role. Strychnine kills by causing convulsions which result in asphyxiation. One of the reasons it was a popular poison in the literature is because it's generally fairly obvious as a poison after the fact, leading to the classic scenario of a victim dying by poison with many potential suspects. As such things tend to do one generation of fictionalized portrayals of the use of strychnine as a poison gave rise to the next, and so forth. It developed into shorthand for \"poison\", everybody knew about it either from other media or from first hand knowledge of its use in pest control."
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6ofrt5 | what happens to the newly "dead" bacteria on your hands after you use hand sanitizer that "kills" bacteria? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6ofrt5/eli5_what_happens_to_the_newly_dead_bacteria_on/ | {
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"They are still there just dead. This reason is why antibacterial soap doesn't work as well as it sounds it should. Washing your hands actually removes bacteria from your hands, it may not kill it but it is a very effective method of sanitation for that reason. ",
"Like another poster has said, you can't really wash off the dead bacteria because water acts differently on them due to their size. \n\nAlso when you use antibacterials, the area will quickly become repopulated with bacteria from your environment, other parts of your skin and by the bacteria that wasn't killed multiplying. \n\nAs the area becomes repopulated, the new bacteria will use the dead bacteria as a food source. In essence, the dead bacteria becomes food for the still living bacteria. \n\nEdit: words - silly phone predictive text. ",
" > I'd prefer not to have bacteria corpses on my hands, thanks.\n\nThe irony here is that the human body contains just as much bacteria as our own cells. Not only that, but we are desperately dependent upon the bacteria that lives on our skin to protect us from all sorts of nastiness.",
"So basically using germ-x is a waste of time and it's better to wash your hands?",
"[Excellent answer from a few months back.](_URL_0_)",
"The super bacteria feed on the corpses of its weaker brethren. It makes them stronger. We are only feeding the itty bitty beasts",
"Hand sanitizer kills bacteria by lysing cell membranes. You are quite literally cutting them open and spilling their juice all over you. By rubbing your hands together there is mechanical removal of bacteria, to some extent, but your best bet is to wash under water with soap. The soap will help lyse the cell, and allow the bacterial remnants to become suspended in water. Then, they should slide off, as running water does. ",
"Objects can be made \"bacteria-corpse\" free with depyrogenation using gamma irradiation. Pyrogens are bacteria fragments left over after cell death.\n\nYou cannot be depyrogenated, because you have bacteria that live with you all the time. They eat the dead ones when they find them, and they keep your outsides happy and healthy. If you lost them, you would end up with all kinds of horrible side effects because your microbiome (or personal bacteria ecosystem) is just as much a part of you as your own cells are.",
"don't worry, the dead bacteria will be very quickly eaten by the bacteria that survived, bringing forth a mini revolution of stronger hardier bacteria.\n\nYes, you read that right. Hand sanitizers are bad for you and the world we live on.\n\nNever use hand sanitizers unless you've just touched something you are pretty sure had something contagious on it, or if you yourself have a contagious bacterial (viruses won't care about alcohol) illness and are about to cook for someone. In those cases, having less bacteria on your hand for a brief period is actually beneficial.\n\nBest way to stay healthily clean? soap. It'll get rid of the brunt of the gunk mechanically, not leave any corpses behind, and most importantly not give preferential treatment to the worst bacteria.",
"I'm sure someone else has already said it, but you're covered in and surrounded by dead bacteria all the time. Don't worry, you're used to it.",
"So i had to remove the top reply in this thread. I know people are going to want to know why, and my explanation is buried there.\n\nIt was a copy and paste of [this comment by /u/TheTimeNotTheMiles](_URL_0_). That is one of the reasons that the OP of the removed comment didn't respond to anyone.\n\nThat violates our [rule #3](_URL_1_) explicitly. I think though that it violates the spirit of rule #1 as well. \n\n\n---\nI'll post the contents of that original comment here for convenience.\n\n > So lets say we have a scalpel, right? Simplest medical device there is. There's a number of ways to make it totally(ish) sterile- gases, steam, dry heat, gamma radiation.\n\n > But as you ask- the little bacterial corpses are still there. Waiting, one presumes, for tiny necromancers.\n\n > The problem occurs when you stab someone with the scalpel, preferably in a medicinal way. The bodies immune system works by identifying certain chemical triggers in bacteria, and has no way to know that, for example, the lipopolysaccharide hanging around in someone's heart is not part of a bunch of living bacteria, but the floating corpses of dead bacteria.\n\n > The dead byproducts of bacteria are called \"pyrogens\" because they cause (among other things, such as death) fevers.\n\n > Where do they go? Nowhere. Bacteria are small enough that water has completely different properties on their level. Beyond rinsing off gross matter and reducing bacterial load, washing can't do much.\n\n > So for things like heart surgery scalpels, there will usually be a second step of \"Depyrogenation\" This is the process, not of killing bacteria, but of removing the bits left behind so they don't trigger an immune reaction. This varies widely in complexity depending on what you have to depyrogenate- steel scalpels are easier than an injectable drug, for example. Typically, the goal of the process is to so thoroughly break down the biological material left behind.\n\n > **Are my hands covered in bits of dead bacteria?**\n\n > No your hands aren't covered in dead bits of bacteria. They're covered in happy, healthy bacteria.\n\n > **Then why wash my hands??**\n\n > Washing your hands removes dirt and debris that carry the nastiest bacteria. Sterilizing your hands is a ridiculous notion however- your hands are made of cells, bacteria are made of cells. Anything that would kill them would kill your cells. Your hands, and literally everything else on the world not currently under direct gamma radiation bombardment, are covered in bacteria,\n\n > Quick run down on terms:\n\n > \"Cleaning\" a medical device is basically doing dishes-getting blood n bits off the reusable ones. (plz dont reuse single use medical devices that makes regulatory professionals sad 😭)\n\n > \"Disinfecting\" is using chemicals to get something purty darn clean.\n\n > \"Sterilization\" is killing all* the germs on something\n\n > \"Depyrogenate\" is taking bacterial corpses and reducing their remaining structure to a point where your immune system won't recognize it and freak out.\n\n > *SALx10-6 is the typical sterility level for a medical device. one in a million germs/one in a million devices\n\n---\n\nEdit: I'm going to unsticky this as i think this and my original removal reply are visible enough on their own by now.",
"This reminds me of a Harry Hill joke where he memed about not using mouthwash to avoid having a mouthful of dead germs.",
"What was the explanation? I clicked on this to see what the answer was. Can anyone repost the answer and properly cite the source? I am really curious. "
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1u0mbo | In the 1820's, how did people send messages between countries? | Ideally, what I'm curious about is how the Australian colonies might have sent letters (or similar) back to England, but any example from any country is perfectly fine. Did 'common' people do it?
I'm also curious if only literate people did this, or if it was common for people to transcribe a message and send it on somebody's behalf? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1u0mbo/in_the_1820s_how_did_people_send_messages_between/ | {
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"Hopefully someone can contribute more info/detail regarding long-distance communication during that period, but you can get started on this section of the FAQ - the posts in subsection \"ship-to-ship\" is the most relevant for the time-period you're interested in \n\n[Communications](_URL_0_)\n\n*see the popular questions link on the sidebar or the wiki tab above",
"Australia's first post office was officially born in 1809 in Sydney and was led by former convict [Issac Nichols](_URL_3_). He was put in charge of all mail arriving in New South Wales, as there quite a lot of mail theft from the incoming ships. He ran the post office out of his own home and townspeople would know they had letters waiting for them through messages in the Sydney Gazette. \n\nIn 1828, Australia's first postman began delivering mail around Sydney. The [overland mail routes](_URL_1_) also began in the late 1820s, sort of like the Australian version of the Pony Express which included regular horse and coach deliveries to towns just outside of Sydney. It wasn't until the 1830s when mail delivery started to move further from Sydney itself. The [discovery of gold in the 1850s](_URL_0_) also brought a huge amount of people to Australia, which meant mail delivery became even more important.\n\nShips would be the means of transportation for letters to and from places like Britain, although most people in 1820s Australia were either convicts or descendants of convicts whose education was limited. So the common person may have had a bit of trouble with reading and/or writing. However, post office's in the colonies would have had to have a postmaster who could read and write so he could transcribe their messages for them.\n\n[The Australia Post](_URL_2_) actually celebrated 200 years in 2009. Their website had a lot of interesting historical facts. I hope this helps!"
]
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4bxdcd | why do our eyes "burn" when they are red? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4bxdcd/eli5_why_do_our_eyes_burn_when_they_are_red/ | {
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"Red eyes usually mean there's a degree of inflamation going on. During inflamation, several chemicals are released and they cause blood vessels to become swollen and they become visible. Burning and Itching sensations are transmitted through unmyelinated nerve fibers that can be easily stimulated from those chemical I mentioned before."
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f4s221 | What were eating disorders like in colonial North America? | I’m thinking 13 colonies, but I’ll take a broader range of North American colonies. Was there an acknowledgement of eating disorders—not by name, obviously, but “oh Sally throws up after every meal”? If so, was there a class difference? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/f4s221/what_were_eating_disorders_like_in_colonial_north/ | {
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"To answer this question, we first have to take a moment to consider the nature of mental illness. Mental illness is not a 'static' thing the way that physical illness is - the prevalence and the expression of mental illness is hugely dependent on the culture and surroundings a person was raised in, and the mental illnesses that we are familiar with in modern western industrialized nations often look very different than mental illnesses in non-western societies, or in pre-industrial societies. A person with untreated diabetes in modern America is going to have the same symptoms as a person with untreated diabetes in modern China or in colonial America, but a person with a mental illness is going to potentially have very different symptoms in those different settings. \n\nOur culture and our surroundings shape who we are as people, our values and beliefs, our patterns of behaviour, and the bounds of what is 'acceptable' behaviour and what is not - when something goes wrong and we experience mental illness, it tends to happen in a way that makes sense within the greater context of our cultural surroundings. An American who experiences depression is likely to experience loss of motivation, feelings of sadness or numbness, and social withdrawal; these are symptoms that make \"sense\" to us culturally, and that we understand to signal depression. A Chinese person, on the other hand, is likely to experience depression as headaches, fatigue and insomnia; these symptoms are more accepted and make more sense within the bounds of this culture, and they tend to be much more prevalent among people who are experiencing what we would consider depression. \n\nIt is also possible for a mental illness to exist only within the bounds of one single culture, as a response to a pressure or stress that is unique to that culture - elderly Japanese women, for instance, experience a mental illness called 'One's Husband Being at Home Syndrome' that is common to them, but not found anywhere else in the world. The structure and power dynamics found in older Japanese couples - along with Japan's lack of social safety net - cause Japanese women to suddenly find themselves in a unique stressful situation when their husbands retire, leading to the development of a \"new\" mental illness that makes sense within their culture, but not anywhere outside of that particular place and population. Mental illness is flexible, and reflects the circumstances of a person's life. Eating disorders are particularly prone to cultural influence. Although they do exist all over the world, they are most prevalent in Western cultures that highly prioritize thinness as a cultural beauty standard, and we have actually watched rates of eating disorders rise as non-westerners are increasingly influenced by western cultures. We have also seen eating disorders rise in males recently, as beauty standards for men become increasingly rigid - eating disorders have a very strong tie to the culture they exist in, and are very responsive to changes in cultural ideals.\n\nSo when we think about what eating disorders - or any mental illness - was like in the past, it's important for us to consider that eating disorders may have looked very different hundreds of years ago, and that behaviours that resemble modern-day eating disorders may have had completely different origins and motivations. Since we cannot assess people who lived in Colonial America, we cannot formally diagnose them with eating disorders or assume that their unusual eating patterns were the equivalent of similar eating patterns we see today. We do have reports of behaviours in the past that outwardly resemble modern-day anorexia to some degree, but it's just not possible for us to conclusively say that we're looking at the exact same disorder - in the past, sudden and unexplained loss of appetite could have been the result of a disease, parasite or accidental poisoning. \"Sally throws up after she eats\" could mean anything from \"Sally is allergic to something in the food and we just don't understand that\" to \"Sally is coming down with dysentery\". \n\nWith that said, we do have historical evidence of pre-industrial people appearing to intentionally deprive themselves of food, to the point of physical harm or even death. These behaviours were often tied to religious fanaticism; early Christians prized self-sacrifice, suffering and the denial of earthly pleasures as signs of a person's purity and piousness, and many of the early accounts we have of people intentionally starving themselves to death come from people who were heavily engaged in this mindset. For people living in strict puritanical cultures, fasting was a sign of spiritual strength. \"Sally doesn't eat at mealtimes\" could be understood by the community and by Sally herself as \"Sally is fasting to be closer to the Lord\", even if there was an underlying psychopathology at play. Again though, it is not clear if this behaviour is an exact parallel for modern-day anorexia; people who deprive themselves of food to a dangerous extent for predominantly religious purposes do still exist today, and they are sometimes diagnosed with anorexia nervosa, but their stated motivations have more to do with spiritual purity than physical appearance."
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2pl6uv | how did they make glass 1,500 years ago? | Referring to the post on the front page about the discovered mummies:
_URL_0_
There were glass artifacts dug up, how did they manage to make them without modern tools and machines? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2pl6uv/eli5_how_did_they_make_glass_1500_years_ago/ | {
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"You just need a really hot kiln.\n\nIf you can make iron things you can make glass.\n\nGlass isnt hard to make."
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1o9f3o | Contemporary evidence shows that Vikings were of average (or close) height, while historical sources assert that they were veritable giants. How do we reconcile this? | Thanks to paulthepenguin for pointing out this clarification: average for their time (sources differ, but something like 5'6" or 5'7" compared to a contemporary average of 5'5"). | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1o9f3o/contemporary_evidence_shows_that_vikings_were_of/ | {
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"Average compared to whom? If you're referring to average compared to modern-day height, than historically they would have appeared to be quite large.\n\nIt may also have been hyperbole on the account of historians; the Vikings were ferocious, as I recall, so may have simple been viewed as \"giants\" because of their fighting, rather than literal giants.\n\nThis is only conjecture on my part though, as I'm not well-versed in this aspect of history!"
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1mhxp0 | [Physics] What happens to the kinetic energy in a car involved in a crash? | If a 1300kg car is travelling at 100km/h and the brakes were applied until it stopped, its kinetic energy would been directly turned into heat in the braking system (mainly in the discs and pads). If the same car hit a solid wall at the same speed, obviously the energy dissipates through the car as it crumples, but what happens to it then? Is it still turned into heat and if so, is a freshly crashed car going to noticeably hotter (fuel explosions aside)? | askscience | http://www.reddit.com/r/askscience/comments/1mhxp0/physics_what_happens_to_the_kinetic_energy_in_a/ | {
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"A crashed car will indeed be hotter, though I'm afraid I couldn't put a number on it. If you take a small bendable piece of metal like a paperclip and bend it back and forth quickly, you can make it quite hot to the touch; bending metal causes internal friction which releases heat.",
"It will be converted into other forms of energy. Yes, one of those is heat, but one thing the other answers haven't mentioned is things like noise, or vibrations, or changes of state - eg the rubber from tyres may be slightly sublimated during breaking. Think about the sound a car crash makes - it's a considerable amount of vibration.",
"Some of the energy turns into vibrational energy (heat is the increase in vibrational energy), but there is also energy that goes into deforming both the car and the wall, which will also dissipate eventually into vibrational energy."
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3dqy45 | We all know a lot venomous or poisonous animals mostly have bright colors to warn predators. Are there any animals that abuse this fact? | i.e. like an animal with bright colors that actually isn't poisonous at all, but just trying to look like it. | askscience | http://www.reddit.com/r/askscience/comments/3dqy45/we_all_know_a_lot_venomous_or_poisonous_animals/ | {
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"Sure, apparently this is called [Batesian mimicry](_URL_0_)."
]
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"https://en.wikipedia.org/wiki/Batesian_mimicry"
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3l0lrt | how can a color blind person correctly name previously unseen colors when wearing enchroma glasses? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3l0lrt/eli5_how_can_a_color_blind_person_correctly_name/ | {
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"My guess is that they already know what color the object they're looking at is, but can't see it correctly.",
"Just a guess but I would assume they have been told their whole lives what objects are purple and they see different shades of colors for purple. So when the put on the glasses, prior to, they know it's the \"purple\" they see prior to putting them on. So after the glasses are on, they see the new color as normal vision would see it but know what the color is already.\n\nHopefully that helps.",
"Colorblindness isn't black and white.\nIt's not \"I don't see purple\"\nIt's a shades thing, some Greens look more red, some purples look more blue.\n\nThe enchroma seperates the wavelengths of light that is close together. It doesn't make purple appear, it makes the red more distinct / separate from the blue light.\nThis makes the purple more vibrant. What was a dull, mostly blue color is now a vibrant purple.\n\nWe know what the colors are, these glasses just help in making them \"better\" and stand out",
"By the time you're an adult, you'll know that grass is green, whether or not you can see it. It's just one of those bits of knowledge that everyone at some point will be told. \n\nIf you put glasses on and can now see that grass is a colour you've never previously been able to see, that won't stop you knowing that colour is green. ",
"It's just a matter of mapping some visual input to a label.\n\nI see largely in continuous grey, lacking cone receptors in my eyes. I learned to map what I see (the ocean or grass) to certain labels (blue or green). Colors that were not widely used when I was growing up (and learning \"colors\") are total mysteries to me. So, for example, I struggle with teal when it's presented to me."
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63es0h | why does zalgo text seem to display everywhere regardless of localization? | I'm talking about t̠͚̺̝̠̤̟h̜͙̤i͏s̵ ̞͇̝k̛̗͉i̭͕͓̻̲ņd͍̼ ͍̮o̙̯̬͔͍̗̝͜f̘͕̠͕͕͓ ͙̘̠̖̞̠b̘͝i͕̲z
I understand that they're combinations of "stacked" characters. What I don't understand is that it seems to break localization restrictions. Take a phone messaging service - why are the combined characters able to go beyond the speech bubble, above and below? Is it simply because no one actively prevents it? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/63es0h/eli5_why_does_zalgo_text_seem_to_display/ | {
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"Zalgo text takes advantage of tricks built into unicode. \n\nUnicode is a standard for how text in all the world's major languages should be handled. It includes support not just for the latin alphabet but quite a few writing systems, including ones where text goes in other directions than left-to-right. On modern computers and technology, supporting unicode is pretty much required if you want your device to be usable globally.\n\nUnicode has some characters built into it that aren't \"real\" letters, but indicate \"this next symbol goes above/below the previous one\" or \"this next stretch of text is vertical, not horizontal.\" It's intended for languages where that happens... but if you cram a bunch of those characters together you can get weird effects like the zalgo text.\n\nBecause unicode just changes how characters are arranged, it can't really be used for glitches or code exploits, so nobody loses sleep over \"if I try really hard I can make this messaging app look weird.\""
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2lth0s | How come my urine color isn't affected by drinking colored drinks? | Are the colorants present in drinks consumed, eliminated in other ways or are they building up inside the body?
(The specific drink i'm referring to is Coca-Cola but it might not be relevant) | askscience | http://www.reddit.com/r/askscience/comments/2lth0s/how_come_my_urine_color_isnt_affected_by_drinking/ | {
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"Largely food additives which are used for colouring follow one of three paths; they are either digested in your gut (broken down in to constituent bits which can be absorbed as food), absorbed as-is and later broken down by the liver, or they pass straight through unaffected (either not being absorbed by the gut at all or once in the blood stream being filtered out by the kidneys).\n\nSo, no they are not 'building up inside' you.\n\nWith regards coca-cola, this is principally colored with \"Caramel Color\" a golden to brown food colouring additive. This colouring is made by acid oxidising simple sugars, this gives them a dark, burnt appearance and flavour. They can then be added to food in small amounts to make them brown. The long and the short of it is that you simply digest the colouring as you would other sugars.\n\nAt the other end of the spectrum are the yellow to red Betalains pigments present in beetroot and other vegetables. These are only minorly absorbable in your gut and they mostly pass through totally unchanged and will make your stools quite red. Occasionally you can/do absorb significant amount of betalains in the gut but this is filtered out by your kidneys giving you pink urine (Beeturia)."
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15qr17 | Why didn't Russians eliminate the Feudal system even though they observed the rest of Europe go through the Renaissance because of the Feudal Systems end? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/15qr17/why_didnt_russians_eliminate_the_feudal_system/ | {
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"Russia ignored western Europe until the rule of Peter the Great (1682-1725)."
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1dsp3t | What were some of the great duels and rivalries between historians? | Reading 1491 by Charles Mann, it is obvious that historians and archeologists are extremely passionate and things can go south very fast. High-Counters vs Low-Counters, Clovis vs pre-Clovis, it gets pretty ugly.
Considering Wittegenstein and Popper nearly came to blows (or pokers), what are some of the great historian rivalries, both current and settled? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1dsp3t/what_were_some_of_the_great_duels_and_rivalries/ | {
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"I'll be a jerk and not give names, since I can't remember them, but a buddy and me wrote a treatment for a film about dueling paleontologists during the heyday of bone hunting. these guys would reconfigure the other guy's skeletons into different animals, and once even hopped onto a moving train in order to steal a new find. There were shades of Indiana Jones in these guys.\n\nNot true historians, but close.",
"Even though not exactly a duel, the [Historikerstreit](_URL_0_) (\"historians' dispute\") was a major controversy in German historiography concerning the singularity of the Holocaust.\n\nBasically, historian Ernst Nolte held two speeches (one in 1980, one in 1986) in which he argued that Hitler had good reasons to treat the Jewish people as \"prisoners of war\" and in which he explains the \"asiatic deed\" (i.e. the crimes) of the Nazis as a reaction to the Russian treatment of the Germans:\n\n > \"War nicht der ‚Archipel Gulag‘ ursprünglicher als Auschwitz? War nicht der ‚Klassenmord‘ der Bolschewiki das logische und faktische Prius des ‚Rassenmords‘ der Nationalsozialisten?\"\n\n\n > \"Wasn't \"The Gulag Archipelago\" primordial to Auschwitz? Wasn't the \"class murder\" of the Bolsheviks that logical and factual prius of the National Socialist \"race murder\"?\"\n\nThese and other theses provoked the reaction of philosopher Jürgen Habermas, who answered with a now famous article titled *Eine Art Schadensabwicklung*, in which he attacked Nolte and other historians (namely M. Stürmer, A. Hillgruber and K. Hildebrandt) for their \"apologetic tendencies\" regarding the crimes of National Socialism and especially the singularity of the Holocaust.\n\nA *huge* debate ensued involving numerous historians, journalists, and philosophers and which is still talked about today from time to time (even in mainstream newspapers and journals). Topics were the German *Sonderweg* (separate historical path), the uniqueness of the NS crimes, the comparability of genocides and the nature of the National Socialist crimes in general.\n\nThe collection of the original articles can be found in:\n\n- Augstein et. al.: *Forever in the Shadow of Hitler? Original Documents of the Historikerstreit, the controversy concerning the singularity of the Holocaust*.\n\nSorry for the broken English.\n\n\n",
"On the Strict academic level, Hayden White has a long standing Quarrel against Carlo Ginzburg. One, defending the prevalence of Narrative in the creation of historical discourse, meaning Alterity can not be reached versus a heavily Documentalist, source based approach that says the past as it was is accessible to present people via diligent study of Sources. \n\n\nThey are at this for quite some time, one writing articles against the other, but never really considering each other's ideas. The Theory of history has been on an Aporia, Stalemate for quite some time. Jörn Rüsen has tried to make a bridge between the two, but so far his viewpoint has not been turned into standart.",
"Only time for a quick note before bed on this, but you may be interested in the career of the English military historian Basil Liddell Hart. A remarkably popular figure in his day, and still amazingly influential and widely published even now, his strategic theory of the \"indirect approach\" as taken by many as a ground-breaking reappraisal of the causes and conduct of the infantry stalemate of the First World War. His ideas were widely admired, and seem to have some impact on the thinking of certain German generals in the inter-war period.\n\nWhere he figures as an answer to your question, however, is that Liddell Hart could with some justice be said to have become the *de facto* \"pope\" of First World War historiography from the 1930s until his death in 1970. It was very hard for other historians in England -- particularly younger ones still making their names -- to get their manuscripts published without them first having been examined by Liddell Hart and given his imprimatur. The consequences of this were sometimes quite arduous: Liddell Hart's ideas about the \"proper\" interpretation of the war and its conduct were idiosyncratic, even if widely hailed, and he did not respond well to those who offered alternate views. On several occasions he is known to have instructed friends of his to produce \"independent\" \"reviews\" of books to which he objected -- using his carefully prepared notes -- to be published in a variety of periodicals with the aim of consequently creating a \"consensus\" that the book was a failure and should not be taken seriously. The eminent historian John Terraine was one victim of such treatment, though he'd have the last laugh (of a sort) in the end.\n\nIndeed, it was the involvement of the likes of Terraine and Correlli Barnett in the production of the unprecedented 26-episode BBC documentary series *The Great War* (1963-64) that saw Liddell Hart resign from his position with the production and announce as much in a scathing public letter. His objections were varied, but some centered around the series' treatments of Sir Douglas Haig as a person and the Somme Offensive as a campaign; Liddell Hart, like many of the establishment historians of the time (like A.J.P. Taylor), firmly believed the former to be an incompetent monster and the latter to be an irredeemable catastrophe, so a counter-example urging greater nuance did not please him much.\n\nStill, this nuance really has won out in the field of military studies, if not yet entirely in that of cultural memory. The next generation of military historians -- among them Terraine, Barnett, Brian Bond, Richard Holmes, Gary Sheffield, Dan Todman and William Philpott -- have been more cautious in their historiography and less willing to start from a position of naked outraged and then work their way up. We can see a sort of last gasp of the other school in 1988 and 1991, with Denis Winter's *Haig: A Reassessment* (it wasn't) and John Laffin's *British Butchers and Bunglers of the First World War* (the title alone...), but the views of the historians listed just above are beginning to take the field. Neither book now commands much attention, and some of the claims of the first have been quite thoroughly assailed.\n\nUnfortunately, the position of the \"Lions Led By Donkeys\" myth so industriously propagated by Liddell Hart is quite firmly entrenched in the popular memory, and with the centenaries fast approaching the military historians are going to have their work cut out for them. We'll see.",
"The History Wars of Australia are ongoing _URL_0_ particularly Windshuttle vs Reynolds."
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733jpf | why do (most) americans reject cars with a manual shift stick? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/733jpf/eli5_why_do_most_americans_reject_cars_with_a/ | {
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"1. Automatic transmissions are price-competitive here (and in many models the auto is actually cheaper).\n2. Gas prices in the US have historically been very low by European standards. So the gas-saving nature of a manual wasn't as big a selling point in the US.\n3. We drive big cars on busy roads, and we drive them *a lot*. Commuting 3+ hours a day is not unusual in America. That much time on a stick shift in traffic is no fun at all.",
"There used to be good reasons to drive a manual shift car (regarding getting good gas mileage), but that's really not an issue these days. The margin is so small that people would rather not have to deal with it.\n\nSo if you are given a choice of manual or automatic, it becomes \"why not automatic?\" And the only legit answer to that question is price (it adds about $1500 to the price on most cars).\n\nMost automatic cars made in the last 10 years can also still manually shift, without the use of a clutch.",
"Automatic transmissions are what most people here learned on and they won't know how to drive stick. These days, advanced auto trans with 7+ gears tend to be more fuel efficient than manuals, and many cars don't even come with a manual option due to slower sales.\n\nAutomatics began taking over simply because of the nature of stop and go traffic - people drive everywhere, cities in the US are far more spread out than cities in other parts of the world, and manual transmissions are a hassle when you treat your car like an appliance that gets you from A to B. I own a manual car myself but I take my automatic into san francisco in the (rare) times I have to drive in there, because manuals in stop and go traffic suck and any sort of mistake causes unnecessary clutch wear.\n\nAt this point in the game, manuals are fully in the realm of the 'enthusiast option' as they no longer present advantages to the average joe consumer"
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bi1ddn | how are artificial color dyes made differently from natural color dyes? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bi1ddn/eli5_how_are_artificial_color_dyes_made/ | {
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"Natural dyes are made by taking something that's the right color and processing it into a dye.\n\nArtificial dyes are made by putting generic, commodity chemicals into a chemical reaction process that ends up with a dye."
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2gw40r | what did roger goodell do to cause such an uproar for him to resign? | I'm from London, and so not a lot of talk about Goodell here, but all I see on reddit is that he should resign, but not much of why. Any explanations will be appreciated. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2gw40r/eli5_what_did_roger_goodell_do_to_cause_such_an/ | {
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"He is the commissioner of the NFL and a lot of people are angry over how he handled the domestic violence controversy plaguing the league right now.\n\nRay Rice was allowed to stay on the team and play while the issue played out in the legal system. There was a lot of uproar over this and Rice has since been deactivated and let go from the Baltimore Ravens.",
"much of it because of a tape that eventually \"leaked\" to the press, through one of the websites, I think TMZ not sure. The tape showed Rice punching his wife and knocking her out cold in an elevator. Before the tape was shown to the public, there was no real outcry, although some concern, the basic concept was that he has to have his day in court first. And of course this concept has been play for many years in many sports, the problem has played out many many times in the last few decades. Its pretty standard to wait for a legal decision. \n\nOf course, Rice did get a legal decision, it was some sort of probation if I recall, and the league gave out a 2 game suspension as some sort of comparable punishment. (the league has rarely handed out any stiffer suspensions for any sort of criminal activity. I want to say never, there was some information released on this but rare or never has punishment exceeded this.) \n\nAlso, tangential, but part of the big picture, a St Louis Ram player Leonard Marshall had been found guilty of manslaughter for killing someone while driving drunk and he continued to play. This happened some years ago. Also last year, a New England player: Aaron Hernandez was arrested and held on murder charges, the evidence looks very bad against him. And then there was Rae Carruth a few year before that, he had his pregnant wife killed in a murder for hire, he's in jail. And then there was OJ Simpson 20 years ago. \n\nSo there is a large back story to all this. \n\nAnyhow, after the tape was shown, the outcry became immense because it is visually disturbing or perhaps for whatever reason. A few days after the tape was broadcast an anonymous police official told the media that he had sent that tape to the league, and even got a telephone call to verify that it had reached the league. He played the tape of the call to the press to prove it. But sending a police tape, part of an investigation to another party is dead wrong.\n\nBut the knowledge of the tape seems to be what got people most upset at Goodell (your own opinion may vary0 saying that Goodell had seen the tape he should have suspended Rice, because dont we all agree on how bad that is?\n\nAnyhow, I would stick up for Goodell on certain points. His league received criminal evidence from an anonymous source. How are they supposed to treat that? In all fairness, they should refuse to acknowledge it. That stuff should not have been sent them to and they should not be able to look at it and judge Rice. \n\nTHis sort of thing is happening a lot recently. THere was a scandal in Illinois when the governor Ryan and his wife who was a tv star, had some sort of sex tape leaked that was supposed to kept under seal. There was also the name of major league baseball players linked to PEDs in the Mitchell report that was supposed to be secret. But some jackass feels that it has to be out there. \n\nSo I can see Goodell's legal position on the tape; they just cant acknowledge stuff that is supposed to be secret and even worse when it comes from anonymous sources. But try to explain that to the public. "
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1656hu | did the Iliad change much or at all, over time? | would the common version of the Iliad in 495 BC be at all different from that of AD 298, for example? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1656hu/did_the_iliad_change_much_or_at_all_over_time/ | {
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"For the period prior to the third century BCE this is a very controversial question among the people who specialise in this area: probably you'll scarcely find two Homerists with the same opinion.\n\nIt's universally agreed that the text didn't change after the time of Didymos, a scholar who lived in the 1st century BCE. There is precisely one specialist who thinks the text changed between the third century BCE and the time of Didymos, but since he's the editor of the current standard edition of the *Iliad* (i.e. M. L. West), you can't really reject this as a fringe opinion, even if he is on his own. Almost all other Homerists would agree that the editions of Aristarchos in the 3rd cent. BCE settled the text in its final form (excepting transmission errors). So let's say it's a *majority* opinion that it didn't change from Aristarchos onwards.\n\nPrior to Aristarchos -- including the date you specify, 495 BCE -- things are a lot muddier. There are two main schools of thought: \n\n1. Some scholars believe that the text went through a kind of \"crystallisation\" process in the transition from oral transmission to written versions, so that it moved from a fluid, changeable text to something more fixed, but with lots of variation depending on where and when any given transcription was made. \n2. Others believe that the poem was written down straightaway when it was composed, so that any variation between then and Aristarchos' time was caused by avoidable errors in transmission.\n\nThose in the second group tend to regard those in the first group as delusional, since there's no *concrete* evidence for the first view. In fact there's no *concrete* evidence for the second view either; both views are driven by *a priori* considerations. The first view is driven by a belief that every aspect of the *Iliad* is traditional: traditional language, traditional scene-types, traditional plot-types, traditional myths. The second is driven by the fact that that's how *every other* ancient text works: an original version gets written by the original author, then people copy it and make mistakes.\n\nHowever, everyone's agreed that there was a fair bit of variation between the 6th and 3rd centuries. We know for a fact (because ancient commentators tell us so) that Aristarchos and other editors made use of many types of copies of the *Iliad* in their efforts to put together an authoritative text. There are three main categories: \n\n1. \"City\" texts, that is, official texts kept by individual city-states; these were normally high-quality texts with few \"errors\" (see above on the problem of deciding what \"error\" means in this context). Some city texts were especially prestigious, such as the Athenian one (and a few people believe that the Athenian city text was the first time the *Iliad* got written down; the reasons for thinking so aren't at all solid, but it is *possible*.)\n2. \"Vulgar\" texts: that is, the text of the *Iliad* as known to Joe Bloggs (assuming Joe has had a decent education). While not *radically* different from the core tradition, vulgar texts did have differences that seem very major to a textual critic. It is often suspected that many differences in vulgar texts were inherited from ongoing oral traditions preserved by performing rhapsodes.\n3. \"Private\" texts: high-quality texts in the possession of major scholars, like Eratosthenes or people of that ilk. These were on a par with city texts.\n\nHow *big* was the variation? Well, don't go expecting scenes playing out totally differently or anything like that: we're talking about things like one word or one line being substituted for another, maybe a group of lines in some cases, or lines being omitted. Some specialists would say that the presence of book 10 in the *Iliad* was caused by the Athenian city-text: that would be by far the biggest single variation. But you could expect the overall plot, the scene-by-scene structure, and most of the actual words to be the same across all versions.\n\nEDIT. A good example of the kind of variation that you could expect can be seen if you compare the text of the *Hymn to Apollo* (not the *Iliad* itself, alas) (a) [as preserved in the manuscript tradition](_URL_0_) (scroll down to lines 140-178), and (b) [as quoted by Thucydides](_URL_1_) at the end of the 5th century. Fairly big textual differences, but same poetic imagery, train of thought, etc."
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py447 | My professor uses a purple laser pointer I'm class and the dot always seems out of focus compared to a red laser. Why is this? | Is this a result of varying wavelengths that just my eyes can't focus on? Or is this universal with all human eyes? | askscience | http://www.reddit.com/r/askscience/comments/py447/my_professor_uses_a_purple_laser_pointer_im_class/ | {
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"In short, it's evolution. Green is the most common colour in the human environment, so our eyes have adapted to be best at seeing greens. Reds are important, as they indicate food or danger, however our eyes are not that great at seeing the upper end of the light spectrum, namely the blues into ultraviolet. \n\nYou may have noticed this effect when seeing standby lights on electronics in a darkened room. Green and red lights are easy to make out, however blue ones tend to be blurry.\n\nThere's a nice little article on it [here](_URL_0_) that has a nifty graph of how sensitive the human eye is to different wavelengths.",
"I was told by an optician a while ago that because of the placement of the cones in our eyes that are photosensitive to shortwave light, ie. blue and purple, we cannot focus properly. I think he said that the cones were less common and not positioned correctly to focus properly onto the retina causing blue lights to be blurry.\n\nHe was referring to some blue LED lights that we had in our house over Christmas. \n\nHere's two articles which support what he said, though neither are by reputable scientific presses, I can't find better sources though:\n\n_URL_0_\n\n_URL_1_\n\nedit: I linked the same article twice, instead of two different ones. Sorry. D:",
"Your eyes' resolution is less at the extremes of the visible spectrum (red, violet), as opposed to the middle (green). So the image appears smeared at the extremes of the spectrum, as opposed to the middle.\n\nAdditionally, the quality of the \"lens\" in your eye decreases towards the extreme wavelengths - it is less transparent, there's more scatter, etc.\n\nBottom line - it's normal. Any device performs less well at the limits of its intended comfort zone.\n\nA green pointer is brighter and looks more sharp, but it's less fancy. :)",
"Too bad I'm late to the party and will likely get buried. There are lots of good answers out there but nobody gets right to the crux. Khuskan points out that \"it's evolution\", which is a good answer but not helpful because *everything* about the human body is due to evolution. Crunchrapsuprem0 points out that blues \"wash out\" contrast, which is the same phenomenon but no explanation. Killartoaster points out that blue cones are less common than red ones, which is certainly correct but not the answer for why blues and violets appear out of focus -- after all, rods are highly sensitive to blue and have a high density throughout the retina. Paradox3121 asks a very astute question -- why do blue things on computer monitors appear fine? -- and Khuskan totally blows it by giving a spurious and factually incorrect answer. \n\nThe immediate physical answer is that, like most refractive materials, the lens (and cornea) of your eye refract blue light more strongly than red light. That is because the amount of energy in a photon of blue light is close to the chemical binding energy of many of the molecules in your lens (which, in turn, is why ultraviolet light can give you cataracts). As the light gets bluer it interacts more strongly with the lens, which slows it down more (so that the lens has a higher refractive index in blue than in red light). The upshot is that your eye's lens is more powerful in blue than in red. So you're nearsighted in blue. Nearly everyone is, even if they're not \"nearsighted\" under normal circumstances.\n\nIn the near field (like a computer monitor) your eye can adapt to the nearsightedness by relaxing the lens and focusing closer to \"infinity\" -- but it can't get all the way to \"infinity\" in blue, so there is a certain distance (depends on how well the rest of your eye works) beyond which blue stuff will go out of focus.\n\nThere have been experiments with achromaticity in human vision -- you can make special compound lens that compensates for the dispersion in the human eye. They are heavy and unwieldy and expensive, which is why you can't find them at Lenscrafters -- but they work like a champ, and raise overall acuity by bringing all wavelengths into simultaneous focus -- something you normally never experience.\n\nOf course, evolution drove the trade-off that left us all nearsighted in blue, and there are plenty of explanations for why elsewhere in this thread. But bobrobon deserves the straightforward physical answer: optical dispersion."
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dvzfnp | how do children acquire word meaning? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/dvzfnp/eli5_how_do_children_acquire_word_meaning/ | {
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"Tell someone to pick something up and make up a word. boom. They pick up a \"rock\" nah, that's a gangalafuck.",
"Most of it is context and repetition. You see a dog, you point at the dog, you say \"dog\". Your kid associates all things that shape with being a dog. Then you repeat that a million times a day for everything you see.\n\nWith other words, like \"what is that?\" They learn from our tone, and from what we leave out of our sentence. You see a dog, you point at a dog, you don't say \"dog\" so your kid says it for you. You get excited, they know they've succeeded.\n\nPlus listening to people talk normally helps them figure out what order words go in."
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2fypz0 | How do we identify smell of rotten meat as "sweet", what does it have in common with taste of sugar? | askscience | http://www.reddit.com/r/askscience/comments/2fypz0/how_do_we_identify_smell_of_rotten_meat_as_sweet/ | {
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"It's not the taste, but the smell. Certain molecules smell similar based of the molecules structure and what elements that are attached. The molecules released by the bacteria digesting the rotten meat would be a similar compound and have a similar structure to sugar. This means they would activate the same olfactory receptors."
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kana0 | How much electricity do I need to shock myself with before I feel it? | . | askscience | http://www.reddit.com/r/askscience/comments/kana0/how_much_electricity_do_i_need_to_shock_myself/ | {
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"It comes down to current. The rule of thumb that is taught in many places is the 1-10-100 rule: it takes 1 milliamp to feel it, 10 milliamps to prevent your muscles from relaxing to let go of the source, and 100 milliamps to mess with your heart enough to kill you. ",
"It comes down to current. The rule of thumb that is taught in many places is the 1-10-100 rule: it takes 1 milliamp to feel it, 10 milliamps to prevent your muscles from relaxing to let go of the source, and 100 milliamps to mess with your heart enough to kill you. "
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3hufx6 | Where does the term "Scandinavia" truly come from? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/3hufx6/where_does_the_term_scandinavia_truly_come_from/ | {
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"From to the OED: The name Scandinavia, which appears in the existing text of Pliny, is a mistake for Scadinavia, < Germanic *Skadīnaujā, whence by normal phonetic development Old English Scędenig (Beowulf 3336) = Old Norse Skáney (adopted in Old English as Scónég), the name of the southern extremity of Sweden; the terminal element is *aujā, Old English ég, íg, island.\n"
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1m718d | how do employer personality assessment tests work and how could someone possibly fail one? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1m718d/eli5_how_do_employer_personality_assessment_tests/ | {
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"If you're applying for a sales position (or any customer-facing position), but your personality test indicates that you're strongly shy and introverted, they might consider that a \"fail\". It's not a judgement of you as a person, just an evaluation that perhaps you may not have the disposition to be well-suited for the position in question.",
"You don't \"fail\" personality tests. They are supposed to show whether you are a good match for a position. If you were non-confrontational, you might make a poor security guard. If you were extroverted, you might make a poor researcher.\n\nAs for how they work, not everyone agrees that they do, and their use remains controversial. The often will ask you questions like \"which of these do you prefer?\" or \"What best describes you?\", and give you options to choose. After enough questions, trends emerge that are supposed to give insight into your personality."
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80hfk7 | if the sun and moon are both visible (and well above the horizon), how could the moon still have a shadow? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/80hfk7/eli5_if_the_sun_and_moon_are_both_visible_and/ | {
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"About half of the Moon is always in shadow, just like Earth. The lit side of both spheroids is the side facing the sun. The only time we can't see that shadow is when the moon is on the exact opposite side of the earth from the sun. ",
"The moon's shadow is the side that isn't lit by the sun. It's not a place where the sun's light *would* shine, but is blocked by something else. \"Shadow\" is a bit of a misnomer. Half of the moon is in \"shadow\" at any given time, including when it happens to be visible alongside the sun.",
"Grab a tennis ball and a lamp. Turn off every other light in the room. Hold up the tennis ball. Half is lit, half is dark. If you are looking from the side (you can see the lamp and the ball) you can see some of the dark side of the ball. \nThe ONLY way to see nothing but lit ball is to have the lamp directly behind you, with the ball just outside your shadow. EVERY other angle that you look at the ball will expose some of the dark side."
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72xnok | why are polygons in 3d modelling software by default triangles/rectangles (pentagons & up) | title is sort of vague, but I've worked in a few 3D modelling programs and while you can have as many vertices to one polygon as you please, and even make your own shapes, but they are by default only made as triangles or rectangles,
(excluding circles.) I've always wondered why instead of using less vertices, and polygons to make something like a pentagon or hexagon, they will default to using 1 triangle, 1 rectangle, or 2 rectangles. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/72xnok/eli5_why_are_polygons_in_3d_modelling_software_by/ | {
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"Any polygon can be divided up into multiple, adjacent triangles without changing the vertex count. Math for interacting with 3D object can be quite complex, but it can be made much simpler if you know that every face is a triangle. You write code to test points against triangles and you can use it on any mesh of triangles. So algorithms for things like collision detection, occlusion, and shading can all rely on the same math equations. And the hardware can be optimized to do this kind of math in parallel.",
"Triangles, as the simplest polygon, are the easiest to process and draw. You don't have to worry about weird cases where the vertices aren't all in the same plane, producing some sort of curved surface - an issue as soon as you go beyond 3 vertices. Edit: plus they have the useful property that they are always convex (all interior angles less than or equal to 180 degrees) which makes some geometric calculations easier, e.g. viewport clipping and ray-polygon intersection. Once again this property is not guaranteed with more than three vertices.\n\nGraphics cards are also heavily optimized to deal with triangles; if they even accept more complex polygons, there's a good chance they're converting them to triangles under the hood anyway.\n\nIt keeps everything simpler all round just to work with triangles.",
"Polygonal modeling isn't actually the only type of modeling, though it's probably the most common in games. You have NURBS/NURMS which modeling that is based off of curves. Nurbs is more common in product design. You have surface and patch modeling and sub-division modeling where you're making a cage and sub-dividing with tessellation to generate the surface. You also have parametric solid modeling typically CAD that's based around actual machining proceses.\n\nThat being said, polygonal modeling is dominated by triangles today because the process is optimized for a triangle. A triangle is simple form of a mesh. You can just as easily make a \"nGon\" in Maya, which is a polygon made of n sides.. usually more than 4. The problem with nGons when applying a blinn type smoothing algorithm that makes surfaces appear to be smoother but without adding geometry is that you'll often get poles or pinches in the smoothing. Game engines, especially older engines relied on these types of geometry smoothing algorithms to improve visual quality, which makes it bad modeling practice for games. Gaming optimisation is centered around cutting surface counts as well as limiting draw calls, which makes breaking every piece of geometry down to a series of triangles means using the least amount of verts and surfaces as possible and knowing where the lines of the two Tris that make up a quad are allow for better topology when volume for animation (example, laying out your quads very specifically when creating a human face to mirror the muscular structure). If you're making nGons, then how the geometry bends to the animation could make unintended pinches and transitions.",
"Triangles are the \"atom\". You can divide everything into triangles, but you cant divide it further. So, it becomes a practical common ground for every part of the system to work with. Having one basic shape means that you can focus optimizations heavily on that.\n\nAlso, as soon as you get more than three points, they can be on different planes. Take a piece of paper and lift two corners, creating a \"valley\". Now, flatten the paper and instead hold it high and bend down the lower corners, creating a \"ridge\". Now, from the same corner positions (coordinates), you've created to completely different shapes. Say that you wanted to trace a ray of light through what you interpret as a valley (or fly a cruise missile through it), and it actually was a ridge, that wouldn't give the intended result.",
"Imagine a perfectly square piece of paper, lying flat on a table. The square has 4 corners, and if you imagine that 3 of the corners are attached to the table, and you start pulling the 4th corner away from the table, then the paper would fold. You would end up bending the original flat square into two triangles.\n\nNow think of a pentagon, with its 5 corners, and you attach 4 corners down to the table, and then pull on the fifth. Once again you'll cause a bend in the original shape, this time creating a triangle and a quadrilateral.\n\nNow take a piece of paper cut into a triangle, and attach 2 corners to the table. Pulling the third corner will not cause the triangle to bend into other shapes. You still have one entire triangle. In fact if you move the other two corners around as well, you will still always have just a single triangle with no bends.\n\nMathematically, this is because, when working in 3 dimensions, it takes exactly three points to define a flat surface (\"plane\"). Any more points than that, and you can no longer guarantee that the surface created by those points is still flat.\n\nAnd having perfectly flat objects to render makes the math needed to draw 3D objects on a 2D surface as fast and reliable as possible.\n\nWhen games and other software draw things that look curved, generally this is done as a lighting effect. Older games look angular and chunky because they didn't have enough processing to perform lighting calculations on every pixel of every triangle, causing the underlying edges of the triangles to show through. These days, graphics cards perform a crazy number of lighting calculations on every pixel drawn, so a gradient of colors across an otherwise flat triangle gives the illusion of a smooth curve without any edges."
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g1lhbq | Why did ancient people make soap? | They didn't understand germ theory so what was the point? The Gauls made soap in Europe however they used animal fat which I would think would be quite valuable otherwise so why were materials used to make soap when they didn't know the implications of this invention? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/g1lhbq/why_did_ancient_people_make_soap/ | {
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"Because you don't need germ theory to understand hygiene and general cleanliness. Some reading I dug up for you:\n\n* u/Somecrazynerd offers a [general overview on hygiene](_URL_1_);\n* u/BRIStoneman here examines [Anglo-Saxon and Norman hygienic practices](_URL_2_);\n* and u/DownvotingCorvo [looks at Aztec hygiene](_URL_0_), showing that thoughts of hygiene and cleanliness aren't limited to Europe."
]
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"https://www.reddit.com/r/AskHistorians/comments/6qiuu0/was_aztec_tenochtitlan_relatively_hygienic/",
"https://www.reddit.com/r/AskHistorians/comments/do0iof/what_level_of_hygiene_was_expected_of/",
"https://www.reddit.com/r/AskHistorians/comments/bqjfh7/what_was_the_reason_for_the_decline_of_basic/"
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oqnw8 | If you were woken up while sleeping, would you resume your sleep cycle or start over again? | For instance, let's say that someone called in the middle of the night and woke you up for a brief amount of time, then you fell back asleep. If before you woke up you were partway through a full sleep cycle and had not yet reached REM sleep, would your body start a new cycle when you fell back to sleep, or would it sort of "resume where you left off" in the interrupted cycle? | askscience | http://www.reddit.com/r/askscience/comments/oqnw8/if_you_were_woken_up_while_sleeping_would_you/ | {
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"Hi all, first Reddit post, been lurking for a couple weeks now and thoroughly enjoying everyones posts. \n\nI'm a sleep tech, I study how people sleep, help in the diagnosis and treatment of sleep disorders. While there is an expected textbook progression through the different sleep stages our bodies don't always follow that path exactly. It is absolutely possible for someone to wake from one stage of sleep and then return back to that stage immediately, this includes deep and REM stages. It is also not uncommon for people to flip flop between two stages (Stage 1 to 2 then back to 1) or to skip stages completely (REM straight to 2, skipping stage 1). \n\n*Sleep techs do it all night long* "
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fsj94p | Why do some trees like Avocado trees have red leaves at first but then they turn green? | I hadn’t noticed that beforehand until I got an avocado tree at home. There is another tree on my block that also has red leaves first and then they turn green with time. | askscience | https://www.reddit.com/r/askscience/comments/fsj94p/why_do_some_trees_like_avocado_trees_have_red/ | {
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"Delayed greening of leaves is very common in tropical trees like avocado. There are several hypothesized reasons. Green leaves (chloroplasts) are more nutritional for herbivores and costly for plants, so plants want to avoid them being eaten when young. Red colour is from tannins and anthocyanins which protect leaves from herbivory. The colour protects juvenile leaves from UV damage and photo-inhibition. \n\nSome source:\n_URL_2_\n_URL_1_\n\nUse _URL_0_ to open these if you hit paywall.",
"The dominant photosynthetic pigment in plant leaves is chlorophyll-a. Chlorophylls colour the leave green. However other pigments are usually produced as well and may be more prominent either in newly grown or senescing leaves. Carotenoid pigments in particular are most efficient at absorbing blue light (and help protect against UV light) which means they cause the leave to reflect relatively more red light. This is likely what you see."
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1d6a20 | when does it stop being an homage or reference to another great work and cross over to becoming plagiarism/stealing copyrighted works? | I often hear stories about how certain movie or TV show lines are references to other movies/TV shows. How come these are okay, when I doubt that the writers tracked down the original creators and asked permission to use those lines? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1d6a20/eli5_when_does_it_stop_being_an_homage_or/ | {
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8dhhtj | How does the current shift away from the concept of "feudalism" in medieval scholarship impact the understanding of statebuilding and the centralization of power in the early modern era? | A common theme hammered upon by the medievalists of our find subreddit is that the concept of "feudalism" is wrong \- "feudalism doesn't real" \- and that the term has mostly been abandoned by medievalists. But even in fairly recent academic publications I still see it used by non\-medievalists. For someone writing about the 20th century and mentioning it as an aside, that might just represent the fact they aren't plugged into current streams of medieval scholarship, but one place where it seems to still be a term of use, and an impactful one at that, is scholarship which discusses European statebuilding and the centralization of power in the early modern period with local leadership losing power i.e. discussing it as a movement away from the decentralized feudal system which featured weak central leadership and comparatively stronger, local leadership who owed nominal allegiance to that central leader.
So in short, my question is how should we understand this transition, and how should we understand the term "feudalism", when discussing the early modern period as a contrast with the political structures and organization of the medieval period.
Bonus question: The other place it still seems pretty popular is in medieval \*military\* history. Are the MilHist medievalists just behind the times, or are they less concerned about the terms applicability in a strictly military conceptualization as opposed to a socio\-political? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/8dhhtj/how_does_the_current_shift_away_from_the_concept/ | {
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"Well I must say I'm quite surprised to learn that the notion of feodalism is being challenged. As a young medievist from a non anglo-saxon country, I've yet to find a single questionning of this concept, and the term is still very relevant in the medieval schoraly works that are written today. Now ti wouldn't be the first time that my country is a little behind in term of historiographic innovation, but could you please link me to some of those rebuttals ? I'm more than a little interested by those views and the arguments utilized.",
"I'm not really qualified to comment on your overall question, but I can offer some thoughts on this:\n\n > Bonus question: The other place it still seems pretty popular is in medieval \\*military\\* history. Are the MilHist medievalists just behind the times, or are they less concerned about the terms applicability in a strictly military conceptualization as opposed to a socio\\-political?\n\nMilitary History has a not entirely undeserved reputation for being one of the more ‘backwards’ fields in academia. It’s a bit of a broad, sweeping statement but MilHist has generally been less willing to engage with new developments in historiography, and certainly has been reluctant to adopt less traditional historiographical methods/frameworks \\(there aren’t a lot of Radical Feminist MilHist scholars, for example\\). Military Historians, I would argue, are more likely \\(when compared to their peers\\) to take the view of ‘just doing history’ rather than exploring the epistemological framework of their research.\n\nI don’t want to paint an entire discipline with one brush, however, and there are many excellent Military Historians who do engage with broader historiography and methodological matters in the pursuit of their research. This brings me to another difficulty when discussing MilHist, though, which is that it’s very popular. I would argue that it is second only to Political History \\(that old classic\\) in terms of its popularity with a general audience, and it draws in one of the widest pools of non\\-academic authors \\(it’s particularly wide if you include ex\\-soldier’s memoirs, but even excluding that a lot of ex\\-military types write MilHist books\\). This popularity is far more prevalent for modern military history than medieval \\(*Band of Brothers* and its ilk are a lot more famous than anything focusing on the Middle Ages\\), but more than any other discipline the modernists dictate the tone of Military History, so what’s happening there has an impact on what medievalists are doing in the same field. I read a great article on how medieval military history has been influenced by the dominant focuses of other periods \\(mostly modern\\), but I can’t find the link right now. I’ll see if I can dig it up when I’m back home, I think I saved a copy on my laptop. It’s a very subjective account from a military historian, so I wouldn’t say it’s the definitive word, but it’s a really interesting read.\n\nThe presence of a ready popular audience influences the kind of works that get published in Military History. There’s a lot of focus on generals, battles, campaigns, and military equipment than on broader cultural, social, etc. issues. This could be roughly described as the ‘Historical Badasses’ history. I want to reiterate here that this is not the totality of the field, and the best books cover a wide range of topics, but there are so many of these pop histories that it can kind of dilute the excellent books, particularly if you’re coming into it from the non\\-academic side. There also tend to be fewer academic posts specifically for military historians \\(it’s not seen as the most necessary area for a department to cover\\), which generally means more scholars are located outside of academia. I’m not one to suggest that people not working within universities can’t publish great history \\(I don’t, and I still aspire to write a book\\), but I think the different setting, and how common it is in the field, impacts the broader trends within the scholarship \\(at the very least, the need to make money off of ones books probably helps skew the more popular trends in book subjects/styles/methodology\\).\n\nThat’s a lot of words where I’m not answering your question, all building to a rather meek answer of: it depends. I would say broadly that medieval Military History doesn’t engage with the question of ‘Did Feudalism Exist?’ but for two very different reasons. I will continue my trend of sweeping categorisations by classifying them into two groups: Battle Histories and Logistic Histories.\n\nI have, in the past, shown some contempt for Battle Histories \\(probably unfairly, but you’ll never hear that from me\\). These works focus on detail on battles or campaigns. Some of the best books in this area are on all aspects of a single battle \\(see Anne Curry’s *Agincourt* for a great example\\), while others link together multiple battles to form a larger narrative \\(see\\* DeVries Infantry Warfare in the Early Fourteent\\*h Century for another good example\\). The best of these are great scholarly works, the worst are usually ^(a)t least a good read.1 These accounts often start at the beginning of the campaign or battle, and don’t spend a lot of time on how the armies were assembled or what led to them getting there \\(soldiers were summoned, they came, that’s enough\\). Some do \\(Curry is famous for it\\), but it’s certainly not required and in pretty much all cases these histories don’t have to engage with Feudalism on a critical level, and so they don’t. \\(As an aside, for my part I dislike most Battle Histories because I think they ignore too much of the broader context of the battle in favour of charts and diagrams showing precise troop movements and what I feel is often needless detail about the conflict\\).\n\nLogistic Histories focus more on the financing, supplying, and complex paperwork involved in the waging of war. In my mind the poster child for these kinds of histories is Michael Prestwich, whose *Armies and Warfare in the Fourteenth Century* is an excellent example. Few of these books/articles, that I’ve read anyway, deal directly with the issues around the Feudalism Debate, but I would argue in another way they kind of do. Prestwich doesn’t say whether Feudalism is real or not, for the most part his work is largely disinterested in it \\(he may personally find it interesting, though, I don’t know the guy\\). What these books do, however, is show – often in great detail – how armies were assembled, supplied, and transported from conception until pretty much right up until the battle. In this way I would argue that they often show the nitty gritty of how feudal government worked in a very specific circumstance. The difficulty with the Feudalism question largely lies in attempts to apply a singular form of government/management to the entirety of medieval Europe, and these types of histories largely avoid that by being so specific.\n\nI’ve outlined two of the most common areas of medieval military history above, and why I think they mostly ignore the Feudalism debate. You could, in fairness, probably boil it down to the idea that both tend to be so specific in focus that they kind of sidestep the issue, even if they don’t realise it. What I have neglected to discuss is the General History, the Big Book of War where someone writes their magnum opus on A Medieval War. I’ve kind of avoided this because I think it’s a really tricky thing to pin down in the Middle Ages. Medieval military history is a small field, and by and large it focuses on the sort of detailed studies in the above two categories. Sweeping general histories of wars tend to be covered in political history \\(in the Middle Ages anyway\\). Take my other flair for an example, there are tons of histories of The Crusades, an event \\(or series of events\\) of a primarily military nature that could be classified as ‘a war’, but very few of them are written from a military history background. There are detailed histories of parts of the Crusades and its battles/sieges, but general histories tend to come from a more Political/Religious history background. The same is often true for The Hundred Years War, or the Anarchy, or any number of other major medieval military conflicts. I think this is in part due to the small size of the field, but I also think it’s an acknowledgement of just how closely intertwined warfare was with politics in the Middle Ages \\(not that they’re not intertwined everywhere else, Clausewitz wasn’t talking completely out of his ass with ‘War is politics by other means’, I think it might just be that medievalists are slightly more aware of it\\). I would say that by and large I don’t think most general histories of medieval wars engage with the problems of the Feudalism question, but I also wouldn’t say they’re much more egregious than any other general medieval history. I don’t think Anne Curry’s very military focused *The Hundred Years War* is worse for this than David Carpenter’s more politi*cal history The Struggle* *for M*astery.\n\nI’ve also completely ignored the other classic area of medieval military history, and the one closest to my own heart, the history of military technology. These only sometimes deal with people or society, so they basically just ignore Feudalism entirely, except for a handful of more popular histories that have a tendency to make egregious overstatements about how English archers represented the working plebes rising up to prominence because something something plucky British Tommy. I probably don’t have to point out that these latter works generally don’t represent the greatest level of engagement with society and culture in the Middle Ages.\n\nFinal disclaimer, this answer is a lot more subjective than I usually like. As a late medieval Medieval MilHist research myself \\(although for branding purposes when I was briefly still hopeful of a job in academia I was a Historian of Technology\\) I’m less able to pretend towards objectivity than normal and discussing a field as a whole always requires sweeping statements based at least in part on one’s own experience. I haven’t read every book on medieval military history, and my reading has necessarily focused more on my areas of research/interest than others, so I’m sure there’s plenty of room for others to dissent with my take. I am particularly ignorant in early medieval military history, so it’s entirely possible that they’re having some great aul’ discussions of Feudalism there and I’ve totally missed it.",
"My apologies for the delayed response!\n\nYou're making one very big assumption here, which is that early modernists care what medievalists say. ;)\n\nI'm being uncharitable, of course, but not entirely inaccurate. As it turns out, rethinking feudalism isn't really a paradigm changer for early modern European historiography--but that doesn't mean that early modernists can ignore what's happening in medieval studies. To understand this, let's look at what the feudalism debate is and isn't, and the era of scholarship in which the idea of \"feudalism\" and \"feudal society\" took root. For current purposes, feudalism will be used socio-politically, to designate a practice of one person holding land in exchange for fealty and service to a superior, *not* an economic/Marxist definition.\n\nAs I mentioned elsewhere, the two \"feudalism didn't real\" works everyone knows are Elizabeth Brown, \"The Tyranny of a Construct,\" and Susan Reynolds, *Fiefs and Vassals.* Essentially, Brown pointed out that the way modern medievalists use the word \"feudalism\" means something different in every scholar's use! Thus, the word itself has no ability to convey actual information; it's a proxy for what each reader *thinks* it means. Reynolds, on the other hand, argued that not only does feudalism lack a solid modern meaning, but the words that make it up - f.ex. fiefs and vassals *bet you didn't see that one coming!* - lack a consistent meaning in *medieval* sources.\n\nIn other words, she read a billion and a half surviving charters (documents memorializing property transfer) from 900-1100 and *analyzed the meanings of individual Latin words.* This is the most medievalist of medievalists' research, and goes at least part of the way towards why early modernists' eyes glaze over and also why we say \"read book reviews of Reynolds\" instead of the actual book.\n\nBut herein lies the other, less sarcastic wrinkle: 900-1100. Supporting Reynolds' argument against set meanings for words like *feodum* in this era is a larger argument about the status of standardized law (customary law, but still rather standardized) in the central Middle Ages. Although there are slowly gathering scholarly and political forces earlier, it's really the century *after* 1100 that works out systematized conceptual structures of law. (And as current scholarship is showing, it took even longer for the concepts and the paperwork to implement them to have a *major* 'standardizing' effect on medieval governance.) There are a lot of years between the Ottonians and Maximilian, and a *lot* of regularization of the concepts of nobility, hierarchy, property rights and liberties, government, and law.\n\nBut while the terms of debate over \"feudalism\" don't bear so heavily on 1500+ historiography, the broader movements in scholarship to which it contributes absolutely do. This is where we have to consider what \"the Middle Ages\" and \"the Renaissance and Reformation\" looked liked to scholars when the idea(s) of feudalism took root(s) - there was no \"early modern era\" yet. I will have to swing a sledgehammer here and miss a lot of nuance in the beginning, but seeing as I have already determined to way overanswer your question, I might as well go all the way. ;)\n\nThere are two really defining features of late 19th/early 20th century medieval scholarship, one of which is rather known but somewhat misunderstood today, the other of which is generally forgotten to popular/school education knowledge. First is the gradual circumscription of \"the Dark Ages.\" From Petrarch's \"middle age\" to Gibbon's Christianity-shadowed decline and fall of Rome to Burckhardt's \"civilization of the Renaissance,\" the long-entrenched idea was the whole shebang as a Dark Age (which nevertheless cultivated the seeds of modern European nation-states). The so-called revolt of the medievalists said no, not so much--but by focusing on the twelfth and eventually the thirteenth century. The Dark Ages got pushed back to pre-1000; meanwhile, the centuries after 1300 were seen as a morass of unending Crisis.\n\nFuture generations of medievalists attempted a rebranding: the early Middle Ages and the late Middle Ages (surrounding the high or central MA). But \"early\" and \"late\"--or in French, \"high\" and \"low\" (haute, bas)--carry different connotations that continued to paint the late MA as a bad time to be alive.\n\nMedievalists have of course been complicating and disputing *that* narrative for awhile now. And they have been doing so by fixing the other big problem/characteristic of earlier scholarship I mentioned above: the reintegration of religion into medieval history.\n\nI know that sounds odd, borderline unbelievable--medieval history without religion? Yup. The geopolitical nation-state-building paradigm was strong, retrojecting modern Europe onto the Middle Ages. Heck, Haskins' *The Renaissance of the Twelfth Century* centers entirely on secular revival of Latin classics; it's not until Leclerq publishes *Love of Learning and the Desire for God* in 1961, around the time of Giles Constable's early \"reformation of the 12th century\" lectures, that scholars began to accept the intellectual role of monks! (Nuns will take more time, although *Haskins* at least name-checks Herrad of Hohensburg). This ties in with the general turn towards cultural and religious history, which will go on to overwhelm and permeate every inch of subsequent medieval scholarship.\n\nThis is not to say history of religion was *ignored*. Hardly! I fangirl so hard the 19th century German scholars who did *stunning* paleography, editing, and basic fact-compiling scholarship on so many religious texts and people, including marginal women (!). But this work was not part of Mainstream History--it was boxed off as \"confessional\" and sometimes even \"devotional,\" meant for adherents of a particular branch of Christianity mostly for spiritual edification (or the opposite--to debunk it). \n\nBut what has this to do with early modernists? Well, confessional religious history was even stronger there--until the 1970s or so, Catholic, Lutheran, Calvinist/Reformed, and Mennonite scholarship on the continental Reformation *did not talk to each other*. And they were competitive: religious history meant \"this is why we were right and are better\" the same way political history \"proved\" the solidity and priority of modern nation-states.\n\nSo when *medievalists* began revisiting the Crisis of the Late Middle Ages paradigm, one of the big ways they did so was by uniting geopolitical and religious history: they observed the ways the medieval Church acted as a \"polity\", a political entity. This had been invisible earlier thanks to the retrojecting of modern politics onto the medieval map. Ditching a teleological \"*state* formation\" narrative and focusing on what polities were acting, what they looked like inside and out, had helped medievalists trace a trajectory of consolidation and expansion over even the \"crisis stricken\" \"late\" Middle Ages.\n\nTHIS is the narrative that early modernists need to heed. And there are absolutely signs of this--Thomas Brady's *German Histories in the Age of Reformations* is a stunning example. He traces the 15th century imperial reforms in conjunction with the failure to reform the Church at the international level, but with the German nobility mirroring their secular political reforms over their *territorial* churches and monasteries.\n\nBut there is still one big intellectual stumbling block between medievalists and early modernists communicating. (The structure of the historical profession is another problem, but that's another thread). That is the *early modern* narrative of state formation/modernization, known as confessionalization. This is the idea that states centralized political power and social power (solidification of sovereignty in the international scene, and legitimacy of rule/power to enforce law over people living in its borders) with the aid of the confessional church in their region (Catholic, Lutheran, etc)--but along *parallel* trajectories, not special ways.\n\nAs asserted thus, it is *impossible* to trace a prehistory of confessionalization because there are no confessions before 1523. Early modern scholarship and medieval scholarship speak incompatible languages.\n\nThere are a few early modernists who are trying. Erika Rummel's *Confessionalization of Humanism* asserts a common intellectual origin for the eventual bitter divide of the intellectual world between Protestant scholars and Catholic humanists. William Bradford Smith's book on territorial politics in Franconia traces a gradual split and political distinction between two local polities in the 15th century that, after the Reformation, will adopt different religious confessions thanks to their political and economic ties/needs. I consider this one of the most influential history books I've read, but he (and Rummel) have gotten A LOT of pushback. Because you can't have confessionalization without confessions.\n\nSo to conclude this massive overanswer, the crisis of feudalism scholarship hasn't really affected early modern political-social history. However, the ideas and problems that play into it--state formation, social hierarchy and discipline, and the power of modern names for phenomena imposed on a past--are absolutely something that both medievalists and early modernists need to negotiate. To negotiate *together*."
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2wjdju | why is a 'swiss bank account' such a bigger thing than other countries bank accounts? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2wjdju/eli5_why_is_a_swiss_bank_account_such_a_bigger/ | {
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"Someone explained this a long time ago to me. IIRC, it has something to do with Switzerland's odd banking policies. People who want to evade taxes or hide their money (especially if it was made shadily) put their money in a Swiss account. Even if they get in trouble in their own country, their government can't seize the money due to the Swiss laws. ",
"Switzerland has very strict privacy laws regarding banking - it is illegal for a bank to reveal the identity of an account holder. It also has a very stable economic and political position which means it is generally a safe place to keep your money.\n\nEDIT: the court can order the bank to reveal the identity of an account holder if it is deemed necessary. This includes account holders from overseas.",
"It's not \"bigger\" and it's not just for rich people, lots of people have swiss bank accounts. here are a few reasons:\n1) Laws make your info private, no one will know your account exists.\n2) Swiss economy is stable and your money is safe\n3) Swiss currency is stable and somewhat protects your money from inflation. Example if you deposited $20,000 in 1980 in a USA bank, that would have been a quite decent annual income for that time. but withdrawn today, you'd be at the borderline poverty level in terms of annual income. So your money actually de-valued.",
"Can anyone ELI5 how this relates to Nazi gold? I thought that those accounts were just recently disclosed and there was some plan to return the money to the families of the jews murdered during the Holocaust...",
"The answer is that they aren't, not anymore anyway, but everybody knows what you're talking about when you say \"Swiss bank account\" which means that people keep using the term. \n\nSwitzerland has recently rolled back their bank secrecy laws, mainly due to the immense pressure put on them by the US and Europe (they want their taxes), making it much less appealing to people with money to hide. Those people have moved their money elsewhere and there are still many places around the globe that are eager to accept money of dubious origin (\"Sunny places for shady people\").\n\n\"Swiss bank account\" as a term is here to stay, even though it now refers to a no questions asked philosophy more than something located in the country of Switzerland.\n\nCome check out /r/MoneyLaundering if you're interested!",
"The Swiss used to be able to store your items without scrutiny, but recently they're becoming more and more obsolete ",
"During WW2, the Nazis appropriated bank accounts, and made it illegal to move money out of the country (and out of their reach). People moved the money anyway, and Switzerland was a favored destination. Nazi investigators would travel to Switzerland and bribe bank officials to reveal the names of Germans who had moved money (who they would promptly execute). The Swiss government learned about this, and passed laws making it a crime to reveal banking details so that the bribed bank officials could be prosecuted.\n\nLater, criminals discovered that these laws were convenient for concealing their ill-gotten gains. Swiss bank accounts became synonymous with shady money. Foreign governments began pressuring the Swiss to reveal more banking account details to them so they could more easily discover and prosecute tax evaders and other criminals. The foreign governments threaten to cut Swiss banks out of the international financial system. This is a potent threat, and so the famous Swiss banking secrecy has eroded over the past few years.\n\nOther countries have stepped in to fill the void.",
"To REALLY answer your question, \"Swiss Bank Accounts\" AREN'T a bigger thing than other countries bank accounts. \n\nThey WERE, however. And the reasons have already been outlined here I imagine. Swiss banks were regarded as an extremely safe place to store funds discretely. All that changed, however, upon the U.S. investigation into UBS clients a few years back. To be perfectly honest, it's been changing for years at this point.\n\nMy former boss did have banking arrangements with UBS but it was one of four now global banks that his arrangements were with that runs the gamut from Citibank (U.S. based) to Barclay's (British based). The fact of the matter is that nowadays it matters precisely not at all whether your assets are located in a Swiss based bank. There is no tax advantage, no privacy advantage, and certainly no rate advantage (UBS was never competitive with either time deposits or currency exchanges.) Swiss banking is really on the way out as Ultra HNWIs don't see the benefit of them anymore.\n\nWhat has replaced the Swiss banking arrangement has been the Cayman Islands Holding Corporation, the Luxembourg Limited Parternship, or BVI companies. My former boss is a Greek citizen but because his holding corporation is based in the BVIs and he resides in Monaco, he paid nothing in taxes on either his holding corporation or individual level in 2014, a year in which he earned and deposited apprxoimately £300 million in various accounts. There was no preference given to Swiss banking except as a means of diversification.\n\ntl;dr: Swiss banking is not a bigger thing than banking in other countries anymore",
"Long story short: they ~~don't~~ didn't snitch!",
"Several years ago the US Gov't had a huge lawsuit for them to give up 5000 accounts suspected in criminal investigations. They fought it tooth and nail and ended up giving about 5%. ",
"The Swiss have NO ETHICS whatsoever. Swiss banks gladly accepted the illegal seizings of the Third Reich... the property of millions of Jews, including the gold from their melted-down teeth fillings. The Swiss basically covered their eyes and ears and said \"bring us your Nazi gold... we'll keep is safe for you and won't ask any pesky questions about where any of it came from! Wink wink!\"",
"I don't know why it would be now, but one of the things that was very important earlier. Was the Swisses ability to remain neutral, in past wars. And where would you rather likely be putting your money? In a bank that can survive a \"catastrophy\" or a bank that is very likely to be conmdemned bankruptcy because of a war?",
"Swiss banks use Switzerland's privacy laws to hide money for criminals.",
"Secrecy. \n\nSwiss banks were notorious for keeping information of their depositors away from foreign tax collectors (among many other national agencies). And while they did have to report any suspicious transactions, rarely did they provide information about their customers who had presumably committed tax fraud in their home country. This was largely in part due to the Swiss' narrow definition, where non declaration of income and assets was only qualified as tax evasion, which was not a crime according to Switzerland. \n\nThere were many law suits by the U.S. against UBS (a Swiss bank) in 2008 to 2011 involving the OECD (US Organization of Economic Cooperation and Development) and the G20 (UN group of 20 nations) to require member states (including Switzerland) to \"provide information about foreign taxpayers as long the requesting country provided prima facie evidence that they had violated the requester's domestic law.\" (Switzerland: Foreign Pressure and Direct Democracy by Julio J Rotemberg and Jonathan Naharro Martin[requires Harvard Business Review subscription])\n",
"People who use the term \"anonymous numbered Swiss bank account\" don't know what the hell they're talking about. Swiss accounts have never been completely anonymous. Swiss banks want to know as much about the client as possible so they can provide the best service possible. The point of a \"numbered account\" is to protect the privacy of the holder from low level bank employees. Only senior bank executives have access to the holders identity and those executives are often barred from leaving the country for fear they will be arrested and forced to divulge bank secrets. After 9/11 the US came down hard on international banks, as a result their impenetrable wall of privacy is mostly gone. The banks have changed focus from asset protection and privacy to providing higher returns with lower fees. \n\nIf you want a truly anonymous account you have to go through a process called 'layering'. This involves setting up a large network of shelf companies and trusts through multiple jurisdictions in places like Panama, BVI, Nevis, Belize, Cyprus and Hong Kong. The money is then routed through the companies in several different ways to obscure the source. This is how despots and dictators hide their money. There are a number of shady law firms that specialize in layering. \n\nYour average wealthy family can easily avoid taxes and protect their wealth through some straight forward and completely legal means. Trusts are a wonderful thing. \n\nTL:DR; Banking privacy is gone, rich people don't need to break the law to avoid taxes. \n\nSource: Family has Swiss accounts, as do friends families. ",
"It's not anymore. It used to be because they were super secret and wouldn't tell anyone else about your money, but now Swiss banks roll over for the US government like other banks.",
"Because, the moment you mention you have a Swiss Bank account, you get the chicks.",
"The best response is that it's purely a perception issue. As SZ was one of the most stable and favorable banking regimes around, and also had the most stringent secrecy laws about disclosure, a Swiss bank account used to be the preferred vehicle for hiding money overseas and not reporting income to the US federal government. There are also stories about drug dealers, terrorists, despots, etc. keeping tons of money in these accounts, using them to launder money, that kind of thing. There is a (from the US perspective) social stigma associated with having one. It implies that they are attempting to dodge taxes.\n\nWith the recent changes in legislation (and some momumental political black eyes), the Swiss have enacted some transparency to their banks. Whether it's real or window-dressing is an open question, but it seems to be resulting in some cases of tax fraud being located.\n\nIs it a 'bigger thing' than other countries? Nope. For instance, the Cooke Islands has incredible stringent banking secrecy laws, no interest in changing, and is a preferred place to launder money/evade taxes. It's just the average guy on the street hasn't heard about them.\n\nSwiss bank accounts don't currently deserve their social stigma, though at one time they most certainly did.",
"Because until recently they would take money from absolutely anyone. The mistake they made was helping americans evade taxes so now they can't do that anymore. But it remains the destination of choice for dictators, corrupt politicians, criminals and other non-americans with ill gotten wealth to hide. Switzerland has gotten fat off money siphoned by third world politicians. They come into power with the help of the American CIA and steal with the help of Swiss banks.",
"You're going to hear a bunch of fluff about privacy, but what it boils down to is tax evasion by foreign account holders is not prosecuted nor does it result in frozen assets, and the Swiss bankers who abet them are held harmless in the process.\n\nAll you'd have to do is charge less than the marginal tax rate on the investors next dollar. As you can imagine, this is insanely profitable for both the Swiss banker and the tax evader.\n\nEdit: wording",
"Tax avoidance.\n\nSwitzerland operate on a *neutral* footing - they try to not align to any particularly nation, ideas, interests.",
"Because Switzerland is the fiefdom of the ancient banking dynasties, look at their flag, what does that look like? Where did that symbol come from? What is that related to? What else does that flag grant people?(entry into any country in the world and a global network of logistics and support - \"the red cross\" - a permanent \"observer\" status at the UN). Why are they neutral in every conflict yet extremely well-armed and trained as a society? How do they make it so everyone sends them their money?\n\nIt's a place that's part of something greater that has happened throughout world history and commercial history. It's a sovereign state controlled by bankers, for bankers. The bankers don't enter the conflicts(they merely fund and payroll both sides) so no one will ever enter the country and seize the funds held there because the people in power on both sides have their personal funds held there, and the Swiss claim neutrality. It's a stable place in Europe based on ancient treaties and banking dynasties/sovereign military orders, so they can make their own laws and hold their own without being interfered with by external legal or military entities.\n\nLet's say it's just a place that has been run by smarter people than most places have been for a longer period of time.",
"Huguenots (French Protestants) escaping persecution in France came to Switzerland and basically created modern banking there in the 17th century. Most industries that have a long unbroken history built up through generations of continued development are almost always leaders in whatever sector they find themselves in. \n\nThat is, it's no accident that the Swiss banking sector is as successful or respected as it is. ",
"Confidentiality and neutrality, coupled with legitimacy. It's extremely difficult and time-consuming for foreign (non-Swiss) government investigations to actually ferret out a paper trail with regards to the contents of your Swiss bank account, and there's very little that they can do to freeze it: they would need evidence of wrongdoing that is normally almost impossible to attain without the very information that they're trying to acquire through the banks. Meanwhile, so many legitimate enterprises use the Swiss banking system--including said foreign governments--that nobody wants to simply go after them and force them to change the way they do business. ",
"It's not. In case you hadn't heard, the Swiss have *negative* interest rates. That's right, the bank charges you to keep your money there.",
"I'm living and working in Switzerland.\nOne update to what's already in the topic.\n\nIf you hold US passport, it's now damn difficult to open even simple current account for salary (if you're US citizen working in CH).\n\n\nAnd don't forget, that from certain amount, interest is negative. You have to pay money to save them in Switzerland.",
"Swiss lawyer here: Until recent years swiss banks were not allowed to give away any kind of informations considering bank accounts, no matter what.",
"It means nothing to an American nothing now. The Swiss don't accept new US customers, and are throwing out existing customers because they don't want to deal with US regulations. It used to be a safe place to park money with no questions asked. Not anymore.",
"Swiss economy is very stable. So it is very safe to keep money in Swiss Bank, especially for the rich. They securely store billions of dollars in Swiss bank. As they are a stable economy, there is no chance that there will be a bankruptcy or something like recession affecting Swiss Bank.\nThe privacy is also very high. You can't just withdraw your cash. You need to show your passport and other documents to prove that 'you are you'. This lets the rich to hide their money and evade tax in their native countries.",
"\"Name-less\" bank accounts are the holy grail of tax evasion. If you can deposit money in there and not have it traced back to your identity, you can essentially live a tax-free life. The hard part is wiping away the finger prints to your identity. You essentially could do this in Switzerland, Bermuda and certain other jurisdictions until recently when governing bodies believed it would be in their best interests to disclose the information."
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6dnu84 | how do farmers make sure that no fertilized/developing eggs make it to market? | I assume hens and roosters aren't put together, but especially for free range, I'm sure at some point a rooster and hen must have found a way to get frisky | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6dnu84/eli5_how_do_farmers_make_sure_that_no/ | {
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"Eggs can only get fertilized when there are roosters around to fertilize the eggs. No roosters, no fertilized eggs. So the way farmers make sure that no fertilized eggs get to the market is by separating them from the chickens.\n\nNow the tricky thing here is that farmers also need fertilized eggs to grow new chickens to replace to older ones. Half of the chicks born are female, whereas the other halve are males. This isn't so much a problem for the chickens that are grown for meat consumption (both are eaten). However, roosters are useless for the production of eggs. So most roosters are killed early on.",
"Most egg processors \"candle\" each egg, shining a bright light through it. If there is something growing, it's not sold. Roosters aren't common at egg farms, as chicks are sexed early in life and the boys that live are destined to be part of the meat cycle.",
"Most hens are not raised near roosters. Even free range. But they do check the eggs. They do so with a method called candling. This is where you shine a light through the egg and look for the embryo. In olden days this was done with an candle by eye (thus the name). In modernity it is done with bright electric lights and cameras in an automated process. It is possible that some get through, but even that is not an issue since eggs are washed and chilled quickly after being harvested which stops development. ",
"They separate the roosters from the hens when old enough to determine sex of chick... a pen of egg laying chickens won't have any roosters.",
"I worked for a turkey producers and visiting the hatchery was fascinating. \n\nThe sexers look at the vents of the poults and determine, with a 98% success rate, whether it's a stag or hen and throw it into a chute. Depending on what the farms are placing depends on what sex is more desirable. But it was usually Hens that were needed more. \n\n50k poults could be hatched per day and there was pretty even split of male/female. 52/48% I believe. Every time. \n\nThe unwanted, deformed, dead in shell poults then go off to the gas stunner and then to the IMD (Instant Mechanical Destruction) \n\nIt's brutal. "
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1a4ce8 | If Iridium is apparently not the heaviest atom found in nature, than what accounts for for a chunk of pure iridium being the densest substance on Earth? | askscience | http://www.reddit.com/r/askscience/comments/1a4ce8/if_iridium_is_apparently_not_the_heaviest_atom/ | {
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"Like platinum and gold, iridium is a noble metal. This means it does not react with air or soil and forms nuggets.\n\n\nThe noble metal osmium (by some sources) is slightly denser and is also found as an uncombined element.\n\nOsimium and iridium are also the densest elements period. The reason for this is due to lathanide contraction, a result of poor shielding of nuclear charge (nuclear attractive force on electrons) by 4f electrons; the 6s electrons are drawn towards the nucleus which lowers atomic radius size. \n\n_URL_0_\n\nWe can go on to infer that if there were stable post-actinide elements then the pure crystals of these would be far more dense (ie: 40 gcm^-3 for Hassium)."
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16q17m | what does java do for the computer? | With the problems with having to disable it, I'm just wondering. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/16q17m/what_does_java_do_for_the_computer/ | {
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"Java is an environment that programs can run in, kinda like Flash Player.\n\nWithout Flash Player, you cannot watch Flash animations or play Flash games. Similarly, without Java, you can't play Java games or use Java programs. (Minecraft is a Java program.)",
"The big thing about java is that it is a language that lets you run the same program on multiple OSs. You know how you can't take a Windows program and run it on a Mac? Well, you usually can if it is developed in Java. The java client on your computer allows it to run the java code and converts it so your PC can run it so they just need different client versions for the different operating systems."
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2d2zwp | how do small particles actually move? | So I know that we can predict the amount of chance a particle has to be at a certain place by solving the schrodinger equation for the whole system. But in order for the particle to behave correctly and not violate our solution, wouldn't it have to 'know' the whole system as well? instantaneously?
(This really confused me while trying to study for my first exam quantum physics)
| askscience | http://www.reddit.com/r/askscience/comments/2d2zwp/how_do_small_particles_actually_move/ | {
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"There isn't a thing that is \"the particle,\" separate from the wavefunction. People often say things like \"the wavefunction gives the probability that the particle will be detected at a certain point\" but what that really means is that the wavefunction gives the probability that another wavefunction (that of the detector) will react as if it experienced an interaction at that point.\n\nNow, you might wonder why the same wavefunction can't \"interact\" at two points simultaneously. That's a bit of a philosophical mystery. Quantum field theory can go somewhat toward explaining it, but still, there are weird things happening that look a lot like faster-than-light travel, or omniscient knowledge of the whole system, or whatever. It turns out (if you examine this in QFT) that the faster-than-light rule is modified so that it doesn't quite apply to wavefunction collapse."
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33c1tj | Is there a reason for radioactive decay to emit only alpha particles as protons and neutrons combination? | I was wondering why there is no emission of another protons and neutrons combinations (eg. deuterium nucleus). I'm aware of proton, neutron and beta decay but I'm asking specifically about nucleus-like particles. Maybe there is but it's so unlikely that it is of no interest to physics? | askscience | http://www.reddit.com/r/askscience/comments/33c1tj/is_there_a_reason_for_radioactive_decay_to_emit/ | {
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"It's because an alpha particle has a very high binding energy per nucleon compared to other nuclei in this region.\n\n[Check out that sexy spike in binding energy at 4He.](_URL_0_)\n\nFormation of the alpha particle must occur within the mother nucleus prior to emission, and the high binding energy makes it for possible to this to happen. (Note that this is a simplistic explanation of what's going on. An in depth discussion of alpha decay requires a full quantum mechanical treatment, and is beyond my knowledge).\n\nOther, heavier particle emissions can occur. In 1984 223Ra was observed to undergo 14C emission.\n\n_URL_1_\n\nAccording to that reference the 223Ra nucleus is still about a billion times more likely to undergo alpha decay than than 14C decay.\n\nSince then other cases of 14C emission have been observed, as well as emission of 24Ne and 28Mg nuclei.\n\n_URL_2_\n\nEdit: formatting"
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qxadu | - xkcd comic #1028 | I don't really understand [it](_URL_0_). Does this mean I'm bad at communicating information to others, or understanding pictorial array's attempts at communicating? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/qxadu/eli5_xkcd_comic_1028/ | {
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"White hat sees a dangerous trench, tries to warn others verbally. \n\nShort Hair and Woman don't understand (or at least don't pay attention to) the danger until they experience it for themselves by falling in the trench.\n\nMeanwhile, Woman's seen a similar danger in the other direction; she tries to warn White Hat, who is too busy assuming Woman will warn Short Hair about the first trench to pay any attention, and falls in the second trench.\n\nWhen Beret sees the danger, rather than simply telling No Hat about it, he takes him and shows him first-hand; No Hat understands immediately.",
"Just gonna throw this out there for future reference: _URL_0_",
"Panel 1 - Hat Guy sees a hole in the ground. \nPanels 2, 3, 4 - Hat Guy tells Hair Guy. Hair Guy doesn't understand, and Hat Guy gives up trying to explain. \nPanels 5, 6 - Hat Guy tells Girl about Hair Guy not understanding him. Girl tells Hat Guy about a different hole in the ground. Neither of them understand one another. \nPanels 7, 8, 9 - Hair Guy and Girl encounter one another. They tell each other about Hat Guy, and walk off. \nPanels 10, 11 - Hair Guy and Girl are too busy thinking and talking about Hat Guy that they fall down the hole that Hat Guy was trying to warn them about in the first place. And at the same time - \nPanel 12 - Hat Guy falls down the other hole that Girl was trying to warn him about. \n\nMeanwhile -\n\nPanel 13 - Beret Guy sees the hole in the ground. \nPanel 14, 15, 16 - Beret Guy encounters No Hair Guy, and asks him to follow back to where the hole is. \nPanels 17, 18 - Beret Guy *shows* No Hair Guy the hole. They leave both knowing about the hole. \n\nMoral of the story - show, don't tell.\n"
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3qdqsz | Is there a mental disorder that causes the delusion of having other mental disorders? | The delusions would be of experiencing symptoms of other disorders. Someone may claim to suffer from schizophrenia, show no symptoms of it, yet claim to experience many or all of the non-observable symptoms.
I am not referring to factitious disorders, where the individual is intentionally spreading lies. | askscience | https://www.reddit.com/r/askscience/comments/3qdqsz/is_there_a_mental_disorder_that_causes_the/ | {
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"Delusions occur as a symptom of several different known mental disorders-- most commonly schizophrenia, but also delusional disorder, schizoaffective disorder, manic episodes (part of bipolar disorder), and sometimes depression or neurocognitive disorders such as dementia. Delusions involve a very strong belief that is resistant to evidence contrary to the belief. The content of delusions ranges widely (e.g., paranoia, grandeur, somatic, etc).\n\nThere is no disorder that *specifically* causes individuals to have delusions about having another mental disorder. However, it is theoretically possible for a delusion to cause a belief that one has a particular mental disorder. If this did occur, it would probably be easy for a psychologist to determine that it was a delusion for multiple reasons. Firstly, unless the person memorized the DSM criteria for the disorder and that somehow became part of the delusion, they would probably misrepresent the disorder. Secondly, it would probably become apparent that the person suffers from delusions because of other symptoms they exhibit (particularly if the delusions are a symptom of schizophrenia).",
"Hypochondria would be the general term. [Munchausen syndrome](_URL_0_) may be another example. I suppose psychosomatic disorders might qualify as well.\n\nEdit: just noticed the part about factitious disorders, so Munchausen wouldn't qualify."
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803vxi | why do you feel unsafe when limbs are sticking out under your blankets? | And why does this not apply to your head? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/803vxi/eli5_why_do_you_feel_unsafe_when_limbs_are/ | {
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"I’m not a psychologist but I imagine it has to do with feeling exposed. When you sleep you’re at your most vulnerable so I think the body is trying to protect itself as best as possible before falling asleep. It’s that or because my parents let me watch Jurassic Park when I was too young and the velociraptors are still out to get me. ",
"So far all the answers are wrong. You don't feel unsafe. What you feel is that something is different. You've forever slept with feet under covers then you try to sleep with them out and it interrupts your sleep. It's the same if for a long time you haven't been chewed on by a velociraptor and now you're being chewed on. Can't tell if its bad or not but better run just in case.\n\nTo see how this works try sleeping with kitchen gloves on. You'll have trouble sleeping for 3 days then it will seem normal and you'll sleep just fine.\n\nTo see how this works add a new sleep partner that tosses and turns. It's sleepless misery for the first 3 nights then it seems normal.\n\nTo see how this works stick your feet out on a hot night. You'll have trouble sleeping for the first 3 nights. Then you'll sleep no different feet in or out.\n"
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btlasz | How did ancient people develop martial arts? | When i say martial arts, i am talking about fighting styles with an organised syllabus and distinct style, from ancient Japanese peasants to European warrior man at arms. How did they develop effective techniques and whst would influence the differences in one style from another? For example, the fighting style of japanese ninjas to mongolians thst could wrestle? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/btlasz/how_did_ancient_people_develop_martial_arts/ | {
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"We don't know how the earliest martial arts styles developed. For later martial arts, there tend to be three types of origin stories:\n\n1. Divine inspiration. For example, received the techniques in a dream or vision, in a flash of enlightenment while praying, or being taught by god(s) or other supernatural beings (e.g., tengu).\n\n2. Development of the new style during a period of solo study. This includes tales such as watching animals fighting and adapting those techniques to the human body, solo training in the mountains as a hermit, etc.\n\n3. Learning one or more existing martial arts styles, and combining them or improving techniques in them.\n\nThe first two usually include prior experience in martial arts, and thus elements of 2 or more of these stories are often combined. The last type cannot explain how the first martial arts styles developed, and, realistically, neither can the second - the first martial arts styles (\"with an organised syllabus and distinct style\") would have developed from pre-existing techniques, with the new part being an organised syllabus.\n\nHow formal the syllabus is affects what is recognised as a style. Whether or not those who train under the founder of the style go on to teach their students the same style, and call it the same style, affects what is recognised as a style. For example, we see a variety of styles in boxing, but these are (usually) devoid of formal syllabi that distinguish between them - different coaches teach to the same formal syllabus, and the differences in what they teach are informal. Thus, the styles don't have the same recognition or persistence that we see in, e.g., karate or kung fu - each coach has their own individual style.\n\n > How did they develop effective techniques\n\nTraining and experimentation.\n\nTake two children, give them sticks, and tell them to fight each other, and they will learn techniques (play can be training). The most basic techniques are very natural - untrained people can punch, slap, kick, grapple, and hit each with sticks. These things don't need to be rediscovered. What needs to be developed is how to do these things well. Training (whether play or deliberate) that includes a level of competition motivates improvement. If one member of the group develops an improvement, the others can learn it, and it spreads through the group.\n\nA playful environment (which can still be present in serious training) affords the opportunity to experiment. People can try things, different things, and see what works.\n\n > and whst would influence the differences in one style from another?\n\nReal differences in styles can result from:\n\n1. Weapons. At the most obvious level, wrestling is different from archery which is different from swordsmanship. Similar weapons tend to result in similar martial arts. For example, there are many similarities between Japanese swordsmanship using the katana and Medieval European swordsmanship using the two-handed (or, if you prefer, hand-and-a-half) longsword. Differences between similar weapons can result in significant differences - for example, the Japanese katana is shorter than the European longsword and single-edged and curved, and some techniques differ as a result.\n\n2. Rules. The major old unarmed martial arts are sports-oriented - they are mostly wrestling. Typically, there is a method of obtaining victory that is far short of killing or even incapacitating the opponent (e.g., throwing, pinning), and this greatly influences the style. Modern boxing differs from Kyokushin karate because boxing rules don't allow kicks or throws, and Kyokushin doesn't allow punches to the face (among other differences). Where rules are similar, fighters from different styles will usually fight in very similar ways. We can call this \"the kickboxer effect\", and it suggests that different styles are more different ways of learning how to fight than different ways of actually fighting.\n\n3. Chance. As different groups train and experiment, and develop new techniques, their body of techniques will develop differently. For many things, the differences are minor, but in some cases, bigger differences arise. For example, some styles use a hook punch with a horizontal fist striking with the first two knuckles while others use a vertical punch striking with the last three knuckles (and the same for straight punches, too).\n\nWe can also add:\n\n* Deliberate changes to make a new style difference from another (or simply to have a \"secret technique\" that can be taught to paying students).\n\nThis doesn't always result in real differences. Sometimes, two styles can be distinguished from each other only by their names - their techniques are identical! Sometimes, the only difference between two styles is their kata/forms/patterns while their body of techniques remains identical.\n\nThe evolution of taekwondo shows a succession of changes. Initially, the only difference was the name (and the use of Korean language in teaching and for naming techniques, but this difference was present while the art was still considered \"karate\"). Next, an emphasis on spectacular techniques (such as jumping spinning kicks) was added, largely for marketing purposes, but also to make taekwondo a little different. Later, the Japanese karate kata (which were still being used in taekwondo into the 1960s) were replaced by a new set of patterns. At this stage, the base of technique was still essentially the same as that of Shotokan karate. Later, the WTF (now WT) competition rules (used for Olympic TKD) drove changes in technique, and modern Olympic taekwondo competition looks very little like the ancestral art.\n\nA simplified story - martial arts other than Shotokan, including other Japanese karate styles and Chinese styles - influenced TKD, and TKD itself has a diverse range of styles, some with more influence from those other arts. The above story is the evolution of the predominant style. For further reading on this, see Alex Gillis, *A Killing Art: The Untold History of Tae Kwon Do*, ECW Press, 2011."
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1hq6hd | The Limitations of the Huygens-Fresnel Principle in Wave Propagation | I recently learned about the Huygens-Fresnel principle while studying Physics in high-school. However, there were several points that bothered me. I have tried to research these questions, but nothing has come up to sate my curiosity.
For reference: _URL_1_
Questions:
1) From my understanding, the propagation of the wave is a result of the overlap between the spherical waves which surround a point on a part of the wave. In this case, why does the propagation only travel outwards? Why doesn't it travels inwards or "backwards" so to speak back towards the slit?
2) According to the principle, the propagation of the wave should be propagated in the outward direction, but it should also always touch the barrier of the slit, kind of like this:
_URL_0_
In most diagrams and reality, however, the sides of the propagated wave start to taper off? Why does that happen?
Thanks in advance! | askscience | http://www.reddit.com/r/askscience/comments/1hq6hd/the_limitations_of_the_huygensfresnel_principle/ | {
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"To understand shadows, consider this: The waves to the right of the slit (if the wave is traveling right) are the result of the sum of the waves from the points in the slit. If you go straight out from the center of the slit, consider all the waves you'd get from each point: the waves from the center of the slit reach you first, followed shortly by the waves from the edges. If the difference in those two travel times is low enough, you'll get all the waves arriving at the same point in their cycle and adding constructively. So the wave keeps traveling perpendicular to the slit without much trouble. \n\nBut with your point off to the side, things are different. Each point from the slit is still contributing, but now instead of being roughly equidistant to the point in question, there are a range of phases contributing (since each wave took a different amount of time to arrive despite being in phase with each other initially). If there's enough difference (if the period of the wave is short enough to be comparable to the difference in travel time), then there will be waves which are at opposite points in their cycles and canceling each other out, leaving a shadow of low amplitude. You can also see that the shadowing effect depends on both the wavelength and the width of the slit, because the wavelength determines the wave period and the width of the slit determines how different the travel times will be. \n\nThanks for prompting me to think about this, I actually found out why the wavelength hitting a slit matters, in terms of Huygen's principle :)\n\nRegarding the travel direction of the waves, it's a bit subtle. The waves obey the [wave equation](_URL_1_), which basically says that the vertical acceleration of any point on the lake is proportional to the curvature (second derivative) at that point (with water in a lake you can think of this as low points being filled in and high points dropping). Every solution of this equation happens to be the sum of an outgoing and incoming wave for each point on the lake. Also, the sum of any two waves which are solutions to the equation produce another solution, which is why waves can be superposed without bumping into each other (and this is the basis of Huygen's principle) When you consider a point to be a \"source\" (for the purposes of the Huygens principle), all you're doing is specifying the amplitude of that point at that instant. \n\nWhat happens to the incoming waves at that instant? They actually pass through that point and become outgoing waves. the outgoing waves keep spreading until they hit some kind of boundary that doesn't follow the wave equation. [This gif](_URL_0_) shows a traveling wave. Knowing the rule for acceleration of each point, you can work out why each point behaves as it does (I'll describe the right-moving wave). On the front end of the wave, there is some positive curvature (curving upwards away from the point) and so that point is accelerated upward (the next moment this creates more curvature for the point to its right). A ways up there is a point where the wave goes from being curved up to being curved down. This is the point where there is no acceleration and the point has reached its maximum upward speed. At the top, the curvature is negative and the point slows down and turns back around. As it nears the edge the positive curvature pushes up again, slowing it down, until it reaches zero once again and the wave has passed. This illustrates how a wave travels in obedience of the wave equation, and why it doesn't change direction until it hits something."
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7hnj21 | Why haven't we deciphered Indus Valley Civilization script yet or are we any closer? | One might think that with huge advancement in computation technology, we should be much closer at deciphering it. Is there any serious work still going on this or there is a lack of interest or this particular subject is lacking funds? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/7hnj21/why_havent_we_deciphered_indus_valley/ | {
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"You might also try /r/AskAnthropology",
"#What do you need to decipher a script?\n\nIn order to successfully decipher a writing system, you must understand the language(s) written with that writing system. Most successful decipherments are based on bilingual or trilingual inscriptions and/or knowledge of the underlying language(s). \n\nBeginning with an example of the latter, the successful decipherment of Linear B began with Alice Kober, who compiled over 180,000 attestations of signs, created frequency lists of signs, and noted their positions (word initial, final, or medial). Kober noted that the first two syllabic signs often stayed the sign, whereas the final signs changed, indicating an inflected language. Linear B was finally cracked by Michael Ventris, who used phonetic values from the already deciphered Cypriot syllabary to analyze Linear B inscriptions. When he substituted the known phonetic values, he immediately recognized familiar place names like Ko-no-so (Knossos) and A-mi-ni-so (Amnisos). Correctly identifying the language as (Mycenaean) Greek, Ventris and his classicist collaborator John Chadwick were able to figure out words known from later Greek dialects. For example, a-ku-ro corresponds to Greek ἄργυρος (\"silver\") and pa-te is instantly recognizable as Greek πατήρ (\"father\"). \n\nThe decipherment of cuneiform, on the other hand, required a multilingual inscription, since Akkadian was not a known language. Historians in the 17th century realized that two scripts were used at the site of Persepolis in Iran for monumental inscriptions, what we now call cuneiform and Old Persian cuneiform. In 1778, Carsten Niebuhr realized that some of the inscriptions at Persepolis were written in three styles of cuneiform, one of which was alphabetic. Based on copies of inscriptions, Georg Grotefund, a Greek teacher in Germany, began to decipher the Old Persian inscriptions. Figuring out that the inscriptions contained the names of kings as well as words like \"king\" and \"son,\" Grotefund began using the known names of Persian rulers to decipher Old Persian cuneiform. Ultimately, however, the inscriptions did not vary enough to provide sufficient vocabulary. The next stage in the decipherment of cuneiform began with the copying of the Behistun inscription, a very lengthy trilingual inscription written in Akkadian, Elamite, and Old Persian. With this wealth of new information, along with knowledge of later stages of Persian, the decipherment of Old Persian was completed. With the Behistun trilingual in hand, scholars began to tackle the Akkadian text, beginning with the identification of Akkadian anaku (written as a-na-ku), the first person singular personal pronoun \"I.\" The decipherment of Akkadian was a somewhat lengthy process that needn't concern us here, but suffice it to say that knowledge of other Semitic languages helped a great deal in the decipherment. By the 1850s, cuneiform had been more or less deciphered.\n\nUnfortunately, there are several writing systems where the language is unknown **and** there are no multilingual inscriptions. The Indus script is one example; Linear A is another. These are still undeciphered and will likely remain so in the absence of lengthy inscriptions and/or bilingual inscriptions. \n\n#Complicating factors\n\nWriting systems are easiest to decipher when the corpus is extremely large with lengthy inscriptions. The corpus of IVC inscriptions is fairly large (around 4000), but most are extremely short, consisting of about 5 signs on average. The longest inscription has only 26 signs, which is quite short indeed compared to inscriptions of the ancient Near East. Moreover, about half of the corpus consists of duplicate inscriptions, which considerably reduces the amount of material decipherers have to work with. In other words, we have the following problems preventing the successful decipherment of the IVC script:\n\n* The language(s) that used the IVS writing system are unknown.\n\n* The corpus of discrete inscriptions is not very large.\n\n* Almost all inscriptions are extremely short.\n\n* No bilingual or multilingual inscriptions have been found.\n \n#Establishing the basics: directionality and type of writing system\n\nIn order to decipher a writing system, one must determine the direction in which texts are read and the type of writing system (i.e. alphabetic, logosyllabic, etc.). \nThe directionality of writing is fairly easy to determine. If a text has signs that align neatly with the right edge of the writing surface but don’t quite meet the left edge on each line, it’s probably written right to left. Likewise, if signs begin neatly on the right edge but become squished and close together as one approaches the left edge, the text was probably written right to left. Incidentally, right to left is the normal direction of Indus writing, although there are some examples of left-to-right writing as well as a very small number of boustrophedon inscriptions. \n\nClassifying a writing system requires creating a comprehensive and accurate list of attested signs. If the number of signs is relatively small, perhaps two or three dozen, you’re dealing with an alphabetic script. Examples include Old Persian cuneiform (36 phonetic signs) and Ugaritic cuneiform (30 phonetic signs). If you have several hundred signs, you’re probably dealing with a logosyllabic writing system like cuneiform and Maya glyphs. \n\nEstablishing the number of signs in the IVC script has not been easy. For one, different scribes tend to write signs a little differently, making it more difficult to determine whether two similar signs are the same sign or subtly different signs. Furthermore, the IVC script - like many others - has allographs, different versions of the same sign. For example, someone trying to decipher our alphabet may immediately recognize lower and upper case x/X, z/Z, and k/K as the same letters, but he may mistakenly classify r/R, g/G, t/T, and l/L as eight distinct signs. This is one area in which technology helps quite a bit. Reflectance Transformation Imaging (RTI) is extremely useful for picking out tiny details in inscriptions, a vast improvement over raking light photography or a bare eye and magnifying glass.\n\nThe current estimate, based on the work of Asko Parpola, is around 425 signs, so the IVC script is probably logosyllabic. \n\n#What advancements have been made in decipherment?\n\nDetermining word boundaries is the first step. While some writing systems have convenient word dividers, others have continuous writing with no division of words (*scriptio continua*). There are no clear word dividers in the IVC writing system, so decipherers have had to identify probably word breaks based on “pairwise frequencies,” the number of times two signs are attested next to one another. In English, for example, the letters -t-e-d or -i-n-g often mark the end of a word. If you see the sequence xxxx-i-n-g-r-e-xxxx, you’d probably guess that the words are divided between the -g- and -r-. \n\nDecipherers have since moved to identifying affixes in the writing system (prefixes and suffixes) using a system much like Kober’s for Linear B. Two probable affixes have been identified, the fourth and fifth signs in [this sign chart](_URL_0_). Parpola also noticed that these signs could be ligatured with an additional sign to form new signs. Guessing that this was a plural marker, Parpola proposed that the suffixes were case markers. Since the inscriptions are all so short, they are probably either dative (to/for Person X) or genitive (of Person X) singular and plural constructions. New discoveries proved this hypothesis incorrect, as the two suffixes were sometimes found next to one another, but most people agree that they are inflectional markers of some sort, perhaps gender. \n\nIn addition to the recent work on affixes, there have been tentative “decipherments” of particular signs. Taking as his point of departure the likelihood of a Dravidian language lurking behind the IVC writing system, Henry Heras noted that one of the most frequently attested signs is a fish sign. The word for “fish” in Dravidian languages is *mīn*, which is also often the word for “star.” Stars are often identified with divinities, so Heras proposed that the fish is a component of theophoric names, which are common in India. Expanding on Heras’ work, Parpola has proposed an astronomical reading of the fish sign, in which numbers associated with the fish sign indicate clusters of three, six, and seven stars, which refer to constellations. This remains, however, purely speculation.\n\nAs another example of \"decipherment\", Parpola identifying an overlapping circles sign as a logographic writing of “bangle” and gave it the phonetic reading *muruku*. This is quite similar to Murukan, the name of a war and love god, and the same sign may have been used for both.\n\nDecipherment of the IVC writing system in continuing in this vein. As you can see, the decipherment of the IVC writing system is still in its infancy and will likely remain so until lengthy inscriptions have been recovered - and preferably at least one bilingual inscription. Inscriptions in Mesopotamia indicate translators were associated with the trade between Sumer, the lands of the Gulf, and the Indus Valley, so the new excavations in the Gulf region may uncover a bilingual inscription holding the key to decipherment. \n\n#Sources and further reading:\n\nMahadevan, I. (1989). What do we know about the Indus script? Neti neti ('not this nor that'). *Journal of the Institute of Asian Studies*, 7: 1-29.\n\nParpola, Asko (1994). *Deciphering the Indus Script*. Cambridge: Cambridge University Press.\n\nPossehl, Gregory (1996). *Indus Age: The Writing System*. Philadelphia: University of Pennsylvania Press. \n\nRobinson, Andrew (2007). *The Story of Writing: Alphabets, Hieroglyphs & Pictograms*. New York: Thames & Hudson."
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51f9fj | When a byzantine emperor would choose a patriarch, would the patriarch give personal advise to the emperor? | This was always something I inferred from my reading of history. I know the Eastern Orthodox have a tradition of "spiritual fathers". But was this the case? How would the emperor decide whom to choose? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/51f9fj/when_a_byzantine_emperor_would_choose_a_patriarch/ | {
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"I can answer in the case of one patriarch of Constantinople: Nestorius. Firstly, how was Nestorius chosen? His election came in the midst of a controversy over whom to elect to the position and his election was that of an outside candidate, so as not to give in to one of two factions in the city. He was at the time a monk at the monastery of Euprepius, trained in the Antiochene tradition. He was selected by the Emperor and installed in 428 as the Patriarch of Constantinople. To let you know just how much power this wielded, at least within the city walls, within five days of Nestorius' election he sent a police force to an Arian chapel (which was illicit, but there were places in the Empire where the laws were pretty lax) to destroy it. The Arians decided not to go down without a fight, so they set their own chapel ablaze! The police were not ready for this and the fire ended up burning down several buildings in that quarter of the city. \n\nThis sort of civic privilege continues in the Empire through the early and late Byzantine periods. \n\n\nLouis Duchesne, *Early History of the Christian Church From Its Foundation to the End of the Fifth Century. Vol. 3, The Fifth Century.* trans. Claude Jenkins. New York: Longmans, Green and Co. 1924: 219. \n\nSocrates, *Ecclesiastical History* 7.32. "
]
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46ij7l | I've heard the Soviets were victorious in WWII because they were willing to lose as many men as necessary to win battles. Is this true? | The way I've heard it, the Soviets basically were okay with shoving their men into a meat grinder during battle as long as they got an eventual victory. The Germans were not willing to throw away their soldiers' lives so easily, and this was one of the reasons the Soviet juggernaut was able to muscle its way through German defenses and straight into Berlin.
How accurate is this? If true, how significant was this "win at any cost" mentality in the grand scheme of things? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/46ij7l/ive_heard_the_soviets_were_victorious_in_wwii/ | {
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"Yes and no. \n\nJosef Stalin was certainly OK with losing as many men as necessary-I don't know how it is possible for the mildly historically cognizant to come to any other conclusion. The man just did not value human life, period, and it amply showed during episodes like the \"Rzhev Meat Grinder\" of 1942, a case where the Soviets did essentially do what you described. However, so was Adolf Hitler. The first of the two dictators to issue a \"Stand or Die\" order (and enforce it, brutally albeit successfully, during the retreat from Moscow) and use punishment battalions was Hitler, not Stalin. He was every bit as fine with throwing away the lives of his soldiers as Stalin-the Germans did not lose for a lack of squeamishness on Hitler's part. Stalin himself noted that he took these ideas, that he would use during Stalingrad, from the Germans in one of his 1942 speeches. \n\nAnd this also underestimates the tactical skill of many Red Army commanders, men like Chuikov and Rokossovsky. The Stavka showed strong finesse as the war went on. Nowhere was Red Army skill more specularly on display than in Operation Bagration, where they used deception and a Soviet style of Blitzkrieg that emphasized wider rather than narrow attacks. The Soviet victories over the Japanese before the war also showed some of the skill of the Red Army. While the Red Army was far from perfect, as seen in the Winter War and much of the early fighting against the Germans, they could hold their own on more than just numbers.",
"I feel /u/Georgy_K_Zhukov put together a pretty good series of comments on this subject in this thread:\n\n_URL_0_"
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3jnnqx | why is there so many muslims in indonesia, malaysia ... ? | Edit : My question may seems a bit racist for some of you but I am not. I thought it would have been more logical for these countries to be animist or buddhist. I don't have any problem with muslims and people from there ! I just wanted to understand why that's it. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3jnnqx/eli5why_is_there_so_many_muslims_in_indonesia/ | {
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"Back in the day the Indian Ocean was host to a lot of trade (for the time). Monsoon winds helped reliably carry trade from as far as China to East Africa. \n\nA lot of the trade came to be dominated by Muslim merchants. In much the same way that West African kings and merchants began converting to Islam to share a religious ties with their Arab trade partners, some rulers and wealthy traders in what is, today, Indonesia and Malaysia (and Brunei and some other places) converted to Islam. \n\nIslam grew slowly in the region over centuries, but it was always primarily due to trade links to Islamic polities on the Indian subcontinent and Arabia."
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20to0k | What was the reaction to Polish territories being annexed by the Soviet Union in 1945? | Hello everybody,
This is a question that has been on my mind for quite some time. The Wikipedia article goes into some detail about the [Oder-Neisse line](_URL_1_), but doesn't really cover the other transfer of territory that took place. I'm referring to the territory annexed by the Soviet Union as seen on [this map](_URL_0_). The amount of land transferred, along with how this redefined Poland, was huge. Furthermore if I am not mistaken, there were areas transferred where the majority of the population was Polish. So what was the reaction (both inside and outside Poland) to such a big change?
Many thanks in advance for your replies. | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/20to0k/what_was_the_reaction_to_polish_territories_being/ | {
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"text": [
"The legitimate government of Poland, the Polish Government in Exile based in London. Was staunchly opposed to the annexation of Eastern Poland and the willingness of the Western allied powers to allow the Soviets to get away with it. The British government, specifically Winston Churchill was opposed to it, until the Yalta conference where it was agreed to make the Curzon Line the eastern border of Poland. Unfortunately, the Polish government in exile's protests meant very little. The Western allies were in no position to force the Soviets to relinquish eastern Poland, the Polish Government in Exile had their authority and legitimacy challenged by the provisional government for Poland set up by the Soviets, and the Polish Home Army ( a huge, anti communist, partisan group) were decimated in the Warsaw uprising, and by advancing Soviet troops. Without the Home Army there was no serious opposition to the Communist Polish government. \n\nAlso, its worth nothing that many of the lands east of the Curzon Line had been taken by the Poles in the Polish-Soviet war. And that while many of the cities were filled with Poles many areas and much of the countryside was not a Polish majority.\n\nEdit: Partisan is a better term than rebel."
]
} | [] | [
"https://en.wikipedia.org/wiki/File:Curzon_line_en.svg",
"https://en.wikipedia.org/wiki/Oder%E2%80%93Neisse_line"
] | [
[]
] |
|
1m7gkq | If 1 of the heads of a Siamese Twin was to be choked/cut-off, would the other "head" die? | So, we're having this discussion, and we're wondering - if you have a person who is a Siamese twin with two heads, and one of the heads gets choked or cut off, what would happen to the other head? Would they die? Would they be completely fine? | askscience | http://www.reddit.com/r/askscience/comments/1m7gkq/if_1_of_the_heads_of_a_siamese_twin_was_to_be/ | {
"a_id": [
"cc6jx2k",
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"text": [
"I'm not particularly qualified to answer this question, but I believe it would depend simply on the degree to which they were conjoined. Conjoined twins can be two wholly separate humans, only conjoined by a small area, such as sharing a leg or an arm, or can be highly conjoined, sharing one or more vital organs. Obviously there's a vast difference between a twin who shares a leg with the other dying compared to one who shares a heart or lungs.\n",
"Every Siamese twin is different, there are no rules or sure things.\n\nIf they both had pathways to the lungs, then assuming one could supply enough oxygen for both, getting one airway blocked via choking would not be a problem. \n\nIf you are taking about choking like cutting off blood flow to one brain, then there would be brain damage, and depending upon how the systems were wired up, might have an effect or not. \n\nIf all the systems have strong connections and can be supported by a single brain, then not much else would happen.\n\nGetting cut off again would depend completely on the specific pair of twins. Assuming the other brain can support the body, then it shouldn't be much different than getting a leg cut off.... high possibility of bleeding out, but in a hospital there is a chance to be ok.\n\nIf one was choked out to the point of the tissue dying, then it would have to be removed or would get necrotic and would be life threatening, but again assuming medical care and that the other brain can handle entire body, no worries."
]
} | [] | [] | [
[],
[]
] |
|
bglqtz | why are some gun calibers stronger than others, yet going by name 7.62mm is weaker than .338? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bglqtz/eli5_why_are_some_gun_calibers_stronger_than/ | {
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"text": [
"The caliber refers to the size of the projectile, not the amount of powder used to propel that projectile.",
"Different calibers use different amounts of powder and different weights of bullets. 7.62 is a metric measurement that equals .308 in inches compared to .338.",
"The naming of ammunition doesn't give you all the relevant information about a round. Most of them are simply named based on the caliber - the diameter of the bullet. That doesn't tell you anything about the length/mass of the bullet or how big the powder load is.\n\nUltimately, if you want to understand these things, you just need to look them up & memorize them - there's no real logic behind a .22LR being a child's plinking round while a .223 Remington is the round of choice for the US military.",
"You've only listed diameter. That's about as helpful as listing the length of a car and trying to estimate its speed. You've basically said \"I've got a 3 meter long open wheel car and a 3.4 meter long open wheel car, why does the 3.4 meter long one go faster?\" You've missed that one is a GoKart powered by a lawnmower engine and the other is an Ariel Atom with a V8 engine in the back.\n\nYou need three dimensions of a cartridge(bullet+case/powder) to estimate its power. The diameter of the round is one of them, but without knowing how long the case is and how large of a diameter the case is you have no idea how much gunpowder is involved. Even between 7.62mm rounds, there is a huge difference between the 7.62x39mm round used by AKs and the 7.62x51mm round used by NATO sniper rifles and the 0.300 Lapua Magnum.\n\nThe 7.62x39mm is the shortest round of the bunch and therefore the weakest, the 7.62x51mm has significantly more gunpowder behind it thanks to its much longer case, but the .300 Lapua Magnum has an even longer 69mm case that is 25% wider.\n\nYou really care about the volume of gunpowder vs the mass of the bullet, not even the diameter of the bullet."
]
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[],
[],
[],
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||
562852 | Are there any wild animals that are showing signs of adapting to cars? IE: Looking both ways before crossing the street | askscience | https://www.reddit.com/r/askscience/comments/562852/are_there_any_wild_animals_that_are_showing_signs/ | {
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"text": [
"Yes, in fact birds such as crows have been known to use cars to their advantage. They are able to learn when traffic stops and goes at lights and will then drop a hard nut into the road to be crushed by cars and wait for traffic to stop to retrieve the insides. So, not only some species adapting, some are using cars to their advantage.\n\nHowever, it should be noted that some species can't or will not be able to adapt to cars and that wildlife pathways are very important.",
"In Chicago, coyotes have adapted to traffic. \n\n_URL_0_\n\n\"The footage revealed coyotes astutely waiting on passing cars so they could safely cross streets, using sidewalks and other walkways, and even raising a litter of coyote pups in the top of a parking deck.\""
]
} | [] | [] | [
[],
[
"https://www.google.com/amp/www.chicagotribune.com/news/ct-downtown-coyotes-met-0117-20150116-story,amp.html?client=safari"
]
] |
||
2s8bjt | how does using cough medicine help your health? | I always thought cough medicine would be worse for you in the long run, since it stops you coughing up stuff that shouldn't be where it is. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2s8bjt/eli5how_does_using_cough_medicine_help_your_health/ | {
"a_id": [
"cnn38dp"
],
"score": [
4
],
"text": [
"It doesn't help your health, it simply suppresses your cough. IOW: It alleviates a symptom; it doesn't cure an infliction. "
]
} | [] | [] | [
[]
] |
|
5y7lh8 | what happens to dead bodies without any family or friends? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5y7lh8/eli5_what_happens_to_dead_bodies_without_any/ | {
"a_id": [
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"text": [
"Depends on the state but if there is no will or estate left behind then they will usually be cremated. In my area if organ donors are found this way they sometimes make it to our forensic labs to help with decomp analysis or experimental use for high profile cases ",
"Many counties have paupers cemeteries where they would bury unclaimed deceased. Now a days dye to cost, many bodies are cremated, and if their ID, etc is known the box of ashes will be stored for a bit trying to notify next if kin. "
]
} | [] | [] | [
[],
[]
] |
|
65prfd | how did nail polish become a thing? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/65prfd/eli5_how_did_nail_polish_become_a_thing/ | {
"a_id": [
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"text": [
"In Ancient Egypt and a few other ancient cultures the wealthy lacquered or otherwise painted their nails as a sign of status. The fact that they were able to afford the make-up and lived a leisurely enough life that they did not have to use their hands for labor thus breaking/damaging them was a major thing for the wealthy. That carried on through various cultures up until modernity where make-up became cheap and most people's jobs stopped being physical. ",
"So this is kind of bizzare- When women ovulate (so when they are fertile) they sometimes can have a slightly flushed skin tone. Some people realized it was attractive for a woman to add blush to her cheeks, and red coloring to her lips and nails. The subconscious reason it's attractive is because it's a sign of fertility. "
]
} | [] | [] | [
[],
[]
] |
||
2xt0oh | In WW2 did Germany control the food supply entering to and by how much the amount to Finland Sweden and Switzerland? | Did they leverage this to their advantage, i.e. forcing the Finns to attack/fight where otherwise they may not have. Are thee examples of Sweden and Switzerland being effected forcing them to consent to certain policies or exchanges or where they immune? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/2xt0oh/in_ww2_did_germany_control_the_food_supply/ | {
"a_id": [
"cp38lbe"
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"score": [
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"text": [
"Yes and no.\n\nSweden had a treaty with Britain and Germany ready at the outbreak of war to allow a certain number of ships through the British blockade and through the German minefields in the North Sea and Dogger's Banks. In theory, the Germans could strangle this trade after they had captured Norway in June 1940, but there were several other factors.\n\nGermany purchased about 10 million tons of Swedish iron ore. While they were not as dependent on it after they had captured the French and Belgian mines in Summer 1940, it was still a major boon to German steel production, as Swedish ore was high in iron content, pure and suited for making high-quality steel through the Bessemer process.\n\nSweden was also dependent on German coal and coke for its own steel production and power generation.\n\nThe whole trading business was thus a back and forth, where both sides needed each other. Sweden generally held a strong advantage though - Arne Beurling had broken the German landbound codes and the *Geheimschreiber* and the Swedes could often read the instructions the Germans sent to their legation and trade negotiatiors and knew beforehand what their highest and lowest acceptable levels were.\n\nSweden did have an effective rationing system and large strategic reserves of raw materials - from October 1944 until the end of the war, Sweden was cut off from trade as they stopped exporting iron ore to Germany (at Allied insistance) and was able to live on its reserves.\n\nSweden also fronted for grain shipments to Finland that Germany was to provide when the ice situation in the Baltic was unsuitable for shipment.\n\nBottom line - while the Germans had som leverage, so did the Swedes, and the whole thing was a see-saw back and forth as the war progressed."
]
} | [] | [] | [
[]
] |
|
2z52yz | why do humans seem to be the only animal that actively helps and feeds other strange* animals? | How many times do you see people helping a baby after it hurts itself. Or how many people feed wild animals.
How come you never see (I guess my question is DO they) a wild animal help another wild animal? Like, I've heard stories of wild lions and snakes taking care of a human baby. (Okay, not take care of but protect). What is going through these animals heads?
Do wild animals actively help other wild animals that are injured? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2z52yz/eli5_why_do_humans_seem_to_be_the_only_animal/ | {
"a_id": [
"cpfq9l4",
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"text": [
"There are cases, noy entirely sure why(instinct?) but there are cases.\nFor instance when X female mammal breastfeeds some other X mammal.",
"Many animals have a protective/parenting instinct. Dolphins are known to protect humans from sharks"
]
} | [] | [] | [
[],
[]
] |
|
1zosjs | if there was a nuclear strike, why wouldn't be able to make the missiles explode at a safer distance with a drone or a different missile? | I know that we can use missiles to shoot down other falling objects, so why couldn't we scramble a missile or drone to intercept and explode one before it reached its destination? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1zosjs/eli5if_there_was_a_nuclear_strike_why_wouldnt_be/ | {
"a_id": [
"cfvnbzt"
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"score": [
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"text": [
"ICBM's are extremely fast (upwards of Mach 23 on the LGM-30 Minuteman) towards the re-entry phase of the missile as it returns into earth's atmosphere. \n\nThe best odds would be to strike one before it re-enters earths atmosphere which would involve creating military bases to track enemy projectiles and send out missiles to intercept them - which means they have to be built close to the hostile country to be effective."
]
} | [] | [] | [
[]
] |
|
1duvoh | What is in the meat besides macronutrients and water? | For example 100g of grilled chicken breasts has 23g of protein, 1g of fat and 0,5g of carbohydrates and some water. Does my body in any way use that other 75,5g? What is it made of? | askscience | http://www.reddit.com/r/askscience/comments/1duvoh/what_is_in_the_meat_besides_macronutrients_and/ | {
"a_id": [
"c9u4ege"
],
"score": [
4
],
"text": [
"That extra 75.5g is water.\n\n_URL_0_"
]
} | [] | [] | [
[
"http://www.fsis.usda.gov/factsheets/Water_in_Meats/index.asp"
]
] |
|
1e48by | What is the earliest reference to inflation historically? | Did early civilisations understand that making more money devalued the money that already existed? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1e48by/what_is_the_earliest_reference_to_inflation/ | {
"a_id": [
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"score": [
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"text": [
"I don't know about the first reference in history, but the [Song Dynasty in China]( _URL_0_) is known for introducing paper fiat currency. By the 13th century they were issusing paper currency faster than it could be backed by metal coins and inflation was the result.",
"The pay increases of Roman legionaries imply inflation occurred in the imperial period. [Source](_URL_1_) for legionary pay over time. In addition the reforms to currency under Nero may have been a response to inflation (he reduced the weight of various coins, in theory devaluing them). Miriam Griffin discusses this I believe in *Nero the End of a Dynasty* as well as others elsewhere (will need to check as don't have a copy with me atm). Finally the Diocletian's Edict on Maximum Prices is an attempt by the Augustus to control inflation caused by various factors, including the minting of new currency by the succession of Emperors during the 3rdC 'crisis' - coins were an important 'PR' tool for new emperors. It set fixed maximums for the prices of a large variety of items from basic goods, wages for workers, industrial products to luxury items such as lions, silk etc. However, due to the creation of lots of new coins at the same time it almost immediately became outdated as inflation outstripped its limits. (Source unfortunately is undergrad lectures, though you can see the edict's text [here](_URL_0_)). \n\nNot sure if this is what you are looking for however, were you looking for an historical source identifying inflation as a concept?"
]
} | [] | [] | [
[
"http://www.chinaknowledge.de/History/Song/song-econ.html"
],
[
"http://www.forumancientcoins.com/numiswiki/view.asp?key=Edict%20of%20Diocletian%20Edict%20on%20Prices",
"http://www.jstor.org/discover/10.2307/301286?searchUri=%2Faction%2FdoBasicSearch%3FQuery%3Droman%2Bmilitary%2Bpay%26acc%3Don%26wc%3Don%26fc%3Doff&Search=yes&searchText=pay&searchText=roman&searchText=military&uid=3738032&uid=2&uid=4&sid=21102271161747"
]
] |
|
7zaami | Why did building with stone never really take off in America? | I'm no expert on Stone housing but it seems like there's a serious lack of stone-built houses in America. I know in Europe there are Stone houses pretty much everywhere and stucco houses...whatever stucco is. Why did Stone houses never take off in America? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/7zaami/why_did_building_with_stone_never_really_take_off/ | {
"a_id": [
"dun2gj3"
],
"score": [
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"text": [
"I’m not quite sure where you’re getting the impression that the United States or it’s neighbors do not have stone houses. The US has plenty of stone construction for both residential (see colonial-style homes as a major example) and public (the US Capitol, for instance) buildings. Many older houses feature a stone foundation or stone walls in the first floor. While there are plenty of houses made of other materials (brick comes to mind, as do wood and aluminum siding), that also isn’t to say that European houses don’t use those materials as well. \n\nIf you’re interested more in distribution, areas that are near quarries are generally more suited to stone construction, as building materials need to be transported over less distance and are this cheaper. There’s an interesting post on AskHistorians right now discussing the recycling of stone in European cities (which have, of course, been inhabited much longer than the major American cities) that might be of interest as well. "
]
} | [] | [] | [
[]
] |
|
96n2qp | why do so many game devs tie physics and other calculations to frame rate? | So many games ported to PC have horrendous support for higher refresh rates, which I know is because the developers have tied certain things like physics calculations to the frame rate. Is this done for a good reason today, or is this a relic of the bronze age of gaming that should and will get better? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/96n2qp/eli5_why_do_so_many_game_devs_tie_physics_and/ | {
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"text": [
"Because it's easier. There are two other options:\n\n1) make physics and logic still tied to the actual framerate but scale it by the time between each frame\n\n2) run physics seperately at a fixed rate and interpolate data when you render. So the FPS may be, say, 100, but physics calculations is still running 30 or 60 times a second.\n\n---\n\n1) has issues, notably that if you have very high framerates then you'll get into stability issues with 32 bit floating point numbers. It's also not deterministic (testing issues) and for games with replay systems, well, no luck here.\n\n2) is the most \"complete\" option, but it's also very complicated to implement.\n\nTo tie physics and kinematics into frame rate is a simple solution that does the job. For consoles where you'll only target one framerate, it's a practical solution. \n\nThese days, as third party engine use is more common it's not as much an issue, since the hard engineering work is already done by Unity or Epic.",
"Because it's quick and easy.\n\nWhen making a game you need to decide how often it's going to refresh. Since the player will only ever see the difference between two frames (if an update occurs between two updates corresponding to different frames, that specific refresh will never be seen by the player) it makes sense to link the refresh rate of the engine with the framerate - why waste resources on stuff the player won't even see? \n\nOf course, this does make sense on the specific condition that the framerate is constant. And a lot of players don't want to be tied to a specific framerate. ",
"It's the easiest way to get consistent physics on a platform where you expect a constant framerate. Game consoles are the most common example since they all have the exact same hardware.\n\nVariable frame rate means you either have to decouple the physics from the graphic frame update or write the physics engine to 'step forward' in time in variable-length time steps. Neither option are easy and it's very common to have strange bugs like falling through floors because of weird corner cases in collisions.",
"You're kind of misunderstanding the issue.\nDevs don't do it on purpose necessarily to mess with gamers, but it's something that can be remedied with properly planned programming.\n\nSo let me explain it as simply as I can without too much game dev garble.\n\nWhen programming anything, the speed of the program is automatically tied to the power of the hardware it's running on. Programmers can make their programs run on any platform at the same frame rate using an added calculation. (Time.DeltaTime in the Unity3D engine)\n\nGames for consoles only are usually programmed directly for the consoles specifications, and therefore programmers neglect to plan ahead with these added calculations.\n\nSo if a programmer doesn't plan ahead, a PC port can prove to be glitchy, because PC gamers usually run hardware much higher than current consoles.\n\nHope it clarifies a bit.\n\nEdit: This answer is 100% correct. Downvoting it won't make it any less right. Source? I'm a game developer, with a degree in game design. I've programmed and scripted for years. "
]
} | [] | [] | [
[],
[],
[],
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|
a2tu83 | what happens in the us when a president dies? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/a2tu83/eli5_what_happens_in_the_us_when_a_president_dies/ | {
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"text": [
"You haven't been paying attention. When Gerald Ford died they closed the stock market on January 2, 2007. When Reagan died the markets were closed on June 11, 2004. Not a new thing. It's a national day of mourning so the markets are closed and flags will be half mast. They have been doing this since William McKinley died in 1901. ",
"The same happened when Reagan died a few years ago. Federal services, banks, and the stock market shut down on the funeral day. The funeral is televised, including the processional parade. Flags are also flown at half staff from the announcement of the death until the day after the funeral. ",
"Well here the president declared a national day of mourning and practically that means that Federal Workers get the day off. Since some companies follow along with what the government does in terms of closures that does have a ripple effect and so Wednesday will be a de facto holiday. But a somber holiday, not a \"woohoo!\" holiday. \n\nThe \"stock market\" (there are a lot but principally the NYSE) doesn't have to close but apparently there is a tradition of doing so. ",
"ELI5 is not for current events. Questions like this are better in r/outoftheloop or r/askanamerican."
]
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[],
[],
[],
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||
2twtqb | why don't internet companies use the current electricity line infrastructure? you cant use the internet without electricity, so why not? | Surely it would be cheaper to use the current electricity poles and lines for new fiber connections than it would be to continuously dig up sidewalks and roads? Why can't companies just use the current above ground lines?
Even if the line goes down, the power goes out and computers won't work anyway? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2twtqb/eli5_why_dont_internet_companies_use_the_current/ | {
"a_id": [
"co30zcf"
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"score": [
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"text": [
"Not really cheaper. A couple outfits have tried it. The problem is that wiring for electricity isn't terrific for carrying high-speed data, and the filters/splitters/termination gear is expensive. \n\nIt does have some uses in low-speed data, but it's not a likely candidate to replace coax, fiber, or even twisted pair data cabling."
]
} | [] | [] | [
[]
] |
|
3askvw | why is it that, no matter which hotel i stay at, the hotel soap always seems to be the same in smell and dryness? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3askvw/eli5_why_is_it_that_no_matter_which_hotel_i_stay/ | {
"a_id": [
"csfkzrt"
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"score": [
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"text": [
"You probably stay at hotels in a similar price range, and over time they have polished their offerings to be rather similar -- in many cases even buying from the same suppliers -- because they know what the average customer wants.\n\nIf you stay at posh hotels, the soaps vary a lot and are quite nice."
]
} | [] | [] | [
[]
] |
||
4nloci | do 100% blind people see any particular color even though they are blind? if so, what do they see and why? | More so if they do see any color, how and why can/do they see that color. If they see nothing then how would you explain how that would "look" to a person who can see? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4nloci/eli5_do_100_blind_people_see_any_particular_color/ | {
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"text": [
"So many people incorrectly think that blind people see blackness in place of vision but that is still a sight based thing. They see the same thing you see behind your head right now. Nothingness.",
"IIRC, I remember reading about the blind and how they dream. If you are born blind, then that is it. There are no visuals or colors in your dream. If you lost your sight after having it, then there maybe color and images, but over time it lessens. I imagine this is the same for thinking of colors. If they've never seen it, they can't think it or visualize it. If it has been long enough after losing their sight, they may forget it.",
"I have read an interesting article about this. You might know there are some animals that have some sort of compass in their bodies. This way they can always sense what destination they are migrating at. Asking a blind-at-birth person what they see is like a migrating bird asking a human what they sense if they can't feel where the magnetic north is. \n\nTo put this in another way. Your field of vision stops at a certain point. If theres a mosquito buzzing around your ear you can not visibly see it. Is the mosquito in an area that is black to you? Someone who is born with only one working eye misses an entire area of vision. Is this part of vision black? No, his/her vision now consists of the part that he/she can see, like all of our visions are. \n\nBlind people don't see colour, blind people dont see black. Blind people simply can't experience \"vision or colour\" in the same way that you can't feel a magnetic force.",
"Can 100% Deaf hear anything? No. Why? Because they lack the parts that makes hearing possible.\n\nCan 100% Blind see anything? No. The same reason. There's no sensor that would tell the brain that there is something to see.\n\nIf you can see even 5%, the sensor is there but it's really weak.\n\nEdit: You can also think it this way: Where's your \"sixth sense\" that some animals have? Why can't you sense tsunami before it happens like some animals do? Because you lack that sense, and you don't know what it feels like to have it."
]
} | [] | [] | [
[],
[],
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