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ELI5 How it is determined where one ocean starts and another one ends? | 17 | It is largely arbitrary. The oceans are designated to aid navigation and geography. Of course there are general temperature differences and salinity differences, but it is just one big mass of water, which freely flows together. Of course the oceans don’t know they are separate, and whales swim between them heedless of what we call them.
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ELI5: How are roaches completely unaffected by mircowaves? | Alright, so we've got a *tiny* roach infestation right now, and they like to scurry around anyplace dark and cramped, like our microwave oven. Even when it's running.
I know that microwaves work by vibrating the particles of whatever's in them to create heat with friction, but why doesn't that work on roaches? I mean isn't fire super-effective against bug? | 31 | Someone mentioned this in a post not too long ago. Basically this guy was cooking food and noticed a cockroach running around in the microwave. Freaking disgusting but anyway.
The microwave doesn't heat food evenly. That's part of the reason for the rotating platter. The roach senses this and runs to areas of little to no radiation. | 22 |
[Warhammer 40K] What happen if you put Orky bits inside a human? | Let's say an insane and extremely good Chaos Apothecary, some insane Dark Eldar with fetish for surgeries or a deranged but good Painboy decided to place Orky bitz inside a Humie and maybe some tech to atleast stablize it. What would happen if the human somehow survive? Lets assume some good dose of WAAAAGH! Energy was added to the mix as well.
Will an Ork grow inside his body and come out like a chest buster? Would the fungi assimilate the human flesh and in turn make the Humie orky or would it create an insane Frankestein of Man and Ork? | 42 | The human would almost certainly die.
The Orkoid species is violent and dangerous at every level. Even single celled orkanisms are capable of putting up a fight, and so the human would likely be destroyed by microbial Orks, leaving its body to rot and feed the miniature Ork ecosystem now gestating in its corpse. | 49 |
[Star Wars] What judicial authority do Jedi’s have(if any)? Are they given authority by the senate? How do they interact with other authorities in the galaxy? | Inspired by another question I just read regarding Palpatines backup plan if he had just gotten arrested, so what exactly are the Jedi’s authority in the galaxy? They seem to stop and confront any wrong doing in front of them for the most part. All seem comfortable talking to other authority figures or appearing in the senate. Speaking of that why are they allowed in the Senate? Are they considered their own “government”? Any examples of Jedi’s overstepping their authority or being denied access somewhere? Seems like they kind of just allow themselves access everywhere and no one complains because of the force and their lightsabers. Do they have blanket judicial authority to just go on investigations and arrest criminals? What about chain of custody for evidence? What about proper investigation procedures for each planet/sector? How do the Jedi navigate what must be an impossibly complicated and even more confusing legal minefield as they run around being heroes? | 31 | The Thrawn Trilogy features Jedi arbitrating civil disputes that they just sort of stumbled upon, multiple times, with the implication that this is what they sort of normally did.
Most other resources suggest that the Jedi eschewed basically all political power and acted purely as police or peacekeepers | 27 |
ELI5: Why isn't Herbalife considered a pyramid scheme by the SEC? | 20 | Because they have skirted the edge of the legal definition of a pyramid scheme by claiming they are selling a product and not just recruiting more salesmen. But in reality once you are in, they drill home that you need to sponsor massively more and more people to sell the stuff. And once you have paid, you feel like a chump to just walk away and admit they suckered you. So you give it a try because...well maybe this will really work. But it doesn't. And by that time, you've grown bitter and just want to get away from it and it is too much trouble to try to get your money back and you tell yourself it was worth the money you spent to learn that lesson.
And while that may be true, they still have your cash. Multiply that across the globe and boom - Herbalife is rolling in the shit while you are left feeling like you were mugged. | 27 |
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[DC] Has Wayne Industries ever had some kind of program that rehabilitates and sponsors the education of ex-cons? Seems like a good way to give another option to all these random goons who get released from prison and go back to working for one of the crime lords in Gotham | 141 | Yeah, it's been mentioned now and again that Wayne Industries regularly hires ex-cons to help them get back on their feet. There's a fairly good BTAS episode that shows the Ventriloquist's reform in which going to work for Bruce Wayne is a major element. | 81 |
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[Dune] What would such huge creatures like sandworms actually eat? | So if I remember right the worm produced the spice... But how can the worms survive themself? Being insanely large the sandworms must have consumed tons of biomass not to starve... But in their habitat there was only... Sand, wasnt it? | 91 | The sand worms primarily eat sand plankton, which are actually the first stage in the sand worm life cycle, which is hypothetically trophically contained.
1) Sand plankton are microscopic organisms that feed on melange. Sand plankton mature into an adolescent form called a "sand trout" or "Little Maker".
2) Sand trout are free swimming "half animal, half plant" creatures that hoard water in cisterns underground bound by their own bodies. Given their half plant (even though they're mostly away from sunlight) nature, they are likely the autotrophic portion of the system and are said to contain a sweet syrup. Melange grows as a fungus within the underground cisterns feeding on trout excrement, and a spice blow happens when the build up causes the cistern to rupture (this kills the majority of the trout involved, but apparently not all).
3). Sand trout mature into sand worms, who presumably spore sand plankton. | 66 |
ELI5: Why is it hard to open a refrigerator door right after you close it? | 21 | You just closed a bunch of warm air in a box of cold things. The air cools really fast and the pressure drops forming a vacuum. It takes a few seconds/minutes for the few gaps in the door seal to allow enough air in to equalize the pressure. | 29 |
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ELI5: How video games are made | Specifically, large scale open world video games | 19 | Lots of people writing code, lots of artists making art, lots of designers thinking of what the game should be like, and lots of people to manage everything and make sure it all works, with tons of overlap. | 13 |
ELI5 The concept of making your bed, only to mess it up again. | 36 | You see, it's like this:
Say you don't make your bed in the morning. Then a fire breaks out, and the fire department responds. they go through every room of the house, and when they get to your room they see your bed isn't made, and then they go "hey look! brandana doesn't make his bed!"
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Does the fuse of a bundle of TNT set off all of the sticks at once, or does it trigger one stick which explodes, causing the others to explode? | 78 | Former EOD tech here.
Short version: The fuse itself does not initiate the TNT. The fuse (either electric or black powder) initiates a very sensitive primary explosive in a blasting cap. The explosion from the blasting cap creates a wave of heat and pressure that initiates the TNT which it is inserted into. This chain reaction (shock wave) expands outward from the point of initiation (the blasting cap) at approx. 6,940 m/s through the rest of the TNT.
It appears to happen all at once but actually happens like a wave, similar to dropping a pebble in a pond. | 52 |
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I’ve heard that the ratio in size between the human body and the smallest subatomic particle is equal to the ratio in size between the size of the known universe and the human body. Is this true? | I've heard this multiple times in my life, and I can't seem to find any concrete evidence of it's truth. Any help would be greatly appreciated. | 129 | An elementary subatomic particle does not have a size. Classically, they may be estimated to have a certain radius, or may be assumed to be point-like. But in reality, spatial descriptions of elementary subatomic particles are described by their wave-function, which is defined for all space. It can be interpreted that an electron, for instance, or some other elementary subatomic particle, is actually smeared throughout all of space.
Elementary subatomic particles are not baseballs. So the comparison is really nonsensical. But, lets talk about protons for a minute, something that isn't an elementary particle, is still considered subatomic, and is quite small. The diameter of the known universe is on the order of 10^26 m. The diameter of a proton is on the order of 10^-15 m. We are on the order of meters. So, really, if we consider the proton, we are much closer to the size of a proton than the size of the observable universe! As far as muons, electrons, quarks, neutrinos, etc... there is no comparison. They are different critters all together. | 167 |
At what point does the randomness of quantum mechanics become irrelevant? | I've heard that the Determinism theory was disproven because there is a complete randomness associated with quantum mechanics. However, some things, such as the motion of an object, can be predicted nearly exactly. At what point does the randomness become irrelevant and determinism takes over? | 17 | one useful rule of thumb is whenever the system is (much) larger than its characteristic wavelength. Since wavelength is inversely proportional to momentum, higher momentum objects often have very little quantum behaviour. | 13 |
If I am on, or near a ship, and it sinks, will I be sucked down with the ship, or will I remain on the surface? | If I am in the vicinity of a sinking ship, will the current and pull of the water pull me down?
For the sake of argument, would the result differ depending on the rate the ship was sinking, or if the ship was very big? | 79 | There is significant turbulent mixing created as a large object sinks. There will be areas above the ship where surface water is subducted. However, since the sea surface remains relatively flat, that subducted water is replaced by rising water; the net effect being zero. In any case, you don't want to be directly above a sinking ship. | 40 |
ELI5:What makes that 'pewww' sound, as fireworks get shot into the air? | 260 | As far as i know it is a pyrotechnic mixture called whistle mix. The two main components are potassium perchlorate and sodium salicylate or sodium benzoate. The powdered mix is pressed into a tube carefully (as it is sensitive to impact and friction) and when ignited acts like a rocket propellant which creates a high pitch whistling noise as the gases escape from the bottom. Titanium powder can be added for white sparks and iron oxide can be added to catalyse the reaction. The size and shape of the tube can change the sound of the whistle. | 95 |
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Ask Anything Wednesday - Engineering, Mathematics, Computer Science | Welcome to our weekly feature, Ask Anything Wednesday - this week we are focusing on **Engineering, Mathematics, Computer Science**
Do you have a question within these topics you weren't sure was worth submitting? Is something a bit too speculative for a typical /r/AskScience post? No question is too big or small for AAW. In this thread you can ask any science-related question! Things like: "What would happen if...", "How will the future...", "If all the rules for 'X' were different...", "Why does my...".
**Asking Questions:**
Please post your question as a top-level response to this, and our team of panellists will be here to answer and discuss your questions.
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Ask away!
| 101 | I have often heard the debate - is Mathematics invented or discovered? If you believed in the latter, it would imply that Mathematics is intrinsic to Nature.
If you subscribe to this opinion, how would you explain a concept like Complex Numbers existing in nature? Are Complex Numbers just a theoretical construct to represent a perpendicular axis? | 16 |
ELI5: Why, mainly in the past, only the women changed their surnames when married | What is the story behind this? | 25 | Traditionally, the woman leaves her family to join her husband who is now the head of her new family. It would follow that she takes the name of her new family.
Edit: this is why the father of the bride gives away the bride at the start of the ceremony. If the father is not available, typically, another male member like a brother or paternal grandfather will give away the bride. | 41 |
What happens to bees separated from their colonies? | A bee flew into my car when I was on the freeway home, and decided to just chill on one of the closed windows. When I got home, about 20 minutes away, I let him out and he flew away.
What happens now? Does he die without a colony? Will a new colony adopt him? | 42 | Depends on the bee. If it was a social bee, like a bumble bee or honey bee then she (almost all bees are female) will die.
On the other hand, some bees are solitary, so something like a mason bee might be able to find a suitable place to lay her eggs. | 13 |
ELI5: What prevents infections settling in cuts? | When I was a kid I often got a lot of cuts unattended. I never had any bad infections, but I do have a lot of scars from some of the bigger cuts. What prevented my body from getting a life threatening infection? | 29 | Your circulatory system is pressurized, so blood flows out of injuries instead of bacteria flowing *in*.
Then the blood hardens into a protective shield.
Some bacteria do get in, but you have a personal death squad of millions of cells who patrol the body for interlopers. Any cell that can't produce the correct paperwork when asked gets executed. The cell police don't play games.
Usually the combination of the outflow pressure and the police is enough to prevent any serious bacterial incursions, but they can happen if the germs are tough enough or the immune system is weak enough or unable to reach the infection site. | 126 |
ELI5: Why is it safer to turn off the engine/remove keys from the ignition when fueling a car? | 260 | Fuel emits a very flammable gas with a low ignition point. All you really need is a spark. On a windy day, when these fumes are dispersed quickly, it's generally ok. On a warm, humid, stagnant day, this can be very dangerous as your car is generating electrical energy while it runs which can easily spark enough to set off the gas. | 128 |
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ELI5: Why does the world feel quieter when it snows? | Just a Canadian waiting for the bus when it dawned on me how quiet it was. | 946 | It's harder for sound to travel through the air when there is snow in it. Same thing is true when it rains (but you might not notice it as the rain itself makes a lot of noise)
Also the snow already on the ground also works like sound dampening. As the sound can bounce much easier on the hard ground than the soft snow. | 831 |
[Marvel Comics] How different would Earth-616 be if a young Magneto had joined the Invaders? | In this scenario, assume that the classic Invaders (Captain America, Bucky, Human Torch, Toro, Namor) liberate Auschwitz in 1944 with the help of Erik Lensherr whose powers are developing. They convince him to join and aid their cause as Magneto, Master of Magnets.
1. In general, how does this shift history?
2. Magneto discovers that his teammate Namor is a fellow mutant. How does this change the way mutants are regarded by the rest of the world?
3. Alternate version: Magneto misses his chance to escape in 1944 during a revolt and instead is found by the Russians in 1945 when they finally liberate the camp. What changes for the USSR of they have Magneto on their side after the war? | 189 | 1. There's a chance Magneto doesn't become a villain if he's developed as a hero alongside Captain America, and he sees that there are people who will go out of their way to defend those who are different than them. Of course, Namor might convince Magneto of his superiority but probably not. Magneto would make sure the Invaders went to free the other Concentration Camps, and he'd be an extraordinary asset - particularly with Cap and his shield. He could have also saved Bucky from Zemo's rocket, preventing Cap from being super bummed when he was unfrozen and preventing the Winter Soldier from happening.
2. Magneto would publicize his and Namor's achievements in WW2 and they'd be regarded as heroes by the Allied propaganda machine. Potentially leading to a deeply religious country declaring that mutants were gifts from god to defeat the Nazi menace. Good early press lowers the amount of persecution they suffer later.
3. Magneto would probably treat Russia the same as he treats America in mainstream comics. He would of course have to read communist works if he were brought into the USSR government, and the Communist Manifesto talks a lot about alienation from your labor and exploitation of the worker. Magneto would see the USSR taking credit for his successes and then see that they're exploiting him for his mutant abilities. He would then become a mutant supremacist terrorist in Russia. | 98 |
[Arthurian legend] How would King Arthur feel if he returned to defend modern Britain as foretold, only to find that it is now overrun by the Anglo-Saxons he supposedly fought? | 125 | I actually think he'd be quite pleased. The assorted tribes of Britain are no longer soaking battlefields with blood to resolve their differences. Human rights and the celebration of human dignity have come a long way since before the Magna Carta, and that is what some of the British tradition celebrates the most (like with the whole concept of a round table).
I honestly think that the hardest thing for him (if you use the continental and Christian traditions, like Chretien as a starting point) would be the secularization of his kingdom. The quest for the Grail would be met with more of a "meh" today. | 60 |
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[Kill Bill] Why did Copperhead get to raise a family but not the Bride? | Was Bill just salty cause he had a thing for her or something? Just seems a lil unfair imo | 15 | There are 2 major reasons.
1) Vernita asked to leave, while Beatrix just ran away. Like all the other members of the Deadly Viper Assassination Squad, Vernita would have shared her plans to leave and start her family, and gotten Bill's blessing. On the other hand, when Beatrix found out she was pregnant, she just ghosted everyone, and that pissed Bill off.
2) Vernita wasn't in a relationship with Bill. Beatrix was and she just dropped him and disappeared, ran off and found some guy to marry in just a couple of months. And though she told him only moments before being shot in the head, Bill may have had a suspicion that she was carrying his child. Her running away wasn't just the end of their relationship, but in Bill's eyes, kidnapping his own child. | 30 |
CMV: Most of men's largest issues (suicide rate, homelessness, handling emotions, how they are treated around children, etc...) would be helped by feminism, as sexism is largely the reason for these issues. | All of the large issues that come up surrounding men (which I agree are a huge problem, these things also need to be handled) such as homelessness, suicide, not being able to talk about their feelings, feelings surrounding women and dating, children, etc... seem to all largely circle back to misogyny and sexism.
Men suffer with suicide and attempting suicide because they often feel they have nobody to reach out to because talking about your feelings is a "feminine" thing to do and men must be "masculine" because being feminine is seen as less than and weak by society, and men are not supposed to be weak. It's the same with homelessness, they get into a situation but feel they have nobody to reach out too. Often I hear men talk about how they can never share their feelings, but again, that is because we deem as a society that men need to be strong because women are... weak and therefore being feminine is also weak.
I say this because so often I see men saying that feminism isn't needed or that it is trying to push women above men, but it seems if you really look at it, implementing equality and egalitarian practices would mean that men would be given the opportunity to just be human and not have to feel so pressured. To me, it makes sense that feminism also helps men because when we put women in a box, it only makes sense that is going to force men into the opposite box and so we both end up stuck with the expectations of how we should be that can be suffocating.
edit: I find it interesting that most women disagreeing are simply saying that men need their own specific movements or groups to help with their issues separately to be more focused, while the men disagreeing largely seem to be saying that all feminism wants to do is drag men down and that women actually only care about themselves and are just pretending to care about men’s issues. It seems that the women and feminists in this thread have shown that is not true. | 55 | >All of the large issues that come up surrounding men... seem to all largely circle back to misogyny and sexism.
You are fundamentally correct, gender issues are two sides of the same coin. Patriarchal gender norms hurt all of us. In that way, yes, feminist goals and ideals do actually stand to generally help men in the long run.
However, feminism is not a direct solution to these problems. Feminism is focused on women's issues and women's rights in the here and now. Complex male issues like suicide, homelessness, mental health, body dysmorphia, sexual trauma, social support networks... are NOT any part of any feminist agenda and won't see any direct improvement unless we create movements and initiatives specifically targeting those things. | 40 |
ELI5: Why as you increase the speed of a song, the pitch gets higher. | 21 | Sound is basically vibration in the air. Our brain detects slow vibrations as lower notes and fast vibration as higher notes. For example on a guitar if you don't have you fingers on the string the entire string vibrates causing it to make slower vibrations. If you place your finger on the stringer and strum the guitar the sound becomes more high pitched because the vibrating part is smaller and thus vibrates faster cause it's smaller.
If you speed up sound like on a record, your effectively speed up the vibration in the song. Because your speeding up the vibrations you brain things the song is playing faster. | 11 |
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ELI5: Do different eye colours offer any specific benefits or disadvantages to each other (e.g. brown compared to green) | 27 | Darker irises work in the same way as the black stripes that baseball players put under their eyes. Because the irises absorb more light, it means people with darker eye colours are less sensitive to bright lights, but people with lighter eyes tend to have better night vision for the same reason | 55 |
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ELI5 why can't we produce blood and have to donate it from real people? | 4,174 | Just because it has one name doesn’t mean it’s one thing. Like a car is make up of lots of parts, Blood is also made up lots and lots of different pieces that are super tiny, so small, you can’t even see them, and they have to be fit together in exactly the right way for it to work. It’s still too hard for humans to put the pieces together in exactly the right way, but we’re working on it. | 3,436 |
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[God of War] I'm just a humble merchant trying to make an honest buck yet this angry Greek guy has gone out of his way to kill me three times. Who did I wrong, what great sin did I commit to deserve this treatment? Athena, answer me | 56 | Kratos is beloved by Athena. She will not answer you. He is intertwined with the gods since his birth. Some fear him, some are fascinated by him, some use him to further their entertainment and games with mortals. The gods of the Greeks do not exist to answer you, or serve you. You exist to serve them, and answer to them.
The fact that you demand an answer from Athena shows just why you deserve your fate. You don't understand that you exist to serve the whims of the gods. Even if your fate is to be horribly murdered that fate was already determined. Objecting to your fate. Not showing suitable obedience to the gods. These are things that gets a normal man struck down, cruelly.
The Greek Gods have literally destroyed entire cities because one person in the city didn't show them sufficient obedience. | 59 |
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ELI5: How do they get water up large skyscrapers | I've always wondered how they get water up massive skyscrapers like in new york or in india, please help!
Edit: Thanks for all the answers and videos! I appreciate having my question answered by a great community! and made my Front page! Thanks again!!! | 1,006 | with pumps! the pressure that is supplied by the water main available in most cities is usually only adequate to get water up around 6-8 stories. any building higher than that needs to supplement the water pressure in its system with pumps. | 547 |
ELI5: How are ovens able to cook at a lower temperature /faster by being fan assisted? | 234 | that is the difference between a conventional oven and a convection oven (one with a fan). the fan does two things. The first is it mixes the air in the oven, so you get a more even temperature throughout. This helps things cook more evenly. The biggest difference, though, comes from the flow of air through the oven. Moving fluids, be they gas or liquid, transfer heat faster that stagnant fluids. Stagnant air is often used as insulation. Conventional ovens do have some airflow due to the slight temperature differences between the top and bottom of the oven and having a heating element on the bottom, but this is minor compared to convection ovens.
TL;DR faster moving air transfers heat better than slow or non-moving air so a convection oven cooks faster than a conventional oven. | 207 |
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CMV: The two bombs dropped on Japan inadvertently prevented a nuclear war beyond that point in history. | All throughout the history of warfare we have witnessed and documented the evolution of weaponry, logistics, and the changing battle tactics that said weaponry and logistics force.
Generally speaking, massive consequences of previously unknown actions tend to change people's minds about trying something like that again. Whether it be accidentally burning your house down, eating too many hot dogs and having every orifice in your body punish you, or in warfare, Napoleon's invasion of Russia that didn't go so well.
**The point:** When America dropped two nuclear bombs on Japan, the world had never seen such devastation on that scale, where entire cities were destroyed in an instant. That's not something that is soon forgotten, and using them more becomes a frightening option.
This brings me to the cold war, and why we got to call it that instead of something worse. America and the USSR had many nukes, but neither ended up using them. I wager human desire to test out the big guns may have boiled over if it weren't for proof of how devastating and world-ending these things truly were. Sure, the testings in New Mexico and Nevada and wherever the USSR tested theirs may have given an idea to it, but that entire time you could point back to Japan and say "see? This is what will happen, only worse now."
Anyway that's my two cents.
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> *Hello, users of CMV! This is a footnote from your moderators. We'd just like to remind you of a couple of things. Firstly, please remember to* ***[read through our rules](http://www.reddit.com/r/changemyview/wiki/rules)***. *If you see a comment that has broken one, it is more effective to report it than downvote it. Speaking of which,* ***[downvotes don't change views](http://www.reddit.com/r/changemyview/wiki/guidelines#wiki_upvoting.2Fdownvoting)****! If you are thinking about submitting a CMV yourself, please have a look through our* ***[popular topics wiki](http://www.reddit.com/r/changemyview/wiki/populartopics)*** *first. Any questions or concerns? Feel free to* ***[message us](http://www.reddit.com/message/compose?to=/r/changemyview)***. *Happy CMVing!* | 25 | The firebombing campaigns caused far more destruction to life and property than the nuclear weapons did. The fact that they were devastating to one's enemies really wasn't that great an argument to restrict use.
Primarily, it was the development of intercontinental ballistic missiles (and submarine-fired missiles) that basically guaranteed that any use of nuclear weapons would lead to an immediate and unstoppable retaliatory response with nuclear weapons. This was called "Mutually Assured Destruction", and it basically took nuclear weapons off the table.
That said, both sides did come exceedingly close to using nuclear weapons again. Some of the US military leadership wanted to use nuclear weapons during the Korean War after China got involved, and the Cuban Missile Crisis took us about a blink away from an attack.
| 19 |
CMV: As a cyclist, I believe there should be no compulsion upon me to wear a helmet. | I regularly cycle, both for the total hell or it and also to get around, especially over shorter distances. In the 20 or so years I've been riding, I've never worn a helmet for anything other than those few occasions where it has been totally mandatory.
Now there's been repeated calls for cycle helmets to be made compulsory in the UK, and a petition drew 12000 signatures. Yet I've never seen any totally compelling reason why this should be the case. With the exception of expensive helmets costing fairly good sums of money, most helmets are little better than glorified takeaway cups made from polystyrene which are almost definitely not going to be of any use in real-life collisions, which typically average 30mph against the 10mph which the helmet tests use as a standard. I would rather see the money that would be used to implement such a ridiculous law used to build a proper network of cycle paths which would allow cyclists to ride in relative safety. That would be to me a far better use of the money.
So, CMV!
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> *Hello, users of CMV! This is a footnote from your moderators. We'd just like to remind you of a couple of things. Firstly, please remember to* ***[read through our rules](http://www.reddit.com/r/changemyview/wiki/rules)***. *If you see a comment that has broken one, it is more effective to report it than downvote it. Speaking of which,* ***[downvotes don't change views](http://www.reddit.com/r/changemyview/wiki/guidelines#wiki_upvoting.2Fdownvoting)****! If you are thinking about submitting a CMV yourself, please have a look through our* ***[popular topics wiki](http://www.reddit.com/r/changemyview/wiki/populartopics)*** *first. Any questions or concerns? Feel free to* ***[message us](http://www.reddit.com/message/compose?to=/r/changemyview)***. *Happy CMVing!* | 22 | Even while bicycling you can injure yourself seriously if you are not wearing a helmet.
But why should any of us care if you injure yourself?
Because it costs us money.
When you get a concussion and an ambulance comes and takes you to a hospital, it costs us money. Either through taxes, or through our insurance.
Either way, it's in our best interest for you to not get seriously injured when it was easily avoidable.
This is why there are helmet laws. | 18 |
ELI5: How exactly is a pulse ox able to detect the amount of oxygen in the blood? | 19 | It shines a specific color of light through your finger. That light has it's color changed by the blood in your finger and is then received by a sensor on the other side. The amount and type of change depends on the oxygen content of your blood. (Which is also why veins appear bluer than arteries.) From that it's a simple formula to give an accurate enough measure of blood oxygen. | 16 |
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Andromeda Collision | I've been told that the Milky Way is on a collision course with the Andromeda galaxy, but I've also heard that all the galaxy's are moving away from each other, how does this work? | 131 | Cosmological expansion only causes things that are already sufficiently far apart to expand away from one another. For things that are relatively close to one another, like the galaxies in the Local Group, the behavior is much more closely approximated by the standard picture of attractive gravity.
In other words, gravitationally bound systems (like galaxy groups) don't experience cosmological expansion. It's only when you consider widely separated galaxies that you find the distance between them increasing due to expansion. | 75 |
Will Build Back Better add to inflationary pressures? | I read that some believe the >$1trillion spending package won’t add to inflation. I was wondering how we can know that? What does add to inflation?
My thought is: if we take money from people/companies not using as much of it (via higher taxes) and spend it on infrastructure where much of it goes into raw materials and worker pay (who are more likely to use it), it seems like it should put more pressure on inflation? Especially in such huge volumes of money.
So, does it seem like it would be more or less likely to put additional pressure on inflation? | 38 | It's not a matter of BBB not adding inflationary pressure all together, it's more a matter of scale. In this case, if the current 1.5 Trillion dollar plan is passed, that would represent 150 billion/year in new spending, or a bit over 0.5% of the GDP on these social programs. They could have a broader effect than those simple numbers, but it's not likely that it will significantly add to inflation.
It's important to keep in mind that the bulk of the inflation we're seeing now is a result of supply chain constraints being tested and not the monetary/fiscal policies of governments, and we likely wouldn't be considering the potential for inflationary pressure for such a bill in most other contexts. | 45 |
Eli5: In this day and age how the hell can people escape from prison? | 43 | At the end of the day, a prison is a building with a security system limiting what goes in and out of it, and security systems are subject to flaws unforeseen by those who create them.
Consider how often we hear about security breaches in million dollar, professionally built computer systems. Hackers look for flaws in those systems to exploit and gain entry. In a similar vein, those who are able to escape from prisons have simply found a way to hack the prison's security system. Perhaps a door that must be manually locked is forgotten or missed by a lazy or tired guard. Or poor maintenance has led to a section of fence which can be pushed open.
When you have an imperfect security system being analyzed on a daily basis by a group of people who would like to break through it, sooner or later one of them will succeed. | 28 |
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ELI5: Why is SpaceX attempting to land a Rocket on a drone ship? | 43 | They're trying to develop a rocket that can land vertically and be used again. Due to laws regarding airspace and (mainly) safety regulations, they can't try this over land, so they built a barge out in the water where they can legally develop the technology. | 29 |
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ELI5: Why do some programs crash/become unresponsive when minimized? | Skyrim is a huge example for many people. Why can't some programs do this? | 28 | Let's say your computer is a line of students (programs) in primary school waiting to be served lunch (processing resources).
Skyrim, the school bully, has the notorious reputation of beating other kids up to get the Fullscreen pass which allows him to cut in front of the lunch line so he gets the highest priority for the food.
A new teacher, Mrs. Minimize, notices the bullying and forces Skyrim to the back of the line. Since Skyrim is always used to getting the highest priority for food, he gets extremely upset. If he isn't first in line, then no one should be! He charges through the cafeteria, crashes the table of food to the ground, and stomps his way out.
Summary: Some programs are used to getting high priority for processing power. When minimized, they switch to low priority which could cause processing issues, causing them to crash or become unresponsive. | 26 |
Eli5: Is there any explanation why when we sleep it seems like time is so fast? For example, ive been asleep for 9 hours but it feels like just a minute. | 16,753 | Time passes inconsistently based on how aware of it you are. Five minutes doing something unpleasant feels a lot longer than five minutes doing something you love, because you are keenly aware of the time passing when you're waiting for it to reach a certain point.
When you're asleep you aren't counting the time, and therefore it doesn't have the slow down effect. | 8,885 |
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[Incredibles] What happened to all the villains that were around? | Assuming the Supers world worked like our own comics then every Super has at least 3 villains that they fight. When the Supers go the villains presumably wouldnt. Did the government just go the way of the Syndrome with them? | 39 | We never see any super powered villains. They're all mundanes with gadgets.
Without superheroes to oppose them, they don't need super gadgets. They just returned to using guns and crowbars like the good old days. | 37 |
What if in the future space mining become true, think about Federal Reserve Bank of New York, all funds that are stored in gold and other metals are now priceless (if prices of gold and other metals drops). How would that affect the global economy? | 27 | Some data.
* The US Government has a gold reserve of about 11 billion USD.
* The US GDP is about 19 trillion USD per year, or 52 billion USD per day.
* The US federal government revenue is about 3.6 trillion USD per year, or 9.9 billion USD per day.
So the US government has a gold reserve that is about:
* 5 hours worth of GDP.
* 21 hours worth of federal revenue.
Even if all the gold vanished overnight, it would be little more than a footnote in the US government budget. If we had a technology that made it inexpensive to mine gold and bring it back to Earth*, whatever that imaginary technology might be would have an effect on the global economy many orders of magnitude greater than the value of the now worthless and abundant gold.
_________
\* Which, spoiler alert, we probably never will, because of the laws of thermodynamics. | 25 |
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CMV: Celebrities do have it easier. | I always hear celebrities saying stuff about how fame wasn't what they expected and how it's gotten to them and if they could do it all over again they wouldn't have chosen the fame. I get that maybe the attention might be too much but at the end of the day you're rich and famous and can get what you want, etc. I think the main thing is that it seems like they forget everyone struggles. Like they think all of their issues will disappear and they'll have a perfect life without the fame. Everyone else has a lot bigger problems than they do, especially in terms of money. | 101 | I’d say that’s absolutely true...until you have struggles. Imagine if you will, the experience of drug addiction as a celebrity vs. some no name joe q citizen. The entire world gets to experience (and comment) on your downfall...that’s something none of us could possibly fathom. It’s certainly a much higher mountain, but god help you if you fall off it. | 59 |
CMV: Portraying fit/attractive actors as characters that eat junk food all the time and never work out is irresponsible and damaging. | I really started to take diet and exercise seriously and found that to reach certain target body types, it's massively more challenging than I expected. I partly put this down to TV constantly portraying these young, attractive, fit, successful people as eating junk food all the time and never working out. I don't consider myself a particularly naive or impressionable person so I don't consciously form my views on this from TV but over time it happens subconsciously.
It happens with most characters in TV, sitcoms especially but lets take Joey from Friends as an example. He's eating pizza constantly, he eats an entire turkey, the meal for 6 for 1 etc. He's seen to be working out once I think, immediately hurts himself and says 'why did I have to start lifting weights again?' - indicating this isn't something he normally does. Despite this he's a good looking guy and in good shape.
By contrast I'm a similar age and height/build and only after a solid year of working hard in the gym 3 times a week and eating right am I starting to look like that. (Starting point was just 20-30lb overweight). By the standards set on TV and adverts for 6 week abs etc., even after considering that those standards aren't reasonable and adjusting my targets accordingly, I was still disappointed with such a minor change. I think TV in general wildly misrepresents what lifestyle you need to lead to achieve a certain body type.
I understand why they do it for TV. If someone is attractive, they are immediately more likeable. If they also like junk food and lying around on the couch, they are more relatable - making them more likeable again. I'd just like to see more shows address this, I think it's harmful for people's body image and very demotivating when they see what they perceive to be slow progress.
Maybe I'm in the minority though, I've never heard anyone express this view before, I'm open to changing my mind. What do you guys think?
EDIT: Thought of another good example after posting. Look at Jake and Terry from Brooklyn Nine Nine. Jake looks in pretty good shape but is portrayed as a guy that eats junk and never works out, in reality I'm guessing Andy Samberg is pretty careful about what he eats and probably goes for a run regularly. Terry is portrayed as a guy that just eats right and exercises whilst working a job and having a wife and kids. In reality his body type is only possible if he uses steroids and spends probably 3-4 hours a day working out - virtually impossible alongside a full time job, wife and kids.
EDIT2: Maybe I didn't make myself clear because a lot of people seem to have misunderstood. I'm not asking for TV shows to show these people working out or eating healthily. I just don't want them to actively portray that they regularly to do the opposite like the Jake and Joey examples. | 100 | This isn't a problem with tv, it's a problem with human biases.
Consider two friends that you eat lunch with every day at work/school (you know back when that would happen...). One is fit, and eats whatever looks good from the cafeteria. The other is trying to get fit, and eats a small, undressed salad every day. From your perspective, it would seem that the salad eater should at least be trending to being more fit, while the other trending to being less fit. But you don't have sufficient information to make that assumption. We actually have no clue whether each friend consumes more calories per day than they burn, we only know how many calories they chose to consume at lunchtime.
TV is like just seeing someone during lunch. No tv show gives you 24 hour-a-day access to a character's behavior. Not even 24. Taking the behavior you see in the tv show and assuming that extends to how that character acts 24/7 is to make the same fallacy as assuming your trying-to-be-fit friend has a healthier lifestyle than your fit friend. | 19 |
[Star Wars] What would have happened if Obi-Wan Kenobi had escaped the Death Star alive? | Let's assume group escapes without needing Obi-Wan to distract Vader. Obi-Wan goes to Yavin IV with Luke on the Millenium Falcon as the Death Star approaches.
How do the events of the series unfold from there? | 23 | Obi-Wan and Luke both pilot X-Wings during the Death Star assault. Vader barely makes it out in time to survive the explosion, but is in no shape to dogfight Luke or Obi-Wan. Wedge survives.
Luke still heads out on Hoth, but being more adept in the force, the wampa attack is detected sufficiently in advance that it becomes a simple dismembering from tauntaun-back. Luke reports in that there are space-bigfoots about. When Han reports that an imperial probe blew up, Obi-Wan immediately declares that they must abandon Hoth. As a result, Vader's fleet arrives to find an empty and abandoned Hoth.
Obi-Wan and Luke both go to Dagobah, and Luke's training isn't interrupted to save his friends since... they don't need saving. Luke manages to become a full Jedi and divines on his own that Vader is his father. Yoda and Obi-Wan teach Luke how to handle force-lightning.
Return of the Jedi plays out pretty much the same, except that Luke easily bests Vader in combat without succumbing to anger, and isn't immediately roflstomped by Palpatine. Sensing a real chance at victory, Vader turns on his master (this was his plan as indicated in Episode II) and the two of them dismember the emperor without much incident.
Vader fails to take command of the Empire, and is unwilling to join the rebellion. Yoda still dies from space-flu. The empire, without a strong leader, begins to unravel itself and an emergency senate is created in a final hope to restore order. | 27 |
[LoTR] it’s my understanding that the Istari were forced to limit their involvement and use of their abilities in Middle Earth. If Gandalf were allowed to go ham on the forces of Sauron, how much damage could he have done? | Could he one-shot any of the Nine? How powerful would an unrestricted Gandalf be compared to Sauron before the end of the Third Age? | 193 | We saw Gandalf the Grey go all out against Durin's Bane. Because he is confined to a living body (even if it is much more than a simple old man's frame), he is still quite limited in terms of raw magical power. The last time forces beyond Middle Earth intervened against evil, continents were shattered, species were wiped away, and the entire world was quite literally reshaped. (from a flat plane into a sphere)
Gandalf the White had a little more leeway given how desperate the situation became. But even then, the majority of his influence still came from his ability to inspire and lead, rather than cast divine fireballs at the enemy. With a slightly more powerful figurehead to rally behind, the armies of men had more hope, and thus fought a little harder than they might have if Gandalf had somehow remained in his original incarnation.
Even when Saruman abandoned the mission, he was still in his living body, and his magic was mostly in his voice. And he died to a dagger in the back, so he wasn't some sort of all-powerful being wading amongst the mortals. | 190 |
[Psych] - Was Shawn naturally talented or was his ability through training from his father? If a combination of both, did his father train him because he knew about the gift or would he have raised him that... rigorously if not? | 19 | Henry had trained himself to an extremely high level of skill, so he knew that it could be done for anyone (Henry being a dedicated cop, but knowing he was nothing special). So he trained Shawn, hoping that he would be a cop, and knowing that he could be taught, irregardless of Shawn's initial skill level. | 19 |
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ELI5: Why is it important to serve different types of alcoholic drinks in different styles of glasses? Does it affect the flavor somehow? | 20 | It can - some large volume glasses like a wine glass or brandy snifter are designed to create a large bouquet that you inhale when you stick your nose in the glass.
For most though, it comes down to presentation and volume.
A single whiskey on the rocks would look like nothing at all in a large highball glass. Conversely, drinks with ice and lots of mixer require a larger glass.
A stemmed glass (or a martini glass) is designed so you can hold the stem, yet not warm up the chilled drink contents, yet has enough open mouth so you can smell the bouquet. Or hold 11 olives if thats your thing. | 20 |
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We say the universe is roughly 13,75 * 10^9 years old. Given that time is relative, from what perspective is this measured? | Edit: After reading a bit about cosmic time I think Coin-coin answered my question in the point I was looking for. Thank all you guys for your contribution, didn't expect that much feedback. | 1,077 | It's what we call **cosmic time**.
In our model, the Universe is homogenous and isotropic. So there is a special frame: the one in which the Universe is isotropic. If you move in one direction in this frame, you will notice that the Universe doesn't look the same in your direction of movement as in the other directions.
The reference time is the time measured in this special frame. | 547 |
[MCU] Did anyone get snapped peacefully in their sleep and then get brought back in their same bed unaware of what happened? | As the title says like would they have tried to get their work day started Shaun of the dead style totally unaware of the chaos around them? | 773 | Statistically, absolutely. Though it's unlikely they could remain blissfully ignorant for long, given things have significantly changed in those five years. If you're lucky, you find your home still owned by your family, who are shocked to see you. If you're not, it might be owned by total strangers who take you as a home invader, or it might be abandoned or demolished. In any event, you're very confused and in an unexpected chaotic situation. | 667 |
ELI5: Why is the No Child Left Behind Act considered a failure. | Throughout my entire life I have heard people put down the No Child Left Behind Act but from what I could tell by a simple google search the act was intended to provide educational opportunities to many kids who would not have previously had them as well as raising national education standards. Was there something in it that was fundamentally flawed or did it simply just fall short of this goal? | 138 | Schools could only get more money through testing, which resulted in multiple grading scandals. It also forced kids through the system who were maybe not ready to advance as quickly as they did. This would set back students who were testing at grade levels. It essentially dumbed down everything, forcing all students to learn at the lowest-performing levels. Besides the funding issue, it seems like an ideal thing, to not let kids down no matter what, but it ends up holding others back. | 106 |
ELI5: Why was a steroid use in professional sports a congressional matter? | 126 | I can't speak for other professional sports, but baseball tends to get more attention from congress because it is the only business that is exempt from antitrust laws. Since it is a legal monopoly, there can never be a competing professional baseball league. With that kind of market power, it was thought best to regulate it in a public arena. Since steroids could be considered corruption of the integrity of the game and since the free market is not at work... Congress gets involved. | 93 |
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[Marvel] Does Captain America need to exercise? | In both the Avengers and The Winter Soldier they show Cap exercising, first by hitting a heavy bag and then by jogging. With the super soldier serum does Captain America actually have to exercise? Is it just recrational for him? A habit he picked up when he was scrawny and never stopped? Or does exercise actually increase his physique beyond what the serum did for him? | 140 | He excercises to maintain. The serum gave him very rapid muscle growth and in general boosted his physical upper limit. However to stay there he has to excercise like every other person. If he stops his muscles will start atrophying like they do for bodybuilders who quit.
Besides it gives him something to do with all that pent up energy. | 164 |
Becoming part of academia in a foreign country? | Hello everyone, in the future I hope to obtain a PhD in Psychology (specifically Clinical Psychology) from here in the U.S.
My question is what are the opportunities of being apart of research/academia at a university in a foreign country? | 28 | It depends. Some countries are more closed than other. And within those countries, some universities and departments are more closed than others.
If it comes to a you being 100% qualified for a job and McLocalface being 80% qualified, in many cases they might still hire McLocalface. | 45 |
ELI5: How/why did dogs evolve to be so loving and loyal to man? | sometimes I think my dog loves me more than I could ever love anyone or anything and it seems like a miracle pls explain | 66 | Loyalty is a benefit for wolves in a wolf pack, it lets them cooperate and work together.
Humans bred that aspect of loyalty to a high degree in dogs, effectively making some aspects of dogs "eternal wolf puppies", always loyal to the pack leader, ready to do as told.
Only wolf puppies bark. Wolves do not. Dogs bark at all ages. | 56 |
Intimidating Advisor | Doc student in a STEM field here.
I saw numerous posts on similar situations like this – but I am wanting to hear some direct thoughts on my situation.
My advisor is a well-respected scholar in the field. We haven’t had any “conflict” yet, but I am having doubts about whether I should continue to work with her. I don’t know why, and maybe this is on me – but I get so anxious around her. It’s to the point where I have to take my “as needed” anxiety medication whenever I speak with her. Her presence is intimidating, even when we are just talking about our daily lives.
She is a highly ranked professor in my department, which also means that she has a lot of $ and power. She can fund me on different projects that other faculties may not. One thing to note though is because of the political environment in my department, there are faculty members who are on the opposing side of my advisor. I didn’t know politics in academia can be this bad until I entered one. I thought about switching numerous times, just because her presence is so intimidating to me for some reason. The way she talks can be “short” sometimes, and whenever I share my interaction with her with other students, they often think I am not being treated properly. I personally haven’t felt like I was being mistreated until others started pointing it out to me. I don’t know if I’m seeing her with rose-colored glasses because of all the opportunity that comes by working with her. The only other faculty I will be interested in working with is my advisor’s worst enemy. How do I know? She made it clear to me on day 1, that if I were to ever work with the other faculty, I will not be working with her anymore. I am afraid to change advisors as I don’t want to lose the opportunities. But it’s taking such a huge psychological toll on me. How would you all go about this situation? | 55 | It’s hard to really know what is happening here but many busy people are “short” when they speak. They didn’t become a top professor by spending the day chitchatting. That in itself doesn’t seem a problem but it’s impossible for us to know the real picture. | 57 |
[MCU] Had Thanos tried to collect the Stones peacefully, would anyone have even noticed or cared? | Let's say he collected the stones through trades, money, favors, etc. Without using any violence at all.
Without telling anyone he had already collected the previous ones.
Could he have done this and completed his mission successfully without anyone caring or even noticing? | 40 | He only knew the Space stone was on Earth because Loki told him, the Reality stone was revealed after Dark World and was in the hand of the collector, who wouldn't trade it for anything because there's literally nothing rarer. Time stone was in the Sorcerer Supreme's hand and she's not insane to give it up. The Power stone he tried getting in secret, but Ronan betrayed him. The Soul stone's location was only known by Gamora, and nothing but violence would get her to talk.
Even without those factors, he was infamous for his half-genocides that he can't move around without the galaxy looking at him. He only decided to attack when he knew where most of them were and could reach them before anybody could react. | 71 |
Any literature/guidance on writing a purely theoretical master's thesis? | I'm currently a master student of sociology and decided with my mentor to write a purely theoretical thesis. However, I couldn't find any good guidance besides Umberto Eko's "How to Write a Thesis", everything I found was research-based (theoretical framework, method, results, discussion).
Any help would be welcome, even your own advice. | 65 | Rather than books - which may be entirely unapplicable to your specific situation - ask your advisor for examples from their past students, and find relevant examples for yourself.
Pretty much every university out there puts masters theses online, usually through the university library. Go find some examples of the kind of thesis you're doing, in similar fields, for the same type of degree, and from whatever country you're in (since the standards/expectation for masters thesis vary a *lot* by country and type of degree). Skim through several. Look at how they're structured, how the work is introduced, how much depth there is, how the different sections are related to one another, etc etc, and go from there. | 34 |
ELI5: How is it possible to have a working cellphone in minecraft that can call the real world? | [video](https://www.youtube.com/watch?v=IdlZRhKmWJY) for verizon's project that did this | 244 | Well, why wouldn't it? It doesn't actually "create actual signals in a virtual world that somehow seep through into reality". You don't really need those towers and phones and particle effects, that's just for show.
Minecraft runs on a computer, and a computer can access the internet, make calls with skype, and a lot of other things. Using these functionalities through Minecraft is pretty cute, actually.
It's really just a fun and playful way of accessing computer functionalities that already exist. | 229 |
ELI5: Why is it that when walking home I moderately have to pee, but upon reaching the door and stepping inside it feels like I'm about to piss myself? | 66 | This will be an example of trained reflexes in your body. If you are out and about there is not going to be a toilet anywhere, so you're not in the situation you'd usually be in if you were to pee. Your brain registers this on a subconscious level and tells your body "don't piss right now". Obviously you have to piss eventually, so your bladder will let your brain know that it's pissing time and you'll feel a little need to pee.
When you get closer to a piss destination your body will be all like "hey yo it's pissing time let's do it" and start prepping your peehole for pee pee, thus the need to piss gets bigger. It's just you associating home with being able to piss that makes it seem more urgent. | 47 |
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CMV: we’re all a bit racist | And that’s ok. Nobody’s perfect. Being racist can be as little as being judgy. Have you ever been judgy? Sure you have. We all have and that’s ok. It’d be seen as a bit scummy but ok. But once you judge a race, that’s seen as racism. Try it, I don’t think you could find a topic you could judge on without seeming racist. I also don’t believe that’s true racism but it’s just seen as that. I feel like I’m going to be judged for this but if I was a race that’d be racist.
What I’m trying to say is that we’re all racist cause we all judge and if we judge another race at all that’s seen as racism. | 22 | Hypothetically, if there was a person who lived their whole live on an island where everyone was the same race, and had no exposure to other races existence, and didn't even know the concept of race, could that person possibly not be racist? | 26 |
ELI5: Why am I so tired throughout the day and can easily fall asleep, but the second I'm in bed, I'm wide awake and take hours to fall asleep? | 40 | During the day, demands for your time and attention are omnipresent, sleep is a desirable way to escape them.
Once you're in bed, all the distractions have been silenced and now you have time to think about demands, worries, concerns, etc. | 18 |
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Is (-1)^∞=0? (I am 13 year old so please explain it to be understood for my age) | Hello! A few months ago I wondered what is minus one to the power of infinity. I didn't know that something such as calculus existed. But I said it must be zero because it can't be positive because there is always a -1 that will make it negative, and it cant be negative because there will be always a minus one to make it positive. Zero is the only real number that isn't positive nor negative so it must be zero. But now when I know a teeny weeny small bit of calculus I have better proof. I saw a short YouTube video that said 1-1+1-1+1 forever makes 0.5(i did my best to make an equation for that, it is on the image down below). And it makes sense. The value after each operation changes between 1 and 0, so we picked the number between 1 and 0 which is 0.5. And what's the difference, if we keep multiplying -1 we get -1 and 1 and the number between them is 0. I explained this to my teacher but she didn't think it was true but also she wouldn't bet 100$ for that(I don't know any idiom for an uncertain person in English, sorry). A calculator said it can't evaluate it. Is it undefined? Minus one to the power of infinity can be written by an equation on that image, so what's the difference between multiplying things infinitely and adding them infinitely? Or I am true? Feel free to correct me where I was wrong. Btw sorry for my bad English and wobbly handwritig.
https://preview.redd.it/fs3pizsrwu291.jpg?width=3413&format=pjpg&auto=webp&s=3836861bbd56538903221657c837978b75b4433c | 56 | That's a good question!
As u/drafterman said, ∞ isn't really a number. It's more of a concept to show a value that's so big, that it can't really be counted.
So, what does this mean?
If we want to use ∞ somewhere, we are really looking at a number that's really, really, really big. However, there's no "final" number we can reach -- there's always going to be another bigger number that we can find. So, what we want to do, is try using bigger and bigger numbers, to see what value the expression approaches (gets close to).
Let's say, instead of -1, you used 1/2 as your base. Now, what would (1/2)^(∞) mean? Well, ∞ is really just getting a number as large as possible. So, let's start trying to put really really big numbers where ∞ was. As you keep on putting bigger and bigger numbers, you will notice that the value of (1/2)^(some big number) gets closer and closer to 0. So, we might say that (1/2)^(∞) = 0.
Now, let's try this with -1. Now, what would (-1)^(∞) mean? Well, similar to what we did before, we're going to try putting bigger and bigger numbers in the place where ∞ was. If you keep on trying this, you'll see that you keep on getting either -1 or 1. You might even notice the pattern that (-1)^(odd number) = -1 and that (-1)^(even number) = 1. Now... the problem here is that our values aren't really getting closer two one number in particular. The values keep on jumping/bouncing between -1 and 1. If you wanna be fancy like a mathematician, you could say that the values "oscillate" from -1 to 1. Since we're not getting closer and closer to one number in particular, but rather, we are oscillating (jumping) between two numbers, it doesn't really make sense to define (-1)^(∞) as one specific number.
Now, what if you thought: "since we are consistently jumping between -1 and 1, why don't we define (-1)^(∞) as the average! That would be (-1 + 1)/2, which equals 0. You could do that, but it doesn't really make sense that much, because our values of (-1)^(bigger numbers) don't actually get closer to 0 - they jump around 0, and do not actually approach/get close to it.
This is more or less the definition of a limit at infinity, if you're looking to learn more about it.
It's a similar case with the sum 1 - 1 + 1 - 1 + 1 ...
It keeps on oscilating between 1 and 0. You could say that the average is 0.5, but the values doen't actually get closer to 0.5 whatsoever.
It's kinda weird to think that some things don't have a definitive answer and are just "undefined", but it tends to be the case with lots of things in math. | 98 |
ELI5: why do we expect organizations like the NFL to punish players for illegal things they do off the field? | Shouldn't that solely be handled by the legal system? Yet all you hear is bitching when a player does something illegal in their personal lives and only gets a slap on the wrist from the NFL. | 17 | The NFL is a media juggernaut, so one would think they have a certain moral responsibility. But really, like most things, it's about money.
The NFL has sponsors, and those sponsors don't want their product associated with wife-beaters, child-abusers, and murderers. Same reason Donald Sterling was forced to sell his NBA team. On the surface, the other owners said they were "appalled" (for PR reasons). But really, he was hurting their bottom line. | 14 |
ELI5: How can water vaporise at every temperature if it requires heat from outside? | What about below 0 Celcius, or when you put some water that's colder than the room's temperature( before the temperature of water and room equals)? | 17 | What happens when water (or any other liquid) evaporates, is that a molecule of the liquid at the surface has enough individual energy in order to overcome the attraction of local inter molecular forces. The temperature of the water is essentially the average energy over all the molecules; it does not represent the actual energy of every single molecule. As such, some molecules will have less energy and some will have more. As they move around and bump into each other, energy is exchanged and constantly in flux.
Because of this, at any point some molecule of water at the surface might have enough energy to escape and become vapor. The lower the temperature, the slower this process, of course. | 13 |
Eli5: How did the first weight get weight to know how much it weights? | 19 | It more-or-less went, "We need to define a weight, so we take this object and say that it defines the unit and calibrate our scales to match." In the case of the kilogram, it was defined as "the mass of one liter of water," and so no matter how massive one kilogram of water actually was, that mass set the definition. | 50 |
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[DC/Marvel] Who are the biggest Heroes operating outside of the US? | England, France, Germany, Canada, Australlia, Mongolia - there must be heroes from all over the place doing stuff all over the place right? Who are the biggest guys from these countries? | 24 | Batman Inc has members in many nations- Nightrunner in France, Black Bat in Hong Kong, etc. The Great Ten are the most prominent heroes of China. England has Knight and Squire.
In Earth 616, China has the People's Defense Force. In Britain there's Excalibur, MI-13, and Captain Britain. France has Les Heroes de Paris, a team Ben Grimm joined for a short while during the Civil War. | 27 |
ELIF- How does a hot air balloon work? How does the pilot know where they're going to end up and what happens if it all goes wrong? | 321 | Controlling a hot air ballon is a lot of guesswork. Educated guesswork, but guesswork nonetheless.
By controlling the heat inside the actual ballon (this is done using gas burners) it's possible to control if the ballon is rising (because it's hotter than the surrounding air) or declining (because it's colder, respectively.).
The ballon also has a valve at the top where you can let hot air out, to speed up the process of cooling down.
And that is really all there is to it. Hot ballon goes up. Cold ballon goes down.
Actual navigation, though, takes skill. A ballon is always and indefinitely moving in the direction the wind is blowing. Which means that if you want to go west, you'll have to wait until you have wind blowing towards the west.
Complicating things a bit, wind can blow in different directions at different heights. Which means that you can go higher and find a patch of wind going in sort of the right direction instead of staying low and going in the exact opposite direction.
The easiest way to find out exactly how the wind is blowing above you is to release a small helium ballon (because helium ballons always go up) and see in which direction it goes when the wind grabs hold of it.
The rest is all about skill. Knowledge. A tour ballon pilot would typically have several pre-planned routes to choose from depending on wind direction. "If the wind is blowing westward, we'll have to start east of the national park with all the wild animals. And land someplace west of it." The problem is the "someplace" bit, because you don't necessarily end up where you intended to.
Most aircraft can fend for themselves and force a direction they want with a propeller, but an air ballon just...can't. So, to simplify things for everyone, air ballons got their own set of aviation rules where other aircraft has to make way for them. The obvious issue here is of course that ballons are not necessarily welcome in any airspace, because the extra considerations everyone else has to make for them.
Things that typically go wrong is that the wind changes at the exact worst thinkable time, pushing the ballon towards a high voltage power line. Or, you know, towards a forest. Or a cliffside. Any place where you can't immediately land is a risk that the pilot would try to avoid. Passing a risk area means that they have to plan ahead.
When all you can control is height, you'll have to go higher. Because if you can only go up, then you are soon out of options. But if you can also go down, then you got two options to choose from.
What happens when the ballon risks running into a power line is that the pilot has to consider the two options. 1) burn gas and get more heat so that the ballon slowly rises? 2) release hot air so that the ballon quickly goes down?
Going down is always easy. Going down comfortably, thats more difficult. Going down comfortably when you are in a hurry, When you desperately have to come down immediately, that takes skill. And could definitely involve bruises as a calculated better outcome. | 259 |
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ELI5: What is going on in Nevada's DNC race, and how does it affect the final result? | Everything I'm reading is a clusterfuck of information that is tricky to decipher. | 39 | It's a caucus, there's 3 stages. Hillary won the first stage. Not enough of her people showed up for round 2 so sanders people filled in the missing spots gaining him the victory so far. Round 3 yet to come | 15 |
ELI5: Where does "The Floor is Lava!" come from, and how did everyone invent it as a kid? | Idk about you guys, but I definitely played the game "The Floor is Lava" as a wee kid. Not only that, but being that young, I'm pretty sure I invented the game myself.
The weird part is, there are a lot of people I know who played the same game, and invented it themselves as well. How the heck does a game like that get independently mass-invented? | 15 | You didn't invent it yourself. :-) Most kids get it from other kids and it's passed down in grade school. A younger kid might see their older sibling playing it or an only child will see their friends or neighbors their age playing a similar game. "Don't step on a crack or you'll break your mother's back!" is very similar. Since lava is cool (hot molten rocks!) to well...most sane people but especially little kids, pretending your floor is something neat rather than the boring carpet your parents are thinking of replacing is just fun. | 24 |
CMV: Meat and fish are not neccesarily unhealthy | I want to first start off by saying that this is completely separate from the ethical point of view, factory farms are of course absolutely terrible and I don't believe we can justify unnecessarily killing animals, that's why I myself am vegan.
I don't believe like some people that a vegan diet is unhealthy as this isn't reflected in the research, yes you can cherry-pick studies and take studies out of context to come up with the conclusion that a vegan diet is unhealthy, but we should look where the overall quality evidence points to. The largest organization of nutrition and food professionals, the Academy of Nutrition and Dietetics released a peer-reviewed statement saying: *" It is the position of the Academy of Nutrition and Dietetics that appropriately planned vegetarian, including vegan, diets are healthful, nutritionally adequate, and may provide health benefits for the prevention and treatment of certain diseases. These diets are appropriate for all stages of the life cycle, including pregnancy, lactation, infancy, childhood, adolescence, older adulthood, and for athletes."* [https://pubmed.ncbi.nlm.nih.gov/27886704/](https://pubmed.ncbi.nlm.nih.gov/27886704/)
So yes I do believe that vegan diets are perfect;y healthy, but I don't see any reason why it would be healthier than a diet consisting mostly of whole plant foods and then a bit of lean meat or fish. Not meat from an animal that is fattened up and can barely move because they aren't in the open field but in pens or cages, I'm talking about healthy animals, this is a tiny minority of the meat which is produced in the US, 99% of meat in the US comes from factory farms so the vast majority of studies comparing plant based diets vs predominately plant-based diets are based on this fattened up meat.
Vegans are generally more health-conscious, they exercise more, eat less processed junk, and don't consume cheese. For this reason, population studies often show that vegans have a better health outcome, so this type of data can't change my mind. What can change my mind is quality evidence that a diet consisting predominately of whole plants with a bit of meat and fish is unhealthier than a whole food plant-based diet. | 19 | >I don't believe like some people that a vegan diet is unhealthy as this isn't reflected in the research
Except a vegan diet CAN be unhealthy. Plenty of junk foods are vegan because plant matter and chemicals are cheaper than meat byproducts.
Every diet CAN be super unhealthy. It all depends how you approach them. | 33 |
[Marvel] How powerful is the country of Wakanda? | Can they be considered a global superpower? | 19 | No. The definition of a superpower is a state that is able to project power on a global scale. Wakanda is extremely advanced, but they have a small landmass, low population, an extremely weak military, and have made a point of staying out of global affairs. They could certainly punch above their weight class if they wanted to given their advanced technology and a near monopoly on vibranium, but tech and resources only get you so far in a world where there are gods walking around.
If Wakanda made an effort to get extremely involved in global affairs, I'd compare them to Japan. Extremely advanced technology, a highly developed economy, and the theoretical ability to be a far larger player than they currently are, but things like a long history of intentional isolation, a relatively small landmass, and a population that seems fairly content with maintaining the status quo keep them from ever reaching that potential, at least for a good while longer. Definitely a large player on the global stage, but far from a superpower. | 49 |
[Short Circuit] How would Number 5 have developed if he had access to the internet? | We see him devouring information from the moment he gains sapience. Billboards, TV, radio, encyclopedias. How would he have turned out if he had access to the internet, with all of it's wonders and depravity? | 38 | He'd have absorbed all the information he could much like Leeloo in Fifth Element. But when he got to the "war" entry in Wikipedia his eyes would start glowing red and he'd turn into a terminator. It's basic computer science. | 27 |
So, what are some legitimate scientific criticisms of or alternatives to evolution? | I was wondering if there are any **legitimate** scientific alternatives to evolution. Although I realise that 'Theory of Evolution' is a broad term, what evidence is there that does not fit nicely with - or even contradicts - evolutionary principles such as natural selection, genetic mutation, sexual selection, and the like?
EDIT: perhaps I did not ask a precise enough question:
What would cause a major revision to evolutionary theory? What findings do not fit well with evolution as we currently understand it? | 22 | There is no biological knowledge that does not fit cleanly into the theory of evolution. That is, the theory of evolution can be used to explain literally every piece of empirical data there is that pertains to all aspects of biology. | 57 |
[X-Men] If Wolverine were to stab an infected person, tuck away his claws, and then proceed to stab me, would I become infected with the same illness? | Okay imagine this, Wolverine stabs someone dealing with an infection like I'm not sure, the common cold or influenza. If he unsheathes his claws for a small period of time, then stabs me (to which I get medical attention and live), would I be dealing with the same infection as the first victim?
What about in a hypothetical scenario where the victim's blood stays on his claws at the time of sheathing and unsheathing and instead it's a blood borne illness? | 26 | No, with his healing factor curing him of gunshot wounds in seconds, a mere infection would be dealt with literally immediately. Also, hard metals like stainless steel don't carry disease well anyway so adamantium can be supposed to also be germ resistant. | 20 |
[The Office] Why does Jim never face any penalties for his pranks against Dwight? | So some of his pranks aren't that crazy like just showing up dressed as Dwight and imitating him, others can be really hard to trace back like putting quarters in his phone to make him bonk himself in the face after they're removed, but some pranks are just unquestionably unprofessional and pretty easy to trace back to Jim like moving Dwight's entire desk to the bathroom and acting smug about it.. Dwight is entirely right it's extremely unprofessional and severely impacting his ability to work for no reason. | 317 | Michael likes Jim. He would never penalize him, especially not for just playing a joke.
Dwight has gone to Toby with numerous complaints about Jim, but Toby never sends them to corporate. He just keeps them in a box under his desk. So Dwight really has no recourse left. | 453 |
ELI5: China has ceased stockpiling US Dollars.....What does this mean, and what are some of the effects we'll see, short & long term? | [The Article] (http://michaelsnyder.mensnewsdaily.com/2013/11/china-announces-that-it-is-going-to-stop-stockpiling-u-s-dollars/) | 327 | It's terribly complicated and economists are going to disagree quite a bit, but it's probably good news for everybody except for China's export industry. The big trends will be that US debt will get a bit cheaper, but given the US Federal Reserve Bank's policies, it will probably just gobble up those bonds that China chooses to not buy. The bigger part of the announcement is that this suggests that China is going to try increase the buying power of its currency, meaning that China's labor is going to get more expensive, but China's population will be able to buy more foreign goods, which is welcome news to producers in other places which would like to export more. | 109 |
ELI5: Why do sodas taste better in glass bottles and cans rather than plastic bottles? | 395 | One word friend: permeation.
So, plastic bottles are permeable as hell. They will lose water and CO2 over time. This will impact the flavor, how bubbly it is, and the “crispness” of the soda. Glass and aluminum are not as permeable so the formula stays relatively the same and doesn’t lose as much from permeation. On that note most plastic bottles are PET and it leaks like a sob. | 307 |
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eli5 Why are historical ruins so much lower than modern ground level? | I recently visited the Roman Baths in Bath. The tour made a point of pointing out that you had to go down several meters below the modern ground level to see the remains, that as you travelled down you were travelling further into the past. Walking around old cities you'll sometimes come across a glass panel in the road and below it you'll see the excavated original medieval road 1 or 2 meters down. How is it that this happens? I can't imagine it's a geological process in only a couple of thousand years. | 709 | Archaeologist here. There’s a lot of reasons. Some have already been mentioned. When buildings collapse it makes a lot of rubble and dust that can cover other ruins. You also have floods, volcanic eruptions, dust storms, etc. Other factors can be plants…over thousands of years plants grow on ruins, die, and decay and this produces a lot of soil that can bury things. People also often throw trash into abandoned buildings, over time this builds up and can bury a whole structure. Last, don’t forget deliberate burial in old cities. It’s easier to just fill in the foundations of an old structure with dirt and build on top of it, rather than tear the whole thing down. Same with streets, if you need to replace a street, just cover it with some dirt and pave it fresh on top. Over time this can add many layers on top of one another. | 876 |
[Spider-Man] How is Peter Parker not famous ? | Or at least not a well known Public Figure by now....
He's Dating a model,Works(or worked)for a popular
Newspaper, Has multiple connections and associations, with Spider-Man and companies, and has even owned his company... | 77 | He’s probably Google-able but pretty forgettable in a world with superstars like the Fantastic Four or the Avengers.
People would be like, *Mary Jane Watson has a boyfriend? Oh, he’s a photographer/failed entrepreneur. Fair enough.* | 98 |
[Ghostbusters] What would have been written in the Help Wanted Ad that the Ghostbusters put out? | Bonus: Who would have written it? What were the qualifications they were looking for? And why would it have been attractive to only Winston? | 20 | Ray would have come up with it (Egon would have been too busy and Peter probably didn't care enough to put any thought into it), but Janine would have typed it out and submitted it to the newspaper. It would have been stiff, formal and contained only the basic information and job description. It would have likely asked for someone with a PhD in particle physics, maybe some higher mathematics or at least SOME kind of high education. And the job description would have been full of wonderful terms like "observing paranormal phenomena" and "collecting postmortem samples for analysis". Most people would have assumed it was a joke or way above their skills, so they avoided the ad and went on to apply at different locations.
Winston just wanted to get paid and he assumed rightly that anyone who came up with such a ridiculous ad and interview would be desperate for help. He also didn't run when he found out everyone in the firehouse were completely serious, so he was hired. | 16 |
[Marvel] Can Magneto take the Infinity Gauntlet off of Thanos? | 26 | I feel really stupid that in all the various infinity gauntlet talk, I've never heard anyone bring up someone like Magneto that can control metal. Frick' SWOOP and now it's mine. Done.
I feel like if someone is actively using it, like Thanos shooting out Power stone rays, that would probably prevent it from just flying off, but yeah, if Thanos is just walking around with it on, they already showed you can literally just pull it off his hand, so there's no reason a magnetic user couldn't just make it fly off to them. | 27 |
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[DC/Comics generally]The Hulk can lift a mountain or drag together continental plates. But why doesn't the surface that he is exerting this tremendous strength on just snap, the mountain fall on top of him or the plates break from his grasp? How do other strong characters deal with this? | 28 | The 'Selective Field of Influence Theory' by Doctor Otto Binder
The theory was first postulated in reference to the exploits of the World War II era Captain Marvel, aka, Shazam. The World's Mightiest Mortal could punch a tank, and the power was applied only to an area the size of his fist. However, he could rescue a disabled plane in midflight by holding a wing, when that should have torn the wing off.
The theory is that these gifted individuals exert their influence as if they were manipulating a variable size and shaped field. Thus Captain Marvel can hold up a falling building, and later return to punch out a single brick. How this happens is not clearly understood, but it appears to be a widespread and innate attribute of these individuals. | 39 |
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Why is there a time-energy uncertainty relation when time is not an operator in Quantum Mechanics? | The Heisenberg Uncertainty Principle is based on the property of the commutators of two Hermitian operators. But time is not an operator in Quantum Mechanics, so what gives? How fundamental is this relation? Where does it come from and what does it mean? | 1,863 | It's not really the same kind of uncertainty relationship, since you are correct that time is not an operator.
Instead think more as a time evolution on states. If a state is an eigenstate of the Hamiltonian, it is stable in time. If a state is not an eigenstate of the Hamiltonian, it can be written as a linear combination of Hamiltonian eigenstates, with a time dependence determined by the difference in energy levels from the spectrum of the Hamiltonian. It is from this time dependence that the time energy uncertainty comes from. | 360 |
[Star Wars] What is the difference between Bacta and Kolto? | I'm playing through KotOR now and they seem to be pretty much the same thing? | 24 | Both are powerful healing agents, but they come from different places. Kolto was commonplace a long time ago, but Production suddenly grinded to a near halt, causing the Galaxy to turn to the more commonly availible bacta, which are in common use today. | 28 |
CMV: Exposure to Misinformation and Invalid Arguments is Crucial in the Exercise of Critical Thought | John Stuart Mill said it best when he argued 160 years ago, in his classic *On Liberty*, that it is impossible to truly know if 'x' is false if we refuse to hear any arguments or evidence purported to be in favor of 'x'. If, for example, a given society were to decide that holocaust deniers and anti-vax people should be fully silenced to the point that I never heard their reasoning, then I would not be in a position to know whether in fact their arguments were invalid. And since being able to compare arguments in order to determine which ones are valid or invalid is a part of critical thought, my opportunity to exercise such critical thought would be greatly diminished.
Potential Objections:
1. On several issues common sense or intuition can be used to arrive at the truth without the help of critical reasoning. Response: common sense and intuition are not infallible and thus need to be verified through the testing of evidence and critical thought. Many people have erroneously believed, for example, that it is self-evident that the earth is flat or that the sensation of color pertains to the objective world.
2. We've already heard enough to know that the holocaust deniers and anti-vax people are wrong. Response: that in itself proves the point that hearing such arguments is useful in determining what is true or false.
3. It is sufficient if others, as with previous generations or experts, hear those invalid arguments on our behalf in order to determine if they are valid or incorrect. Response: previous generations and experts can certainly do that, but if we ourselves simply trust them then we are merely conforming to their views rather than exercising critical thought or exhibiting genuine knowledge (on the assumption that having the correct view on the basis of conformity is not the same as knowledge).
4. It is for our own protection that we should not be exposed to misinformation. Response: perhaps so, but that does not relate to my view apropos of critical thought. It simply states that the harm outweighs the need for free speech and critical reasoning.
If I've missed something I'll add an edit. *But as a last point I will add that if my view is changed, then in a certain, perhaps ironic sense it would actually be proven, since it would show how a misinformed view grows into knowledge not through its censorship but rather through hearing a variety of ideas in the exercise of critical reasoning.* In which case I would be happy to change my view!! :)
​
EDIT: I forgot to clarify that while I believe that exposure to misinformation is crucial to the exercise of critical thought, it is not a sufficient condition of it. For example, if I am a deeply ignorant, uneducated person who is psychologically susceptible to propaganda, then being exposed to bad ideas won't by itself suddenly make me a critical thinker! But, nonetheless, if I am to develop into one then at some point I must be able to analyze bad information. | 135 | Misinformation that is presented critically is helpful in exercising critical thought. There is plenty of misinformation out there that can be analyzed and dissected, and there always will be. Misinformation that is spread widely with no context to masses of people with little to no critical thinking ability on the other hand is dangerous to critical thought. | 48 |
CMV: I'm racist |
I just realized I'm racist. I was having a great time with this girl at a bar, and when I went to the restroom, upon my return, she was dancing quite sensually with a black guy. It made me so irrationally mad that I called over several of my friends to jump him. Nothing actually happened, as they realized the whole thing was stupid, but the whole thing made me realize that it made me so much angrier because he was black. I had never thought of myself as a racist- I worked for Obama before he got the nomination in 2008, and I've always thought of myself as being very progressive. I'm still quite drunk, and Reddit, please help me change my view.
>(http://www.reddit.com/r/changemyview/wiki/rules)***. *If you see a comment that has broken one, it is more effective to report it than downvote it. Speaking of which,* ***[downvotes don't change views](http://www.reddit.com/r/changemyview/wiki/guidelines#wiki_upvoting.2Fdownvoting)****! If you are thinking about submitting a CMV yourself, please have a look through our* ***[popular topics wiki](http://www.reddit.com/r/changemyview/wiki/populartopics)*** *first. Any questions or concerns? Feel free to* ***[message us](http://www.reddit.com/message/compose?to=/r/changemyview)***. *Happy CMVing!* | 55 | You needed a reason to hate him so you made one up. You didn't know the guy, so his appearance is all you had to go on. If he was a white guy wearing tight jeans and thick rimmed glasses you would have gathered your friends to jump a "hipster". | 137 |
How is having such dependent offspring selectively advantageous for humans? | 34 | Well, first of all, humans are extremely K-selected in comparison to most mammals. We put a lot of effort and care into each individual which is born. You can have a supremely dependent offspring when you put a lot of care into it. Additionally, our babies are born in what we call a secondarily altricial state. We are less developed at birth than what you'd see in most primate species. Basically, we are born before you would be expected with regards to our brain (and body) development. Much of this is related to brain size. We are born relatively large-brained, but have neonatal brains that are in a less developed state (relative to final brain size) than seen in our primate relatives. It has been hypothesized that this is due to the "obstetric dilemma," where you can only manage to squeeze out a head of a certain size through the pelvic outlet (although there are some researchers who indicate that this might not necessarily be the case).
It is also interesting to note that humans are really good at taking care of our kids after they are weaned. Most primates do not engage in significant direct care of offspring following weaning. Primate juveniles are pretty much on their own in terms of finding food following weaning -- and have correspondingly high rates of mortality. In contrast, humans engage in significant food sharing and direct care for individuals after weaning. This period called "childhood" (see work by Barry Bogin and friends) not only increases offspring survival, but also reduces interbirth interval by lowering the amount of time spent in lactation. As females demonstrate reproductive suppression during lactation, reducing this period allows us to resume cycling faster and allows us to have additional kids while still having dependent offspring. In contrast, other ape species have extremely long interbirth intervals as their period of lactation (and thus reproductive suppression) is longer than found among humans.
| 43 |
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How efficient are our solar panels? | 17 | The commerical panels available on the market are ~15-19% efficient with sunlight. Lab ones are in the 20% region The theoretical limit for single junction silicon solar cells using sunlight is about 33.7%, based on the solar spectrum and the bandgap of silicon.
Multi-junction solar cells made from multiple layers of material offer better theoretical efficiency as you can tune each junction to a given wavelength. Certain organic semiconductors that can generate mutiple charge carrier pairs from a single photon also offer better theoretical efficiency, as you can better use the higher energy photons rather than just making heat. In the lab, multi-junction cells have hit ~45% efficient, but these aren't commercially viable. | 12 |
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Is there a specific reason why many people's arms tend to hurt after receiving a flu shot but not after many other shots? | 26 | There is a substance called Adjuvant that is an irritant included with some shots. Adjuvant stimulates your innate/non-specific/general immune response, by stimulating your innate immune response at the same time as the vaccine stimulates your specific/late/anti-body/adaptive immune response the adaptive immunity developed is stronger. | 14 |
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ELI5: Why home blood tests do not exist, while we can measure our sugar levels with personal devices at home? | I feel like going to get basic blood test done is a chore. Why it can't be done at home? I have the glucometer at home and its great. Is the same thing possible for a more general purpose? Education-wise I am far from anything to do with medicine, but technologically speaking, is it really a stretch?
Having a nurse come over is not what I mean by at-home testing, btw.
English is not my mother tongue, sorry if my question is not clear.
Edit: Yes, I missed most of what's going on with Theranos. It's not widely covered where I live, I will definitely watch the documentary or listen to the podcast. sounds interesting!
Also, thank you all for your comments, so much I didn't know! | 6,885 | Most tests don't use blood per se, they use serum or plasma. Hard to get at those at home.
A blood count requires machines able to see, differentiate and count a variety of different cells in your blood. It is not comparable to a glucose test. | 2,792 |
[Star Wars] Why do the Separatist bother with life support on Droid controlled ships? | It seems like an unnecessary drain on power, and a lack of life support would make it that more difficult for organic boarding parties. | 35 | Because sometimes they need to take prisoners or shuttle officials/organic officers around. And they never know when a prisoner might come by.
Better to be prepared. In any case, if they didn't use that, boarding parties would soon start using space suits. Clone Trooper armors already give them over fifteen minutes of air in a vacuum. | 41 |
CMV: I believe stopping a fetus before it becomes a baby, is no morally different from never creating it in the first place. | A fetus is a potential person, and when a woman has a abortion shes removing the chance of the fetus becomming a person.
Inside every woman (well close) there is a potential life. If you choose not to get pregnant, then you are not taking the life, you are simply not creating it.
Also, I would appriciate if you try to stay objective, and that you dont quote any religious book unless theres evidence to back it up.
tl;dr: Stopping a fetus from beeing born is no different from never creating it in the first place.
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> *Hello, users of CMV! This is a footnote from your moderators. We'd just like to remind you of a couple of things. Firstly, please remember to* ***[read through our rules](http://www.reddit.com/r/changemyview/wiki/rules)***. *If you see a comment that has broken one, it is more effective to report it than downvote it. Speaking of which,* ***[downvotes don't change views](http://www.reddit.com/r/changemyview/wiki/guidelines#wiki_upvoting.2Fdownvoting)****! If you are thinking about submitting a CMV yourself, please have a look through our* ***[popular topics wiki](http://www.reddit.com/r/changemyview/wiki/populartopics)*** *first. Any questions or concerns? Feel free to* ***[message us](http://www.reddit.com/message/compose?to=/r/changemyview)***. *Happy CMVing!* | 54 | I totally agree, but the first thing anyone would say to counter this or question you on this is "where do you draw the line?" so perhaps you should add that to your post. Because it's a valid question. Where *do* you draw the line? You're saying a fetus the minute before it's born is a potential life, and the minute after it's born it's a life-life, and it's okay to abort it up until the minute it's born and/or you're claiming that up until the minute it's born, it's no different than an unfertilized egg in a woman's ovaries? Or if that's not what you're saying, please clarify. | 16 |
[The Thing (1982)] What happens to the clothes when The Thing devours you? | Many characters get devoured and imitated in The Thing (1982). I have always wondered about the clothes.
Bennings has his coat, pants and sweatshirt on, they are not bloody, not ripped, they look perfectly normal. The imitation is not ready yet, but clothing is not an issue in that case.
The characters at one point are assuming that it rips off your underpants - but why only the underpants? What is happening with the rest of the clothes? Suffice to say that the characters don't know anything for sure, they are just speculating.
Anyone has a working in-universe explanation? | 34 | I've always assumed that the thing absorbs any natural fibers, discarding anything it can't assimilate, and then remakes the clothing out of itself. The same way it made fur when it was the dog or hair when it's human. | 17 |
CMV: I'm glad that Pirate Bay was brought down. I see no moral justification for piracy of modern movies and games. | The most upvoted comments concerning Pirate Bay always hold it to some impossible level of importance. It comes across as people thinking that piracy is justified because big studios charge too much money for their goods.
I understand that Piracy can force the market to adapt in order to lower prices or allow for easier access, and this leads to the birth of Steam or Netflix. What I don't understand are the people that hold it as some sort of right to have access to anything and everything at no charge simply because they have an internet connection.
There is no situation where I would illegally download a move that was just released in theaters (or before it was released). That is flat out stealing, and harms the industry as a whole. There is also no situation where I would pirate a recently released game for the same reason.
Further, the argument of "They don't deserve my money" that people always throw around concerning the likes of Ubisoft or EA is an incredibly idiotic argument to justify piracy. If there is a product by a company you want to consume then purchase it. I don't agree with the human rights violations that happen in China or Bangladesh, but that doesn't mean I'm justified to steal the products produced there in lieu of boycotting them.
I feel like I should add as an addendum that there is one situation where I have thought it was justified to pirate a movie, and would have if I had been able to. My father was bedridden while fighting Lung Cancer and wanted to see the second Hobbit. There was no way he could have sat through it at the theater, and we knew he wouldn't be around long enough for a DVD release. That is such an extreme case though, that I hard think that it can be used as a justification for the existence of the Pirate Bay.
Edit: Discovered that we're having car problems this morning (x2) so I may not be around to respond for a couple hours, but I will!
Edit 2: Also glad that every comment I make, though being substantive and contributing to discussion, is getting downvoted. Read [redditquette](http://www.reddit.com/wiki/reddiquette), the side bar, hover over, and footnote included on every CMV op...
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> *Hello, users of CMV! This is a footnote from your moderators. We'd just like to remind you of a couple of things. Firstly, please remember to* ***[read through our rules](http://www.reddit.com/r/changemyview/wiki/rules)***. *If you see a comment that has broken one, it is more effective to report it than downvote it. Speaking of which,* ***[downvotes don't change views](http://www.reddit.com/r/changemyview/wiki/guidelines#wiki_upvoting.2Fdownvoting)****! If you are thinking about submitting a CMV yourself, please have a look through our* ***[popular topics wiki](http://www.reddit.com/r/changemyview/wiki/populartopics)*** *first. Any questions or concerns? Feel free to* ***[message us](http://www.reddit.com/message/compose?to=/r/changemyview)***. *Happy CMVing!* | 19 | Every file downloaded from the pirate bay is 100% legal to download. The files you download from TPB do NOT contain any copy written information. They are torrent files and simply contain information on how to download other files (which obviously may be illegal).
TPB does not police what files you are being linked to, they think it is not their job to be moderators of the bulletin board they have posted on the internet. Content companies (Ubisoft, Time Warner, HBO etc) feel that TPB should spend time, money, and resources policing this to protect their (content companies) profits, without offering any compensation to TPB for this besides saying we will sue you if you don't do this.
TPB is a bulletin board that allows users to post and see whatever they want in an unfiltered manor. It is honestly no different then Google in many ways. Why should a company in a different country be able to tell you what you can and can't let users post when the service you provide is specifically an unmoderated one as a feature. | 17 |
[Rocky Horror] Giving myself over to absolute pleasure sounds pretty cool. What's the down side? | I'm cool with living my life for the thrills. | 18 | Pleasure fades like the high of a drug. What gave you joy will soon fade. You will crave for the same feeling you once had but must now go to greater lengths to achieve it.
Your life will degrade into the never ending pursuit of pleasure. You will become its slave - its darkness will consume you.
The extremes you will go to for the slightest bit of pleasure will make you a monster beyond reckoning. Eventually there will be nothing left but an empty shell, devoid of all things good, a demon of lust whose thirst cannot be quenched.
Your hunger will become your hell. | 34 |
When an avocado is not ripe, are the fats and nutritional content just as present or does the ripening process make them available? If so, why? | Here I am sitting with a bag full of avocados, and all of them are not quite ripe yet. I wonder if the fat and nutritional content are the same at this stage as when it ripens or if there is a type of transformation that happens as it ripens. If, so, why? | 1,978 | The nutritional content is all still there, but the nutrients in unripe fruits are more difficult to digest for us, and hence they don't taste as good. Starches breaking down into simple sugars, complex enzymes denaturing into amino acid chains, all this helps us digest and absorb the nutrients easier. This is also the same reason we cook meat vs eat it raw (aside from the chance of infection). | 1,168 |
ELI5: Why do so many people have peanut allergies? | Just saw on the news that a trial was happening in NZ which could lead on to a cure for peanut allergies, and it made me realise that many people around the world all have this common allergy. I guess my question is, why is it so common? It's interesting enough to know that it is widespread, but knowing why would help me make sense of it all. ELI5. | 29 | Nobody's sure. It's more common in developed countries which has led to the ***hygiene hypothesis***, which is basically that our immune systems like to pick fights, and will attack random substances if they can't find real infections - even if they're delicious and harmless like peanuts. | 18 |
Eli5 - how can people not snore laying down while awake but then snore as soon as they fall asleep | I know head position and all that affects snoring but how can someone be awake and laying down and not snore, but then fall asleep in the same position and then start snoring | 78 | When a person is awake, they have full control over their muscles. When a person is sleeping, most of the muscles are relaxed. This includes the muscles that keep airways open. When a person with the 'correct' anatomy sleeps, their airways partially close leading to snoring. The extreme end of this is sleep apnoea, where the airway closes completely. | 102 |
[Spider-Man] Do you think Raimi Spider-Man could've engineered his own web shooters if he really had too? | Compared to the other two on screen spider-men he seems to be the least technologically inclined. His suit is definitely the least advanced and in the trilogy we rarely get an inside look into his scientific expertise. | 66 | Spoilers for No away Home
>!In his own movies Peter is a gifted scientist to the point that he found an error in Doc Ock's calculations for the fusion reactor. Then in No Way Home we see that he was capable of creating a cure for the Green Goblin in a matter of hours. So he probably could build webshooters if he needed to.!< | 100 |
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