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ELI5: Why do atoms of a same radioactive element decay at different times? | For example uranium-238 has a half-life of 4.468 billion years, which means that one uranium-238 atom decays in a day and another one in one billion years.
Why do atoms of a same element have so vastly different "lifespans"? | 29 | Radiodecay is random.
Picture it like this:
The atom is rolling a random handful of dice once a second. When all of them come up sixes, the atom blows up.
This may happen on the very first roll, or it may take all day.
Atoms with very short half lives are unstable - they’re barely held together and you only need o... | 60 |
What is the soft "crackling" sound my car makes when it's cooling down after I park it? | I don't know how to describe the sound exactly, but it's a very soft "crackling" or "clicking". Does it have something to do with the metal around the engine or hood contracting as a result of cooling down? | 666 | As different parts of the car cool, the metal contracts at different rates. This creates tension within the metal, which accumulates as the car cools further and the temperature difference increases. Eventually, one part may move quickly to release this stress, which creates an audible 'tick' sound. | 370 |
[Watchmen] What is Dr. Manhattan is capable of and is there a way of defeating him? | 21 | Ozymandias had it right. Dr. Manhattan was human, and despite his abilities still thinks like one. Granted, as time passes his perception of time, space, matter, and everything else diverge from how humans perceive the universe; however, he is susceptible to many of the same emotional weaknesses as humans. If you're ab... | 25 | |
[Star Wars] What if a Mandalorian debt becomes impossible? | So after watching the Mandalorian, I notice there is quite an abundance of debts going around, and Mandalorians take these things seriously.
However what if an agreed repayment of a debt becomes impossible? Like "I will help you rescue an individual" and then before the rescue is performed, said individual is executed... | 203 | Then the debt gets carried on to some other task. It's subjective but mandos are extremely honorable and won't renege on a debt just because of technicalities. So long as the debt holder lives or has given a task that is still viable the indebted will have something to do even if the original task has changed. It's onl... | 150 |
[Superman] How does Kryptonite compare to earthly minerals in hardness? Does it have any practical uses outside of Kryptonian deterrence? | 23 | I've never ready anything about it being particularly durable, sharp, or anything else of interest to material scientists. It is radioactive, however, and can be used as a power source, as several of Superman's opponents have done.
It's also fantastically expensive, which means there's *some* sort of a demand for the ... | 22 | |
Can you know something without having it memorized? | Like you know it in some contexts (like when you see or hear it and recognize it) but not others (like when trying to solve a problem or trying to communicate something). I haven't really seen anything written about this so I think its worth discussing. | 20 | There's some interesting work about it in Husserl's *Ideas II*, near the beginning, as well as in his *Origins of Geometry*.
Basically, Husserl has the idea that one you learn something, it can become the grounds for something else that you learn. Let's say, for example, that you learn special relativity to read a boo... | 21 |
ELI5: Why can I pick up my little brother, who weighs around 100 lbs with no issues, but I struggle just trying to get a 50 lb weight off the ground? | 1,130 | A big thing to remember is that when you pick people up, they are actually helping you. When picked up, people uncounsciously shift around to get their center of balance just right so they wont fall, and it helps out the lifter.
If you tried picking up an unconscious or asleep (or dead) person for example, you would h... | 1,241 | |
I don't understand why Iron is the element that starts the supernova process? (Layman's terms please) | What property does Iron have the kickstarts a supernova? Why not another metal? I just had someone breifly describe to me how a star's lifespan works (Fusion, going from one element to another down the line) but I can't find out why Iron is the magic element. | 559 | I think it is misleading to think of iron as "kickstarting" the supernova process. When you burn a log, the wood turns to ash. When you have no wood left, and only ash, the fire goes out. But the ash didn't cause the fire to go out - the ash is there because the fuel is gone.
Similarly, stars need fusable atoms as ... | 678 |
How would a springboard work on Moon? | I've been wondering about this for quite a long time. None of my physics teachers could tell me how would be the effect.
The gravity on the Moon lets us to bounce 6 times higher, but reduced falling speed would reduce the pressure put on the trampoline surface by our body. So, how would it be? | 65 | First: ignore the fact that it's notoriously difficult to do acrobatics on the moon. And friction.
To figure this out, we need to look at energy. When you jump, you add kinetic energy to yourself. This is converted into gravitational energy when you move up, slowing you down. As you fall back, the reverse happens and ... | 18 |
ELI5: Why do deodorants say "Apply to underarms only"? | 26 | Gabrielpenfield brings up an interesting scenario, but it isn't the main reason why we don't apply deodorants everywhere. Deodorants simply block odors, so we, for the most part, can use them everywhere (I wouldn't use them on your face in case of acne, though). However, the real danger lies in anti-perspirants. The... | 14 | |
[Flavortown] How do the residents of Flavortown view Guy Fieri? | Is he seen as some sort of tourism ambassador, or a self promoting huckster? Does he actually follow through on these promises to take people there in the first place? | 221 | He is Flavor Town's god, devil, servant, master. He is the mewling cry of its newborn babes and the gasping wheeze of its dying patriarchs. He is the bones on which Flavor Town is built, and when Flavor Town returns back into nothingness at the end of all ages he will be the one to sing it into the void. He is the ferv... | 165 |
CMV: The TPP is the only way that America can sustain its economic hegemony over east Asia, and is necessary if it wants to remain a world power. | As China begins to overtake the US economically the biggest threat to world peace would be if the US loses its overwhelming market power.
Peaceful solutions to for the Iran crisis, for example, will be impossible if the US, and just as importantly its sphere, is unable to impose crippling sanctions.
The TPP is a fre... | 90 | The TPP is far from the only way that the US ould maintain hegemony in Asia. There are multiple other deals that could be made, either economically or diplomatically, that would increase hegemony and our overall popularity in the area. For example, a grand bargain with China where we give up our defense of Taiwan in re... | 30 |
Do stars undergo orbital decay in relation to the center of a galaxy over extremely long periods of time? | In a way comparable to a satellite would fall back to earth after several years in orbit | 37 | Satellites fall towards Earth due to drag from the latent amount of atmospheric gas in their orbit. This is not an issue for stars. There is theoretically orbital decay from gravitational radiation, but in practice it would take longer than the lifetime of the universe to notice this effect. | 10 |
[MCU] How did Titan die? | First of all, I’m sorry if this question has been asked before but I’m not very active on the sub so I don’t know some posts. If this has been asked before, then could someone please link to me to the post, thanks. Also, sorry for formatting, I typed this on my phone.
Alright, so Thanos claims that overpopulation des... | 17 | Titan may have been a spacefaring civilization, but it might not have developed interstellar travel yet. Ecological disaster is gonna get you, if the only places you have to go are nearby barren rocks.
Which leads me to overpopulation. Too many people, consuming too many non-replenishable resources, can kill a plane... | 22 |
Will we ever get a probe or even better a human to the centre on the Earth? | If so what would we find there? Would loads of pressure be released causing mega eruptions or send the earth flying through the solar system like a burst balloon? | 19 | I work on camera systems that go on vehicles with depths ranging from 100 m to 4 km in the ocean... For 100 m, we get to work with nice easy materials like aluminum (6061 is popular for its corrosion resistance). For 4 km, we need pretty fancy pressure housings made out of a single titanium crystal (something like Ti-6... | 20 |
[LOTR] Why did Gandalf call the Fellowship of the Ring "fools" in "fly, you fools?" | Did Gandalf believe the Fellowship was not intelligent, at least during that moment? | 31 | They were standing there, staring at one of the very few entities on the planet as powerful as Gandalf himself. Essentially, they were facing down a fallen Archangel.
He was trying to convey that standing there, or trying to help, was dumb. There was nothing they would be able to do to help. Running meant a chance at ... | 235 |
ELI5: What makes our sides hurt when we run? | 87 | Overusing intercostal muscles and not controlling the diaphragm when running. Intercostals and the diaphragm cramp easily when running because they're either not used or passively used all day. Consciously using you diaphragm can help. Not an expert just an athlete | 57 | |
Why do professors ignore letter of recommendation requests instead of just declining? | Is it a sign that they simply forgot to reply or missed my email, or is it that they just can't be bothered to reply at all if they aren't interested?
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**Edit:** When I make requests in the future, would it be appropriate to tack on "just a simple yes or no answer is fine" at the end of the email, to hint... | 173 | No, tacking that on would be passive aggressive.
And it's often because the email was lost in the neverending flood of other things, or because it's easier to ignore than deal with the response to a no.
Send a single, polite followup or ask them during office hours. If no response then, head elsewhere. | 182 |
My spark is gone | I recently had a realisation that whilst I enjoy the concept of a PhD, I really don’t enjoy the actual work. I’m in my first heard all I’ve done so far is work from home. I haven’t even physically met the people in my department or the other PhD students.
Try as they might, I simply can’t garner the same enthusiasm a... | 154 | First question is whether this is likely to change with a return to being face to face?
The answer to that isn't necessarily straightforward though - a PhD is by its nature a pretty solitary thing. Having people around you in an office can make it a lot better though. Also, a PhD is less about learning, and more about... | 70 |
ELI5: How is it that Aaron Sorkin could make movie about Mark Zuckerberg(The Social Network) and movie about Steve Jobs without the approval of the person or family and not get sued | 22 | You can't copyright facts about a person's life story. Mark Zuckerberg doesn't own the events of his life, they're things that happened. Steve Jobs' estate doesn't own the events of his life, they're things that happened. If Zuckerberg or the Jobs estate think that Sorkin is maliciously misrepresenting the facts, they ... | 20 | |
We have microwaves to quickly heat up food or drinks - why don't we have a device to quickly cool something down in a similar manner? | I've always wondered why I can stick a cup of water in a microwave and heat it almost instantly, but the best I can do to cool it is stick it in the freezer for a while and wait for it to cool down. Why isn't there a device to do this more quickly? | 17 | There is a kitchen instrument called the blast chiller that will cool down foods very quickly. Creating cold takes much more energy than to create warmth as well, limiting the general appeal of such a product that would not be used much. | 19 |
[ATLA] Have there been Avatars in the past who have been under the control of groups like the red lotus ? | I was rewatching ATLA and LOK it made me wonder if there were avatars who were kidnapped or coerced into fighting four them. Would something like this even be possible? Love to hear your thoughts. | 42 | Probably not, as the avatar state makes it extremely difficult to hold one, and each avatar is probably less powerful than the world around them due to advancing technology. The ability to throw fire is a lot more impressive compared to a wooden spear then it is compared to a giant laser mech.
Plus, an avatar would po... | 35 |
[SW ROTJ] If Jabba liked Captain Solo where he was why did he allow him to be defrosted and mess up his whole display piece set up? | 17 | If Jabba is anything, he is a self indulgent, hedonistic, sadistic bastard. Sure he would have been very happy having Han frozen in Carbonite for all eternity, but the moment he figured out that something was up and that Bounty Hunter with the therman detonator isn't who they claim to be, he wanted to see how things tu... | 25 | |
ELI5: how do bears manage to keep their muscles strong after hibernation? | I just thought of it because humans can barely walk after a lengthy coma | 101 | Nobody really knows, and it's only actually been quantified recently. Humans, as you noted, do lose strength relatively quickly, losing 54% of their strength in 90 days of bed rest, even with a well balanced diet. Bears on the other hand only lose 29% of their strength after 110 days of hibernation, so without any fo... | 107 |
[Dc comics] How come people think Batman is a legend but then he appears publically when the JLA give conferences? | In many iterations, people talk about a "bat" man that does not exist at all. But in other issues we have the same man appearing next to the big 7.
In JLI run, Batman publically stops a terrorist. But then? They want to interview him. Years later, the bat is still considered an urban legend and he even scared off repo... | 489 | > In many iterations, people talk about a "bat" man that does not exist at all. But in other issues we have the same man appearing next to the big 7.
I guess perhaps there's a disconnect between the two. On the one hand, you've got a guy who drives a space ship, lives on a space station, has a laser pointed at Eart... | 365 |
[Pulp fiction] Was Jules able to leave Marcellus Wallace's organization safely? | Was Jules able to leave Marcellus Wallace's organization safely? True, in the chronologically later episodes we no longer see him, but it could also be because he was killed.
Usually criminal organizations do not take the resignation of an affiliate well. | 18 | When Jules told Vincent he was quitting the life, Vincent didn't seem too concerned for his safety, just for him ending up a bum. Marcellus also appears to be the kind of person that if you do right by him, he'll do right by you. He even let Butch go when he saved his life. Jules is also very obviously not a wildcard a... | 55 |
How come metal sparks in the microwave yet the insides of microwaves are made out of metal? | 2,431 | Roughly: the microwaves induce an electrical potential in the object metal, this causes sparks as differences in the potential across the object metal causes arcs of electricity (especially with water vapour that may come from the cooking food). The side walls of the microwave are earthed, so any potential induced by t... | 811 | |
What actually is Critical Theory? | It seems like it’s become a buzzword recently but I very often hear conflicting politicised definitions. Upon doing a quick google of the term I can’t say I found a consistent or understandable (at least for me) definition.
It often seems to be used in the same breath as other buzzword like identity politics or neo-se... | 149 | Nope I'd say that's pretty good as an initial definition. But some context might help. In the first instance 'critical theory' was a school of thought that emerged in Germany in the 1930s in response to dissatisfaction with orthodox Marxism. Max Horkheimer and Theodore Adorno were early important figures here in the so... | 83 |
ELI5: If freezing generally damages tissue, how are we able to freeze human eggs and embryos for birth later? | 304 | An egg is literally a single cell that can instantly freeze. This limits the damage that ice crystal formation does.
Tissues are vastly more complex and therefore vastly more susceptible to damage with way more points of failure. | 293 | |
I believe that a woman who has gone through an abortion(s) cannot justifiably be anti-choice. CMV! | Recently, I have heard a lot about the abortion debate following the Texas legislation that was passed. I have seen several comments and statements from women saying that they once had an abortion but are now anti-choice. This argument simply boggles my mind.
I understand if the person disagrees with abortion in and ... | 20 | While you're correct that if someone performs an act that they themselves oppose, they are being a hypocrite, being a hypocrite does not mean that someone is wrong or that their stance is less valid (it's also tu quoque to make that argument).
For example, someone can make a completely sound and reasoned argument as... | 16 |
CMV: I am a Democratic Socialist and an Anti-Capitalist | I believe that democratic socialism is the best ideology for a country to possess. It's politics and programs should be revolved around it. Capitalism doesn't work, and therefore I oppose it.
* Democratic Socialism frees the people from the capitalist enslavement.
* Socialism gives everyone an equal opportunity in l... | 16 | The problem with your stance is that your chosen system removes the only thing that has ever worked with human beings - the incentive system.
To refute a specific point-
>Capitalism therefore believes that only those with money are those that matter to society, and everyone else are mere slaves.
This is in... | 18 |
CMV: The system of Significant Figures that we use in most sciences is an inherently flawed system. | As we learn in science classes, it is important to know the precision of our measurements, and it is important to know the difference between exact numbers and measured numbers. The scientific world keeps track of numerical precision through a system called "significant figures". Some classes beat students senseless wi... | 16 | There's two relevant factors you want to look at. One is the percent that a measurement is off by, the other is the absolute amount.
If the measurement is 1.1 mm, it can be off by as much as 0.1 mm, or 10% of the length. On the other hand, if it is 1000.1 mm, it can only be off by 0.01%, even if the absolute error... | 24 |
Is there actually a solution to the twin paradox? | All the ones I've come across assume that the twin on the rocket is the one changing velocity, (accelerating) which breaks the symmetry, causing him to come back younger. The whole point of relativity is that there are no preferred frames of motion. (each twin would have the same right to claim that it's the other one ... | 3,085 | It is not really a paradox. It just appears to be one, but on a closer look there is nothing paradoxical about it. It just doesn't follow our everyday intuition formed at low relative velocities.
> In general relativity it's not only the apple that falls to the earth, but the earth that falls to the apple. Both poi... | 1,812 |
[Power Rangers] Why do Rita, Zedd, Divatox, et al only create one monster at a time? Surely they'd have better luck if they made an army? | Also, imagine if the monsters were teamed up so that they had synergy with each other. | 29 | The bad guys only have so much ninjitsu they can shove into their monsters at any one time. If they made two monsters, then each of those monsters would only be half as effective as a single monster. Spread out that ninjitsu too thin and you've basically turned your monsters into fancy-looking mooks. | 35 |
[Warhammer 40K] How fast is warp travel? | Ideally, I would like to know how long it would take for a vessel with a good warp drive to cross the galaxy. | 31 | It seems random, honestly. The ships have to ride the waves of psychic energy like a ship in a storm. Some voyages cross the galaxy in weeks (such as when Chaos had the aid of the Gods) and some ships become permanently stranded (again, if the Gods see fit, like when Nurgle struck down the Death Guard). Best case sc... | 26 |
[Portal] How did Aperture stay in business for so long? | Even if you remove the truly insane death toll from their seriously dangerous, unethical, and possibly illegal experiments on humans, they still had to deal with the fact that, in no particular order:
* They continually failed to turn over any profits from their inventions and products,
* They were in blatant violatio... | 15 | Through the Perpetual Testing Initiative Aperture Labs discovered an alternate universe literally made of money. All USD too. None of that peso crap. Less fortunate versions of Aperture got their money from Cave Johnsons vast real estate empire and a handful of U.S defense contracts throughout the 50s and early 60s. | 33 |
ELI5: What does it mean when a scientist says ‘per second per second’? | 33 | It means that the rate of change itself changes.
"meters per second" is speed - the rate of change of an object's position. "meters per second per second" (m/s^(2)) means the rate of change of the object's speed, i.e. acceleration.
If a car is accelerating at 10 meters per second per second then it means that every ... | 55 | |
ELI5: Why does a deep scrape on elbows/knees/shins stay white for a period of time before bleeding? | Say when you dive into a pool and scrape your knee on the bottom, why does it stay white without much blood for around 30 seconds before properly bleeding? | 259 | This is because initially after an injury, blood vessels contract in order to minimise blood loss. They increase again in diameter later to facilitate healing and the movement of specialised cells and materials towards the site of injury. You can see this contraction and subsequent dilation of blood vessels anywhere; t... | 138 |
If a knife cuts your finger, what is stimulating your pain receptors once the knife is gone (after the cut has been made)? | Obviously, a cut still hurts long after your skin is first broken, and I am wondering why this is. Are nociceptors just programmed to keep firing for a specified time after receiving a strong stimulus? | 422 | Cell damage is one of the big ones.
When a cell pops open, it releases stuff (e.g., endothelin, bradykinins) that shouldn't be outside of the cell. This stuff hangs around and causes pain.
Another factor is the arachidonic acid pathways. In response to damage, cells will start to convert membrane lipids into things... | 466 |
[Escape from New York/LA] What event specifically caused Snake Plissken to go from war veteran to hardened criminal-turned anti-hero? | There were many ideas presented like distrust of the government after the Leningrad Ruse or his parents dying at the hands of the US police force, but what really broke him into the badass in the movies?
Also, being a veteran, could he have been eligible for government programs to help him get legit jobs, or did that ... | 25 | Snake lives in a world without good guys. In his universe, crime rates continued to skyrockets in the 1980s and 90s rather than decline. This prompted ever more authoritarian politicians getting elected with "tough on crime" platforms, legitimizing an aggressive, militarized police force.
This also led to an increasi... | 23 |
How do European drug manufacturers make a profit? | I was reading up on US drug manufacturers with U&C pricing, PBMs, insurance, patents, and the like, and even though all that what I couldn't wrap my head around was how EU drug manufacturers make profit with, and I could be wrong on this fact, their government setting a cap on drug prices.
Wouldn't a market cap di... | 58 | Drug companies patent things everywhere and sell globally. US is the biggest market so thats where drug companies make the most money regardless of nationality. There are different patent rules around the world so they have different monopoly timings, but as said Drug companies sell on every market regardless of where ... | 41 |
CMV: Miley Cyrus should not be judged for her lewd or edgy behavior. | I was prompted to post this after seeing a different post about Miley Cyrus being slutty on stage that hit the front page of Reddit.
https://www.reddit.com/r/WTF/comments/56sj86/miley_loves_her_fans_xpost_from_ronstagegw/
She certainly was being slutty on stage, sure, but I don't see why that's a problem at all. I re... | 16 | I think the point of her persona that is probably an act NEEDS to be judged to become successful. You don't get to enjoy the fame that comes with the behavior without attracting those who want the same sort of attention. She wants to be judged, needs it. Otherwise she wouldn't be posting what many consider to be smu... | 10 |
[Dc/Marvel] What are some purely offensive uses of teleportation powers or other uses of a teleportation power that's never explored or that they could theoretically do with their powers? | 34 | Nightcrawler's teleportation puts a lot of pressure on you. He's been known to grab someone and port with them multiple times to knock them out (he himself is used to it).
An alternate version of him once teleported someone's head off, so the regular Nightcrawler could presumably do that if he wasn't a nice guy. | 42 | |
ELI5: Why does it take so long to transfer files across hard drives? | I know certain things can contribute to speed. But I'm curious, why should 50GB of data take hours to transfer, when 1GB only takes a few seconds? | 32 | okay.. this is the correct answer..
a single file moves much differently then a bunch of files.. a one gig file will move immensely more faster then 100 different 10 meg files
same goes for a 1 gig file and 50 1 gig files or even one 50 gig file that is spread across multiple sectors on the harddrive making up smalle... | 16 |
[Mad Max] Why does Max seem inclined to constantly wander the apocalyptic wilderness, instead of settling down in one of the decent-by-comparison communities that he runs across? Sorry if it's something to do with his character archetype that totally goes over my head | 405 | He is haunted by the death of his family. He wants to stay alive but also wants to avoid attachment. The cop in him still wants to help when he can, but he tries to avoid those situations. The movies we see are just when he gets caught up in helping. | 540 | |
Eli5: Why are human bites so nasty? I know there are lots of germs in the mouth, but how can they be so much more dangerous than most animal bites? | 15 | Simple: the bacteria and viruses (mostly bacteria) that live in your mouth are pre-adapted to living in humans, and only *some* of the germs in, say, a dog’s mouth can cross the species barrier. The end result is that even though we have about the same amount of germs in our mouths as animals do, the amount of *infecti... | 37 | |
[Harry Potter] What happened to Fred’s hand on the Weasley clock? | Mrs. Weasley’s clock showed everyone’s current status; (Home, Traveling, etc)…. after he died during the Battle of Hogwarts, did the hand disappear? Did it stick around as a grim reminder until it was fixed to be removed? | 499 | There is no canon answer for this. Presumably the hand is still stuck on school or mortal peril. There is an argument for the hand moving to home because we know that the afterlife is a definitive thing in the Harry Potter universe (although we don't know what form it takes, we do know that it exists). However such an ... | 299 |
CMV: Limits on who can run for office are really limits on who voters are allowed to vote for. | I live in The States, but this probably applies elsewhere.
I believe it sets a poor precedent that the government is allowed to set limitations on who may be voted into office. Democracy is based on the idea that people should be allowed to choose who leads them, and restricting those choices is useless and undemocra... | 76 | The only limits in the US on who can run for office are citizenship, area of residence for local positions, and age for congress and president. (Edit: and criminal history as mentioned by another poster.)
Do you think that an elected official shouldn't have to reside in the region that he or she is representing?
Do y... | 15 |
ELI5: Why did older cartoons always have ‘xx’ on the label of something like a beer or the like? | I may be misremembering but was it just Looney Tunes cartoons or was it a blanket theme? | 34 | A blanket theme. When alcohol, like moonshine, was distilled they placed an "X" on the side of the bottle after each distillation. "XXX" is meant it was distilled three times and would have been smoother and higher in alcohol content | 79 |
[Fairly Oddparents] The fairies had all the magic in the universe, and can turn into anything. Why can't they change their color to others besides magenta and green? | 27 | They can!
In fact their most recognizable form are two gold fish who look completely normal except for the eyes.
Cosmo and Wanda probably just turn into colour coded objects for their godparents to make it easier for them to find them. | 44 | |
[Game of Thrones] Had Robb been informed of House Bolton or House Frey's treason, could he have won the war? | Assuming of course that either:
A) At Harrenhal, Brienne decides to warn the Starks of Roose's new friendship with Tywin and refusal to send Jaime back to Robb (via undetected raven)
B) Messages between Tywin and Walder Frey reassuring recompense for the Red Wedding plot are intercepted by someone loyal to the North ... | 59 | Probably not. We're told that the Stark army is running on fumes through the show and it's only Robb's (and Roose's) tactical genius that is allowing them to punch above their expected weight (and also that the North is like *really* hard to invade). Roose flips because he sees the writing on the wall and doesn't like ... | 33 |
How do almost extinct species revive without the damaging effects of inbreeding? | I've heard a few stories about how some species have been brought back to vibrancy despite the population of the species being very low, sometimes down to the double digits. If the number of remaining animals in a species decreases to these dramatically low numbers, how do scientists prevent the very small remaining ge... | 6,074 | Inbreeding makes the passing on of deleterious genes more likely, not a certainty. The subsequent generations are still under the same evolutionary pressure, where genes with a net negative result are still selected against. | 3,460 |
ELI5: Why don't video games come out when they're finished? | Fallout 4 and every other game I want makes me ask this question everytime.
-When I mean "finished" I'm referring to the content on the game copies sent to stores and what is pre-downloaded through steam or xbox live. Not day 1 patches. The stores have the copies. The marketing for Fallout 4 or Halo 5 was well comple... | 17 | It is impossible to make any software absolutely perfect. Development is a very long process and releases are timed with an estimate on when it will be done and coordinated with marketting.
Would you rather every game be delayed at the last minute because a clipboard animates like a shield? | 22 |
Knighthood. To me the UK's whole concept of "knighting" and the "Sir" title etc in today's world is simply a disgusting and ridiculous version of a modern-day popularity contest, and I really have a hard time trying to respect it at all. CMV | As you can probably guess I am American. It's (very) arguable that our forefathers had the exact same viewpoint I do, which could be one of the many reasons they wanted to be independent of Britain. I understand there is actually a passage in our constitution that forbids an American citizen from having or formally b... | 17 | Define respect. Its as respectable as Christmas; its has absurd nonsense orgins, but someone giving you a gift doesn't mean that they are a pagan who will be killing sheep because the moon is in the right place in the sky. *Cult*ure is silly but its just part of every part of society. | 13 |
ELI5: why are people upset over red starbucks cup? | 23 | It's part of a larger "War on Christmas" argument that get's brought up every year. Over the last several years, companies have done different things to make the holiday season more inclusive for everyone. The big one was getting workers to say "Happy Holidays" to customers instead of "Merry Christmas" since not ever... | 38 | |
[Batman] How does Batman feel when a police officer is forced to use deadly force? | Does he blame himself for not being there? What does he say to the cop? | 22 | Batman only holds killing against those who are powerful enough to do it as an option. A scared police officer fighting for his life is not abusing his power, his authority, or going beyond the justice system.
Superman killing a criminal is a very different thing, as he was under no threat whatsoever and the killing w... | 33 |
ELI5: Why does it feel so good to "crack" my neck? | It doesn't just feel good physically, but also makes me feel relaxed and almost like I've taken a very short lasting drug. | 429 | It's likely that you've gotten used to the feeling of air bubbles within but it feels better if they aren't present (ie. They would cause discomfort if you weren't already desensitized). That's why it feels better when you pop them ("cracking" your neck). | 78 |
Native American Philosophy | Hello, if there is one definitive text in Native American philosophy, what is it? And if no such choice exists, are there any legitimate contenders? Thank you. | 42 | I always recommend " The Stones Shall Cry Out" by George Tinker as a first step. It highlights the issue of even starting to compare Indian philosophy with "Western" philosophy rather clearly.
From there, I'd recommend reading *God is Red* and *American Indian Literary Nationalism* before moving on to actual Indian s... | 28 |
Why are free neutrons unstable? | Neutrons that are not part of a nucleus but just kind of floating around by themselves are unstable and undergo beta decay with a half life around 15 minutes. Do we know why they are unstable? What is making them decay?
What keeps them from decaying when they are in the nucleus of an atom? Why are free protons, b... | 29 | Protons are slightly less massive (and therefore, energetic) then neutrons, and a neutron can turn into a proton by beta decay. Because the higher energy neutron can turn into the lower energy proton, it eventually does.
A proton can't spontaneously decay into a neutron by inverse beta decay because the neutron has hi... | 13 |
How to get better at Asking Questions? | I am a PhD student in the computer science field. And I've just been wondering... What's a good way at getting better at asking questions? Or better at formulating them?
I've noticed one thing that really sets apart an academic is the questions and type of questions they ask during a guest lecturer or seminar.
I can... | 81 | Practice and experience. Usually, the people who sound "eloquent" are just using the precise terminology for their field, which is something that comes from spending a lot of time working in that field and becoming very familiar with it. Once you have a strong working vocabulary it becomes much easier to be more concis... | 56 |
Why is it bad for someone who has a concussion to fall asleep? | 41 | A possible complication of a concussion is a brain bleed. They keep you overnight at the hospital to make sure that this doesn't happen. It's not exactly bad for you to sleep on a concussion, but it is bad to sleep if your brain is bleeding. Because you might not wake up. | 15 | |
ELI5: What exactly happens when an animal imprints on a human? Does it understand that its new "mother" is not the same species? | 150 | For true imprinting, they won't recognize their own species later on. You'll run into this a lot of rehab facilities where human-raised wildlife imprinted as babies and then can't integrate into a flock/herd/whatever. They won't be successful at breeding or parenting. There are other animals that become socialized and ... | 33 | |
[Star Wars ROTS] Why didn't Grievous just let the hundreds of Battle Droids in the hanger all pointing their weapons at Obi Wan shoot him when he jumped down and made his big grandstanding entrance in front of him? | It would have been the logical thing to do and Obi Wan was an arsehole for thinking anything else other than that would happen. | 117 | Yeah, sure, then Obi-Wan jumps back up into the rafters while Grievous' army shreds itself (and *him*, since he was standing there too) to pieces. He knows the quality of his droids, and he does *not* trust them to fire their blasters in any direction that includes him. | 301 |
CMV: The Muppet Christmas Carol is the best Christmas movie ever made. | A shocking claim, perhaps? Here is my evidence:
-Michael Caine in one of the most auspicious performances of his career
-A song from the theatrical version called "The Love is Gone", wherein Belle breaks young Scrooge's heart as old Scrooge watches in despair
-The Great Gonzo as Charles Dickens
-Consistently amazing... | 164 | Die Hard is perhaps the greatest action movie of all time, still holds up completely 27 years later and led to a flood of imitators trying to recreate the magic of the best Christmas film of all time. | 81 |
[Fairly OddParents!] is Dino Dads meat vision technically vegan? | I mean they were made by his eyes and didn’t come from the corpse of an animal so could vegans eat it | 17 | No, whenever he uses it nearby farm animals start disappearing piece by piece. It's pretty messed up actually. The show doesn't really cover it, but they go into a lot of detail in the novels.
But actually though, scientists are working on lab-grown meat that is chemically indistinguishable from the real thing. Som... | 18 |
What’s special about hypersonic speeds? | I understand that characteristics of airflow change when it becomes super sonic (Mach 1), but what is special about specifically 5 times that speed? Is it just that just a human label or is there a physical phenomenon at Mach 5? | 2,321 | Hypersonics are conveniently defined as any speed above Mach 5, because around Mach 5 a lot of engineering problems change their form.
At supersonic speeds, you can quite easily maintain subsonic combustion (a shock cone or ramp intake will do much of this, check Concorde's intakes which are well documented) for a con... | 3,493 |
ELI5: Why does the sweat from the armpit smell worse than sweat from any other part of the body? | 23 | Armpits have **apocrine sweat glands**. These differ from sweat glands elsewhere on the body because they secrete oils in addition to sweat. The oils are then broken down for energy by bacteria on the skin, and the byproducts produce body odor. It's also thought that armpit hair helps spread the odorous chemicals into ... | 12 | |
[40K] Why are Titans walkers? | Walkers aren't the best option, because of the weak joints they have and I think they're slower than equivalent tracked vehicles. They also have slimmer profile and can be position into a hull down position (like that would help... The digging sites for Titan equivalent vehicles would be massive). | 67 | Its because they are the best option for their size, and given the availabke technology, they are both faster and can operate in more terrain than treaded vehicles.
At smaller sized tracked vehicles make more sense, but titans are massive on a different scale, and at their size, anything but lega stop making sense | 46 |
Why do people pace back and forth when they're thinking really hard about something? | I know I do this, and I start doing it without even thinking about it. Does it help you concentrate somehow? | 82 | I don't know if there is any literature on the subject out there, but one possible reason may be less about thinking and more of a physiological response to the stress or anxiety that comes along with it. We tend to use rocking or rhythmic patterns when trying to regulate. (You can look into research on stress regulati... | 19 |
[X-Men] Why is the X-gene responsible for so many wildly different powers? | 58 | I don't believe this is ever explored in a canon way, but there is a fan theory that explains this. It says that the X gene really gives everyone the same power - reality warping. Its how this reality warping *manifests* that gives them their power. Wolverine subconsciously warps reality so that he regenerates, Storm w... | 56 | |
CMV: most new genders and gender labels are not productive to have in the long run |
Right now US, and in lesser extent other western countries, cultural and social complexes are centred around “identity”. Knowing to what group you belong and what name you give to that group is very important for your personal identity. Delineations of Identity are thus very important, and things like racial categorie... | 1,118 | >Shouldnt the better course of action be to let biological sex be biological sex.
In theory yes, but in practice this kind of argument is very strongly associated with people who will then proceed to give a very broad expectation of how many spaces biological sex labels should matter in.
I mean, sure, hopefully 10... | 226 |
[Werewolves] Sometimes the moon is visible during the day. Does this effect werewolves? | During a new moon, the moon can be seen during the day as a full moon. | 384 | It depends on the series context. Werewolves traditionally only roam at full moon. The moon can only be full when it is opposite to the position of the sun comparative to the position of the Earth. Therefore, full moons can only rise after sunset, and so the werewolf only roams at night. Since the moon cannot be 100% f... | 204 |
What is the meaningful distinction between nuclides and isotopes? | I've read several different articles on this, talked to nuke engineers, and really just failed to receive a consistent and satisfactory answer. ~~It almost seems like "nuclide" is a preferred term for the nukes while "isotope" is preferred by chemists.~~ I understand very well the concept of elements, atomic masses, et... | 26 | >For instance, is it proper to refer to U-238 as an isotope of uranium, or is U-238 a nuclide?
Uranium-238 is an isotope of uranium and a nuclide.
A nuclide is just a bound (or resonant) nuclear system with a given Z and N.
"Isotopes" refer to nuclides with the same Z.
"Isotones" refer to nuclides with the same ... | 10 |
ELI5: if the earth is spinning around, while also circling the sun, while also flying through the milk way, while also jetting through the galaxy…How can we know with such precision EXACTLY where stars are/were/will be? | 5,781 | Picture an anthill in your front yard. The ants are moving around all the time, right? How far are they from the moon? Well, we'd say they're 238,855 miles from the moon. It doesn't really matter whether they're on top of the anthill or a few inches underground, because those distances are meaningless on the scale ... | 7,302 | |
[Borderlands] Am I killing the same Psychos and Marauders over and over again? | On Pandora they seem to have the ability to digistruct a new body for someone and somehow put their consciousness in it when they die. does everyone have disability or is it unique to vault hunters for some reason? When I clear out an area and then go back a few hours later and it's full of psychos and raiders again ar... | 44 | The New-U stations are, by word of God, noncanonical. Yes, this presents an issue with a certain sidequest in the latter part of BL2, and the writers admitted as much.
So no, you're not killing the same bandits and psychos over and over again. | 66 |
How do computers know how to interpret binary code/machine code? | How does the computer ‘know’ that a = 01100001? It seems like some lower language is always needed to explain the significance.
As in, 01100001 is inputted. Some language (A) presumably has to tell the computer how to interpret the binary. Then wouldn’t a second language, B, have to tell the computer how to interpret ... | 38 | The binary is interpreted as what path the electrons take in the physical hardware. There's no program that does this, they flow through the wires based on the ones and zeroes that determine which paths allow the flow to go through | 21 |
Do whales experience holding their breath the same as us? | I was watching a video on blue whales just now and found out they surface to breathe once every half hour normally and I wondered how it must feel to them to hold their breath for that long. I can hold my breath for only 30 seconds before I start to feel a little uncomfortable.
Do whales have the same system as us th... | 20 | No, whales experience holding their breath differently than us. Whales have a different breathing system than humans that allows them to remain underwater for extended periods of time. Whales have evolved a set of physiological adaptations that enable them to hold their breath for long periods of time without feeling t... | 12 |
ELI5: What do steak grades mean? | For e.g MB3+, what does this mean when referring to a steak? | 37 | From USDA website on beef grades:
* Prime Grade is produced from young, well-fed beef cattle. It has abundant marbling and is generally sold in restaurants and hotels. Prime roasts and steaks are excellent for dry-heat cooking (broiling, roasting, or grilling).
* Choice Grade is high quality, but has less marbling th... | 47 |
"Every polynomial of degree n has exactly n roots" | We learned this in class the other day, but what about say f(X)=x²?, There is only one root, but shouldn't there be two according to the prior statement? | 34 | The statement is really more like 'every polynomial of degree n can be factored into the form a(x-c1)(x-c2)...(x-cn)' for constants a,c1,...,cn.' The ci don't have to be distinct.
For convenience, we say that c1,...,cn are the n roots *counted with multiplicity*. That is, in the case if x^(2), it can be said to have t... | 54 |
ELI5: Why can cows and sheep crap in fields where they eat without getting sick, while faecal matter lying about quickly leads to diseases like cholera in humans? | 794 | Cattle have a natural aversion to feeding around their own dung. This can lead to the formation of taller ungrazed patches of heavily fertilized sward. These habitat patches, termed "islets", can be beneficial for many grassland arthropods, including spiders (Araneae) and bugs (Hemiptera). They have an important functi... | 628 | |
[Dark Souls] Assuming the PC embraces the Dark ending and brings about the age of Dark, is there a reverse apocalyptic scenario when the age of fire inevitably emerges? | 33 | Exactly that. If the Chosen Undead were to link the fire, it would eventually begin to fade again. Unless powerful souls are reclaimed and used to fuel the First Flame, it will burn so low that an age of Dark begins.
Similarly, if the Chosen Undead chooses to *not* link the fire, they withhold those powerful souls an... | 26 | |
What is the biochemical origin of caffeine dependence? | There's a joke that if you've been drinking coffee for a long time, when you wake up you'll need a coffee to get you back to the point where you were before you started regularly drinking coffee. But, if you stop for a week or two, your baseline goes back up. What happens to regular coffee drinkers to lower their basel... | 4,542 | Caffeine is a nonselective adenosine receptor antagonist, acting at A1, A2a, A2b, and A3 receptors (it also binds to a few other receptors, but we’ll ignore those for simplicity’s sake). From knockout studies in mice, it appears A2a is critical for the stimulating effect of caffeine. In the brain, Adenosine levels fluc... | 3,039 |
Has anyone had major revisions requested after fixing minor? | I submitted a paper several months ago and recieved a response of "Based on the advice received, I have decided that your manuscript can be accepted for publication after you have carried out the corrections as suggested by the reviewer(s)." The minor revisions were to simply fix a graph and the formatting of my refere... | 15 | This can happen, either because when you made the minor changes, the reviewer (sometimes because of the minor changes, sometimes just because they had a changed point of view) saw a flaw they've not seen before. More scrutiny = more chance of weaknesses to be seen. Maybe they weren't thorough the first time around, or ... | 42 |
[Hitchhiker's Guide] In Mostly Harmless why is the Earth still destroyed even though the dolphin's had a new one built? | In addition, why is there a random planet at the same coordinates as Earth and why is Ford's section on Earth in the Guide still say, "Mostly Harmless" | 17 | The earth sits on a multiverse nexus destroying it just gives you access to an alternate version.
This was inconvenient to the Vogons who wanted a motorway there so they created the second version of the guide to ensure Earths destruction.
The guide manipulates others into destroying the Earth every time -includin... | 22 |
I believe that punishment should be based on the action taken alone, and the consequences should have absolutely no bearing on it. CMV. | First and foremost, my apologies if this is a repost- it seems like a somewhat obvious CMV candidate. I could find no post like it though, so please delete this and redirect me if this view has been expressed before.
It is hard to significantly expand on the view as presented in the title; I believe simply that, in ac... | 16 | This idea gets a little bit messy in practice, because luck and circumstances play a role in virtually all actions. In your drunk driving example, how would you punish someone who *intends* to drive drunk but passes out before they start the car? Or what about someone who *intends* to drive drunk, but then is offered a... | 15 |
Has anyone had their PhD thesis defense rejected? | Hello reddit, I've been reading up on people's PhD defenses recently and I've been wondering - has anyone actually had their PhD thesis rejected? Is the defense more of a conversation/formality than a "final exam"? Can one redo their defense?
Hope this isn't an ignorant question, I am just curious. Seems as if you ... | 28 | As has already been said, a good advisor won't allow you to schedule the defense if he or she doesn't believe you're pretty likely to pass.
However, if you've been in the program and you're almost out of time (most programs say if you don't have PhD in hand in X years, you're thrown out) then occasionally you'll be a... | 20 |
ELI5: Why are some frogs, etc., poisonous? Unless the poison is so lethal that any predators die on contact, the frog still gets eaten. How does this help survival? | 27 | It’s not just poison, the bright coloration, instead of camouflage, alerts predators to the poison, and predators who survive then learn that those tiny frogs with bright blue markings are not safe to eat, and so poison dart frogs go uneaten, save those unlucky martyrs of frogkind.
Incidentally, poison dart frogs aren... | 39 | |
ELI5: why does plastic turn white when bent? | 287 | I can answer this!!
So plastic is made up of microscopic spaghetti (it's actually made up of long chains of some form of carbon molecule, but we will pretend it's spaghetti). There are two main types of plastic; plastic where the spaghetti is completely random and all over the place, and plastic where the spaghetti is... | 205 | |
[Werewolves] Would a werewolf die if they ate chocolate? | 21 | Probably not. Dogs and wolves' stomachs can't process it, but werewolves still have physical characteristics of humans, which are omnivorous.
There was a show that pointed out werewolves take painful s***s after a full moon, with human bones and whatnot coming out. | 30 | |
I believe that free speech should not apply to all forms os speech, example, religious hate speech. CMV | Free speech as always given us a means of change, a trustworthy way of fighting real issues, sometimes even a way of uncovering corruption and crimes all over the world.
* I am Portuguese, living in Portugal. Free speech here is not an issue. However, in Europe there is a growing number of "religious leaders" from all... | 21 | Once the majority is able to silence the opinions of a minority, where does one stop? Now that you have the ability to stop religious hate speech, why not get rid of the next thing that offends the majority of people or "causes problems". Of course, this could lead to lots of policy that is detrimental to society in th... | 31 |
[DC] Can the Yellow ring/lantern be used as a force of good? E.g. fear of losing your loved ones so you fight and be empowered by it | Or does this translate to a Darth Vader-esque route? | 661 | It's more or less goes full Dark Side. Sinestro himself was motivated by a desire to accomplish what he believed was the Green Lantern Corps' actual directive, bring peace, when he felt they weren't capable. Except "bring peace" rapidly became "impose order" which gave way to "accumulate power" towards the end. He w... | 502 |
CMV: The concept of "doing your own research" is prone to bad understanding when you are a non-expert | This is NOT an argument on doing any research at all, I highly recommend people seek to learn things.
Rather I am pointing out there is a very large potential for bad science when laymen tries to do research.
I don't mean just youtube videos. I mean when a layman reads actual research they often make poor assum... | 836 | Are we assuming an "expert" Is void of subjective bias? Even Science bases research on agreed upon Theory.
Self discovery is based on individual observations, and as a Social Science researcher, I'd recommend researching to understand, not to prove a point.
"The truth is rarely pure, and never simple"! | 105 |
ELI5: Would a vacuum cleaner work in space? | 15 | Despite their name, vacuum cleaners do not create a vacuum. They create a pressure difference by pumping air out through the filter chamber. But since there would be no air in open space they won't create a pressure difference. | 19 | |
Why is/was there a tendency for like minerals to collect together on earth? | It seems that the original source for minerals was random and that they should be randomly, and relatively homogeneously spread over the surface of the earth. Yet minerals like iron oxide, sodium chloride, gold, silver, (and most others it seems) have had a significant tendency to be found concentrated in various area... | 306 | 2 parts to this (admittedly insufficient) answer.
Sodium chloride stands out on this list. Sodium chloride build up is often due to sea water being trapped or secluded from fresh water. Over time the water will evaporate leaving the salt concentrated in that area.
As for concentration of other elements, despite start... | 71 |
[Batman] What plot would Calendar Man have for April Fool's and Easter being on the same day? | The thought came to me when I remembered the date-specific Calendar Man easter egg in Arkham City. | 129 | Poison chocolate easter eggs, annouce it at midnight so batman has 6hours to contain the eggs and come midday for Calendar to tell him it was a hoax and that batman being smarter. Should of figured that out before upsetting all the kids by taken there chocolate eggs away | 109 |
Standing on a rock at the absolute edge of the Milky Way, facing away from the galaxy. What do I see above me? | *For the naked eye.*
Is the sky filled with stars? Do I only see light from the local cluster, or is it mostly pitch black?
Also, if you have any material on this I’d love a link. | 155 | It would be mostly pitch black.
There is no absolute edge of the Milky Way - there's just fewer and fewer stars as you go further out. So once you're far enough out that there's no stars close enough to be visible as individual stars "in front" of you, you're in a region that's so lacking in stars that there's there's... | 225 |
CMV: TV Shows Are HANDS DOWN Way Better Than Movies. | Movies are dope but I think tv shows are so much better for a couple of reasons. Firstly TV shows have the time to build your love for a character, like Sons Of Anarchy for example. Their are 7 seasons in that show and the way they introduce the characters and make the characters feel like a part of your family is AMAZ... | 28 | The distinction we should make is not show vs not show. It's serialized content vs non-serialized content.
You are right that some content is definitely better to convey over a serialized show format. But not all ideas/themes/content are. Not in every case is a show a better format than a movie.
You might really en... | 25 |
[40k lore] So, how does a planetary militia deal with the overpowered forces of Chaos? | For that matter, what sort of equipment does your local Imperial militia carry, and how does it deal with obscenely nightmarish forces such as Plague/Noise/Rubric Marines, rotting virus demons, etc.
It seems that every time chaos is brought up, there's no chance unless pitted against Ultramarines or titans. I'm persis... | 21 | The Imperium is vast, with uncounted worlds. The attacks of Chaos are beyond number, as well. But fortunately for humanity, not all those attacks are Black Crusades. Let me elaborate.
Chaos attacks can first be divided into two categories: attacks from within and attacks from without.
The examples you mentioned al... | 17 |
ELI5: Why, when on a low calorie diet, does your body consume muscle as well as fat? Why not just fat? | 46 | Extra muscle is a luxury. Your body wants to be strong, but the more muscle it has, the more food it requires. If it thinks there isn't enough food available, it reduces the amount of muscle you have so you will use less in the long run. | 16 | |
[avatar] why was the avatar, the only one who could defeat the fire lord? | throughout the series, it was said that only the avatar could defeat the fire lord, but why? what is so special about the avatar that he was the only one who could do that? what would have happened if someone else had done this? | 52 | The Avatar was probably the only person powerful enough to take the Fire Lord in single combat. And of the others that *may* have been able to do it... none were likely to end the war by doing so.
The Avatar, however, stands apart from the nations of the world, and keeps peace between them.
Add to that, the Avatar ... | 83 |
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