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(Marvel) What were scientists looking for when they found Captain America's body?

We've all heard he is a man out of time, frozen for many years. What was it the scientists were looking for when they found the body of Captain America?

In the MCU the scientists were most like looking for lost Hydra technology after WWII after discovering a weird signal coming from that location. Shield has been known to be researching Hydra tech before the New York Invasion and was most likely following some leads. Finding Captain America was a byproduct of looking for technology.

Why is it that humans can regenerate skin, bone and muscle after an injury but can't regrow lost limbs or eyes?

It's not clear to me how the body "knows" what the difference between healing a cut in your leg or burn on your hand and the loss of a hand or ear, etc. Obviously the severity of the wound is more severe in the latter case but isn't the process the same (regrowing cells that match the cells around the wound based on the person's DNA)? As a follow up would it be possible with stem cells to grant the body the ability to regrow any lost body part or would the body part still need to be artificially grown in a lab and then grafted onto the body?

The regeneration process for each tissue type in our body is very different. Some types of tissues are able to regrow very fast either because the cells they are composed of are proliferative, or because they have adult stem cell pools associated with the tissue. Skin is an example of a tissue that is composed of highly proliferative cells (fibroblasts and epithelial cells). Muscle has an associated stem cell population called satellite cells that are activated during muscle regeneration and differentiate into (that is, change irreversibly into) muscle fibers, while also maintaining their own population. Bone is somewhat special among tissue types in that it is composed primarily of a hard, calcium-based extracellular matrix that is secreted by cells called osteoblasts rather than of the cells themselves, so when bone is injured, osteoblasts secrete more matrix to heal the bone. The adult stem cell precursors of osteoblasts (and several other cell types), bone marrow mesenchymal stem cells, are also found in significant numbers in adults. There is an obvious evolutionary advantage to these tissue types' ability to heal quickly: skin, as our outer layer of defense against the pathogens of the outside world, needs to be able to cover any abrasions quickly, while muscle and bone accumulate damage as they are used (especially muscle - damage and subsequent repair is the mechanism by which muscle grows after exercise). Other cell types, such as nerve cells or pancreatic islet cells, are post-mitotic, which means they no longer proliferate under normal conditions. This means that if these cells die, new cells are not formed. Also, the structures you mentioned, limbs and eyes, are very complicated structures composed of more than one tissue type arranged in specific geometrical relationships with one another. Regenerating an entire structure like this requires coordinated action between different cell types. Studying the mechanisms by which these complicated structures are formed during embryonic development, and hopefully discovering ways to apply them to adults using stem cell therapies (either embryonic stem cell therapies or stem cell therapies leveraging the populations of adult stem cells that are present in our bodies), are active areas of research central to a discipline of biomedical research called regenerative medicine. Source: Bioengineering student at UC Berkeley, with a focus on cell and tissue engineering. Working in a stem cell lab.

ELI5: Why doesn't Tumblr receive child pornography charges even though it's full of nudes of minors?

As many of you know, tumblr's main demographic is underaged teenage girls. A large portion of their contributions are selfies and nudes. There's many different tags for this, notoriously topless tuesday. With all the jailbait drama that's been going around, surely tumblr would be noticed?

These sites can't police every single post. If one is brought to their attention they deal with it, but sites like Facebook and Tumblr get literally thousands of posts a minute. Users are generally responsible for the content they post, not the hosting site as long as they've got policies in place to handle inappropriate posts. If you're a 16 year old girl posting nudes to your Tumblr feed you're more likely to get in trouble for than they are.

[Mad Max 2] Would Lord Humongous have let the people in the compound go?

He gives a pretty impassioned speech about letting them go when he realistically could have said nothing and stormed/layed siege to the base. Also, whilst they are clearly the aggressors in the siutation, they are not the first ones to draw blood (granted it's a kid that does that)

It’s a bad idea to engage in battle with an opponent who can fight back when you’re living in anarchy and have no medical system. The Humungus wanted the refinery, not a fight where his gang could get depleted.

ELI5: How come a business will position itself near another business/businesses that offer the same service?

Why will there be all different kinds of places(ie: fast food places, lowes and home depot, etc) on the same road/in the same area if they are all competitors? What drives the decisions to put a business near another business/multiple businesses that provide the same service? Also, if this is so common, how come you never see 'duplicate' businesses within strip malls?

Imagine a beach with 2 drink stands, one in the middle of the left half of the beach and 1 in the middle of the right half. That would be optimal. Lets say the drink stand from the right half moves to the middle of the whole beach. Now he gets all the customers of the right half and some from the left. Consequently the left drink stand is now forced to also move to the middle if he doesnt want to lose out on business

[The Hobbit: Desolation of Smaug] In the movie, Bilbo almost tells Gandalf he has the ring right before they enter Mirkwood. What would have happened if he had told him?

In all likelihood, nothing. Gandalf knew Bilbo had some kind of magical ring for many years before he discovered it was actually the One Ring. In fact, Gandalf was probably *more* suspicious of the ring's potential influence because Bilbo would never have ordinarily tried to conceal its existence or lie about how he acquired it.

[Bollywood] What is the name of the superpower all these Indian men have, and what are it's limits?

Examples: https://np.reddit.com/r/BollywoodRealism/top/

Any square-jawed male with solid morals can do that. It's very similar to how action movie heroes only take grazes from automatic weapon fire, and when they do take a bullet they can survive and keep fighting with minimal first aid.

ELI5: why do you always feel better after a shower when you're sick?

Is there something actually happening or just a placebo?

More than likely your body is dehydrated from trying to make you not sick, and a shower helps rehydrate you, if only a little bit. Plus, if your ailment has something to do with your sinuses, the hot steam of the shower will help alleviate some of the build up in there.

[Star Wars] Why did Sidious go from a caring father-figure to some distant "master" figure to Vader?

I mean, after he wore the hood and everything, their relationship didn't seem as close as Anakin-Palpatine. I get that Sidious just revealed himself as a Sith lord, but he and Vader could've still had a good relationship right? It seems all that happens between them now is Vader gets on his knees and becomes Sidous' bitch everytime a holo appears. Couldn't Vader be carefree around him? Equal footing at least?

Well, one thing to keep in mind is that Palpatine completely coaxed Anakin out of his shell only to manipulate the young jedi's vulnerability and fear (which the Jedi's could not help him quell). Right here we see that Sidious does not care about the person the is Anakin, but the tool that is Vader. there is no true relationship. Additionally, Vader is subordinate to Sidious per rule of two. They are not meant to be "allies", but adversaries to ensure the strength of the Sith. Lastly, the light within Anakin was severely dimmed when he became Vader. He had slain children, his master had "betrayed" him, and the love of his life, whom he would betray the Order for, had died.

[DBZ] Why doesn't anyone ever start a battle with their most powerful ki-based attack?

Every battle I've seen, every fighter (with the only exception maybe being Kid Buu) starts the battle off with a series of punches and kicks against their opponent who they clearly know won't be down for the count. This makes sense for villains who like to toy with their opponents, but for Goku & Co, they're DEFENDING the earth against people who want to destroy it and instead of just busting out the big guns early, every fight they have seems to be a war of attrition. tldr; Why doesn't Goku start off every battle against an villain by powering up to full strength and launching his most powerful Kamehameha?

There are a couple big things at play here: 1. Even when defending the Earth, Goku usually doesn't start the fight seriously. It's usually implied that Goku spends at least a portion of the battle holding back and testing his opponent to get an idea of their capabilities before seriously attacking. Other fighters tend to do something similar. This has both personal enjoyment reasons (most of the fighters enjoy actually fighting, particularly Goku who is a fighter first, and a hero second) and serious reasons. At the start of the battle each fighter is trying to determine just how powerful and what capabilities their opponent has. Both fighters usually begin the battle in a suppressed power state masking their full capacity. Without knowing what their opponent can do they might waste power, particularly relevant versus weaker foes who are being fought prior to a major enemy, but also versus a major enemy who might be capable of dodging an opening finisher. 2. Opening with a game ending Ki blast is risky. Powerful attacks often have a period of charging which telegraphs the technique, and this is further exacerbated by the fact that even attacks with little to no chargeup time can be avoided. Further, full powered Ki blasts, unlike punches and kicks, seem to use up considerable amounts of endurance. It's usually after using one of these finishing techniques that characters tend to state that they've lost a substantial amount of energy. Not going all in before you've put your opponent in a position where they have to take/oppose the attack insures you don't spend your energy pointlessly. Also if you miss, if you're a good guy at least, you have to make sure your ultimate attack isn't going to hit the planet.

[Star Wars] Why does the the republic/empire change the look of there troops/ships/fighters so often? When other factions rarely (or never) did, like rebels and the trade federation.

Seems like they are always changing up troop armor and star ships. Changing out millions (billions?) of troop armor and thousands of star ships can't be cheap. Does the republic/empire lease and not buy?

Evolving requirements. The initial launch of clonetroopers came from and were at least in part trained by -- or had their training regimens shaped by -- Jango Fett. Their armor bears many similarities to his own armor, no doubt due in part to the nature of what he was accustomed and trained to do. Fast-forward over the course of the Clone War and the initial launch of the clones has now had time to identify field-tested flaws in the original armor design. In order to ensure maximum effectiveness of its troops, the Republic continually refines the armor to account for these deficiencies and also to build-in new features that troops may find useful as the war progresses. During the Imperial transition period, purpose-grown and designed clonetroopers saw decreasing use in favor of somewhat more conventionally sourced and trained stormtroopers. The Clone War was over; the stormtroopers' purpose wasn't fighting a massive symmetric war, but rather peacekeeping and asymmetric warfare against guerrilla resistance forces. This calls for different equipment, too. War armor doesn't provide what stormtroopers generally need. And, to be clear, what we see in documentary footage is fairly *atypical* of the usual stormtrooper assignments; the Rebellion was *tiny* in comparison to the breadth of security responsibilities the Empire faced. The same is largely true for ships. A space superiority fighter you purpose-build to fight droid fighters just doesn't have the same requirements as an all-around, quick-deployment, high-mobility fighter. That exact same purpose mismatch travels all the way up the chain to the star dreadnought super ships like *Executor*.

ELI5: Why do stars, including the sun, shine? What makes the light?

The light comes from the upper layers of the sun. They shine because they're hot, just like lightbulbs and toasters do. The sun is so bright because at 5500 °C/ 9900 F, the effect is pretty big, and the sun's photosphere is more than 100 kilometers thick, all of which is shining. That adds up. You may hear people say stuff about photons from nuclear fusion in the core. ~~Don't believe them.~~ Read their comments with polite skepticism. That is not the light that reaches your eyes. Underneath the photosphere, the gas doesn't really let any light through. If you are interested in where stars get their energy from, you should read those comments, though. *Edit: phrasing*

ELI5: Does holding a shirt or cloth up to your face during a fire actually keep you from breathing in smoke? If so, how does that work?

It works to a degree, because the cloth filters out some of the particulate matter - that's all smoke is at the end of the day - airborne particles as a byproduct of combustion. BUT, there is a diminishing return with them - same reason dust masks are disposable and shouldn't be reused. A filter will block some of what you're breathing in, but over time they get clogged with crap, so it actually concentrates what you're trying to avoid. Ditto with things like water filters - at first they filter out the shit you don't want in your water, but after a while they've got that much shit in them that they make the water quality worse.

What actually is happening when you fold paper? What makes it go from bending to creasing at a certain point?

The same can apply to other materials, but I fold paper all day at work. Which reminds me, I should get back to work.

A lot of materials have a yield stress. Including paper. When enough force is applied, the stress in the paper can exceed its yield stress. From that point on the material is plasticly deformed, which means when you stop applying force, the paper will not bend back into its original shape.

[Marvel] Why doesn't Xavier walk?

Watching *Wolverine and the X-Men*, where Prof X is sent to the future somehow and constructs himself a pair of bionic leg braces that help him walk. Why has Forge never made the Prof some working leg braces?

Part of life is accepting who you are. This goes double for the professor who regularly is seen in public arenas and by prospective students and their parents. It would not do well to be seen as Robot Xavier. He could switch back and forth between the chair and robotic appendages, but he's found contentment with his current situation, and he even draws some reflective thoughts on how he came to be in his current situation by allowing it to be a reminder and perhaps even penance for past choices.

ELI5: How are lumens and candela related and what each represents.

In trying to learn more about each, I was curious if my analogy was appropriate. Is candela sort of like a decibel? In the sense that you can double the lumens, but that doesn't double the intensity of the light. Like four hands clapping isn't twice as loud as two hands clapping.

A lumen is the total amount of light coming from a source; its "luminous power." It's equivalent to Watts, the measure of power, but weighted for human vision, e.g., an infra red lamp could put out 100 Watts but, if we can't see it it would be producing zero lumens. It's a similar idea to the special A-weighted decibel scale ("dBA") for sound that only considers sound pitches that people can hear. A candela is based on lumens but takes into account how focused the light is. A plain 1000 lumen light bulb will spread its light evenly in every direction giving about 80 candelas of "luminous intensity" (you divide by 4×π because that's the surface area of a unit sphere). Or you could have a 1000 lumen flash-light that sends almost all its light in one direction, giving off 1000 or even 10000 candela, but only directly in front. The extreme example is a focused laser beam which can have very high candela ratings with very low lumens.

[DC Comics] Does Superman become weaker at night?

Theoretically over time and if the night lasts forever yes. But keep in mind that he has been absorbing sunlight for decades so he has more than enough power inside him to last an entire night fighting.

[X-Men] With their healing factors, how strong could Wolverine or Deadpool get by constantly working out?

The way strength is built in the gym is by stressing muscles, and after micro tears in the heal, you get stronger. But the process takes time. People who use steroids can speed up this time, allowing them to work out longer and more intensely. With their healing factor, Wolverine and Deadpool could basically work out continuously, increasing their strength, with the only limiting factor being calories to fuel the work and healing. How strong could someone with a healing factor get from constant working out? What is the upper limit of human strength when you can recover nearly immediately from any workout?

This is actually a major reason for both Wolverine's strength and athleticism, since the adamantium coating his skeleton happens to add just over a hundred pounds onto his frame; he'd weigh 195 without it. Because he's hauling that extra weight, his body is constantly healing his muscles to make him strong enough to compensate; he can lift 800lbs with effort, but is also stunting his growth and height.

I don't think piracy is bad. CMV

I "know a guy" who pirates plenty of software, and I don't think it is bad to do so because: 1. He would not buy the software regardless, but he is able to use it through piracy. If there was no way to pirate the software (let's use Photoshop as an example here), then he would either not use it or find a free alternative (GIMP), but he would not buy the software (especially with Photoshop, which is hundreds of dollars). 2. He is not actually taking resources or materials from a company. Most of the time, he is downloading a trial from the real developer, and then extending the trial period to never ending (with a keygen or crack). It is not like taking a toy, where the company is actually *losing* money, which would be the metal, plastic, batteries, etc. 3. Because of the two reasons above, he can actually help the company. If no matter what, he would purchase Photoshop, but he pirates it and tells me, "hey, Photoshop is great. Look, I made it look like I'm banging this hot chick!" And I say, "That's awesome, bro! I'm going to check out Photoshop!" Then I download it, use my trial, and then end up buying it. My friend just *gave* Adobe another purchase. Now please, try to CMV!

Because he isn't taking something tangible doesn't mean he isn't taking something that belongs to someone else. Intellectual property has value, and it has an ownership, and that owner should have the full to do with it what they want. Is it ok the NSA takes people's information? They're not taking anything physical from them, so they're not really losing anything by them operating. Maybe sometimes they do tap in through backdoors in software that we were trying to keep private(keygens), but c'mon, we have so much public information on social media(free alternatives) that they would get our information regardless. But hey, they can actually help. They can just let other government agents(friends) know if anything is interesting about this person(product). Intellectual property, even though it cannot be felt with the hands, has a value, and a value people hold closely and deeply. Taking other people's stuff, REGARDLESS of what happens to them, is STILL taking other people's stuff!

[Star Wars] Why doesn't the rebellion use more captured Imperial Equipment?

Servicing captured equipment is annoying at best and impossible at worst. Part of the Germans' logistical problems in World War 2 was that their trucks were scavenged and stolen from so many places that nothing was interoperable and they lacked the ability to source spare parts for many vehicles. This led to absurd attrition rates. That was with the equipment of the 1940s. Star Wars takes place in a fantastical space opera setting, where the complexity of the technology being used is impossibly far ahead of even what we have now. Using captured equipment for anything other than one-time, specific uses is just not feasible.

Does having repetitive hypoglycemia result in permanent brain damage (reduced memory and intelligence)?

[WebMD](https://www.webmd.com/diabetes/story/the-invisible-damage-diabetes-does-to-your-body) states: > Studies tie diabetes to proteins in your brain that are linked to dementia. Because of narrowed, hardened arteries, your chances of stroke are also higher. Your brain needs sugar to do its job. Repeated bouts of low blood sugar can damage the brain. I was not able to find anything else regarding this online.

Depends on how hypoglycemic you were and for how long. Severe hypoglycemia causes the same type of brain injury that hypoxia does. Brain cells need oxygen and glucose to function take away one or the other it’s the same result. Even a single hypoglycemic episode can cause severe brain damage (or death). Having repeated episodes can be similar to having multiple small strokes where you have actual death of brain cells.

Is there clay anywhere else in the solar system?

Curiosity found clay minerals on Mars a few years back. We've gone back and forth about whether they could have formed without water, though other evidence for water on Mars does point to it once being a much wetter planet, probably with a global ocean early on its history.

[LOTR/Hobbit] How long does it take for an elf to mature?

With such long life spans are they children for longer periods of time or another maturation process completely different from ours?

Mentally, elves actually develop more quickly than humans; for example, elves learn to walk and speak before they're a year old. Physically, they age at the same rate as humans until around the age of 3, after which their growth slows greatly. Elves only finish growing between the ages of 50 and 100.

ELI5: How does a clone differ from an identical twin?

Genetically, they don't. In practice, a twin is a birth defect that causes one fertilized egg to grow into two people, and a clone would be a person grown from an already-born person's DNA, probably not taken from their reproductive organs.

[Die Hard] If Al Powell the cop is on desk duty, why is he out on patrol with a police car?

He states he couldn't raise his weapon again after accidentally shooting a kid and thus put on desk duty. What was he doing with a police car when buying snacks at the convenience store and why did dispatch send him to investigate Nakatomi Plaza if he wasn't a street cop?

He’s still a cop, and a sergeant, so keep that in mind up top. “Desk duty” could mean any number of things, and as a sergeant, Al’s scope of responsibilities could entail stuff that is mostly desk-adjacent, sure. But he’s still a cop with a radio that has to leave the station sometimes. In most major American cities like Los Angeles, a police sergeant has something akin to operational authority to make judgement calls on the scene. So the fact that he gets the call and is giving orders before deputy police chief Duane Robinson arrived is no oversight. So Al could have just been on the way home (from, say, desk duty in the robbery unit) and dispatch saw him in a squad car nearby. Being a sergeant, he’s the ideal option for checking out a suspicious though serious hostage and gunfire call, and making the determination on-site if more backup is needed. That’s a no-brainer for dispatch. And remember, he said himself he was just on his way home when the call came in, so he wasn’t on patrol, really. Just the right guy at the right spot at the right time (like “Roy”)

[Dragon Ball] Cell can sense ki. Why doesn't he ever try to reach the Lookout?

Cell has shown the ability to sense ki multiple times (most notably to track down 17 and 18 when Piccolo is fighting 17), yet he never uses this to reach Kami's place. He expresses to Trunks after Grade 3 Trunks loses to Cell that he's curious as to how Trunks and Vegeta got so much stronger in a short period of time. He definitely would have felt Goku testing his power to Karin after just coming out of the Room Of Spirit And Time, so why does he just ignore the Lookout? The moment Buu could sense ki, he flies straight there. The only real reason I can think of is the moment Cell arrives in the original timeline, he is preoccupied completely with absorbing 17 and 18. Once he does so, he constructs the Cell Games to test his strength, and even encourages the Saiyans to train again for ten days. But I would think he would be at least a little bit curious as to how they get so strong so quickly, and he definitely has the means to find out.

Given that Cell is an amalgamation of the Z fighters DNA, he's inherited a lot of their strengths, but also weaknesses. His major fatal flaw was his pride/confidence in his own superiority (Thanks Vegeta). Despite his minor curiosity, he just didn't care enough to really look into it. In his mind, he's the perfect being and no one could EVER stand a chance against him. So why would he go through the trouble of sneaking a peak at their training? Plus, he had other Cell things to do, like flexing and stuff, probably.

[DC comics] How is superman the last descendant of Rao and the reason of him being the strongest Kryptonian is because of this when Kara his cousin should also have the same demigod blood and be a descendant?

Kal-El is not the last descendant of Rao - he may however be the last **pure-blood** descendant, whatever that means in Kryptonian culture. If it's anything like Egyptian pure-blood descendants of Ra, Kara probably doesn't qualify due to her mother not being a close enough relative of the house of El - IOW she's insufficiently inbred.

ELI5: Why isn't obesity considered an eating disorder?

In some cases it's considered a SYMPTOM of an eating disorder, but remember, not all obesity is caused by over eating. even if ALL obesity were caused by overeating, obesity itself would still not be an eating disorder. it would be a symptom of an eating disorder.

ELI5: Why people say "pardon my French" right before/after they swear

In the early 19th century, intellectuals and those well-traveled would often drop French words into the conversation to show how clever they were. They would then point out that the word they had just used was French, often to embarrass someone nearby who was less fluent in the language. To counter this, the less well-traveled (often poorer) people would, after swearing, loudly proclaim, towards those that had previously used French in the conversation, "Pardon *my* French." The latter stuck.

ELI5: Why do so many people use "Jesus Christ" and other God-based words as curse words and not names of evil people like Hitler in the same way?

Profanity comes from the assumption that something upheld is being debased. Curse words can come from a few places, but using words with deep seated cultural connotations force you to see it as vulgar when used in certain situations. This is because it crosses a boundary, it's taboo, it shows disrespect and people find disrespect insulting. Hitler wouldn't have the same effect because we are not "bringing it down" when using it as an exclamation.

CMV: I don't see what's wrong with suicide

A lot of my friends have been dealing with suicidal thoughts recently. If they come to me for advice, I really struggle on how to tell them/encourage them to keep living. I've been in their position but I really don't understand why people are so against suicide. If they don't like their life then why should we try to keep them here? Sometimes I just feel like telling them, "I'll miss you but it's your choice" instead of discouraging it. If they went through with it, I would genuinely applaud them for being so brave to do so. I know already know the argument "But what about the suffering the families and friends will have to deal with" But if the person genuinely wants out, then why is it so socially wrong to just let them do what they want, as sad as it is? :/ I know there's probably something wrong and twisted with the way I think because I don't know anyone with the same opinion as me so please help me to change my view Edit:: thanks guys for all the discussions I was barely expecting 5 replies so yeah it’s been interesting and insightful to hear opinions from other people. I definitely know now to be more empathetic towards people around me

A person who truly wants to die will just do it. They won't threaten to do it or tell a bunch of people. They'll just get it done. Saying that you want to die is a cry for help. If they are telling you it's very likely that they want you to try to help them change their mind. Even if they don't realize that's what's happening.

How much closer would a human have to travel (Mi./Km) towards the Sun to feel a noticeable rise in temperature? Vice verse for traveling away from the sun?

Are we in space or on earth? The sun transmits heat via radiation (vs convection or conduction). The amount of energy transmitted follows an inverse square law (1/x^2) so if you are twice as close to the sun, you experience 4 times the energy transfer. You have a LOT of variables to consider if you are in space. What is the suit made out of? does it reflect heat back? how does it conduct heat to your body? The amount of energy transferred also depends on the difference in temperature of the two bodies. In short, you need to define a lot more variables before you can get a viable answer. What is considered to be a "noticeable change", what sort of vehicle are you in? what is the vehicle made of?

[The Lion King] Mufasa is badly injured in the wildebeest stampede, but manages to survive. How does the rest of the movie play out differently?

Pretty quickly IMO. It's his word against Scar's, who was never popular to begin with, and only had an alliance with the hyenas on the promise they'd have prime access to food when he's king. Mufasa has the whole of the pride on his side. Knowing Mufasa, he probably wouldn't have Scar killed even after a murder attempt, but would have him exiled. Mufasa's injuries would probably last his entire life, and he would be more dependent on the pride to do anything physical for him until Simba came of age. Simba would grow up to be suspicious, colder, practical (think Stannis Baratheon).

How populated was the earth with Dinosaurs during the Triassic, Jurassic, Cretaceous periods?

If I were to DeLorean back to the age of the Dinosaurs, what would my chances of seeing a small/medium/large dinosaur in any encounter? Would driving anywhere be like a safari in Africa or would you really have to seek out the creatures? How different was the Triassic, Jurassic, and Cretaceous periods?

Well the Triassic was immediately following the Great Dying, 90% of life was gone, so you wouldn’t see much of anything at first. Then you’d see more Lystrasauros (sp?) which weren’t dinosaurs but rather some of the last of the Mammal like Reptiles. They were really the first animals to recover and were everywhere. Then you start seeing a rising group of reptiles, the archosaurs, the precursors to crocodiles on the one hand, and dinosaurs on the other. After that the first small dinosaurs start appearing, as do mammals. At the end of the Triassic there’s another extinction event that kills off the rest of the mammal like reptiles and the large archosaurs, but the dinosaurs thrive and dominate. In the Jurassic and Cretaceous they’re ubiquitous.

ELI5: What happens when a magnet is too close to a hard drive and ruins it? Does this also apply to solid state drives?

Title pretty much says it all.

A magnetic field is like waves hitting the beach. A normal hard drive is like drawing your data into the sand. The data is washed away by the waves, because they move the sand. A solid state drive is like drawing your data with little stones. They aren't moved by the waves, so they wont be affected by the waves.

What happens inside the digestive system when a lactose intolerant person consumes dairy?

Your gut just lacks the enzymes to process the lactose, the bacteria that then meet the undigested lactose produce a bunch of nasty byproducts as they make efforts to devour the sugar. They produce lots of gas and the bacteria for the most part can't really handle it so the material just kinda gets shoved along the digestive tract as your bowels become filled with gas(at a rapid rate), causing diarrhea

ELI5: Why are some types of alcohol drinkable while some, like rubbing alcohol will kill you?

"Alcohol" is a general term for a group of organic substances. There are a lot of them and almost all alcohols are poison for the human body. However, at some point in time people found out that beer tastes well, and over the course of many generations a pretty good resistance to a single alcohol that is called ethanol was developed (hurray to the liver). So only one Alcohol is somewhat safe for consumption **in very small quantities**, which has its reason in ancient human culture, all the other ones really are not (a few ml of methanol will blind you, a few more will kill you, for starters).

ELI5: Considering how many stars are out in space, why is it that we aren't constantly seeing supernovas in the sky?

I understand that a lot of the stars we see today aren't there anymore, I just don't understand why we don't see supernovas very often

Well not all stars die out through supernovae and we think that only one star in the milky way goes supernova every 50 years or so. It's not all that common. Given the number of stars visible from Earth, we're probably capable of detecting supernovae pretty often, but most just occur too far from Earth to be seen without powerful telescopes.

Why does Venus rotate in the opposite direction to the other planets in our solar system?

The planets conserve their initial angular momentum. Uranus and Venus have opposite rotation from the rest of the planets. This is due to the impacts by asteroids in the early years of their formation. These impacts have probably reversed their rotational direction.

ELI5: How do credit card rewards work, and can I really get free flights and such just by spending money?

I only have one credit card right now, which I am using to slowly build my credit by buying gas each month (anywhere from $75-$125 a month). I do not really know anyone who uses a reward card, but I've heard plenty about frequent flyer miles and other rewards and such. How do these cards really work?

Credit card companies make money in 2 main ways; 1) If you do not pay of the balance at the end of every payment period (usually a month, but there might be cards with other terms), they can charge interest. Usually this is a rather high rate. 2) Companies that want to accept payments from credit cards must pay the credit card companies for this. For this reason credit card companies give you gifts for using their cards. If you want those rewards, you'll use your credit card more often, which means companies must pay your credit card company more.

ELI5: What prevents our eyeballs from being able to look left and right at the same time?

Edit: not talking about cross eyed. Talking about left looking left, and right looking right

Eye movement is one of the most complicated aspects of the nervous system. There are 6 main muscles and 3 main nerves that control each eye around 3 axes. As others are saying it's very common for the left eye to look right and the right eye to look left at the same time (i.e. cross-eyed)—this happens when we look at something close to us and is called convergence. However, we are generally not able to make the left eye look left and the right eye look right at the same time. This is due to a connection in the brainstem called the medial longitudinal fasiculus (MLF). This is a difficult ELI5. If you want your left eye to look left, you need the left lateral rectus muscle, which is controlled by the left abducens nerve (cranial nerve VI). If you want your right eye to look left, you need the right medial rectus muscle, which is controlled by the right oculomotor nerve (cranial nerve III). The MLF runs from the abducens nucleus on one side to the oculomotor nucleus on the other side and is activated whenever the brain activates the abducens nerve, so when your brain sends a signal to look left with your left eye, your right eye also gets a signal to look left. Thus in people who are neurologically intact, when one eye moves outwards, the other eye essentially always follows. The MLF specifically can be affected by a variety of neurologic disorders, classically multiple sclerosis.

What makes something 'important?'

Why is literature more important than gossip, philosophy more important than masturbation, world affairs more important than smoking pot etc? AFAIK, the word 'importance' is only useful when used in reference to a goal. So a pair of scissors would be useful if you want to cut pieces of paper, but it is useless/less useful if your goal is to push a nail into a piece of wood, for that you require a hammer. Likewise, if all I want from life is to masturbate to animated high-school girls with dicks, philosophy or literature holds no relevance for me. But in everyday life, it is taken for granted that some things are just inherently more valuable than others. Why is that? Personally, gaming and weed is more fulfilling and holds more relevance to my life than the news or philosophy, but my reasoning might be flawed so here I am.

The best answer to this question for me is simply that those things are considered to be more important because people who enjoy both type of things, recognize that intelectual pursuits are more meaningful to their lives than masturbating. They also masturbate and enjoy themselves doing it, but recognize that it is a far less transcendent pleasure. In a similar way, a dog may look at your passion for video games and wonder what's so special about video games, when you can run around in the park all day. However, you know the dog would think this because the dog is not intelligent enough to understand and appreciate the complexity involved in playing video games. If he had the capacity and willingness to invest time in video games, he would probably end up finding video games more important than running in the park, because video games stimulate more developed parts of the brain. But, in the end of the day, if you don't like video games, that's fine. If you don't enjoy philosophy that's fine. To each his own.

PhDs who successfully landed a job in academia: how's your workload compared to that of a PhD student?

Are your responsibilities as time consuming? Is your mind constantly set to work, due dates and what needs to be done next? How's the pressure to meet the job requirements vs the usual PhD pressure?

Postdoc was fine -largely like an extended PhD although this depends mostly on what your PhD was like and how much academic freedom you're used to. Tenure track is an unending hell, where you switch from grant deadlines, to brief moments of research, to service and to teaching. The pressure continues to be largely self inflicted. But everything takes up so much time.

CMV: The Concept of Men Having To Be the Pursuer In Relationships Is A Stupid Idea Meant to Control People

Its forces men and women to form life and morals around a societal idea that is designed to force people into roles. If you want to be approached by anyone, you've got to play this Alpha Male Dance, and force people into being interested. I've talked to many a person, after being friends with them so long, who give the "If I knew you were interested, I would have given you a chance earlier." type talk. I'm a 6'2'', decently well built guy; called pretty boy and other slightly demeaning, if not just jokey or flirty things. I'm demi, and I've got to have a connection, and the only way to have that is if the person meets me at least halfway. Only thing I'd say I'm missing that others could provide is being well off financially; born into a poor family and poor state. Like walk towards me with intent, and you have my full attention. I want to know you, but society says I should leave that for last, and is total mind washing BS IMO In regards to dating apps, If I'm presenting myself in any fashion, clearly I'm looking for something, use your head. I'm not going to walk into a McDonald's looking for a steak; you know where we are. Taste is subjective, so I know others would want to be approached too. People are too afraid to be open and emotional. But I can accept that I'm wrong on this, so im listening for other perspectives. Not Validation please. Edit: Tfw you're downvoted without any discussion. Edit2: I'm realizing how far leaning some people are. Some comments are based strictly on emotionally personal growth; some are ITS SCIENCE. Can't the two be combined? Am sleep, answering back ASAP Edit3: I agree my view is brought upon by childhood raising, alot of the current day "be yourself, yadada", and a healthy dose of wanting to be more positive in general when it comes to humanity. Though hearing incel-lite is a bit harsh, you are entitled to your opinion. Edit4: My biggest issue with most reasonable responses is that humans constantly do things that go against that natural instinct. We've had social constructs and unspoken rules such as the "Golden Rule". If we were and are meant to be the pursuing role, whats with the influx of different sexual orientations? To play "The Game", we really either fully go into it, Alpha Boy Prime, or we dabble and ask why it doesn't work. Makes me feel as though I'm the broken one here; wanting to not as much be picky but interact with those who have the same mindset of I want to know the person. Edit5: Its not some evil Saturday morning cabal, its more along the lines of a mix of religion, media, and society, though things are changing. Like yes, its been proven from a scientific standpoint why we are like this, but saying that things are only because of that is naive and very narrow minded. This is not an Occams Razor topic; its not "That Simple" Edit6: By whom is difficult, potentially multifaceted (culture, tradition, religion), potentially extremely simple i.e. nature. Whom to control is easier; EVERYONE. Why can't you like both masculine and feminine traits? Isn't being "balanced" the end goal for human mental development? I have to chase because my and others biology apparently says I must according to science, while according to religion and many societies, I must take up the Mantle of Man. You can be more advanced than that. But what is a Man really? Being brave when I need to be? Sure, easy. Stand up for others in crisis situations? Always. Be some Omega Chad, slapping my dick on things to mark my territory; This is MINE? Fuck that. I am deeper than that; apparently most arent. Edit7: I have some id like to Delta, but I'm reddit incompetent, (on mobile at least). View isn't entirely changed but it has advanced. What I perceive as control is mostly circumstantial, and people just kind of naturally go into the flow when it comes to these types of issues. I am just weirdly different, its ok that I am, and those who lean into only (psuedo)science explanations, true or not, lack E.I. Embrace both and grow lol Edit8: Last one possibly, this entire paragraph blew me away and is eye opening. "I'd also like to reference someone who addressed the idea of other minds. You want people to approach you, despite their personal inclinations not to, for reasons they don't seem to associate with you, but you identify within yourself. How is anyone supposed to see who you are without seeing who you are? And if your the type to stay stush in a corner, angry with the lack of interest that your rendering, I suggest a different approach. If you're looking for it, it won't come. Go out with some friends for the purpose of hanging out with your friends, your energy will speak for itself and whoever finds it attractive will make their way over. Otherwise, you might have to do the talking. And if the conversation dies almost immediately, as you described somewhere in the thread, they're just not for you. Or...vice versa." It never ends lol. If there's anything that comes out of this, outside of my views, I hope someone reads this and some of the wonderful posts, and grows. I want people to be better and truer to themselves, rather than listen to what others say they should be. Final Takeaway: I need to stop using Reddit. That is true wisdom.

From the perspective of an evolutionary psychologist these different behaviours from men and women with regard to finding sexual partners are cognitive biases and adaptive behaviours. They aren't rules created by humans that are unique in humans. Many other species have similar behaviours where the male pursues the female. In these species the cost of baring a child is disproportionately on the female because she has to undergo a gestation period and often raises the offspring. This means that the repercussions for poorly choosing a mate are more costly for the female than they are for the male. If a female makes a bad choice of mate, she is stuck with the responsibility of gestation and raising sub par genetics whereas if the male made a poor choice he just moves on to the next female. As a result of the disproportionate costs of poorly judging the quality of a mate, females tend to be more cautious and conservative whereas males will rarely pass up an opportunity for sex. In humans, specific cognitive biases have been identified. Women tend to underestimate a man's commitment and men tend to overestimate a woman's interest. By the way, monogamy or being lifelong partners is also an adaptive behaviour found in many species. The idea that it is purely a human social construct is ignorant. This is because while a male might pass on his genetics by sex alone, the survival rate of his offspring will continue to rise if he helps to raise them. The chances of his offspring having more offspring will also increase and that is the ultimate goal (perpetuating your genes).

[King of the Hill] Is it ever fully explained why Cotton hates Hank so much?

There's a few factors. Cotton went to war at 14 and isn't very well adjusted emotionally. He doesn't just struggle with emotional intimacy, he has contempt for it. Cotton dragged his ready-to-pop pregnant wife to a Yankees game as camouflage for an assassination attempt on Fidel Castro. Hank ended up being born in New York City in the ladies room of Yankee Stadium and Cotton hates this. He knows it's his fault that Hank wasn't "born a Texan" but still takes it out on him. It's been shown on a few occasions that Cotton doesn't REALLY hate Hank, like when President Jimmy Carter got him to admit it. He's still an angry old SOB though.

[MCU] "I have defended Asgard and the lives of the innocent across the Nine Realms since the time of the Great Beginning." So...did Odin just not notice the major incursions on Earth by the Skrulls and the Kree?

During the events of Captain Marvel, Earth, one of the Nine Realms, becomes the site of a (relatively by Earth standards) major conflict between the warring Kree and Skrull Empires. An invasion by several Skrulls and the presence of a member of Starforce, one of the Kree's most elite military forces, seems like the kind of thing that would need "defending". This seems to be a huge violation of the sovereignty of an Asgardian protectorate. Did Odin simply not notice this? Did he not care? Did he not want to risk drawing Asgard into the Kree/Skrull War?

Heimdall was probably monitoring the situation and telling Odin that everything was cool. Keep in mind that up until Ronan arrived Earth wasn't really in too much danger, and when he did appear Captain Marvel already had everything under control.

ELI5 How are we able to charge our phones wirelessly, and why isnt that technology being used everywhere?

Wireless charging is done through induction. When you run and electrical current through a coiled wire, you generate a magnetic field around it. Conversely, when a coiled wire experiences a change in the local magnetic field, it generates a current. So your charger runs an alternating current (AC) through a coiled wire. This generates a rapidly changing magnetic field. Your phone has a wire coil in its induction charger "module". This wire experiences the changes in magnetic field, which generate a current in the wire. This current is then used to charge the battery. The reason why we can't use this everywhere is that the power you can transfer with this method doesn't reach very far. Also, the more of these changing fields you have going around, the more likely for something else to be impacted, since this will induce currents in any wire coils, even if in other electronics.

[Star Wars] Has Vader ever been shown to use the buttons on his suit? In comics, animation series, movies?

He can use them, but everything is set how he likes it. Remember how mad you dad got when you messed with his car seat, adjusted his wheel, or fucked with the radio levels? Now, Imagine your dad was burn to a crisp, and able to kill with a thought. Needless to say, his buttons don't get messed with often.

[Marvel] So, the Spirit of Vengeance chose me, but I have a rather... unique taste in vehicles. Can I drive a Yugo?

If not a Yugo, what about these? * A pogo stick * a spaceship * a Ford Pinto

The Ghost Rider can ride anything to get from point A to point B. A previous one even had a horse as a mode of transportation. It's perfectly reasonable to use a Yugo, a pogo stick, a spaceship, or a ford pinto as the Ghost Rider and have it undergo the expected transformations.

ELI5: What is Learned helplessness and what is a typical example of it in today's society?

Learned helplessness is esentially when you try something and either fail or are told you failed so many times that you stop trying. A great example from the animal world is that young elephants are often chained with an ankle restraint to a pole. They learn that that ankle restraint is strong enough to stop them from moving. When they get older they still think this. You will sometimes see at circuses full grown elephants with ankle chains tied to a stake that could never restrain a full size elephant. But they don't try because they have been taught it isn't going to work. One big area of child development is in growth vs fixed mindset. Fixed mindset is the idea that you are either good at something or you aren't. If a kid is told enough times that they are dumb, they will believe it. They won't try. They'll fet bad grades because they didn't try. Bad grades reinforce what they'd been told. (Ironically, being told you are smart too much can lead to totally different issues and anxieties). Growth mindset on the other hand emphasizes effort and improvement. You did well on the test, you must have worked hard. You didn't do well, you can do better next time with more effort, etc. It emphasizes success as a process, and one driven by internal effort (not ignoring that it can be aided no doubt by some people's natural abilities and hindered by natural disabilities) and one that can therefore be changed in the future for better or worse through effort.

ELI5:Why are maps and nearly all pictures of earth from space oriented south to north?

I understand the linear orientation is probably driven by the poles. But what about the solar system, we look at everything from our sun to neighboring planets the same way...was it by chance or early astronomers drawings? Is it something to do with direction of spin/orbit?

It is only by preference. Most of the continents are in the North part of the globe. Mapping software can now make maps with any orientation. You can use Google Earth to show you the world oriented in any direction. Producers of maps are taught to include a directional sign, usually North, on the map to help with orientation. But so many maps are now made by people who are not professional cartographers that this tradition is fading.

Eli5: Rehydration clause in boxing

Boxers want to box someone their own weight (or smaller). The weigh-in occurs many hours before the fight. What can happen is, a 165-lb boxer can sweat out 13 lbs to make the weigh-in limit of 152 lbs, then eat and drink themselves back to their normal weight of 165 before the actual fight. If his opponent really is 152 lbs then he's now at a disadvantage. A rehydration clause puts a limit on how much a boxer's weight is allowed to increase between official weigh-in and the actual fight.

CMV: Given that no ayatollahs or imams or Islamic scholars have come out as condemning what is going on in Iran, it is reasonable to assume that the events in Iran are representative of Islam

I have seen many anonymous Muslims online claiming that the actions undertaken by the Islamic Republic of Iran are not Islamic. There are different ways to determine what is Islamic and what is not. One way is to read the Quran and decide. I don't think this is a real option for atheists or other non-Muslims. If you don't believe in anything written in the Quran, this is going to color your perception of it, probably negatively. For example, I personally believe that the Quran does agree with what's happening in Iran, and this is one of the reasons why I am not Muslim. However, someone who is similar to me in most ways (in terms of political leanings and worldview etc) except that they are Muslim, will say the Quran does not agree. There are also many Muslims who say the Quran DOES agree with the various acts done by the Iranian government that are too vile for me to even repeat. An example of such Muslims are Ayatollah Khamenei, a well studied Islamic scholar. There are many other Islamic scholars supporting the regime. I haven't seen any speaking out against it. (I will award deltas if anyone finds a confirmed Islamic scholar actually condemning the regime). As an analogy, consider the doctors out there who are saying the COVID vaccine doesn't work. Some of these are real MD doctors. In the real world, many MD doctors have come out to speak against this and have made it their campaign to make it clear the vaccines are safe. If there were more MDs saying it's unsafe than safe, all of us would assume it's unsafe (or so I hope anyway). But the situation in this scenario is even worse than that. It would be like if there were only laypeople who have an interest in health but no formal education of any kind coming out and saying the vaccines are safe, while MDs are either silent on the issue or are saying vaccines are unsafe. We would ignore the laypeople who are coming out saying they've "done their own research" in favour of the expert, so why are we listening to lay Muslims that have "done their research" despite Islamic scholars saying something else?

Someone else can explain the “blame all for one” issue. But I’ll add you’re asking “Islamic scholars — professors and interpreters — and preachers — to condemn how one government that adheres by its definition of the minority sect’s view of Islam enforces its criminal laws. Shiite Islam is massive, but Shia and Sunni Muslims highly distrust each other’s interpretations of scripture and history. They do not even agree who succeeded Muhammad. Shia Islamic national law isn’t isolated to Iran. How can you pin a religious police force’s execution of a law in one country on more than a billion Muslims.

ELI5: What is happening internally when a boxer 'loses his feet' ?

When a boxer has the difficulty to move around, what exactly happened inside his body and where did he need to get hit in order to 'lose his feet' ? Clarification: I don't mean a knock out. I mean not being able to move around freely; it's like like your legs are resisting. (edit: word stuff)

Well aside from the whole "O shit that hurt!" part of the brain when you take a massive body shot. It's also a biological reaction. When you receive that kind of trauma to the internal organs. You're body reflexively goes into survival mode. As it's not sure exactly what the hell just happened. So it ramps up blood production to start healing or clotting blood if it needs to and it's starts loading those new blood cells with more O2 to aide in this process. It also starts to constrict the blood vessels of the extremities to increase blood flow to the torso and the vital organs of the body. A similar process to that of hypothermia. It then decides that the "pain" is to distracting so it starts shutting down nerve function and your receptors. So fundamentally, your legs and arms lose circulation briefly, reducing the O2 to those cells and nerves and then the nerves that are really important to, you know muscles movement and stuff are turned off. You body doesn't know your a dumb ass boxer. It's just knows, "Holy flippin' hell something just hit the crap outta us! Save all the inside stuff, toes are for CHUMPS!" Is basically what happens.

[Harry Potter] Why is the Ravenclaw common room so easy to get in to?

Ravenclaw may be the house that values intelligence the most, but that does not mean that everyone in the other houses is stupid *cough*Hermione*cough*. And if the door asks a riddle that one could reasonably expect a first year Ravenclaw to answer, then surely one of the older years in another house (you know, those who would have reason to go breaking in to other houses' dorm rooms) would be able to get by without much trouble. Or, to put it another way, every other house has a secure password, while the house of the most intelligent gives you a clue on how to get in.

[](/rscootaplease) Rowena Ravenclaw didn't care about security so much as keeping the dimwits out. The other founders all played their political games and tried to keep one another from learning their secrets, but Ravenclaw just wanted to create a sanctuary for the clever and the wise. It didn't really matter to her whether those clever and wise people were in her own House or in Gryffindor, though of course nowadays an intruder to the Ravenclaw common room would get in a lot of trouble if caught.

[Star Wars] Why doesnt the Clone Army or the Droid Army use proper military tactics?

There are numerous examples of large scale battles in which both armies refuse to use standard military tactics, and instead march towards the opposite army in large tight columns with shots being fired straight at them, also completely disregarding the danger of thermal detonators being thrown into a tight crowd. It doesn't exactly take a Ghengis Khan to realise that marching towards enemy fire in tight columns is an absolutely terrible tactic - so what were the military leaders in the Clone Wars thinking? Post Clone Wars, it seems military leaders fortunately changed tactics and began using more effective battle tactics (ref: Battle of Mimban, the use of trenches, flanking, artillery). But this doesn't answer the poor military tactics of before that then - especially as we know that Clones and Droids were programmed to avoid themselves coming to harm (i.e. they had a sense of self preservation).

Because Palpatine's ultimately in charge of both sides, and he doesn't *want* to win any battles. What he wants to spread chaos and destabilize the republic so he can later swoop in and reform it into the empire. For this to work, obviously, the republic can't win. Then they've stabilized and all is fine. But they can't lose either- his whole plan is based around his power as senator, and the occupation and dissolving of the government where senators are a thing would obviously put a stop to that. No, what *he* wants is bloody, horrifying battles with massive death tolls that fail to accomplish any tactical objectives, spreading terror and damaging infrastructure but not actually bringing the war any closer to an end. So he gets the generals to go for terrible tactics- maybe by ensuring idiots and minions are promoted, maybe by spreading convincing sounding but terrible military theory, maybe just old fashioned corruption. There's lots of ways to subvert a military. Come the later movies, of course, both sides *are* trying to win, so they use real tactics. But here, it's not a real war. It's a ploy by someone playing both sides, and he's trying to make sure it goes as long and as bloodily as possible before he makes his play.

Pro-life friend has questions about birth control and egg fertilization

My conservative Christian friend is getting married and has heard that there's a tiny chance birth control will destroy a fertilized egg. She believes that life begins at conception. She is planning to only use condoms, but gave me permission to do some research and present her with a pro-life argument for birth control. I've been doing that research, and I just came across a statement that "fertilized eggs fail to implant all the time; it's not the same as abortion." What does this really mean? I am not entirely sure that this is the right subreddit, but I couldn't think of a better one.

It means that a fertilized egg often is not sufficient to be pregnant. Many pregnancies do not get to the stage of an implanted egg and many of those that manage to implant in the uterus still do not get past the 8th week. Basically, there are so many things that can go wrong between intercourse and birth it is a wonder any kids are born at all (and healthy ones at that) :-). If the pill works correctly, though, there should be no egg ready to be fertilized present. However, if one happens to be fertilized, the pill inhibits an implantation. So, yes, the pill has a tiny chance to abort a fertilized egg even if by most definitions this would not be seen as an abortion as the pregnancy had not *really* started in the sense that you are not immediately pregnant after an IVF procedure....

[LOTR] What does the ring show/say/feel to frodo and others whom have it that makes them act so differently or have PTSD?

Basically the ring subjects its wielder too intense subliminal brainwashing. When Sauron and made the One Ring he put a part of himself into it which is why it could only be destroyed in the fires that made it and when it was destroyed it killed Sauron. That bit of Sauron slowly eats away at you compelling you to act towards his benefit with the ultimate goal of making it back to Sauron. The longer you have it in your possession the stronger that becomes. Even more so if like Frodo Bilbo and Gollum you put it on.

[Dog With a Blog] How the hell does Stan type with dog arms?

Easy, he's an early 40k psyker. Before the Age of Strife, most humanoid Psykers were unheard of, but there were dog psykers before since they had been a species for much longer. Using psychic power from the early Warp, he is able to take control of the computer's machine spirit. Yeah, that's how it goes.

[The Incredibles] Frozone is unable to use his powers due to a lack of moisture in the air. Upon being confronted by an officer he drinks a relatively small amount of water and is able to use his powers again to encase the man in far more ice compared to what he drank. How??

​

You forget they are standing arguing in the jewelry store for a bit. There's probably a fair amount of water left in the air there as that store wasnt on fire. He probably just needed the water to kickstart his powers with a little bit of hydration.

Has the thickness of phones reached a physical limit?

Not much more contect needed I think. (If yes, what stops us?)

There's nothing directly keeping phones from getting thinner. There's a number of things that will make it unlikely anybody would decide to, though-- the biggest of which is probably the camera. Cameras are effectively setting the phone thickness limit right now, to the point where the common design workaround is to make the camera stick out. Without the camera, you could take all the parts in a modern phone and lay them out so it was even thinner. Even something like the new iPhones could be thinned out-- their innards are still a sandwich of multiple layers. At a very simple level, you could just put the battery, screen, and mainboard next to eachother instead of on top of eachother. The result might be ugly and wide and so forth-- but it would be substantially thinner than currently without having to even invent anything new.

If I we were to place an optical telescope 100 light-years away from Earth, and look back at it, would we see Earth 100 years ago?

This is something that recently occurred to me. Assuming perfect conditions, if an optical telescope with unlimited power were to be placed 100 light-years away from Earth, then pointed back at it, would we be able to see life 100 years ago? ~~Also, I'd add the "Astronomy" tag, but at the top of the submission page it says 'Add flair to your post by clicking the "flair" button under your title.', and I see no such button.~~ **edit:** Found the button.

This is correct - a telescope that is currently 100 light-years away from Earth would see Earth as it was 100 years ago...but there are a few caveats: - First, you'd need a big telescope - like, *really* big. To even see the Earth near the Sun, you'd require a telescope hundreds of times larger than anything that's ever been built. As it stands, the planned James Webb Space Telescope could not spot an Earth-sized planet 1 AU (the Earth-Sun distance) from our nearest neighbor, Alpha Centauri, and 100 light-years is about 25 times further. - Second, seeing Earth as anything more than a single pixel would require another few orders of magnitude in telescope size. - Third, you couldn't carry a telescope out to that distance from Earth to see into our planet's past, because the trip would take greater than 100 years. (since you are confined to speeds less than the speed of light).

ELI5: Why do so many Americans blame Obama for practically everything?

Because most American citizens have very little idea of how their government actually works, and how limited the president's power is, domestically and economically. The president is the most well-known governmental figure, and it's a lot simpler to blame him than to go watch C-SPAN or check voting records and see that it's actually your representatives and senators who are screwing you, in many cases, *specifically* because they know you'll blame Obama for it and they want his approval rating to go down.

[House of Cards] Is Frank Underwood able to deliberately break the 4th wall, are we simply seeing his thoughts in those moments, or is something else happening?

Before tv series there were movies and before movies there were plays, before plays there was your buddy telling you what was going through his head earlier when you both were at that thing. Its called an "aside". As in taking the audience aside to fill them in on more details. He's not breaking the fourth wall, he remains in his own universe. You are the one who has left yours.

Why isn't there a version of birth control for males?

There is a form of male birth control accomplished through a vasectomy. This is the equivalent to a female having her fallopian tubes tied. If you are referring to hormonal methods of birth control, the reason why none are used for men is about the side effects. In the female menstrual cycle, estrogen and progesterone control ovulation - by artificially manipulating these levels "the pill" prevents the maturation of the ovum. If androgen deprivation were used on men (decreasing testosterone and inhibiting sperm growth) they would experience severe side effects, such as impaired muscle maintenance, increased bone fragility, sensitivity to heat and the onset of other "female" traits. This isn't to say that "the pill" does not come with its host of side effects, but these are generally observed as more tolerable.

[40k] never played, can somebody explain the psychic orcs to me?

The most I know is the story about a guy who was kidnapped (or surrounded?) by orcs and without any ammo, but because the orcs didn’t know he had no ammo he just pointed his gun and shouted “BANGBANGBANG” and the orcs... actually died? This one story has made me somewhat interested in 40k for no reason other than sheer bullshittery But how do orc psychics work? Is it all orcs or just some? What’s the gist of their power?

All orks possess a low level of psychic ability that contributes to the gestalt psychic field. This means that the larger the assembly of orks, the more psychic power there is to create effects that mirror what the orks expect. For example, a small band of a few dozen orks might paint their trukk red because they believe that red ones go faster. They will be able to channel enough energy to actual make a red trukk go slightly faster than other trukks of similar make. On the more extreme end, a space hulk with a massive greenskin infestation may have orks walking on its surface without void suits because they forgot that they need to breathe. It's the psychic field that is keeping them alive in that case. There is also a caste of orks that woeld psychic abilities, called weirdboys. They are able to channel the energy of the psychic field into the material world intentionally to create a multitude of desired effects.

Is it possible to reverse yellowing of teeth by brushing harder? Or is tooth yellowing permanent?

Edit: wow, calm down mods! I'm seeing a lot of helpful comments being removed.

Staining isnt the only reason teeth turn yellow. Enamel is white-ish but it's not completely opaque. Dentin, the material underneath your enamel is naturally yellow, aging and natural wear thins your enamel making the dentin more visible. If you brush too hard you could just end up stripping away more enamel resulting in even yellower teeth.

ELI5: If so, what's the difference between a Sith Lord and someone using the dark side of the force?

A Sith Lord is trained as a Sith Lord. He or she learns not only the Force, but a certain code of ethics as well, questionable as they may be. Someone who uses the Dark Side of the Force is just someone who has figured out how to use the Dark Side of the Force. Most likely, they were trained, at least to some degree, by Jedi, but chose not to follow their code.

ELI5: Why is hand-made stuff "better" than machine-made stuff?

A lot of high end suits and shoes brag that they're hand-made. Why is this better than machine-made, where the machine will do things precisely, while the man making it could make mistakes?

Machine-made generally means something that's designed for mass manufacturing. There are shortcuts in the design, because it has to be efficient to manufacture in quantity. The materials involved also have to be suitable for mass manufacturing and, ideally, inexpensive. A good craftsman can do much better work. This involves skill, time, and generally better materials, because there's no point in wasting skill and time on inferior work.

If I lie in bed all day and don't eat between 10am and 6pm, I feel ravished and will go far out of my way for a meal. Every single night I lie in my bed and eat nothing between 10pm and 6am, and I feel no urgency to have breakfast. What's the difference?

Insulin levels rise and fall depending on your sleep schedule. Leading to hunger and fasting. In fact recent research in mice showed those mice that only ate during "mouse day time" for a set amount of time. 8 to 12 hrs. Maintained weight better then those who forged anytime.

How straightness is achieved in construction?

How did we develop first straight objects? For example to create a ruler we need some straightness reference(I assume). Of course nothing will be 100% straight but when you think all the delicate machinary such as medical devices and the machines used in the space we must be pretty close. Is there a way to geometrically approximate to a straight line without a straight device?

simplest straight lines are a taut string or a flat water surface. early surfaces were just created by hand. our precision has increased over time. we never hit perfectly straight, just straight enough to suffice.

ELI5: Why do video game developers choose to only release games only on some consoles/PC but not others? How much more work does it take to program a game to operate on a different console, say Switch vs Playstation for example?

It takes a lot of work. Consoles tend to have less power than PCs and each of the major consoles uses a different operating system. PC and Xbox share a lot of internal code, but PCs have thousands of combinations of parts, compared to the consoles all using the same processors. For a small studio this is a lot of work. In general game companies have two options: make a game run okay on all platforms or really well on one. I’m a PC gamer, but I’m shocked at how well God of War and Horizon Zero Dawn run on the PS4. Knowing exactly what hardware your game will run on is a major help to optimization. And also, game companies sometime sign contractors to only release on a single console. Sony may pay a company a million to not sell their game on the Xbox. Or in the case of Bethesda: Microsoft owns them, so they’ll be making almost exclusively PC and Xbox games from now on. There you go, it takes a lot of people and time to make a good cross platform game, and there’s a lot of money involved in keeping games from getting ported.

When a video game runs at 60 frames per second, does that mean only the display shows what happens every 60th of a second, or does the game have markers that take inputs and produce outputs only at those times too?

For example, I know that the CPU that's processing everything can make a cycle every couple billionths of a second, and all though it would take a lot of them to produce a result, taking an input and sending it to the game should be very fast, and be able to happen in between frames, right? So for instance say there's a certain game that runs 60 fps, where the simple objective is to press a button before your opponent. If you press it after exactly 101 ms, and your opponent presses it after 115 ms, since the next "marker" for the game would happen at 116.6 ms, would this produce a tie, or would you win? I would imagine that the CPU could tell you pressed it first, but when working with emulators and such, everything is cut into individual frames.

It depends on the game. Minecraft will draw frames as often as your GPU and your monitor can handle, but the physics system only "ticks" once every 1/20th of a second. Time happens in 50 ms slices. If you and a friend both hit two buttons to start two redstone clocks at the same time to within a few milliseconds then they will be perfectly simultaneous. If you are interested in breaking things for fun or testing purposes then the weirdness of discrete time is a good place to start looking for bugs.

[General] Everyone is envious of Superman's Kryptonian powers and Spider-Man's spider-like abilities, but what superpowers are the most overrated?

Fire powers. Like... yeah, if you had Human Torch level immunity or Pyro's manipulation, it could be awesome! But if you had Avatar level fire bending, you're more than likely going to end up burning everything and everyone around you. Also, power copying or cancelling... not only is it lame for stories, but if no one else had powers, you're just a fucking muggle. Flight has a lot of inherent problems that would limit your ability unless you had other abilities to compensate for the temperature, pressure, oxygen levels, collisions, and it's basically useless unless you can fly at a velocity (at least) comparable to your fastest running speeds.

If you pointed a powerful laser (like the ones the military are using to take down missiles) at a mirror would it burn through the mirror or bounce off it?

Well, even a really great mirror isn't 100% reflective, so it will always absorb some of the light. If you pump strong enough, yes, you'll start to heat up the mirror faster than it can dissipate the heat and eventually it will melt. Another thing to consider is that the reflectivity of a surface depends heavily on the wavelength of light. A mirror that might be reflective to visible light, say 99% reflective, might only be 5% reflective to infrared light. So if you were trying to build an anti-missile laser or a laser-proof missile hull, for example, you'd want to take that into account.

ELI5: why do LED torches have multiple small LED's instead of one big one?

Some of them (the nice, expensive ones) do have a single LED, such as Mag-Lite. Low-output LEDs are much less expensive to produce, so cheap flashlights often will have 25-50 of them (a dead giveaway is their very bluish tint); their overall light output is typically less than those with a single LED. When purchasing, look for how many lumens the flashlight produces, not how many LEDs; more lumens = brighter.

ELI5: Why aren't other animals as freaked out by bugs and creepy crawlies as humans?

Are we the only ones afraid, rationally or irrationally, of bugs?

Fear is generally a learned response in humans rather than being present from birth. Whenever a human is observing another human as being a role model, the observer sees the response taken by the role model, and is more likely to recreate that response in the future. Because of this, it's easy to pass on your fear of bugs to another person, as long as that person's subconscious processing thinks you are worth learning from. On the other hand, some fears are present from birth as a defensive response to tell an animal to run away when presented with a dangerous situation. Most animals don't fear bugs simply because bugs don't do anything to the animal. But if you put a cucumber behind a cat while it's eating, it will panic and run away because it is born with a fear of snakes, and the cat's innate processing mistakes the cucumber for a threat. It's likely that our original fear of bugs did come from the knowledge that certain bugs can have bad or even deadly effects on us, which then spread the mentality that we should be afraid of all bugs. For an animal to fear that same bug, it would have to be because of a survival instinct, unless the animal somehow also learned to fear bugs. Edit: apparently the cucumber/snake thing with cats may not be 100% scientific, but it was the first example that came to mind when thinking of innate fears.

[Star Wars Legends] What was the point of the chosen one prophecy?

In legends, even though Anakin killed Palpatine on the second Death Star, he only truly died during the events of Dark Empire. The Sith would also still be around for at least 100 more years. Considering this, what was the point of the prophecy when the Sith still exist and Palpatine only died years later and not due to Anakin.

The imbalance came about because, through Palpatine's machinations, the Dark side had grown incredibly powerful, blinding the Jedi and other servants of the Light to his intentions, and even some of his actions. The Light was crippled by bureaucracy, negligence, tradition, politics, and a slew of other things. The Dark side had no such impediments: the Chancellor (or Emperor) made the rules. The (first) death of the Emperor by Anakin's hand brought balance to the Force. It put a stop to the Sith, at least in that one moment. The Emperor was dead, Anakin turned back towards the light, and all that was left of the Sith were a few scattered apprentices. When Luke put together the new Jedi Order, that allowed the Light side to grow and dominate, and thus they were able to fight the Sith on almost equal footing. Yes, the Imperial remnant fought on, and yes, Palpatine kept playing the part of the mole in a game of whack-a-mole, but the Jedi weren't as blind anymore. They didn't have to hide. At times, they even had the entire Republic behind them. Knowledge and training in the Force was allowed to grow and diversify. It wasn't a perfect balance, but it was better than the utter oppression of the Force that existed under Palpatine's rule.

If Earth's atmosphere is primarily nitrogen, then why did life develop using oxygen and carbon dioxide?

Something that is not brought up in many of the comments here is that life did not develop using molecular oxygen (O2) at all. The large concentration of oxygen in the atmosphere is actually the result of biological activity (carbon fixation from CO2 and reduction of iron oxide before that) and not a prerequisite for it.

[Marvel] If i had a way to contact Galactus, how hard would it be to convince him to make me his herald?

If you can actually contact Galactus, you're pretty much halfway there. He's been known to force Heraldry onto various people, causing them to lose their memory and only want to serve him. If you simply ask, it's very possible he'll say yes if he doesn't currently have a Herald or has one that's openly defying him.

ELI5: Why does it feel colder inside in the winter even though the thermostat says the temperature is the same?

Humidity plays a big part in temp perception. In the winter, outside colder air cannot hold the same amount of humidity as hotter summer air, so typically your house, while the same temp, has less humidity. Even if you have a humidifier, it's tough to match the potentional summer air humidity. That difference eventually makes it into your house. The lower the humidity, the more moisture evaporates on your skin, making you feel cooler despite the temp at the thermostat saying the same.

ELI5: Why is it when I eat or drink some things I feel like pooping within a few minutes when food and drink take hours to digest?

Eating or drinking something kick your digestive tract into motion. Lots of enzymes start squirting into your intestines. Lots of muscle contractions from your stomach to your butthole getting things moving along. Some chemicals in food (caffeine in particular) are *really* stimulating to your intestinal muscles. When those start working overtime, you suddenly get the urge to go, like, now.

Blackballed by department for reporting gender bias to the chair... should I stay or should I go?

This is a throwaway account for obvious reasons. I’m a female PhD student in a leading department in my field. I started my PhD in a lab that was a top choice for me and I was really excited about it. Not long into that lab experience, my adviser made direct comments about my ability to succeed based on my gender. These were made verbally, just me in his office— so unfortunately, no witnesses. Despite the awful comments, I trudged forward thinking I didn’t really need to change my adviser’s opinion of all women— just me. So I thought if I could prove my ability to stack up to the male students who already had my adviser’s approval, then maybe I’d be just fine. You can guess that it wasn’t fine and the bias continued no matter what I did, so I did the only thing I could and I left the lab. The only other lab with an opening was one that was about as far left field from my interests as one could get— but it was my only lifeline to stay enrolled— so I went for it. You can also guess that that experience wasn’t going to last long term... and it didn’t. I simply didn’t have enough in common with that lab to forge a path forward. In a stroke of luck, though, a professor in a different department entirely took an interest in me and offered me a place in their lab.... complete with an offer to fully transfer departments, which I have pursued and is where I am currently. At the same time, though, I also realized that if my academic path was so irrevocably altered by the first lab, it was the morally correct thing to say *something* to *someone.* So I reported my experience in the first lab to the department chair in a private meeting behind closed doors. Instead of taking the report gracefully, the chair responded by convening a meeting of the faculty— including the adviser in question— and telling them everything I said (including telling them it was me, by name). The faculty subsequently ruled to ban me from continuing to work on ongoing research projects with my original adviser— projects that I was otherwise supposed to see to completion. Specifically, the decision is going to cost me publication opportunities that were fully intended for me to write. Given this response by the faculty, I involved a university office, which is investigating. The investigation is ongoing, but a high-ranking university official has already indicated that the university position will be in favor of escalating this to a full Title IX complaint. So.... here’s the rub.... I’m in a new department, which is nice... but my original department holds a lot of clout in my field, and— even having switched departments— my adviser and I had always expected to include several of them on my dissertation committee and to ask to use equipment/resources in that department. It’s too hard to explain— and would make this post even less anonymous than it already is— but the intention is that I will apply for academic positions in the same departments as my former department, not my new one. The former department will always be the best fit for me and my background. The new department is okay only because of this one particular adviser, if that makes sense. If you’ve made it this far... the question is whether it’s futile for me to stay in my current PhD program, knowing I’m blackballed by my former program, which is linked in with all the programs in which I’ll want to apply for jobs someday. Also knowing I may not be able to use any of them on my dissertation committee. Furthermore, my current adviser knows my former department... so it’s not totally clear how all this will affect my relationship with them either. I feel like I’m stuck between a rock and a hard place.... and I didn’t do anything wrong. I want to get a PhD, but I also don’t want to find out at the very end that I was screwed all along. Help!

The Title IX office should eat the first department alive for their egregious behavior. Given the loss of publications, you have material damages. Are you sure everyone in the first department agreed with the decisions pushed by the chair? You may come out fine if it's just the old misogynistic bullies that are against you

If gravity is a property of spacetime, why are we trying to explain it as a fundamental force?

I feel like I sound like a complete idiot asking this. I should mention I have no real background in physics, so I probably am an idiot. From what I understand, we describe the strong force, the weak force, and the electromagnetic force as fundamental forces of nature, with each force being mediated by their own boson (or in the case of the weak force, two bosons). Also from what I understand, gravity is caused by mass bending spacetime around it. To me, it seems that gravity isn't something we should be describing as a fundamental force, and that it should be described as a property of the fabric of spacetime. Are we trying to explain it as a fundamental force because it fits better with the math?

the other three fundamental forces are gauge theories, meaning that they also admit a "geometrical" formulation similar to, but not equal, that for gravity given by general relativity. There are immense similarities between the other three interactions and gravity. Moreover, the geometric picture and the field picture (the one with the gauge bosons) are really equivalent - barring some global subtleties. Finally, the unification of gravity with the other forces is almost a necessity, not just something that would be nice. It is likely necessary to build a consistent theory of quantum gravity. We write gravity and the other forces in all possible equivalent ways so that it's easier to understand possible connections when studying theories of everything. For example, understanding how gravity unavoidably arises as the theory of a spin-2 massless boson (the graviton) made it really easy at the time to recognize that string theory included gravitation. (btw, the weak force has three bosons, and the strong force has eight)