[System] Given the following post, respond as if you're commenting on Reddit:

[User]
Whenever I download a file over HTTP, do the bits come in the correct order? Or are they downloaded in any order and the file assembled on completion.

I am trying to understand the difference between downloading a file to disk vs. using a stream in a programming language like C#.

My understanding of a stream is that it opens a connection and begins transferring bytes of data in small chunks into memory.

**Q1.** When streaming a file like this, do the bytes come in the correct order? I.e. if the bytes were arranged from start to finish on disk, are they streamed in that order?

**Q2.** Then contrast that with downloading a file over HTTP. Does this basically work the same as streaming except it's streamed straight to disk rather than memory?

What's confusing me is how torrents work. Torrents generate a metadata file (the torrent) that divides the target file into chunks which are downloaded in any order. Once complete, the torrent program arranges them altogether.

[Assistant] data is sent sequentially in packets, each packet is formed of a header and a body section, the header contains different information based on the used protocol, a TCP  packet has a sequence number, so if the packets reached the destination out of order, the computer can rearrange them, while a UDP packet doesn't have a sequence number and data can come in any order.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
Is 'sun fire' the same as 'our fire' ?

Well, my question is just that. Is there a difference between the ''sun fire'' (don't know how to state it correctly), and the fire on earth?

Just like you have different ''kinds'' of water (salt, sweet, etc.), are there different kinds of fire?

[Assistant]
No. The heat and light and energy that comes from the sun is the result of a nuclear reaction. The sun is converting Hydrogen into Helium. the Fire on our planet is a molecular process involving the combination of oxygen with other molecules.

Technically, there is no 'sun fire'. It's not fire at all, but a nuclear reaction.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
ELI5: Why do some rocks, such as jade stone, feel cool to touch?

Ive tried to ask Prof. Google but to no avail. This question has been bugging me. An example is the jade stone in jade rollers, where the stone feel cool when out against the skin, no matter the ambient temperature of the surrounding environment.

[Assistant] You don't feel heat but heat transfer. So things that are good at transferring heat will feel hotter or colder depending on their actual temperature. And things that suck at transferring heat like cloth or wood will feel more neutral regardless of how hot or cold they are. It's the same reason why you can sit down in a 90C sauna on a wooden bench but you would burn your bottom if those benches were metal or stone. And the same why your bathroom rug feels nice after taking a shower but the tiles feel painfully cold.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] [Star Wars] Why didn't Yoda share the secret of becoming a Force Ghost with other Jedi besides Obi-Wan?

[Assistant]
Qui-Gon is the one teaching the force-ghost technique, not Yoda. At the end of Episode 3 when they are going to part ways Yoda says to Kenobi that during the exile time an old friend will teach him. Qui-Gon died before mastering it and he has only a voice but Yoda and Kenobi had more time and by the end of their lives they were probably more powerful and in peace than Qui-Gon.

The last three episodes of Star Wars The Clone Wars touch this subject too.

Edit. So in essence, by the time Yoda was able to teach the technique he had no time to pass it to fellow Knights and Masters.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
I'm a black person who doesn't think Paula Deen deserved to get fired. CMV

I don't love what Paula Deen(PD) said but I believe that if we fired every white person uses the n word a lot of people would be out of work. I believe that if we're going to hold PD to this golden standard, then everyone should be held to that standard and we should stop pretending only the most ardent racists use the n word.

If its so terrible, lets crack down on all the n word users. If we're not going to go after other n word users what is the point of pretending we are some kind of progressive society that hates racism and slurs so much. It only takes a few minutes of browsing reddit to come across a racist joke. It's not ideal, but it would be silly to pretend all those people are teenage boys working multiple accounts in their moms basement.

Lets deal with racism, or lets keep pretending it doesn't exist. A witch hunt of just one figure who had the intestinal fortitude to be honest really doesn't help the cause.

[Assistant] The important difference with people like PD is that they are a brand spokesperson:  someone who is literally the face of a product/network show.  There is a difference between having a guy who flips the burgers in the back being racist, and someone who is being put out to the public as "Look at this person.  They are so admirable and respectable that merely having their face on our honey-glazed ham should be reason enough alone for you to want to buy it." or "This woman is the type of person that we want speaking for our television network for hours a week.  She represents what our network is about."  Spokesperson and public icon roles are very sensitive to things like this, because if you continue to use the person after this, you're basically saying "Buy our racist hams" in the public's eye, because an endorsement of her is an endorsement of what she stands for.  This same implication doesn't carry over to normal employees since they aren't being presented as being the personification of everything the product stands for.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
ELI5: Why is it that before an orgasm you have a feeling willingness to do anything, but as soon as the orgasm passes you come to your "senses" (NSFW)

Since the title was getting long let me describe a little better, how come it is that when you are feeling really horny and are either having sex or masturbating you loose the sensation of "caring" about what you normally would and your willingness to do kinkier things is multiplied by like 200%? Im not talking about the after regret of it since I know about that but what causes our brains to be alright with something when we're horny that we wouldn't normally be alright with? And then after an orgasm go back to thinking "Yeah never mind"

[Assistant] According to some studies about human psychology, our disgust response is literally reduced the hornier you are. Which makes sense. Sex isnt really the most hygienic thing in the world haha. But once you're done, your disgust feelings return to normal.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] [Warcraft] Why was there a 10,000 year gap between the first and second Legion invasions, but only a few years between the second and third?

[Assistant]
The night Elves were the dominant, and only noteable race on Azeroth at the time. While the Naga had been corrupted (somewhat) and heroes like Illidan had fallen, the demons had been vanquished with the well of eternity sealed, which was their gateway into Azeroth.

It took 10,000 years for Sargeras to find an individual powerful enough on Azeroth that he could corrupt to open a new portal. With Mannoroth having corrupted the Orcs and making a portal from Draenor to Azeroth, he was given a first chance to conquer the planet, as the Orcs seemed to be on the path to integration into the Legion proper, though they were repulsed twice before the Legion itself was brought in.

The latest invasion seems to mostly be triggered by the time traveling/universe hopping Gul'dan from WoD, the legion has a number of factions in Azeroth now they can call upon for support to lead another invasion, something they didn't have after their initial invasion, and the 10 or so years since the 3rd war the Undead Scourge has fallen (Ner'zhul/Lich King definitely did what he could to undermine the initial invasion even sending Arthas to lead Illidan to the Skull of Gul'dan and kill Tichondrius. ) and the various other tragedies and infighting amongst the powers of Azeroth has effectively weakened them or at the very least prevented them from building their forces like the legion has been doing so.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] What do mosquitoes contribute to the environment?

[Assistant] Besides being tasty bat, dragonfly and hummingbird food, mosquitoes primarily feed on nectar, so are useful pollinators. There may be a handful of rare orchids that are dependent on mosquitoes, and they are the primary pollinators of the cacao tree.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] ELI5: what is the design process of building an application?

[Assistant]
Ex-developer and now IT project manager here. It depends on the size and complexity of the application.

For little wee ones like an Excel macro that processes a sheet or a data-cleansing routine, you usually have an idea in mind of what you need to have happen, so you break it down into steps and work through developing each step. So your mental map of the data cleanser might be: Pick up a record, look at it for these features, correct these features if you find them, put back that record in a new area. Then you build those (sometimes in order, sometimes not), test and tweak it as you go along until it's done.

For slightly larger and more complex apps, such as a simple game, first someone thinks about where they want to go with it, then they write the basics down to describe it to whoever is paying for it to justify getting money (if not themselves). With that concept of the game there, they start breaking it down into what they need to do first - for example, a sidescrolling game needs the ability for the character to stand on something, or a data processing application needs to connect to a data source and read a record from it - and work through that, then meshing out each additional detail as they continue. Sometimes this approach needs a concept demo too, such as if you're going after kickstarter funding. The developer invests some of their time into building a tiny part of the game that will look and feel a little like the end product, then shows it to the people they want money from so that audience can see what they're going to get. Then the now-funded developer gets approval and funding to do all the remaining detail work.

Big projects need teams need a much larger approach. You start with the basics in a story - "it will be a first person science fiction single-player shooter with a machine possession mechanic and will support multiplayer", and then each of your sub-teams on it gets their piece to do once you've decided on fundamentals like what gaming engine you're going to use if you don't build your own, what platforms you're going to target, and who the target audience is (e.g. whether it has cartoony characters or gory exploding ones). The story/script team starts building how the visual world will work and how single-person gameplay will flow by working closely with the art design team, and the technical team weighs in on what's technically possible versus what's not. This is a very back-and-forth process. The multiplayer mechanics team starts working on getting all the send/receive processing going. Then as things work along, all the team leaders meet and check with the boss to ensure they're staying on direction, trading information and changes around, and hitting deadlines, and they adjust as they go along.

The "traditional way" of doing all that organizing, called "waterfall", was to write down and get a signed off list of details before you start coding. The "modern way" is called "agile" and saying "This is what we're pointing at doing this month", getting approval for that, then doing it and figuring out what the next month's work will be like when the time comes. Agile is more flexible than waterfall, but it's also less locked-in, so it's useful for some types of projects more than others.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] What would happen/look like if an alka-selzter was opened up at the deepest known part of the sea? Would the gas behave differently?

[Assistant] At the bottom of the ocean, the sodium bicarbonate and citric acid in Alka Seltzer would still react to form CO2 and sodium citrate.  The CO2, however, would not remain in gas bubble form, since it is vastly undersaturated at 1100 times atmospheric pressure.  If any bubbles could be seen at the point of reaction, they would quickly dissolve into the water.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] ELI5: Why can't we grow back teeth?

[Assistant]
We as a species didn't have a genetic need for it. Those that do (sharks) end up constantly replacing teeth.

Remember our brain is vastly larger compared to most other animals and the caloric input to keep it running meant trade offs elsewhere.

You do realize very few animals have more than one set of teeth anyway. We are lucky we get even two.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
Will consumer grade electronics interfere with an airplanes avionics?

Will my BlackBerry make the plane explode? Because that's what the stewardess implied.

[Assistant] No. Cell phone usage on airplanes are banned by the Federal Communications Commission, not the Federal Aviation Agency. This is because the FCC doesn't want cell phones clogging up network by constantly finding a new tower as the plane flies over them. If there is a safety concern, the FAA would be the ones issuing a ban.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
ELI5:How is tic tac toe such a classic, popular game for something that doesn't guarantee a winner?

Just seems a little silly.

[Assistant]
Many games don't guarantee a winner. Ties are common in almost all sports, from Boxing to Soccer. The remedy is a tie-breaker, which is just another round (or extended time), the same thing that happens in tic-tac-toe.

It's an easy game to play, an easy game to learn/explain, and requires almost nothing in the way of equipment. If you can draw on something, even if it's just fingers in sand, you can play. That's why it's so popular.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] ELI5: Getting computer programs to utilize multiple CPU cores is difficult because the programs have to be specifically coded that way. Why can't CPUs allocate instructions to different cores themselves?

[Assistant]
The main advantage of programs designed for multi-core use is that they can be sped up by running multiple tasks at the same time on different cores. Some tasks cannot be divided up into multiple simultaneous tasks to take advantage of multiple cores.

Imagine the CPU like a restaurant kitchen. The chefs are the cores. Some tasks like a main dish can be sped up this way. It can be divided up into three tasks. One chef makes the meat, one makes the potatoes, and one makes the vegetables. Since they can do each of their tasks at the same time it's quicker to make the meal than having a single chef make each part in sequence.

Now imagine you're trying to bake a cake. You too can divide it up into multiple tasks. Mixing ingredients, baking the cake, icing the cake. However fundamentally these cannot be done at the same time. They have to be done in order. You can't bake an unmixed cake, you can't ice an unbaked cake. So you cannot speed this task up by doing one part at the same time as another.

A good programmer will write code that makes use of multiple cores if the task they are writing can benefit from it. But not all calculations can be split up into simultaneous tasks. Some tasks, like our cake, cannot be divided into simultaneous operations to take advantage of multicore systems.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
[Comics] How did the Wayne Family become so rich?

Ever since Batmans inception his parents and before and even ancestors were also rich and powerful. How did they do it? Politics? Amoral business interests hidden in legit businesses?

[Assistant]
Going back to even before England colonized the Americas, Bruce Wayne can trace his ancestry to the medieval era, where his ancestor was one of the knight of the round table who protected the Holy Grail, and subsequently was a lord of King Arthur's kingdom.

A Wayne arrived in America early during England's colonization and help established the foundations for Gotham City with a trade company which became the basis for Wayne Enterprises. Throughout the decades, the Waynes helped maintain and build up the family business as well as Gotham City, intertwining the success of the city with their own, and appointing themselves as the city's defacto primary protectors and benefactors.

Generally speaking, the Wayne family is characterized as being morally righteous for the most part, facilitating things like the American Revolution, abolitionism, America's participation in both World Wars, keeping Gotham's long-running crime problem in check, and the creation of various public institutions and social programs that kept the city afloat for 3 centuries.

However, they had a notable evil member in an 18th century ancestor named Thomas who ran a devil worshipping cult alongside influential Americans like Thomas Jefferson, summoned and interred a bat-demon within the city that cursed it for another 2 centuries, and lived long enough to become an actual adversary to Bruce Wayne's Batman.

There are also some more grey area ancestors, like Solomon Wayne, who was a extremely religious judge that had an old testament outlook on law and order.

And in some non-comics iterations, the Thomas Wayne that was Bruce's father, may have intentionally or unintentionally gotten mixed up in some shady crime stuff himself which enabled the existence of the villains his son has to deal with in the present.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
Scientists: What is the most interesting unanswered question in your field?

And what are its implications? What makes it difficult to answer? What makes it interesting? Tell us a little bit about it.

[Assistant]
What the *holy hell* is dark energy?

We know the universe is expanding. We know if it didn't, it wouldn't exist. We know *how* it's expanding, and we know that the expansion is isotropic. We know how to model it mathematically to a degree of precision so exact we can practically call it a solved problem.

We haven't the foggiest idea *why.*


[System] Given the following post, respond as if you're commenting on Reddit:

[User] ELI5: How does one "invent new maths"? Like Isaac Newton inventing Calculus, or John Napier logs. How does one answer a mathematical question that's never been answered?

[Assistant]
It's about seeing things in a different way (and studying math of course). You want to solve a problem, or even just see things in a different way... so you define new things and apply them (as long as they are consistent with known math) to see if something interesting pops out.

For example, Newton was trying to describe the speed of a falling object. Since gravity changes the speed of falling object, he *defined* the mathematical concept of "rate of change" (derivative) of a function. He also found out that you can *apply* this concept also if you want to compute the area under a curve.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
Is the possible number of combinations for a 5-digit number(each able to contain 0-9) 99999?

Sorry for the simple question. But if we have a 5-digit number and each digit can hold a value from 0-9. Then how many possible combinations are there? Also, what formula can you use to get this in other situations of different digits. (If any at all).

[Assistant]
In general, in base b, there would be b^n possible combinations of n digits. For your question, you can substitute b = 10 and n = 5 to get 100000. You might have accidentally excluded the combination 00000 when you came up with 99999 as the number of combinations.

However, this includes combinations that start with 0 (e.g. 00135), which are not normally considered to be five-digit numbers. If you want to exclude those (and assuming n > 1), then you subtract away all the combinations starting with 0, of which there are b^(n1), to get b^(n)b^(n1) = (b1)b^(n1) as the final answer.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
ELI5 Pounds per square inch

If I have something that is can take 130 pounds per square inch does that mean that it takes that much weight it can hold  before it breaks? So if something is spread over 4 inches does that mean it can hold up 520 pounds?

[Assistant] Yes, more or less.  That is how pressure works.  The amount of force spread over a surface of contact.  It's why using the same amount of force will distribute force and sting less than if you did the same thing, but with a finger.. or a balled up fist.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
(eli5) Why do some of the worlds largest Oil producers (Exxon, Shell, BP) have such a low stock price compared to Big Tech (Amazon, Google, Apple) despite having similar or better revenue?

Pretty much just this question. Why does Shell have a low stock price compared to Apple despite having more revenue?

[Assistant]
Stock price isn't an indication of a company's worth. Market cap is. Market cap is Outstanding Shares multiplied by stock price.

A company that has 100 outstanding shares valued at $1 each, has a market cap of $100.

A company who has a stock price of $100 per share, but only has 1 share outstanding has a market cap of $100.

In this scenario, both companies are valued the same, despite the disparity in stock price.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] ELI5: Why didn't America stick with the Westminster model when choosing how to run a government?

[Assistant]
Because each State in the Union was a sovereign entity that chose to create a federation to increase total military strength and trade negotiation power with other nations. They only gave up a part of their sovereignty to this federal government.

In the Westminster model Power starts at the top "national level" and is then rationed out at different rates to the units making up that nation. It means that the member countries/entities of the union are not sovereign because the power does not start with them, it is granted to them.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
[DC] If The Flash it a trip wire would he trip over it or would it cut through him?

If I'm running through the woods and I run into some wire someone has placed between two trees I'll trip over it.  Depending on how fast I'm going I might even get a deep cut.  If the same thing happened to The Flash would his speed cause the wire to just slice through his leg or would he just trip as well?

[Assistant]
The speed force protects him while he is running, so he'd likely just trip. Assuming the wire is strong enough and whatever other nonsense has to happen for it to go down how you are describing it.

He has tripped over rocks and cracks and those didn't take his foot off.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] CMV: Soldiers fighting in wars that aren't in direct response to an attack on their country aren't "defending my freedom"

[Assistant]
The majority of what the modern military does it not really warfighting.

Would you say that naval personnel that patrol shipping lanes in order to enable global trade are thereby "defending your freedom" to buy things from other countries and generally enjoy the benefits of globalization?

People tend to have a very strict definition of the "freedom" that the military defends. In modern times, it is much less about your freedom to not be killed/looted/raped by belligerent nations, and more about your freedom to enjoy a modern quality of life via freedom of movement and economic opportunity.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
[Fallout] Why are computers so primitive?

We have nuclear fusion powered cars, advanced energy manipulation, highly advanced cybernetics, etc. Yet all the computers are still big clunky machines with tube screens and shitty interfaces. What's up with that?

[Assistant] Fallout is not set in the same universe as ours.  Aliens have been observing Earth since at least the 1600s, which caused a ripple effect that resulted in the transistor never being invented, among other things (First man in space was 'Merican!). Instead of spending time developing clunky and slow computers, efforts were instead invested in developing the fields of robotics and atomics.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] [Elder Scrolls] I heard that during the Third Era, people were forced to constantly repair their equipment, possibly even during the heat of battle. What advancements happened between then and now where I never have to repair my equipment after I first craft it?

[Assistant]
Metallurgy has advanced a fair bit since the third era. The big break through happened not long after the oblivion crisis when scholars translated a recently discovered Dwemer manual on smithing and rediscovered the lost art of crucible steel. Previously steel was produced from a bloomery and had a high concentration of impurities. This made steel brittle and also expensive. During the war against the Elves, crucible steel became more and more common in the empire as smiths from all over cyrodil and skyrim were contracted to provide weapons and armor for the Legions. Crucible steel has many advantages over bloom steel due to its purer nature such as greater strength and toughness, more flexibility and better edge holding qualities.

The better weapons and armor helped reduce the strain on legion blacksmiths who before spent most of their time repairing weapons and armor. It also allowed a much higher overall combat capability in the Legions since fewer units were waiting on repaired or replacement equipment. It was one of the major factors that helped with the empire's victories late in the war that prevented an overall victory by the Aldmeri dominion.

An interesting side note is that the Aldmeri forces had a hard time accepting the new weapons. For quite awhile they were convinced that they were the result of mass enchantments (impossible given the cost and scale required) or a pact with one of the Deadra (unlikely due to the imperial's worship of Talos and their new found animosity for the Deadra). Their opinion of human craftsmanship was so low that they refused to accept they could make equipment of such quality.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] Do babies know theyre learning/developing skills? Do they realize they werent able to do X before and now they can?

[Assistant]
Infants don't "know" things in the *same* sense that adults do, but they certainly are driven to try new age-appropriate things, and are happy when they succeed at them, in each successive stage.

Episodic memory doesn't tend to appear until roughly (and controversially) around age 3, yet it is an important foundation of what we mean when we say adults "know" things as opposed to simply being able to perform skills unconsciously.

At a certain age young children develop a "theory of mind", where they become able to be self-reflective, and shortly to model the minds of others (like realizing that other people out of sight don't know the same thing that the child just saw).

After that point they are getting closer to what you mean by "know" in the adult sense, but obviously various kinds of development continue.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
ELI5: Why does putting a slice of bread in a jar of stale cookies work?

Baked some cookies this weekend. I went to get one a few hours ago and they were hard as rocks. I stuck the end piece of a loaf of bread in the jar, and now I'm enjoying a soft, chewy, and delicious cookie as I post this. As far back as I can remember, I've always known that trick works pretty consistently. I just don't really understand why...

[Assistant]
In a word, humidity.

The bread's got a relatively high moisture content, and its porous texture gives a big surface area for exposure to air. Because of that, the water in the bread can evaporate pretty quickly until it's at equilibrium with the atmospheric humidity in the jar. And the cookies, in turn, are now less humid than the air... so that moisture content will be condensing on/in them faster than it's evaporating.

Basically, in a sealed environment like a jar, moisture will tend to find its way around until everything is about as humid as everything else.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] [The Goonies] How the hell did nobody find One-Eyed Willy's treasure when the path to it is seemingly integrated with modern plumbing and architecture?

[Assistant] There's a fringe theory that the wealthy country club owners of Astoria knew of the treasure's existence but didn't dare brave the many perils of Willy's obstacle course, so they did their best to keep it hushed up Scooby Doo style.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] Could we terraform the moon?

[Assistant]
The biggest problem with trying to terraform the moon is that it's just too small to hold onto an atmosphere. Were we to somehow manufacture an Earth like atmosphere on the Moon, the majority of it would escape into space almost immediately (not enough gravity). What little remained would be too thin to breath, or even for a human to survive without a space suit (imagine being on the summit of Everest, but much worse). And what little trace of atmosphere was left would slowly be worn away by the constant solar radiation, which, over time would strip the remaining gasses away to practically nothing.

There is however one possible option that might make the Moon 'kinda' habitable, or at least slightly more survivable.

If we were somehow able to manufacture a massive amount of the Nobel Gas Xenon (using perhaps some kind of breeder reactor) we might be able to produce an atmosphere on the Moon that was something close to half normal atmospheric pressure. Xenon is a very heavy gas, and solar radiation lacks the energy to strip Xenon from the Moons atmosphere at this distance from the Sun.

Of course, you could never produce any large bodies of liquid water. Any disassociated hydrogen atoms would float to the top of the atmosphere, and without a magnetic field to block the solar wind, they would be stripped from the atmosphere. All the water would disappear over the course of perhaps a million years. The remaining oxygen would react with the lunar soil...

.... So you'd end up with a large barren desert, with an un-breathable atmosphere. But at least it would be non toxic, and somewhat shielded from radiation by the Xenon atmosphere, so you'd be able to walk around outside wearing a T-shirt, jeans and a scuba tank.

The other advantage would be that if you had a dome filled with breathable atmosphere at say 0.5 bar, and an Xenon atmosphere outside, also at 0.5 bar, if you got a leak in your dome it would be no big deal, no sudden depressurization, you just stick a bit of tape on it and it's fixed.

It's hard to be sure how long it would take to produce a Xenon atmosphere, but assuming you were using large numbers of breeder reactors, perhaps using the Moons molten core as a fuel source, I'd guess you could do it in under 10,000 years.

EDIT: Note the problem of escaping hydrogen could be reduced if you could generate an artificial magnetic field. Using superconductors to create massive electromagnets might make lakes and seas possible. Of course, you'd have to mine the Kuiper Belt for comets, to get the water there in the first place. Then again, if you have a breeder reactor than can make Xenon, why not make Hydrogen and Oxygen while you're at it.

The other option would be to heat up the core of the Moon and somehow make the entire Moon start spinning. This would of course cause massive Moonquakes and require many times more energy that the entire human race has ever expended. The danger being that it could interfere with Earths magnetic field and possibly could result in the Earth becoming uninhabitable.

EDIT2: Correction, Xenon (atomic weight 131)  not Argon (atomic weight 40).


[System] Given the following post, respond as if you're commenting on Reddit:

[User] Eli5 Why does water from a hurricane stay present for so long and not just flow back into the ocean?

[Assistant]
it takes time for water to flow, in part because it would flow back through areas that are also flooded, so that water would need to flow back first.

Water flows in fast because hurricane winds are pushing it. It flows back slowly because it flows "downhill", which is very slow indeed if the area is flat.

it also forms puddles and ponds in whatever depressions there are in the ground.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
[Fallout] Who is this Vault-Dweller guy and how does he excel at everything? How is his late wife just as skilled?

Seriously, I was looking for somewhere to stay after my makeshift camp outside Vault 95 got ransacked by Gunners, and I happened upon this place called Sanctuary. The dude running the place hasn't told me his name, but is referred to as the Sole Survivor or the Vault-Dweller. He didn't say much, just ordered me to get to work farming for him and constructed a crude bed for me to sleep in. Some of these other folk here tell me he was a soldier -get this- 200 years ago before the Great War.  He certainly seems capable in fighting off attackers and returning home with scores of battle-won loot.

But that's just it. This dude is a soldier, who I *guess* would have to know some other survival skills beyond fighting. But he knows how to cook omelettes using Wasteland creature ingredients, can modify like every different kind of weapon and armor to surpass some of the best equipment around, and can concoct some of the most potent and complex chems around. Heck I went to bed after a long day of farming, woke up next morning and the guy had fully refurbished the entire settlement with fancy furniture, better housing, street lights, gaming terminals and water filtration systems in addition to a plethora of missile and heavy chain gun turrets. Surely he didn't learn all this in the army? Whenever I bring it up, he mumbles something about perks and refers me to the Vault-Tec SPECIAL guide, this sheet of paper with cartoon pictures all over it. How does this work, or is he really just crazy?

And I've heard his first wife (not the hot journalist, cage fighter or ditzy nurse) used to be a lawyer who is suggested to have been just as potentially capable in the Wasteland as he is. This might be nostalgic misrememberings from a veteran with PTSD, but how in Atom's name would a lawyer be as effective in combat situations and construction? As society back then would adhere to, I imagine she would have some experience cooking various things and some general homecare knowledge. But even then they used to have one of them Mr Handy robots to do most things. So how is she just as capable as a decorated war hero?

What is going on with these two prewar super-people? How are they so skilled at everything from killing monsters to constructing fully functioning murderbots in areas little better than caves with a box of scraps? Are the rumors that they were replaced with super-skilled synths true? What is going on here?

[Assistant] We don't really know for sure what life was like pre-War. Maybe America trained its soldiers to be superheroes, like Grognak the Barbarian with guns. A trader told me that he read an old United States Army Field Manual that said a trained soldier could dig two feet of foxhole every second. Another told me that the Brotherhood of Steel started as a bunch of pre-War soldiers, and they're pretty badass, so it sounds true to me.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] ELI5: when someone has a higher alcohol tolerance than someone else, whats the difference on a molecular level?

[Assistant] There's these tiny little molecules in your body that break alcohol down into not-alcohol (alcohol dehydrogenase). some people have more of these little worker buddies than others. A lot of it is genetic. Old people have less.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
[Star Wars] Who knew about Darth Sidious' plan before it was executed?

Palpatine usually had other senators or his entourage around him. Did any of them have any knowledge of his master plan?

[Assistant]
Maul seems to have known most of it. He knew a war was coming, as when Savage mentions the Clone Wars he isn't surprised or confused. Just disappointed that they started without him. And with his replacement (Dooku) heading the CIS, he definitely knew his former master controlled both sides. Maul also seems to know that the clones are involved somehow in palpatines ultimate plan, but he was unaware of the specifics until order 66 occurs.

Dooku was also aware of the vast majority of the plan, including order 66, as we see in season 6 of The Clone Wars. Also interesting to note is that according to The Revenge of the Sith novelization, Dooku was under the impression that he would serving as a legislative head in the new empire, and Skywalker would take command of the military. Although with the whole "rule of 2" thing he really should have realized that he would be discarded once he had played his part.

Also, Mas Ammeda and Sly Moore were close advisers to Palpatine and knew of his Sith Identity, so they may have had some knowledge of it.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] [StarCraft] How do Protoss reproduce ?

[Assistant]
There is very obviously male and female protoss, so while we don't know a lot about their physiology, we can surmise there is some sort of sex and gestation.

It could be that they're much like dolphins and other aquatic mammals, with retractable genitalia and give live birth. It could also be a spawning sort of situation. Perhaps they lay eggs. Hell, maybe they reproduce psionically.

Point is, the protoss are enigmatic and secretive. We just don't know.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
ELI5: Are there any countries in the world that can realistically invade the US by force?

By air and sea like a full on invasion where we'd be seeing some serious shit. Or even like an event leading up to an invasion like the bombing of a coast or capture of a major port or something like that..  Just wondering if like Russia or China might have the capability to do this. Thanks!

Edit: holy responses! It's cool reading through every response and seeing a different scenarios! Didn't think about the whole housing/financial market collapse or cyberspace attack! Crazy stuff... And no I'm not a terrorist!

[Assistant]
No. The USA shares land borders with two countries, neither of which have military assets comparable to the USA -- the USA spends $682 billion, to Canada's $22 billion and Mexico's $6 billion. The only countries with military expenditures in arguably the same ballpark are Russia and China.

For countries that don't share a border, an invasion would have to come by sea. To project force overseas a nation requires a blue water navy and aircraft carriers. The USA has 10 aircraft carriers (plus 2 in reserve); there are perhaps 10 other countries that have 1-2 carriers each. The difference between an American carrier and a foreign carrier, just in terms of size and displacement to say nothing of armament, personnel, or training, is staggering -- the UK's (a nation known for its navy) last carrier displaced ~20,000 tons, USA's carriers displace over 100,000 tons.

tldr; Russia and China lack a significant blue water navy. They have no way of effectively projecting force into North America.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
why do we as people devote so much time and money into looking like particular aesthetics?

by particular aesthetics i mean alternative subcultures and things outside of the norm. even i myself do this and the other day i was thinking about just how much time i spend searching secondhand shops, watching videos/following people that have the style id like, etc. im an alternative person and i want to look this way purely for myself, but whats the psychology behind that? if anything most people are turned off by most alternative fashion, so why would it be so important to people to look like a particular aesthetic? i hope i explained that well!

[Assistant] I would venture that the pleasure of self-expression that lies outwith societal norms is a motivating factor for many. In some cases perhaps a desire for social cachet or oppositional/rebellious personality traits. All speculation, mind you.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
[Star Wars] Instead of gambling on Anakin winning the podrace, Qui-Gon decides that he'll neither risk Anakin's life, or negotiate with a slave-owner like Watto. How does he free Anakin?

Keep responses accurate to Qui-Gon's character; No responses like "threaten to kill everyone in town" (although killing Watto is fair game).

EDIT: When I said that Qui-Gon wouldn't "negotiate with a slave-owner like Watto", I meant that he would refuse to buy Anakin from Watto, Watto being a slave-owner and all. Should've been more clear on that.

[Assistant] He finds some other way to get the hyperdrive repaired, or charters a different ship, and just takes Anakin with him when he goes.  It's not like Watto keeps that close an eye on the boy.  There will be somebody around with a ship that will either willingly take republic credits or be able to be mind tricked into it.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] What really kills you when you die of thirst or hunger?

[Assistant]
For starvation, you first run out of carbohydrates (sugars) as an energy source, then you run out of lipids (fat) as an energy source, and finally your body starts breaking down proteins for energy. Since proteins are essential to all your cellular function, this means that your body starts breaking down your organs, starting with muscles. As parts of your vital organs are broken down, you die, usually from heart failure.

For dehydration, you end up with an electrolyte imbalance in your blood, which leads to seizures and heart failure.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
[Game of Thrones] Can the now independent North survive as a Kingdom? There army is depleted, (no respawns, lol) i doubt they have enough gold to buy food for the winter and i wonder if their Queen will ever marry after all the trauma she's been through with me, so no heir.

Truthfully, i can't even be sure that Bran would help her forever with food and stuff. I doubt the Kingdoms will hold forever under Bran. Once the nobles get it into their heads that Bran can't leave an heir or will marry their daughters, they'll revolt.

They won't even have to wait long or do anything in his reign. Just long enough for him to get old and fuck off to find a weirwood to attach to and wait for his heir to the power of the Three eyed Raven. Then whoever marshals the largest Army and beats everyone else becomes king's and he sure won't let the North stay independent or just stop giving them food from the Reach. With not enough to feed themselves through Winter, not enough money to buy and feed their Smallfolk forever and the rest of Westeros against them in a war of conquest, they'll fold.

But what do you think?

[Assistant]
The north could survive, though it's mainly because the south is completely fucked now. Elected monarchies are one of the most unstable forms of government in existence. But let's talk specifics.

Dorne is gonna be the first to break away from the 6 kingdoms. The only reason they were even involved before was because of marriage alliances. With elected monarchies, these mean jack shit. Dorne has nothing keeping them politically attached to the other kingdoms. And they cannot be conquered.

The reach is well and truly fucked. Some low born sellsword is now in charge of the richest land in Westeros? Any of the minor houses of the reach are gonna take out bronn at the first opportunity.

The westerlands are now dirt poor since the gold mines are dry. The only reason they continued to hold so much power was because of their control of the throne, which no longer exists.

The riverlands, stormlands, and the vale are more stable, but it's still not good. The stormlands lack an experienced lord, while the vale can just lock themselves up and declare independence at the first sign of trouble.

With all this chaos going on, the iron islands will be tempted to return to the old ways of raiding and pillaging. The entire west coast of Westeros will be under constant threat.

These are all systemic problems that cannot be solved by a psychic tree. Bran might be able to forestall some of them, but after he dies things will come to a head. The north may survive simply because everyone in the south will be too distracted to pay any attention to them. Or maybe not.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
ELI5: How did some otherwise-advanced ancient civilizations, like the Maya, never develop the wheel?

The wheel was known to many/most ancient civilizations, yet some, like the Maya, never developed it.

Why not?

[Assistant] You need to have some reason for inventing it, for the wheel to be a practical solution to transport you need flat open areas that can be turned into a form of road and also preferably need some draft animal like a horse or oxen to pull carts or wagons. Most of the area was unsuitable for wheeled transport and humans carrying packs on their backs were a more efficient method of transport. The other factor is that there was a substantial amount of water transport which is far more efficient than wheeled transport, so you could say the invention of the boat/barge blocked the need for the wheel.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
[Star Wars] What if Luke had gone to the Imperial Academy and never joined the Rebel Alliance?

Having never met Ben Kenobi and flown off to the Death Star with Han Solo, what would the shape of the Galaxy be?

[Assistant]
Well, let's assume that Luke left for the Academy before any of the events in Episode IV take place. By the time the Tantive IV has escaped to Tatooine with the Death Star plans, the Skywalker homestead is home to only two people: Owen and Beru. After an unexpectedly fruitful moisture farming season, Owen's purchase of a few droids meant that Luke was no longer essential for keeping the homestead running, and with the blessing of his aunt and uncle, he left to join the Imperial Academy.

Let's start with the droids. For the beginning of their adventure on Tatooine, little changes. They escape in the pod, and both are eventually captured by the Jawas. Owen, still on the lookout for a decent translator and any other droids that might help out on the farm, purchases the both of them.

R2 coerces another droid owned by the Skywalkers to remove his restraining bolt, and flees into the desert, this time stealing the Skywalkers' family landspeeder in the escape. Without Luke maintaining it, the speeder breaks down early into the trip, but the little astromech droid finds its way to Obi-Wan's hermitage without further trouble. Seeing the importance of R2's mission, he agrees to ferry the droid to Alderaan, though has no plans to acquiesce Leia's request. He is a simple hermit now, not a man of war.

Without the landspeeder to sell, Obi-Wan has nothing but his own meager savings to pay for a flight, and must rely on merely the promises of wealth once the precious cargo is delivered. Han Solo, having spent too many years as a smuggler to accept a job that sounds too easy (and with no up-front pay, to boot) quickly declines Obi-Wan's offer. For a moment, as he walks away to seek a more weak-minded pilot, Obi-Wan feels a strange sense of loss, despite the brazen smuggler's seemingly simple and arrogant demeanor.

When Alderaan is destroyed, Obi-Wan collapses in the cargo hold of the rickety freighter he's "coerced" his way onto. Surrounded by cargo containers filled with the illegal exports of the Hutt lords, and the fate of the galaxy ever more uncertain, Obi-Wan has never felt more alone. Next to him, R2-D2 lets slip a mournful trill, and Obi-Wan agrees: Something far beyond either their control has gone wrong.

Before we go any further, let's consider the life of young Skywalker, new recruit to the Imperial Navy: With his massive Force Potential and previous experience flying on Tatooine, Luke quickly finds his way to the flight academy, and rises through the ranks at record speed. The training is rigorous, and to this date, he is yet to see real combat. While he is boisterous and enthusiastic like his peers, and his scores in the simulators are compared to the likes of Baron Fel, he does not find pleasure in death. Despite a number of runs against live targets, Skywalker consistently failed to make even a single kill.

Upon graduation, he is assigned to Black Squadron, one of the many TIE squadrons stationed on the Death Star. To his superiors, it's a punishment. The might of the Death Star is so apparent that none would be foolish enough to attack it with snubfighters, and there is little glory in patrol runs. To him, it is a relief.

When the alarm klaxons echoed through the halls announcing the escape of a dangerous prisoner, and the description of a strange old man and his rogue droid that assisted in the escape appeared on his datapad, he paid it little heed. When one of his fellow pilots shouted to the others in the barracks that he'd managed to obtain a live feed of the prisoners escaping, he reluctantly takes a look at the screen.

The starship, boxy and ugly, a stark contrast from the pristine hanger it was docked in, filled the screen. According to one of his fellow pilots, the smuggler who flew it in was blasted to bits upon the discovery of enough Ryll spice to make a sarlacc OD.

At the boarding ramp, a beautiful young woman fired wildly towards troopers offscreen. The ship's small blaster array assisted as well, melting the hangar elevator to prevent reinforcements.

When the camera feed switched to Vader, locked in combat with the strange old man, the hooting and hollering turn instantly to gasps of disbelief. Most of the pilots were aware of Vader's reputation, and a few who had passed him in the halls could even attest to the dark aura that followed him like a physical presence, but none believed the rumors that the Dark Lord carried a lightsaber like the Jedi of old, let alone one colored a deep, angry crimson.

Luke does not join them in their cheering. Since the destruction of Alderaan, his apprehension has grown by the day.

The fight has grown more intense. The old man holds his own, but is quickly, clearly faltering under Vader's sheer power.

Amidst the cheers and whoops of his peers, Luke has a strange revelation: He doesn't want the old man to die.

They are standing on opposite sides of the open blast doors. Were they to close, the old man would be safe to escape to the young woman shouting at him from the starship.

He can see it happening in his minds eye: The blast doors slam shut, separating the old man from Vader.

All it would take is someone there to press the button on the console.

He wants *so badly* to be able to press that button, so much that he can almost feel the texture of it under his thumb, and in his mind he *presses*.

And the blast doors slam shut.

The man survives, and escapes to the ugly, boxy starship with the woman. To everyone's surprise, the tractor beams do not immediately stop their escape.

When Black Squadron is sent after them, they are ordered not to make a killing blow. The ship has a tracking device attached, and the location of the hidden Rebel base has priority over the capture of a few escaped fugitives.

That night, Luke falls asleep replaying the sight of the blast doors slamming shut in his head, unable to shake the thought that something far beyond his control has gone wrong.

Meanwhile, Obi-Wan has escaped the Death Star with the young princess in tow. Though this was not the trip to Alderaan he anticipated, none of that matters now. Sensing a trap, he urges Leia not to travel directly to the Rebel base, but she is insistent. The data stored in R2-D2 is far too valuable to risk delaying its delivery.

When they arrive in the Yavin system, there is little time to prepare a plan. The stolen starship's hyperdrive is fast, but nothing compared to the advanced systems in the imperial fleet. They arrive mere hours before the full might of the Empire. With the plans to the Death Star hastily analyzed, a plan is put into place.

The imperial fleets arrive.

The rebel squadrons launch.

The battle of Yavin IV has begun.

In the chaos of the battle, Vader is rushing to scramble a force against the rebel attack that none of his superiors suspected. He is forced to pick the one squadron at the ready: Black Squadron.

The battle rages, and both squadrons suffer heavy losses. Vader's own personal wingmen are killed, forcing them to be replaced by the more elite members of Black Squadron. On any other day it would have been an honor. Today, it was nothing short of terrifying.

The last few fighters in the Alliance fleet are approaching the end of the trench run, but Vader is picking off the remaining rebels with terrifying efficiency as they rush through the Death Star's docking ring. Soon there are only three. Then two. Then finally just one X-wing, its stabilizer shot to hell and back, leaking coolant, and her pilot shouting furiously on open channels.

Luke watches in slow motion as his fighter's display informs him that Vader's fighter has locked on to the final enemy fighter.

In that moment, he knows precisely what he has to do.

As Luke slams his TIE into the side of Vader's craft, Vader feels his son's final thoughts: not of anger, or desperate confusion, but of calm certainty.

As the dark lord's TIE spins wildly away from the Death Star, it's stabilizers and propulsion rendered completely useless by the explosion, he does not shout in fury, nor does he act quickly to return his craft back to a stable vector. Instead, he feels only a strange sense of calm. Were he a wiser man, he might have identified the source of his peace: Pride.

Wedge Antillies makes the final shot that destroys the Death Star, and is hailed as a hero to the Rebellion, but the victory came at an incredible loss: of all the pilots of all the Alliance squadrons sent on their desperate mission, he was the sole survivor.

This day, there is great hope for the Rebellion. Obi-Wan, one of the greatest Jedi generals of the Old Republic and veteran of the Clone Wars, has joined the Alliance. Though reluctant to fight openly, he carries with him more than just his knowledge of the Force and expertise in war. He carries with the legacy of the Jedi, and the secret he's kept for more than 20 years: That a young woman, strong in the Force and a former senator of Alderaan, is much, much more than she seems.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
[ELI5] The situation in Fukushima, nuclear meltdown and radiation.

Just read an article about Fukushima in Japan and the scientists are saying "all of humanity will be threatened for thousands of years if the Fukushima unit 4 pool is not kept cool." What does this mean?

[Assistant]
To understand this you have to understand what is going on in a reactor. So let's start there:

Everything is made up of atoms. An atom has 3 distinct components called protons, neutrons and electrons. The exact combination of these three things determine how an atom behaves and what element it is known as. Some combinations are unstable and will break down into smaller parts and in doing so release energy and the unused parts. This is nuclear fission. The energy released is of various types and some of it is what we feel as heat. We can use this heat to make steam from water and drive turbines which then generate electricity.

This rate of decay is normally fairly slow (for more on this, look up 'half life'), but there is a way in which it speeds up. In some elements (a specific combination of protons, neutrons and electrons remember), the unused parts of a broken down, or decayed, atom trigger other atoms to break down. This is a chain reaction, as one atom sets off another. If uncontrolled, you have a reaction that keeps growing and growing and providing more and more energy, also known as an explosion. If you want to generate power, this is a very bad thing indeed! So what is done is another material is added that will absorb the unwanted parts of the broken down atoms and stop them from triggering another atom to decay, these are the control rods.

This gives us a nuclear fission reaction which we can control and use to generate heat, which creates steam, which creates electricity.

Now the situation at Fukushima:

Fuskushima is a nuclear power station, which means it produces electricity using the method outlined above. In a large earthquake, the reactors of the nuclear power station were shut down by adding more of the control rods to absorb the unwanted parts of the reaction. This stops the chain reaction in part, but not entirely. The system is still very hot and radioactive (the breaking down and releasing of energy is still going on). Radiation being released into the environment is a very bad thing indeed, as it is very destructive and kills lots of things.

The first thing to remember is that the reactor doesn't go from hot to cold in a few hours, it takes much longer than that. Also, it has to be cooled to stop the heat building up and destroying the part that shields the reactor and stops the radiation getting out. So long as this heat is managed, there will be no meltdown. This means that, under current conditions, Fukushima cannot have a meltdown and is pretty much not going to.

The problem with Fukushima is that they are using water to cool the reactor (it's on the sea for a good reason!), but in the process of cooling the reactor the water becomes radioactive. Putting radioactive water back into the sea then affects the marine life and the food web in general. However, the amount of water required to cool the reactor is so much that storing it is proving impossible, not to mention the water flowing through the ground is also turning radioactive. The end result is that radioactive materials are being released into the world, which is a bad thing.

TLDR: Nuclear fission is the breaking down of atoms into smaller atoms, bits of atoms, and energy. This energy is used to heat water to drive steam turbines to make electricity. The bits of atoms collide with other atoms, making them decay and forming a chain reaction. Fukushima is a power station that uses this to generate power, and was damaged in an earthquake. The chain reaction was mainly stopped by using control rods, though the reactor is still very hot. Water is being used to cool the reactor stopping it from melting down, but is being turned radioactive in the process. Other water flowing through the site is also becoming radioactive. This radioactive water is being deliberately and undeliberately released into the sea, where it will cause problems over the years.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
ELI5: Why do different internet browsers perform better or worse than the other, and what makes Internet Explorer apparently terrible?

Edit: *than others, for you grammar people.

[Assistant] Most web content follows a standard set of rules, called web standards to tell the browser what the content is, and how it should look. Every browser runs on a layout engine. These are sets of code that open web addresses, render the contents, allow you to bookmark, etc. Most browsers (Chrome and Safari, that run on the Webkit engine, and Firefox, which runs on the Gecko engine) follow the standards pretty closely and render content the way it was intended. They also use a Javascript engine, which interprets code the web site sends to your browser to run. This uses another set of standards that browsers follow. Internet Explorer, due to Microsoft being a very proprietary company, decided that they would create their own proprietary standards, and web content would need to conform to them to look good in their browser. So for a long time there was a set of rules for good browsers, and a set of rules for IE. So basically everyone hated IE for making them maintain two sets of code. Also, their were looooots of bugs in earlier versions of IE, where, even if you followed the rules, things would be rendered incorrectly, frustrating developers even more.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] ELI5: How do tattoos stay on permanently if the cells in our body are continually replacing each other.

[Assistant]
Cells replace each other one by one. Whenever a cell dies another cell is formed to fill the void left over. So the entire structure of your skin stays largely intact even though the individual cells all gets replaced. The ink that make up the tattoo is firmly lodged between the cells and will therefore not be able to get out past the cells. Even as cells gets replaced they do not leave any gap for the ink to pass though. So the ink stays largely in the same area as all the cells around it gets replaced.

You can sort of compare this to roads in a city. Even though all the buildings gets replaced the roads are left largely in the same place. If you want to move a road you would have to demolish all buildings along the new road all at once which is often not feasable. So a modern road through a city will often follow the exact same path as the old medeval cart path even though all the buildings around the road have been replaced multiple times since.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
what are the most effective methods/techniques/ways to be positive as learned from the field of positive psychology?

what are the most effective methods/techniques/ways to be positive as learned from the field of positive psychology?

[Assistant] It's easiest to be positive when there's a lot to be positive about.  Make your life more fulfilling by engaging in activities that are pleasurable, that give a sense of accomplishment, and/or that are driven by your personal values.  Even when times are tough.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] ELI5: Why it's dangerous for extremely malnourished/starved people to over eat when reintroduced to food?

[Assistant]
Digestion takes a fair bit of energy to do, especially if you havent eaten anything recently (since it needs to restart a bunch of processes, make stomach acid, etc.). You get back more in the long run, obviously, but it takes energy to break everything down so you can use it in the first place.

For a person who is right on the verge of death, that initial amount of energy required can be enough to push them over the edge and send them into shock and death, so you need to be careful when first feeding someone who has been starving.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
[Marvel] Does the general public know who Sam Wilson is? Or Bruce Banner?

Bruce banner is only seen as the hulk in public, and his science work is probably overshadowed by the fact that he's the Hulk (at least in he MCU) and Sam Wilson hasn't done something huge like Steve Rodgers or Tony Stark, the battle of New York kind of overshadows what he did so do they know who he is?

[Assistant]
Bruce Banner was a widely regarded scientist in academic circles, and Sam is known by the Washington DC Veteran's Association and other servicemen/women volunteer organizations in the area.

Plus, the Avengers *do* have fans, and people who dig into whatever they can about them. Sam has fans as the Falcon and people who know him as his civilian identity.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
ELI5: How do bats know which click is theirs when using echo-location?

Watching the caves episode of Planet Earth on Netflix and in the scene about bats there are thousands of them flying about in the cave. I understand how echo location basically works ( I think ), but when the bat sends out its 'click' how does it know the one it hears back is its own and none of the other thousands of clicks?

[Assistant]
Bats change their echo so they know its theirs.

For example some will change the pitch of their echo.

Imagine you are in room of a lot of people and you are trying to talk to someone across the room. You don't get confused as to which voice is taking to you because you focus on the uniqueness of their voice.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] [DC] Joker is holding me and a bunch of others hostage in a bank. I'm extremely close to laughing at his dark jokes. Would this be a good call on guaranteeing my safety or would he kill me anyway?

[Assistant]
It depends how Joker is feeling. If he's in a good mood, you might end up on his crew that way. You can always use that and wait for an escape chance. On the other hand, sometimes he's just looking for something to emphasize his next joke. Be careful what you laugh at and really think about the results of drawing attention to yourself in that moment.

For example, if he has just thrown someone out the window and says "Have a nice flight", it is safe to laugh. The person who was his target is now falling to their death and it'll take him a second to move on from that.

On the other hand, if Joker has just been hit with a batarang and says 'Oh, Batman, you're sharp as ever", it is not safe to laugh. If you do, he will stab you with it and deliver a follow-up one-liner such as, "I've got your point", or "But this is sharper".


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
ELI5:Why do humans have to sleep?

I get the whole "recharging" idea but it isn't like our body is shutting down when we sleep, it is still using our body. So why do we have to sleep?

[Assistant] We don't know for sure! The best answer (ELI5 answer, not technical one) seems to be that it helps us remove some of the garbage that the cells in our brains produce throughout the day, and flush them out of the system. Though sleep certainly allows for a number of useful biological and neurological things to happen beyond that, and it's not entirely clear what the most important benefit of sleep is.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
[Marvel/DC] Would any hero whose identity is public be able to get approved for any life insurance policy?

I was thinking the other day about whether or not there would be any life insurance company in the world who would be willing to insure Tony Stark, given that he publicly and willingly enters into near-death scenarios.

[Assistant]
Why would Tony Stark ever need life insurance? The man owns a billion dollar company, life insurance would be a drop in the bucket for him.

Depends on how high risk their crime fighting is. There are already life insurance plans for doctors, firefighters and people in "high risk occupations" though the very high risk ones like bomb disposal squads are uninsurable. SHIELD would have likely realized this and offered very nice benefits to compensate though vigilante crimefighters in all likelihood fit under the uninsurable category and have no recourse.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] ELI5: What happens in our brain, when we forget what we wanted to do while starting to do the action?

[Assistant]
Our brain reinforces pathways we take more than once.  Often what happens when we forget what we wanted to do while starting to do something is that a more reinforced brain pathway is triggered when we start the action, causing us to forget the rest once it leaves short term memory.

Sort of like the challenge of patting your head while rubbing your stomach.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
I don't like the comment scores being hidden. CMV.

Over the last day, I find the comment scores has changed my Reddit experience for the worse. I'd like my view changed about this change so I can enjoy it and utilize it to it's best ability.

[Assistant]
Hiding comment scores means that you are now freed from the burden of almost unconsciously checking and comparing the numerical value of comments across a thread. The only thing for you to consider when reading comments is the content of the comment itself and your personal opinion of it, which will lead to a more honest and personal reading experience for you overall.

And if you still want to keep yourself from reading posts that have been auto-collapsed due to a large number of downvotes, that function still works and follows the same threshold it did before.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
ELI5: What is happening when you temporarily forget something you 100% know, such as a name?

Then you try painfully hard to remember but you can't. Then later it casually comes up and you naturally know it without hesitation.

[Assistant] Your memory is organized in a way called "associative", which is kind of like looking up things based on "tags" in things like email. But there are so many things with so many different tags that the tags get "weighted" by how many times you have used them before. when you try to remember something that you know you know, but can't quite think of, you have found a tag that takes you to a memory of having known something but the tag from that memory isn't weighted enough to get you to the actual memory you want. In ELI5 terms, you have found the entry in library card catalog that tells you what book you need, but you can't find the book in the stacks.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] [Pacific Rim] Why did they need to build robots? I'm pretty sure that the USS Nimitz could mop the floor with those monsters, and we have ten ships of that class.

[Assistant] Kaiju Blue, the creatures blood,  is highly toxic and if a Kaiju gets shredded by missiles it will be washing up on every corner of the Pacific, causing potentially the greatest eco disaster in recent history. the idea of the Jaeger's and the wall were to find a way to combat the beasts without shedding blood.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] What is the deal with Sriracha sauce? Is it any good? Is the ban for a real reason or is California just being a dick?

[Assistant]
Sriracha is a really good chili sauce but it is not for the weak-tongued. If you can't handle spicy foods, stay away from it. That's not to say it's the spiciest thing in the world, there are plenty of spicier things- habanero hot sauce, capsaicin extract, Thai food (in that order).

As for the "ban," there was a partial shutdown of the factory here in California. Whether or not we're being dicks is up for debate (I mean we're usually dicks so go ahead and make the assumption that we are). But that partial shutdown was for the brand Huy Fong. There are other brands of sriracha. They're just not ubiquitous like Huy Fong. Think of Huy Fong as the Heinz ketchup of sriracha.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] [Marvel] In 616, how special is Tony's tech and armor? Does it separate him from other super geniuses or is it fairly standard now?

[Assistant]
Stark's armor is the top tier of what is possible for multipurpose battle-focused powered suits. The only one that can come close to him on that scale is Doctor Doom. However, his tech level lags heavily behind many other top scientists who focus more on building specific tools for specific purposes. Reed has built multiversal bridges and has spacecraft capable of causal interstellar and transdimensional travel lying around. Pym has built an extradimensional mansion capable of teleporting people to any point on earth. Everyone else from Hank McCoy to Amadeus Cho have consistently shown the ability to come up with advanced one-shot futuristic inventions to solve the problem-of-the-week in a manner which Stark never really has. When he journeys out into interstellar space, his AI and armor gets cracked like an egg before too long - again, in a way the X-men and Fantastic Four, semi-frequent interstellar travelers, seldom face despite similarly relying on technology to, at the least, keep them alive.

What differentiates Stark from the rest is that while the others live in the future, separated from mankind, he creates it. His technology regularly finds its way into the black market and is repurposed and cribbed from by other villains and wannabe heroes. The targeting and flight systems of today's Crimson Dynamos and Ironhearts were his cutting-edge inventions of yesteryear. As a futurist, he is the bridge between what "normal" people are capable of and the fantastical.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
CMV : Western cultures and values are superior

Some cultures are better than other cultures. That being said, I truly believe Western values are much superior than that of the East. The Greeks started democracy, and in the modern day era, the Americans and French spread those democratic ideals all over the world. Moreover, unlike in the certain other parts of the world, we guarantee our women rights. When a woman is raped, she receives justice, not the death penalty. We allow our women to demonstrate, stand up for themselves and do whatever they wish to do. Our gay citizens have the right to marry and adopt, something that no Eastern country (except South Africa; tho South Africa is still a part of "the West") is privileged to have. Gay people are not killed and imprisoned here, unlike the seventy countries where they are. People are allowed to follow whatever religion they want. People are allowed to talk crap about the ones in power without facing repercussions. It is the West that is leading the world - from industrialization to fighting against climate change. Sure, we may have had our problems, from slavery to colonization, but we have moved on from all those things. We have understood our mistakes, and are taking steps to ensure a much brighter future where all our citizens are equal and free.

[Assistant]
So western cultures made "mistakes" like colonization, slavery, couple of world wars. Now they have learned from those mistakes so they are better.

BUT

Cultures who were oppressed by western countries and are just now beginning to stand up on their own, that are beginning to understand their mistakes and rectifying them are worse?

I'd admit you're right if western countries never committed any of those atrocities ever; but they did. Can't just brush that aside.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
[FF7] ELI5 Cloud's true past and why he lied about it

Beat this amazing game for the first time today (I'm a little late, I know). I'm having trouble putting together Cloud's timeline starting from his childhood and growing up in Nibelheim with Tifa to the point where he arrives in Midgar and joins AVALANCHE. I know he lied about alot of things, but why exactly?

[Assistant]
Cloud wasn't lying. His memories were messed up. Here's the order of events as they are explained in *Final Fantasy VII* (more details are given in *Crisis Core*). Note that the rest of this post is full of spoilers, so stop here if you don't want to know them.

Cloud grows up with Tifa in Nibelheim. When he gets old enough, he goes to Midgar with the intention of joining SOLDIER. However, he doesn't make it and ends up becoming a regular guard instead. He accompanies Zack and Sephiroth (both first-class members of SOLDIER) on a mission to Nibelheim, where the Nibelheim Incident occurs. Sephiroth goes crazy and burns down the city, Zack and Sephiroth fight, but it's eventually Cloud who defeats Sephiroth by throwing him into the Lifestream. Both Cloud and Zack are severely injured at this point. Their bodies are found by Hojo.

Hojo spends time experimenting on the two of them with Mako. Eventually, Zack becomes strong enough to break them out of the Mako vats that they're imprisoned in. Being a SOLDIER, Zack had already been exposed to Mako and handled it okay. However, Cloud began suffering from severe Mako poisoning. They hitch a ride back to Midgar, but some Shinra troops catch up to them and kill Zack. Thinking that Cloud is too far gone already, they just leave him to die. Cloud crawls to Zack's body and picks up his Buster Sword.

From this point, the Mako poisoning messes with Cloud's memory, so he believes that he was a first-class member of SOLDIER and was the one who accompanied Sephiroth to Nibelheim instead of Zack. He returns to Midgar and joins AVALANCHE to get revenge on Shinra. This is where the game begins. Cloud's memories don't get sorted out until midway through the game when he falls into the Lifestream and experiences Mako poisoning a second time. Tifa joins him and helps him sort things out.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
Curvilinear coordinates and analytic functions

I have a function F(x,y) expressed in cartesian coordinates, and I make a curvilinear coordinate transformation to express this function in a new coordinate basis (x', y'). Let's call the function in the new coordinates G(x',y'). If F(x,y) is an analytic function, is G(x',y') also an analytic function?

[Assistant]
Yes, as long as the transformation (x,y)->(x',y') is analytic.

A function being real analytic on a real-analytic manifold is an intrinsic property of the function, ie it is coordinate independent. Changing coordinates on a manifold, using appropriate functions, changes nothing about the manifold or the functions on it, aside from how they look.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
[Marvel] Has anyone seen Spider-Man on a bad day?

I'm sure even heroes have good days and bad days. I've always wondered what a bad day for him would be like.

[Assistant]
Spider-Man at least in his early years had almost nothing *but* bad days. He could barely make his rent, worked for a guy who hated his alter-ego and was so down on himself that, even though he had Avenger's-level power, spent most of his time breaking up street-level muggings. Hell, the only reason he's a super-hero to begin with is because he inadvertently caused his Uncle Ben to die and he gets down every year around the anniversary of Gwen's death.

Then there was the time that Black Cat's good luck power inadvertently gave him terminal bad luck. He flipped a coin over 100 times calling heads every time only for it to come up tails.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
How do gusts of wind happen?

As far as I understand it, wind (or storm) happens because of pressure inequalities. As those high-pressure or low-pressure areas don't "suddenly" appear, I would expect the airflow to be more of a constant thing until pressure is equalized. Where do the gusts come from?

[Assistant]
What is a gust front?
A gust front is the leading edge of cool air rushing down and out from a thunderstorm. There are two main reasons why the air flows out of some thunderstorms so rapidly. The primary reason is the presence of relatively dry air in the lower atmosphere. This dry air causes some of the rain falling through it to evaporate, which cools the air. Since cool air sinks (just as warm air rises), this causes a down-rush of air that spreads out at the ground. The edge of this rapidly spreading cool pool of air is the gust front. The second reason is that the falling precipitation produces a drag on the air, forcing it downward. If the wind following the gust front is intense and damaging, the windstorm is known as a downburst.

Gusts(sudden increase in wind speed) and lulls(sudden decrease in wind speed) in air flow are caused by turbulence in the atmosphere.
The atmosphere becomes turbulent when there is mechanical obstruction to the flow of air or when there is marked convection in the atmosphere.

The former is called mechanical turbulence and the latter is called the thermal turbulence.

In mechanical turbulence,rotating parcels of air called eddies are formed in the vicinity of the ground.The eddies are potent agents in vertical mixing of air layers and it is the movement of these eddies which causes the lulls and the gusts in the atmosphere.

In thermal turbulence,air layers when they are subjected to intense solar heating close to the ground ,ascend due to buoyancy and convectional currents are set up.If these currents are sufficiently strong ,turbulent fluctuations are produced which appear as gusts and lulls in the horizontal wind particularly in the afternoons of hot summer days.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] ELI5: When men get kicked in the balls, why does the pain elevate from their crotch to their lower stomach region?

[Assistant] When guys are in early fetal development their testes start off as ovaries. The nerves develop and connect to the spine just below the stomach. Then as the testes descend through the body the nerves extend with them. That's why it feels in the stomach when you get hit in them, its where they connect to the spine.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] What exactly about the Higgs Boson or the Higgs field gives matter mass?

[Assistant]
The Higgs field, because of something called the Higgs mechanism, has by default, in vacuum / zero temperature / however you want to call it, a large nonzero value, called a VEV (vacuum expectation value), constant everywhere in space and time.

Instead, generally fields take a zero value when you take away all energy from them (they have zero VEV).

The Higgs field can oscillate around this VEV (just like normal fields can oscillate around 0). There are 4 modes of oscillation, but 3 cannot really be observed because of reasons we shouldn't go into now, and the 4th is the Higgs boson. The Higgs boson is very massive because it takes a lot of energy to make that mode oscillate. To give a quantum of energy to the Higgs field in that oscillation mode - namely, to create a Higgs boson, you need a lot of energy. So there actually isn't a lot of Higgses around in the Universe and it took the LHC to make a few. So the Higgs boson is **not** important for this.

Now, the fermions of the standard model are coupled to the Higgs field, i.e. they interact with it. Since the Higgs field is written as the VEV + oscillations (Higgs boson), and the second part is nonexistent unless you have the LHC, then the fermions essentially interact with the VEV. The VEV is constant and so this is a constant interaction of these particles with this background, which manifests as a mass.

The fermions all interact with the same VEV but the strength of the interaction is different between them. For example the top quark has the strongest interaction with the Higgs field, and so gets a large mass. The other fermions have progressively weaker and weaker couplings with the Higgs field and so smaller masses.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
Is human morality getting in the way of Natural Selection?

As human beings, we are now conditioned to overlook physical deformities/defects when it comes to finding mates, causing unfavorable species traits to be passed down through reproduction. Is this sentient morality counter-intuitive to species evolution, or is the human species still too young to judge and that the whole thing is still part of the evolutionary process?

[Assistant] Natural selection is non-teleological, which is to say that it ought to be described by its causes, not any ends. Nothing can actually get in its way. Likewise, fitness is merely the quality of being able to survive in one's environment. If one's environment includes humans with morality, then a person being helped to survive thereby is fit.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
CMV: There is no such thing as a "bad" person, all people do what they think is right based on their ideals.

I belive that there are no "bad" people. All people follow a set of rules that they use to decide what is the right thing to do in any situation. Good people do bad things because they justify them or because in their eyes it isnt wrong. I think that this moral way of thinking is an intrinsic part of humanity, all people; even those we would consider evil believe they are in the right. I think that the true root of evil is in misinformation, because people will often accept a convenient lie in order to justify an immoral action.

[Assistant] Even if you say that people can have their own sense of right and wrong, in an internal vacuum, without any social consensus needed, it is still entirely possible that a person can decide *not* to follow their own moral compass.  It is possible for a person to forego even what they personally think is right in favor of what is *easy* or beneficial in some other sense.  We can still judge whether others are sticking to their guns.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
[Star Wars] What new laws did the Empire instate that were different from the Republic era?

After good o'll Palpy took over and became the emperor, what new did laws did he make? The Empire is an absolute monarchy which means that the Emperor's word is law, so what new policies did he implement?

Did he outlaw same sex marriage? (A weird thing to ask but I'm just coming up with potential new ''reforms'')

Did other species lose it's rights and privileges? (As in, unless you're human you won't progress high in the military, stuff like that?)

How were tax regulated?

[Assistant] There was a humanity first laws set up. Repealing the russan reformations permanently. Stripping planets of their own militias and navies. Gradually non human worlds and former cis worlds were stripped of all autonomy and political representation(cis worlds immediately non human ones later). Ended abolition of slavery of non sapient species, and designated many aliens as non sapient such as wookies. Established formally the imperial armed forces as a standing army of the empire. Created regional governors who held massive political power under palpatine to handle local matters rather than rely on senators or palpatine to settle everything. Strict taxes and heavily patrolled trade routes to limit piracy and free enterprise without an imperial mark. And tons of other smaller concerns rolled out over the first few turbulent but relatively peaceful years.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] ELI5: How do bees get back to the hive when it starts pouring rain if they cant fly in the rain, especially when it keeps raining for days and days?

[Assistant]
The truth is that not all bees get back to the hive and when conditions are extremely unfavorable they may even die while not able to return. However, bees are exceedingly good at reading and even predicting the weather. They are so sensitive to weather conditions (air pressure, humidity, etc) that humans can predict very short term weather by observing their behavior.

For example, you're out tending your apiary when a sudden squall hits and you're wondering if you should pack it up for the day and head home. All you have to do is look at the hive entrance and watch the activity. If the bees are going out as much as they are coming in then the weather wont last that long. If you see no activity or only traffic heading into the hive that storm will most likely last a while.

As for bees that get caught in the rain, they'll find shelter that they can hang out in until the weather subsides and will die if they cannot fly back to the hive in time.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
[Guardians of the Galaxy 2] Spoilers: jumps

So, in Guardians of the Galaxy, there are hexagon-shaped teleportation, essentially.  What are they exactly?  Worm holes, an artificial network-type thing?  If it's artificial, why would they put one in a quantum asteroid field?  And what happened to their faces and bodies after so many jumps and why?

[Assistant] They are messing with the laws of physics, doing so too many times will have weird effects on any matter. Organic matter, which is so finely tuned, will experience adverse effects as a result of too many jumps.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
[Resident Evil] Do zombies really make for that good a weapon?

In Resident Evil, Umbrella seems to be marketing Zombies as a weapon of war, because they can wipe out populations without damaging infrastructure.

Fair enough, but zombies cant surrender. Meaning that once an enemy city has fallen to the undead, your soldiers have to go in and clear out every last one, a process that would almost certainly take longer and cost more than rebuilding a bombed out city.

Also, if civilians get bitten and become zombies, they will not discriminate by side. Meaning that you are turning non-combatants into active threats to both you and the enemy.

How is any of this practical?

[Assistant]
The zombies were more like a prototype of their bioweapons research.

Super soldiers like Nemesis and Mr x was what they were actually working towards. Near unstoppable weapons to hunt down whoever you tell it to.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
Will China fail?

According to Why Nations Fail, China appears to have a significant amount of the issues seen in failing nations, albeit does seem to have fairly strong institutions.

So the question is, can China avoid the fate of states with their similarities, by massive state spending on developing an innovative knowledge run state, or is it destined to fail?

Edit: I realise it's a more normative than positive question, but still interested. And not looking for some crappy communist capitalist slap fight either. More interested in extactive vs inclusive societies and how that may manifest in China's future.

[Assistant]
Acemoglus work doesnt describe a binary  there arent just failed or successful states  a countrys institutions can fall on a spectrum of more or less inclusive.

Eg, maybe Sweden or wherever is extremely inclusive, Spain a little less so, Malaysia has serious flaws, and somewhere like Equatorial Guinea is a truly failed state. And each will reach some steady state economically  E. Guinea will have most people dirt poor until it has better institutions, Malaysia will be better off than most places but not truly rich, Spain will be rich but not as rich as it could be with better institutions, and Sweden will be somewhere near the top.

China went from having some of the worst institutions in the world, which caused mass famines, disease, suffering, and cultural destruction, to a place where most people can at least have a shot at an education, a modest wage, and can even maybe start their own business. Accordingly, theyve gone from a dirt poor country to one thats still fairly poor (gdp per capita is in the ballpark of Brazil or Mexico) but not destitute.

Maybe it will get better institutions, maybe worse, but one might expect it to stay about the same. And it could plausibly stay that way for a long time, and be quite stable.

Maybe economic success has some link to stability, but that doesnt mean somewhere economically unsuccessful cant be politically stable for a very long time. Its not a ticking time bomb.

Also, just because of Chinas sheer population, even reaching moderate success economically gives the CCP enough resources to be a superpower.

So, its complicated, but theres no reason to expect an implosion just on economics alone.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
ELI5: Why is it that after getting blood drawn, and the needle gets pulled out of our arm, the hole left in our veins doesn't continuously leak blood into our bodies?

Does it just seal really quickly? Does some blood escape out of our veins and into our bodies?

[Assistant] The blood clots, or becomes hard at the site of an injury with the help of what are called platelets. This creates a temporary seal. Once this is complete, the platelets secrete what is called platelet-derived growth factor. This causes nearly connective tissue to undergo cell division and growth to permanently patch the hole.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
Can people age differently on other planets because of gravity/relativity and come back to earth younger than their siblings?

In some movies, people go to other planets and for numerous reasons, they age differently than people on earth. Some say a few actual hours on these planets can actually be years on earth. I understand the concept that time is calculated differently on other planets but can anyone go to another planet and come back to earth physically younger?

[Assistant]
Yes, but not significantly.

Gravitational time dilation is indeed a *real* effect. It's not caused by timekeeping or convention. Time really does run slower if you're in a strong gravitational field.

*However*, the effect is almost always so small that it's impossible to measure without extremely sensitive equipment. The different in gravity between planets is too small for the age difference to be noticeable.

It only really becomes significant if you're right on top of a black hole. This is a pretty hostile environment, but theoretically you could put a space station there if the black hole is spinning fast enough. It's technically possible for a planet to be there too, but it's probably not very likely. You could hang out on top of a black hole for a while and come home a *lot* younger.

Of course, to get to the black hole and back, you'd probably want to fly in a really fast space-ship, which means you also get time dilation from speed anyway.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
[Hot Fuzz] What happens after?

Following the events of the film, how do Nicholas and Danny go about rebuilding Sanford given the sheer number of incarcerated or killed members of the town, many in important positions?

How does Britain as a whole respond to the existence of a death cult in rural England?

And perhaps most importantly, does Sanford ever win the Village of the Year award?

[Assistant]
The rebuilding process is going to take years; pretty much every local institution save the police has suffered massive hits via murders or arrests. Eventually people will move in to fill the vacuum, though some otherwise imminently qualified candidates will be scared off by Sanford's new reputation as the cult murder capital of rural Britain. The people who first take on those positions may be undesirable in some ways; less experienced/qualified then the people they replace, somehow less employable in nicer areas, and so on. That said, whoever they get likely is going to be at least basically competent.

Sanford is a front-page item for a brief time, but the national news has bigger fish to fry. The Chief Inspector of the London Met and his cronies were trying to be coy at the end, but the situation on the ground in the city must have become absolutely horrible. Considering how brutal they were to Angel when kicking him out, trying to bring him back smacks of a desperation move. And the city was already "crackheads with kalashnikovs" and "stab happy hobo Santa" level bad while Angel was still working the beat.

It will likely be several years before Sanford is a proper VOTY candidate again. Once the town has a chance to find a new status quo, it may have a chance. Spoilers for The World's End below...

>! Worst case scenario, they're probably a lock for VOTY after the societal collapse caused by the withdrawal of the Network. With Inspector Angel at the helm, they probably weather the collapse of technology better than average, especially if the post-NWA house-cleaning reveals more stockpiles like the one at Webley's Farm.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
ELI5: Why do scientists say directions such as left/right and up/down dont exist in outer space?

Lets say you took off in a little rocket ship from Texas, and you saw a cool star behind the earth. Isnt that the direction you would go in? So thats left, right, up and down in space, no?

[Assistant]
Not really. The concept of *behind* still makes sense, in a relative way (i.e. your ship A, earth B and cool star C are all aligned; someone at A could say C is behind B, or someone at C could say A is behind B).

However, once you leave earth's gravity well (or that of another suitably large object), there is no universal up/down/left/right. You could roll your ship 180 degrees while staying on course, and totally invert all those relative directions.