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

[User] ELI5: Why does cost of living increase faster than our wages? And why do we not simply make them proportional?

[Assistant] Because companies are both trying to get you to pay as much as possible for stuff while also trying to keep your wages as low as possible. As both increases their profits. So the money goes to the already rich business owners.


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

[User]
[MCU] How were the remaining Avengers viewed by the public in the five years between Infinity War and Endgame?

It's basically public knowledge that they fought Thanos and admittedly gave their best and suffered heavily but in the end they failed to stop the mad Titan and half the population vanished. Now while I assume that everyone would treat them rather fair in the beginning, history is never nice towards losers. Aren't there people starting to blame them for the snap? Or at least for their failure to prevent it?

I would guess that many people are quite angry and that this anger becomes directed towards the leftover Avengers.

Follow-Up questions: Why were the proud Asgardians okay with a drunkard as their king? Why did the support group we see in the beginning of Endgame accept Steve Rogers who couldn't prevent their loved ones from crumbling to dust?

I'm perfectly aware that the Avengers bear no responsibility for Thanos winning but I'm deliberately sure that there are many angry, wrathful people around who really like to have some scapegoat at hand. Think of people as J Jonah Jameson, he would be the first one to try and blame Spiderman for basically everything. Even if Jameson was snapped away there must be someone around to blame the Avengers.

[Assistant]
It does not appear that the public held the Avengers' loss in the Infinity War against them.  The Avengers let the world know about Thanos, they told the world about the Infinity Stones and the Snap, and the Battle of Wakanda was known around the world.  Multiple government agencies (we at least saw SHIELD detected it) would have detected the disturbance of Thanos' invasion of Wakanda, and Okoye and M'Baku would have given the official Wakandan report of their war against the extraterrestrial invaders in which the Wakandan Military and the Avengers fought.  The world experienced the Chitauri invasion of New York 6 years prior, so they know about ET invasions and the Avengers gained a reputation there.

It also seems that the world was reeling following the Snap, which also would have included the public loss of half the Avengers.  Keep in mind, public reporting during Infinity War included the disappearance of Tony Stark after New York was invaded so they have plenty of evidence that they genuinely did fight.  After the Snap, the Avengers (particularly Natasha Romanoff) became one of the leading agencies dealing with the fallout of the mass death. So yes, some people probably did blame the Avengers but anti-Avenger sentiment was not prominent post-Snap.  Could this have turned at some point? Yeah, but they did the Time Heist and brought everyone back before it did.

Hulk was the main Avenger at this time.  We can see in the (canon) deleted scene from Endgame that he was the only one who was operating as a superhero.  He's gotten over his bad reputation as a monster when he became Professor Hulk, he's a celebrity. The public probably viewed him as one of the only stable things in a world gone mad, a superpowered being who cared about the little guy and saved lives.

For your follow up questions: largely, the Avengers had built up a reputation at this point.  Captain America couldn't stop Thanos, but he can talk to people and help manage their grief.  He's openly a national legend and hero who has saved the world many times before and failed once, now he's helping people in whatever way he can.  Thor is just straight up the rightful king. The Asgardians follow the rightful king.  When Loki disguised himself as Odin, they followed him even as he built massive statues of Loki, ate grapes, and watched plays about how great Loki is all the time.  They follow Thor who they've known as a hero for 1500 years, even though he's had a rough 5 year period following their defeat by Thanos.


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

[User]
What is the understanding of free will in compatibilism?

So from my understanding, to believe in free will (atleast as characterized in the way of libertarian free will, or libertarianism, as seen on the philosophy surveys) necessitates belief in something extra physical that gives an agent power (agency) to actually deliberate a decision themselves rather than simply by determined by their genetic makeup and life experience (like we would say other physical things are). Obviously an example of this would be divine will.

From my understanding of compatibilism, determinism and free will are not mutually exclusive. I have heard often that this is a way to hold onto some moral systems that hinge on an agent actually having agency, rather than a commentary on free will. If this is the case, what is the compatibilists understanding of free will. Is there a secular case for free will?

[Assistant]
The libertarian and the compatibilist both have the same general understanding of free will, viz. that it is the capacity to function as an agent of one's behaviors, through processes like deliberating about what to do, where those deliberations are the significant cause of what one does -- or something like this.

The difference is that incompatibilists (including both libertarians and those who deny we have free will) think that if determinism is true then we cannot have any such capacity, whereas compatibilists think otherwise.


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

[User] ELI5: Why does parallel parking only work when reversing.

[Assistant] Because it's the front tires that turn. So whichever end goes in first, the other end will be oriented wrong so you'll need to turn that end to make the car parallel. Since it's the front tires that turn, you can only turn the front end of the car like that.


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

[User]
Why do bases "eat" flesh?

with acids it is because the released H-atoms react with the proteins and breaks up the pepitde bond. but how do bases work?

[Assistant] Bases do this through saponification.  Saponification is the hydrolosis of the fatty acid esters that make up our cell membranes.  This reaction goes much slower than that of the acid, but when completed, the "flesh" or whatever organ it used to be should be dissolved into the solution.


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

[User] [The Flash] Inspired by the other post here, if Flashs Rogues became aware of his true identity would they respect that boundary and even be protective of other less ethical villains finding it out as well?

[Assistant]
The Rogues definitely wouldn't act with that information. As shown when they didn't do anything back when the Flashes did have public identities.

They also don't condone the involvement of women and children, so if they did catch wind of a more seedy bad guy playing to do something like that they would definitely stop them or at least warn the Flash. They are very harsh against these kinds of people and we can see this when they turn on the second Captain Boomerang who had been feeding innocent people to his father, including women and children.


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

[User]
Cutting my PhD thesis in half

I can't avoid the fact that the last two thirds of my Computer Science PhD thesis is much stronger than my first third.

The first two years of my studies were devoted to following dead end routes and discussing these dead ends forms about 25,000 words of a 75,000 word thesis. In that section there's a lot of explanation that's mostly in service of exposition for the final part, with no real satisfying outcomes.

I have a feeling that in my viva I'm going to be defending those 25,000 words non-stop and I really don't want to do that. Instead I was thinking that I might be able to get away with just not mentioning my early work. All I have to do is re-frame the latter half of the work.

I haven't spoken to my supervisor about this yet as I haven't quite decided how to approach the subject. He did say that my thesis was like a PhD and a half though the other day.

So does anyone on AskAcademia have any advice or experiences they would like to share?

[Assistant] I tried to put this type of material in several appendices so that others could read about the unproductive and half-explored leads, if they wished, without letting this material detract from the main message.


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

[User] ELI5: Why does the acid in coca-cola cause tooth cavities, but the acid in oranges is fine?

[Assistant] It's not fine. Orange juice is just as harmful, if not more, than soft drinks / sodas.  If you eat an Orange however you are getting alot of fibre (the pulp) along with the juice. The chewing produces saliva which will help neutralize the harmful acids in your mouth.


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

[User]
What have phenomenologists had to say about the mind-body problem?

I know there is a sense in which metaphysical questions go beyond the domain of phenomenological investigation, but i'm curious to know if any phenomenologists have, in virtue of their insight gained through phenomenological analysis, made significant contributions to, or provided a new or altered conception of the mind-body problem/the hard problem of consciousness.

There is a lot of talk about whether or not phenomenology can be naturalised as well. I'm wondering, how does a negative response here, namely phenomenology cannot be naturalised, align with considerations of the mind-body problem/the hard problem of consciousness? If phenomenology cannot be naturalised, is that equivalent to denying that we can ever have an answer to the hard problem of consciousness?

[Assistant]
If you take a look at Merleau-Pontys short lecture Man viewed from outside you can see how the Cartesian M-B problem might dissolve when we understand the conceptual origin of the Cartesian mind in a certain way.

The short story is that M-P argues that we should read the Mind (soul) in the *Meditations* as being the product of a reflective abstraction (here we mean the verb abstract in the most literal, etymological sense - to draw away from).  So, "the mind" as such emerges only from this process by which we alienate ourselves from a more ontologically basic (from the point of view of phenomenology) thing - something like an embodied mind.  Really, there is no mind as such, there is only this embodied mind.  The Cartesian mind is an important practical and theoretical concept, but it is not really the thing we have.

By way of a maybe lame analogy that maybe only works for me - there is a line in Aristotle wherein he describes the body of a dead person as "a body in name only."  That is, it's not *really* a body - a body is the up and moving around thing that we have.  This pure mind that Descartes asks us to imagine through skeptical analysis ends up being something like this - a mind in name only.  An actual mind is this embodied, sensual, intentional thing that phenomenology is concerned with.


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

[User]
Are there: Evolutionary benefits to blood types?

Hello,

I understand blood types are pretty incredible and varied, but are there any evolutionary benefit for these blood types?

Furthermore, as a follow-up question, are there animals who only have a single blood type (excluding Rh +/- factors?)

[Assistant]
Pathogens like bacteria or viruses can carry antigens (chemical signatures, like blood type) from other hosts. Current idea is that, if those pathogens are equipped with their former host's type B, say, then since you're type A, your immune system has a much easier time recognizing the pathogen as an invader--they're very different, after all--and can respond to it more quickly and effectively.

It's just a means by which different immune systems can respond better to invaders.


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

[User]
[Terminator Salvation] Why did the motorcycles the Terminators rode have human usable controls?

Couldn't the Terminator directly interface with the motorcycle to control it, both being more efficient and preventing humans from using it? Also why did the motorcycle even need a driver instead of just putting an artificial intelligence in the motorcycle?

[Assistant]
One thing to remember is Skynet, for all of its brilliance, isn't human.  Doesn't think like a human.  Doesn't behave like a human.

Seriously, Skynet set in infiltration robots with rubber skin and figured that would work because earlier infiltrators without human skin were total failures.  The rubber skinned ones were failures too, so then Skynet developed organic skin and even it wasn't perfect but at least was more successful.

That's kind of the way it operates.  Skynet will do the bare minimum that it thinks will work, and then when it fails Skynet figures out what it did wrong and then upgrades it.

So to the motorcycle.  Skynet found a working Motorcycle and figured out how to apply an AI to it for scouting.  Some were lost, but overall the numbers were good so it keeps buidling more.  Eventually the humans figure out how to hack the devices, so they can ride them.  Skynet does a minimal redesign so that the manual controls, which were still there, are removed.  Problem is that it didn't change anything else, so if you can hack it a human can still just weld on controls.  If Skynet thinks this is still a problem, Skynet will evolve the machine so that you can't put on any human controls.

In short, Skynet is an evolutionary REACTIVE system.  Its programming will not allow it to make the quantitively leaps that humans do or even think that far ahead like that.  Meanwhile, it brilliantly predicted how human warfighting would progress and acted accordingly.


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

[User]
[Halo] Will transhumanism ever be possible, what are the pros and cons of it?

Will transhumanism ever be possible, and what are the pros and cons of it?

[Assistant]
Ever? Yes.

Pros: we become more than we are, which is good.

Cons: we're gonna have to abandon certain things that makes us "us" in the process and this is going to be both painful and potentially dangerous.


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

[User]
[Lord Of The Rings] Did Gandalf really need to hold the Balrog at the bridge?

The bridge seemed quite narrow and it looks like by the time the Balrog crossed it the fellowship would have escaped. If Gandalf didn't hold the Balrog there, would it have really continued chasing them all the way out of the mountain?

How far would it have chased them?

[Assistant]
I think they fought for a week non stop? So the Balrog eventually wouldve caught the fellowship when they got tired. If Gandalf wouldve made his stand there he wouldve revealed himself too soon and the scale of the fight might well have hurt or killed some of the fellowship.

If Gandalf expected a better battleground he might have waited but as it was he couldnt risk it.


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

[User]
[Marvel] What is physically stopping anyone from defeating Squirrel Girl?

Supposedly she's unbeatable, but allegedly her only power is Animal Communication that only works on a single species. So... why can't Thor drop an asteroid on her head from orbit? Why can't Sentry speedblitz her? I think I heard somewhere that Iron Man has a thermodynamics-violating beam that somehow hits HARDER the further it travels, so why can't he just fly a few clicks into the air and shoot that thing at her? Even Doctor Doom, the guy that supposedly (my knowledge of comics is pretty limited, so this might be wrong) fought Celestials for *28* minutes, seemed unwilling to use all of his magic and tech to kill her and her squirrels instantly. What's going on here?

[Assistant] Squirrel Girl's superpower is animal communication, but the best and most used tool in her tool bag is conflict management and de-escalation. Its not that these people can't defeat her, she's just really good at talking people down. She's one hell of a communicator.


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

[User] ELI5: A bag of chips has air in it to prevent the product from damage, but when I leave a bag open, the chips go stale. What is different about the air?

[Assistant] Nitrogen is used in chip bags because nitrogen is an inert gas. Meaning that it is not chemically reactive. Therefore, the nitrogen wont affect the quality of the chip. Once you open the bag, you then release the nitrogen and expose the chips to the air, which has moisture in it. The chips themselves are very dry because they've been fried and salted, etc. The chips will then soak up the moisture from the air and lose their crispness and become stale. The gas is also used to 'plump up' the bag so it will apear larger, but mainly used to keep the chips fresh.


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

[User]
ELI5: Why are recycling places such sticklers about items being washed out?

If a bottle or can has a label glued to it or paint on it, how is that so different from a bit of food?

[Assistant] Rats and other vermin are hard to deal with.  Dump a bunch of oily, dirty old food tins and soda bottles with sugary residue into a big pile, you're getting mice, rats, and vermin of all sorts.  They'll travel with the cans and bottles down the sorting lines, into the shredders, etc., messing up the equipment and the workers.  Labels and paint can be removed by passing the shredded materials through a chemical bath or sprayer.  Food particles have to be washed out (along with the vermin).


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

[User]
ELI5: Why are avocados so expensive at fast food places?

I live in Southern California and there are tons of avocado groves all over the area yet almost every fast food place I go to (Subway, Chipotle, etc.) charge an extra $1.50 just to add a couple slices of avocado. Is it because they know people want it, they go bad more quickly, they're just greedy..?

[Assistant]
Because they are expensive to grow, and all food will be more expensive at restaurants than at the grocery store.

Avocados are also not a default item. They are not liked by everyone and they spoil very quickly so they charge more to cut their losses to spoilage.

Those that like them are willing to pay extra for the luxury addon.


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

[User] [Harry Potter] Who is the strongest witch or wizard to ever go to Hogwarts? Not most accomplished or famous, just has the greatest mastery of magic.

[Assistant]
The strongest Hogwarts grad that we see in the series is Albus Dumbledore. In second place is Tom Riddle/Lord Voldemort.

Characters whose power levels we dont actually see but were likely very high are the original founders and Merlin.


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

[User] ELI5: When you take cookies out of the oven they are so soft that if you move them too quickly theyll fall apart. If you wait a couple minutes, theyre much more stable. Whats happening in that two minutes?

[Assistant] Butter/fat cools and hardens. Bonds between starches and proteins (from the flour and egg) are more mobile with more heat. Steam is released as the cookie cools so there is less moisture content. Chocolate chunks also resolidify. Basically, the cookie becomes more viscous/solid in the way that everything else becomes more viscous/solid as it cools.


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

[User] ELI5: All these articles talk about the housing shortages and rising rents. Explain to me where all these people lived before! No article reports on this side and Im confused.

[Assistant]
Typically you have people at various points in their housing lifecycle. Young people renting apartments, then buying condos or starter homes, having kids and upgrading to a family home, then downsizing to a retirement home when the kids move out and they get older, then perhaps into an assisted living or nursing home.

COVID threw those progressions off  old people stayed out due to outbreaks in assisted living facilities; empty nesters didnt want strangers in their homes or want to travel to shop for retirement homes in Florida and Arizona. And perhaps their single adult children decided to move home rather than be stuck alone in an expensive apartment in a shut down city.

But at the other end you had various people wanting to move up to the next housing stage because they wanted more space. So people who might have planned to buy a house in a year or two jumped into the hunt for a starter house or their upgrade to a bigger house when parents were working from home and kids were remote learning. So something like 3x as many people wanting to buy as usual, but half as many looking to sell as usual created a bottleneck in the housing market. If seniors dont downsize, then people in starter homes cant step up, and that means nonstarter homes for those wanting to buy their first homes.

Apartments are going up for a few reasons. One, people are returning to cities as vaccines are available and city life is more available. The rent deals to be had when people chose not to renew and moved back home with mom & dad in the suburbs last year are gone. And inflation means higher costs to maintain and keep up apartments, higher utility bills, causing landlord to raise rents to reflect cost increases.

And both home sales and rental apartments were affected by COVID causing delays in building, as things like permits and inspections took longer, building material shortages and skyrocketing prices, labor shortages all meant fewer new housing until being built to replenish obsolete ones, growing population of adults, etc.


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

[User] How does cancer actually kill you?

[Assistant] There's some variation between different types of cancers, but we can think of their effects at the tissue level, organ level, and systemic level.  At the tissue level, cancers can be locally invasive, with upregulation of various factors that allow it to penetrate through tissue planes and break down normal connective tissue barriers.  In doing so, a cancer might eat through a part of the GI tract leading to a perforation and sepsis, or invade into a major blood vessel and cause severe bleeding.  Cancers can also cause a mass effect just by the size of the tumor impinging on neighboring structures.  This may cause occlusions of vital passageways (commonly seen in the GI/hepatobiliary tracts), or increase pressure on sensitive areas such as the brain.  At the organ level, cancers that grow in vital organs can severely disrupt their function.  A cancer of the liver may severely impair the synthetic and metabolic function of the liver, leading to coagulopathies and encephalopathy.  A tumor in the lung can physically and mechanically prevent it from functioning as a gas exchange interface.  A cancer in the bone marrow can reduce the body's ability to make red blood cells, white blood cells, and platelets.  Note that both tissue level and organ level dysfunction may be at the site of the primary tumor or at a metastatic location.  At the systemic level, many cancers can cause disease through their paraneoplastic effects.  Many cancers have profound effects on the hormonal and endocrine milieu of the body and can lead to severe derangements in electrolyte levels, neurotransmitter signalling, etc.  Also remember that a malignancy represents a state of high stress for the body, which can tax its ability to deal with other comorbidities.  In addition, infections are a common problem for these patients because the immune system is often impacted, either directly or secondarily through chemo.  Along this vein, the treatments we have for cancer are rarely benign, and may include invasive surgeries, high doses of radiation, and what are in effect therapeutic poisons.


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

[User]
ELI5: Do our bodies get used to certain exercises, and so start burning fewer calories when we do them?

My instructor at the gym says that I need to keep changing my routine, as my body will plateau and burn fewer calories even doing the same work.

Why is this? Surely lifting a certain weight a certain number of times will always require the same amount of energy?

Or is my body just getting more efficient at it?

[Assistant]
Your body will realign and reallocate muscle fibers as you tear them and they get repaired. So, technically, yes - you will get better at doing one particular motion efficiently at one particular weight and rep range. In reality, though, you will likely up the weight as you build muscle and get better at the exercise, and so will end up burning MORE calories moving a higher weight and doing the same exercise.

Lift heavy, lift compound.


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

[User]
ELI5: What is Markov Chain and why is it important?

Explain like I'm Five. Maybe seventeen.

[Assistant]
A markov chain is a mathematical approach to disentangling several possible events that depend on outcomes before it.

To stay topical, take a look at March madness brackets. You have a pretty low chance of getting your bracket right. But if we apply some really simple logic, we can increase that chance.

If you fill out the bracket as a set of unorganized fill in the blank boxes, you won't do well. For instance, you could have a team that you eliminated in the sweet sixteen winning the final four. That doesn't make sense. Instead, let's create a chain of causes that predict the inputs into the next block of causes.

If a team doesn't make the first round, they can't end up in the later rounds. Better right?

But if we have even more information, we can do even better. We could fill out our bracket *as* the tournament is happening and expect to do really well. A player who lead scoring got injured in the elite 8? We can use that information to reduce the team's chances in the final four. That's why a Markov chain is so.good at making predictions. It refined it's approach as it gets information.

In real use, Markov chains get much more sophisticated. So sophisticated that becomes hard to keep track of all the variables. That's where higher level math like *linear algebra* comes in.

In a *Hidden Markov Model*, you don't actually have to know how all the pieces fit together. You just need some good relationships:
- taller players do better
- players have to be healthy to play
- scoring early is important

Using *eignevectors* a mathematical approach can take a *system of related linear equations* and figure out which variables are *independent* of the rest. You do this by mathematically rearranging all the equations so that the few that dominate the rest fall out.

- taller players do better and the early scoring for this team is directly caused by their best player being tall. It's really only one variable at work here.

As the Markov chain gets updated, the most important variables might shift.

- Taller players do better but this team's tall player is injured so the height variable is no longer part of what contributes to their early scoring.


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

[User] [Black Panther] Has there ever been any rebellions against the reigning monarch? Any revolutions at all about how the system of government is set up?

[Assistant]
Yes its happened at least once in the past because human nature and all that, but no its not frequent by any stretch of the imagination. Once the Wakandan tribes forged the kingdom and began focusing on exploiting their Vibranium deposits there was a surge in quality of life for the Wakandan people.

When other nations were breaking their backs tilling the soil by hand, Wakandans were using rudimentary vibranium tools.

When other nations were fighting gruesome wars of attrition, Wakandans were hiding and advancing their technology for their people.

When other nations were discovering microprocessors, Wakandans were perfecting their nanotechnology.

Wakanda was leaps and bound beyond the quality of life of every other nation on earth. The Wakandan people had a vested interest in keeping the peace domestically not only because they were afraid to cause waves that might make other nations notice them, but also because why fight a civil war when you know your day to day life is relatively easy compared to everyone else in the world.


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

[User] ELI5: Why is it considered bad to treat animals intended for consumption with antibiotics? Can it cause health problems in humans or is it mainly a sustainability issue?

[Assistant] They aren't fed antibiotics to cure diseases they have. They are fed low doses of antibiotics throughout their lives which accelerates their weight gain. The antibiotics end up in their waste and in the environment, and any bacteria in or on them may develop resistance to the antibiotics.


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

[User]
ELI5:The Cheerios Effect

As I poured my morning box of honey nut Cheerios, I read the back of the box. It explains, that if you put two honey nut Cheerios in a bowl of milk, they will eventually gravitate towards each other and stay together. I tested this out and it works! Why do my honey nut Cheerios gravitate towards each other and then stay together?

[Assistant] It's because they're both held up by surface tension, which pushes the milk down ever so slightly. Think of a flat piece of plastic with water droplets on it. Wherever you push down, the water droplets will converge there. Both cheerios are pushing, so each will be drawn to the other. Once connected, they have made themselves an even bigger bowl and will stay together in there until you eat them.


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

[User] [interstellar] why didn't they just go to Mars?

[Assistant]
Because Mars has **nothing**. No oxygen - no atmosphere to speak of, no carbohydrates, no liquid water, no Earth-equivalent gravity to keep our bones and muscles strong, no magnetic field to protect from cosmic rays, no molten core for warmth and geothermal energy. Let's not forget the planet-wide dust storms, made of superfine, abrasive dust, which can go on for months.

It would cost a tremendous amount of money to set up a viable colony there, orders of magnitude more than it would cost to send one single colony ship through the wormhole, in search of Earth-like planets.

Besides, if they wanted to put humanity under a dome, they could have just built one here on Earth.


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

[User] Why does time (seem?) to speed up when we are happy?

[Assistant]
Einstein's relativity theory. He explains it as such

>When a man sits with a pretty girl for an hour, it seems like a minute. But let him sit on a hot stove for a minute and it's longer than any hour. That's relativity.

Relativity says that as an object goes faster, the more globally bent timespace is round it, which means, clocks go slower.  Now you may wonder what this has to do with you...well, you're a clock. When our processes go slower, time seem to go faster for us.

Basically, what you're experiencing is a taste of nonexistence. And it taste good.

Or, it could be as simple as you enjoy the subject at hand so you're not worried about what time it is, whilst when you're doing something boring part of you is wondering how long it will take.


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

[User]
Have photons a mass?

One time in Biology class my teacher asked what light is. I said it can be described as a particle without mass (a photon), or a wave. He then said that i am wrong and a photon has mass.

I researched alot...

I come to the conclusion that a Photon has no mass. My "Evidence" was:

E=(mc) + (pc)          because m(restmass) = 0

its E=(pc) or E= pc

because E=gamma*m*c and p = gamma*m*v its:

v=c      so if m hits 0 v becomes c. a photon defines the speed of light...

My teacher then said following:

1. A Photon has to own a mass because its influenced by gravity.
2. A Photon has mass because it has momentum (p=mv)
3. A Photon has mass on its flight but not when it hits something.. the mass (magicaly) dissapears as soon as it hits an object...
My Questions to you poeple are:

1. Can i Use p=mv on a Photon or do i Use p=E/c? and why?
2. Are Photons influenced by gravity because of their mass or because of the bended space?
3. Can a Photon bend space? (does mass bend space or does Energy bend it?)
4. Is it possible for a Photon to own a mass on its flight? (and only on that.)
5. and how is it able to move with the speed of light when it owns a mass?

If something isn't clear (wouldn't suprise me^^) i'll try to circumscribe it...

I hope you guys can help me :)

[Assistant]
As far as we know, photons are massless. If they do have a mass it must be less than 10^-54 kg, less than a trillionth that of an electron. Most of the misconceptions your teacher has comes from various inappropriate versions of energy, mass, and momentum.

1. This isn't the case, gravity affects the paths things travel on, including the paths of light.

2. p=mv is just an approximation for slow massive things.

3. This doesn't make sense.

4. You should use p=E/c=hf/c where h is Planck's constant and f is the frequency.

5. The latter.

6. Yes it can, but we'll probably never detect this.

7. Generally no. You could probably construct a system (like a crystal that behaves differently as light goes through it) where there is an "effective mass" but it wouldn't be the same as a photon having mass.

8. It doesn't.


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

[User]
[Marvel] Do other world leaders respect Doctor Doom?

What do other world leaders think of him? Do people like Putin and Trump and so on say to themselves or in speeches "Doom's an example of a strong leader, and that's how I should be"?

[Assistant] Even if most nations don't agree with Doom's philosophy of utopia through his unquestioned rule, they'll certainly respect his power in the sense of knowing it's not worth it to pick a fight with Latveria.


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

[User]
ELI5: Why can't we determine the position and momentum of an electron with ~100% accuracy by controlling both of those factors?

For example, can't we beam nearly-equal-strength gamma rays at an electron from all directions thus having almost-complete control of both its position and momentum at once?

Thanks!

[Assistant] The short answer is because they don't exist with 100% accuracy. The Heisenberg uncertainty principle isn't about measurement it is about the existence of the information. So no matter how you try and measure something the uncertainty in that measurement is inherent to the particle, an electron is never in 1 place with 1 momentum. Bells theorem, or rather experiments meant to test it, prove that there are no hidden variables that we just cant see.


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

[User] ELI5: How come hitting my tv remote against my hand makes it work again when the batteries are going?

[Assistant]
When batteries get older, they start to 'dry up'. Inside the batteries in your remote there's a substance like a gel (called the battery acid) that's separated by a non-conductive barrier. Part of the gel holds the charge to be used, the other part receives the charge after its used. When a battery gets old this gel can form crystals that make it hard for a weak charge to go through. Jarring the battery by hitting the remote against your hand breaks up and moves these crystals around, allowing the weak charge to flow again.

Really, you should be replacing your batteries at this point. Hitting your remote is just going to break it.


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

[User]
[Harry Potter] How did Bellatrix Lestrange (or anyone else for that matter) reobtain her wand after escaping Azkaban?

I would assume, especially upon life sentence, that one's wand would be broken when one is sent to Azkaban. It just seems like too much of an unnecessary risk to leave a lifer's wand intact.

If wands are broken, another person's wand is not nearly as effective as one that fits just right for you.

So,

1. is there evidence that wands are broken upon having a life sentence in Azkaban, and

2. how does one procure a wand after escaping Azkaban? Is there some black market version of Ollivander's?

I'm just so un-schooled in the ways of the Dark Arts. Please help!

[Assistant]
Many of the Death Eaters who evaded capture appear to have been wealthy, I'd assume there's a black market in everything (there usually is).  One assumes part of the penance paid by those like the Malfoys was supplying the gold to equip the escaped Death Eaters with wands, battle potions, and other necessities.

Obviously high quality wands matched to their owners might not be so easily obtainable, but the escaped Death Eaters would be at least functional with any wand.

Later Voldemort captures Olivander, principally for his knowledge of the Elder Wand and the interaction between Voldemort's wand and Harry's, but presumably also to help the escaped Death Eaters get better wands.  Can't have an army without good equipment.


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

[User]
ELI5: Why is it safe to consume insects whole despite containing poop?

Something I've wondered for awhile about edible insects versus traditional meat is that with meta, we tend to separate the organs, specifically removing the parts of the meat that would be harmful to humans, such as their poop.

However, when a human being eats an insect, we eat it whole, regardless of the waste contains in them.

Is it that Insect poop is simply not harmful to human beings, or is there a process used to clean them during the farming process?

[Assistant]
No human-compatible contagions is why. Poop itself is edible, some of the lifeforms in it are not, and there may be toxins from the food or microbes. Generally speaking, creatures who eat meat have more harmful microbes in their poop, and on the other end of the spectrum Elephant poop is "sterile" enough you can throw it around in a dung fight.

Poop still has nutrients in it. Rabbits actually absorb so few nutrients the first time through, they'll eat their own poop to give it a second pass.


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

[User]
[Marvel] Why is Jean Grey so tormented in the movies?

In the movies her phoenix powers give her nightmares and melt walls etc, and are described as wanting to burst out and difficult to control. What is going on with Jean Grey? Is it the size of her powers that are difficult to contain, or is it the nature of the phoenix inside of her to be wild, or is it some sort of possession? Can someone explain the phoenix better...

[Assistant]
It's literally all three of the reasons you mentioned. The Phoenix is an overpowering force always attempting to fully manifest itself in a girl that it's possessed.

Jean Grey isn't treated so well in the comics, either. Probably worse, actually.


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

[User] ELI5: how is futures trading any riskier than regular stocks if youre just putting in the same amount of money to potentially lose?

[Assistant]
I once read a story about a person who was trading on oil futures. He worked for a small refinery, and they could process a small amount of crude oil. But his job was to try to order futures above that amount when prices were favorable and sell those futures to other people before the delivery date.

That worked great until one period of low oil prices and uncharacteristically low demand lasted much longer than expected and he wasn't able to sell his futures in time. That ended with 3 tankers anchored outside their port carrying 300x more oil than the refinery could possibly unload and created a very large and expensive problem for everyone involved because the ships had other schedules to keep and hurting relations with the shipping companies could long-term affect the refinery's logistics chains.

Stocks aren't physical goods. If at some point the stock stays lower than you expected, you always have the option to wait and see if the price recovers. The worst-case is the company goes out of business and you lost your investment.

But futures have a delivery date, and if you can't sell by then or accept the delivery you're going to not just have lost money on your investment, you're going to have an expensive logistical nightmare trying to figure out where to put 20,000 pigs or 600,000 barrels of crude while angry truck drivers and ship captains are chewing you out.


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

[User] ELI5: Whats the basis for thinking Beanie Babies would grow in value?

[Assistant] They were a collectible item, like baseball cards. People though that when production stopped, the price would rise they would become rarer. As collectors kept them for collections and the number of beanie babies on the market would drop, causing prices to go up. However it ended up being a lot of people trying to sell them to collectors, and not a lot of collectors.


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

[User] [Batman] So let's say I'm a professional henchman who is looking for work. Which supervillain would be the most laid back one to work for? Like which one can I go and get a drink with after hours?

[Assistant]
If youre a strong and reliable henchman, Bane.  Hes more evil than insane, yet inspires genuine loyalty from his men.

But the real answer if you want to safely get drinks with the boss and coworkers is to skip Gotham entirely and move to Central.  Youll have to jump through hoops to meet the union requirements for the Rogues, but as far as supervillainy goes its as safe as can be.


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

[User] How is average GDP growth around 2% but average stock market return is 7%? Is this basically because the rich reap most of the growth?

[Assistant]
This is a stock-flow fallacy. GDP is a flow - it only accumulates over a certain time frame, usually a year. But market cap is a stock - it represents the value accumulated over many years (and also many years into the future, firms that arent productivite today could be productive tomorrow which is why people may still purchase their equities today).

Its really an apples to oranges comparison. There's no reason to expect growth rates in one to be greater than or less than the other.


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

[User]
ELI5: Why do girls like the smell of my sweat?

I've had several girlfriends really like how I smell after I work out; literally smelling my body and armpits. I think it smells gross. What gives?

[Assistant]
Your sweat smells like *you*, and your girlfriends like that.  You probably like what they smell like too.

One thing dog owners do sometimes, when they leave their dog for a while, is leave some of their dirty laundry, since many dogs find their owner's scent reassuring.


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

[User]
You get a donor organ or tissue from a stranger and after natural cell-decay your body renews the cells; then which DNA will be in the new cells?

Stated differently: how long is an implanted donor organ recognisable as foreign tissue? Will it ever be made with your DNA or is it the donor's forever?

And what would change if it was a different organ or tissue?

You can take it further: how much different DNA 'sets' can there theoretically be 'active' in a single human besides the original?

[Assistant]
It is forever the donor's organ, with the donors DNA.  It will never flip to become "yours", so you will have to take drugs for the rest of your life to prevent rejection of the organ by your immune system.

Many DNA sets within the same individual are possible, the problem is with tissue rejection.  If you're interested, look up somatic mosaicism, where it's possible that normal individuals have separate DNA sequences in different cells of their body.


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

[User]
[Star Wars] Can't Jedi use the force to turn the other Jedi's light saber off?

Seriously.

[Assistant]
They could, but without knowing the mechanics of the lightsaber in question, it's not as easy as flipping a switch. Remember, each lightsaber is custom made, and while they follow similar design patterns, the ignition may be dictated by different mechanisms, such as an activation stud, or perhaps an internally switch that can only be reached with the Force.

Additionally, most Jedi and Sith learn early on to protect themselves from Force attacks with resistance methods. Only by wearing down the Force-user, breaking their concentration, punish a moment of relapse, or completely overwhelming their defenses would you be able to attack the Force-user with Force based attacks.

And even if you do just flick their lightsaber off, it's just as easy as flicking it back on. You might as well take the time to directly attack the person rather than disarm them for a split-second.


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

[User] ELI5: How does nuclear power compare to that of others (solar, wind, coal, etc.)? I've heard a lot of talk recently about how it's the safest and most efficient, but I know absolutely nothing.

[Assistant]
Other than solar, which is done using something called a photovoltaic cell, or other solar heat collection methods, power ultimately is generated by mechanically turning a generator.

This is typically done by either mechanically connecting a generator to turbine blades, as in a wind turbine, or by connecting it to a water turbine, in the case of a hydroelectric power station, or in the case of coal, oil, gas, and nuclear, by heating water to turn it into steam, and drive a steam turbine.

The only difference between all of these steam turbine types basically is how the heat is generated to create the steam. That's it. Heat from burning coal, oil, natural gas, or the heat from a sustained nuclear reaction.

The reason they say nuclear power is so efficient is because it creates such a **lot** of heat from a tiny amount of fuel. The fuel in to energy out ratio for nuclear energy is many *many* times greater than any other fuel/heat based power station.


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

[User]
[Star Wars] Could Darth Vader have been more powerful if he did not have his armored suit?

Let's say in Episode III a different event occurs. Darth Vader is in Mustafar, Padm shows up, Vader injures her, Obi Wan shows up, and takes Padm but does **not** confront Vader. Padm gives birth and she dies blah blah but since the Duel of Mustafar never occured, Darth Vader does not get his armored suit.

 Although Darth Vader was still powerful with his suit, could he perhaps be even more powerful if he did not have it ? Could he maybe be faster, more agile and even stronger?

[Assistant]
Absolutely. Mustafar broke him both physically and psychologically. He'd never have the power he once had the potential to achieve.

But Darth Vader was still much more powerful than Anakin Skywalker ever was.

[Meta: This was even directly stated by George, that before Mustafar Anakin had the potential to be twice as powerful as Palpatine, but afterwards he'd only max out at about 80% of Palpatine's strength (and arguably, in Legends, he never even came close to even that).]


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

[User] What is 'information' in the quantum physics sense and how is the idea of conservation of information a valid law when I can think of several examples of where information is lost?

[Assistant]
In quantum mechanics, the fundamental entity you work with is the wave function. It's the wave function that encodes everything there is to know about the system. In that sense, the wave function is information about the system.

Now, quantum mechanics tells you how wave functions evolve over time, we call this a unitary evolution. That's somewhat technical, but in essence it means that the information encoded in the wave function never gets lost, whatever happens.

However, as you object, there seem to be cases in our experience where information seems to be destroyed. Say, you have a piece of paper with a secret code on it. If you throw it in the fire, that information is lost. How does that compute with what we said before?

Well, quantum mechanics still maintains that that information is conserved. The information is now encoded into the ashes, into the heat, etc... The thing is, it is practically irretrievable to us, so to us it seems lost. But in actuality, it is still there and someone with perfect control of all aspects of that situation could in theory reverse the process and recreate the piece of paper, or find the information back in the way the ashes are disposed and the heat of the fire dispersed.


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

[User]
Why do films made in developing nations switch languages so often?

One thing I've noticed while watching Indian cinema is that the dialogue in the films will switch from Tamil or Hindi to Indian fairly often throughout the film, often with a few lines here or there being said in English. In these cases, it often sounds like the English line is in English to emphasise it, but if that's the case, why is English an emphasising language? How does that happen?

Outside India, other countries' films do this as well. The South African film, Tsotsi, for instance, switches between Xhosa, Zulu, Afrikaans, and English, with the characters speaking all of them at different times. Why is there so much language switching? Are conversations in these countries naturally so multi-lingual, or does this exist only in film? If it does exist solely in film, why?

[Assistant]
You're confusing "developing nations" for "multilingual nations". Films from monolingual developing nations won't be making the switches. The switching is a characteristic of the country's language environment and not of their degree economic development. You'll find that North Korean cinema is not making such language switches, nor was old Korean cinema before they were considered fully developed.

~~Also what language is "Indian"?~~


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

[User]
Is not doing a bad thing good?

The original premise for the question was vegetarianism, i.e. if killing animals for the pleasure of eating them is "wrong" and seen as a "bad" thing, is abstaining a "good" thing or simply neutral? If people think that they're doing a good thing by not eating animals, why don't they think that they're doing a good thing by not killing everyone they come across, or not stealing when they go into a store? My first reaction is that perhaps the difference between a good or neutral *inaction* comes from a social moral differing from an objective moral (i.e. most people think that murdering a human is bad, while most people think that murdering farm animals is fine).

However, the question is intentionally vague because I'm interested in different interpretations. Feel free to ignore the premise.

[Assistant]
It probably helps if you have a distinction between "praiseworthy" and "non-praiseworthy" actions, in addition to "good" and "bad" actions.

Sometimes we do good things that are praiseworthy (because they involve a sacrifice, or a great risk, for example) but sometimes we don't deserve praise for doing what we ought to do (like not killing random people that we meet). So, there are some actions we might want to say are good actions, without necessarily saying we should praise a person for doing them.


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

[User]
[Avatar] Why did Avatar Roku battle the volcano?

Sorry for asking so many Avatar questions but there is much unanswered about the show. What was the reason to keep going at it with the volcano? Everyone got off the island so what was he trying to protect? He would have lived if he had just left.

[Assistant]
Partly it was to buy time for a total evacuation, and partly it was to save the homes/shops/farms of everyone on the island. And he wasn't doing all that badly, either.

If he'd been a little younger (and Sozin a bit less of a dick) he'd have survived **and** stopped a large amount of damage to his home.


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

[User]
[The Terminator] What sustained the living tissue that covered the t800 model infiltrators?

What kept the tissue alive? where there reservoirs of nutrients? was there a way for the T800's to ingest food and metabolize it? Did the muculature on top of the endoskelaton provide any measurable strength to the terminator's movement?

[Assistant]
Database quote.

Mankind unraveled the human genome and identified the genes which controlled cell life-span and degradation. Using this information, stored within its vast databases, Skynet was able to eliminate these unwanted genes from cells prior to industrially growing biological components for the Series 800 Terminator.
This means that the skin and muscles of the Series 800 Terminators, unlike the human equivalents, do not wear down, degrade or necrotize over relatively short periods of time. It also means that the T-800's biological components will not rot over long periods of time, and do not require a flow of nutrients or anti-bodies. However, if a T-800 is left on the battlefield for too great a period, its biological components will begin to rot, and its cover will be blown.

Though it does not need nutrient or blood flow, the T-800 has a circulatory system which is controlled by a tiny pneumatic pump which maintains a constant pressure. This allows the T-800 to bleed convincingly when wounded. However, the living tissue of the T-800's is still prone to necrotizing after a period. Therefore, when not in active service, flesh covered T-800's are stored in special racks in a cryogenic vault to preserve the flesh from deteriorating.

In the film The Terminator, after being shot multiple times during the shootout in the police precinct, T-800's skin has a noticeably pale color and flies are sitting on its face. At this point the janitor of the building, which T-800 was using as a safehouse, commented on the smell of decay coming from T-800's room: "Hey, buddy, got a dead cat in there, or what?" Thus the living tissue of Series 800 apparently may "die" or at least undergo extensive necrosis. Nevertheless, in Terminator 2: Judgment Day, when the T-800 was having bullets removed from his back, it explained that the wounds would heal over time. So it seems the living tissue sheaths of the Series 800 are still capable of limited regeneration thus aiding in future infiltration. Judging from the first film, however, the tissue may be damaged so much that the necrosis will spread beyond regeneration.

The sheaths used on the Series 888 Infiltrators appear to be noticeably superior to previous models, as there are many instances where the flesh has repaired extensive damage within a few hours, leaving only scars that would disappear not too long after that. T-888s are also capable of lasting extended periods; one such machine having bricked itself inside a wall for over 40 years. "Self Made Man" These machines also seem to nourish their organic components through consumption of certain foods, including mostly carbohydrates.


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

[User]
ELI5: Gravitational Proportionality constant in the equation g = -(G M)/r^2

Really need help for a Physics project and can only find explanations for G when it's an equation using gravitational force between two objects.
The equation I'm using is for planets or something. (g = -(G M)/r^2)

Any help would be greatly appreciated.

[Assistant]
Any two objects have a gravitational force between them. For most things, they're light enough and far enough apart that we don't notice them.

For objects that have observable gravitational fields, we can clearly observe that the gravitational force "pulling" them together is inversely proportional with the square of the distance.

In other words, when two objects are twice as far away from each other, the gravitational force is 1/4 the strength that it was. If they were triple the distance, the gravitational force between them would be 1/9 the strength, and so on.

Halve the distance between the objects, and the gravitational force doesn't just double; it quadruples.

This is related to the way that space is bent by gravity, and similar equations hold true for light: if you shine a light at me, then move twice the distance away, that light will appear to me to be 1/4 as intense as it was.


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

[User]
ELI5: Why is depreciation considered an expense in accounting?

No matter how many times I google this, I cant truly understand it. I simply dont get why you would consider the lost value of an item over time to be an expense. If I buy a machine for $500,000, thats clearly an expense. Because it cost me $500,000. But if nearly the entire value of the machine depreciates over time, and I sell it for $1 many years later, how would that mean theres another $499,999 expense for depreciation. Isnt that just part of the original $500,000 expense?

[Assistant]
When you buy a $500,000 piece of equipment, you trade the the money for the equivalent value of equipment. The company still has $500,000; it's just been converted from liquid cash to a physical asset.

But when the value of that machine begins to depreciate, your company has lost "money". You no longer have $500,000 worth of assets. That lost money is an expense.


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

[User] [General Fantasy] Why do vampires bitch about the curse of eternal life and being unable to die when they can just walk out into the sun?

[Assistant] Walking out into the sun would be committing suicide, a bit no no in most religions, particularly Christianity.  If you're a vampire that's affected by crosses or holy water, then you can assume committing suicide would condemn you to hell, it's seen as a Mortal Sin.  Better to be undead and walk the earth than damn yourself to eternal suffering.


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

[User]
I want to hang dry my clothes; which would be faster; exposing it to sunlight or a breeze?

Would it be faster to dry a garment indoors against a window that's exposed to direct sunlight, or outside, where there's a slight breeze (but in the shade)?  Basically, I'm asking is the sunlight more effective at drying stuff, or is open/moving air?  Strange question, I know, but I'm very curious.

[Assistant] It depends on the humidity of the indoor room. If the indoor room is small and not ventilated, the moisture from the drying clothes will quickly raise the humidity of the room to the point that is significantly slows down the drying of the clothes. If you place a large dehumidifier in the small, ventilated room, or if you give it good ventilation (open some windows) it will keep humidity low and keep the drying time short.


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

[User]
[MCU] Carol was in space was over 20 years, why did she never go to kill Thanos?

If she protects the universe, isnt the greatest threat Thanos himself?

[Assistant]
Its a big universe. She just never ran into him. Or he didnt make enough of a problem to make her search him out.

And outright killing isnt her style. People said the same about Ronan who was a military commander following orders during their fight at earth. Defeating the fleet was the goal. Not killing someone.

Going by comics Thor with mjolnir shouldve been capable of doing the same to sanctuary II.
Its hard to say how Thor and Carol compare in the MCU but Id give it to top condition Thor.


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

[User] [2000AD/Judge Dredd] I was driving and I almost run over a distracted pedestrian on his PDA, who came out of nowhere. He is now saying that I almost tried to kill him and wants to get a judge to get me sent off to the cubes for life. How fucked am I?

[Assistant]
> distracted pedestrian on his PDA, who came out of nowhere.

Jaywalking is a crime in Megacity One. The perp will probably be spending time in the cubes himself if he calls a judge with that story.


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

[User]
ELI5 Why does spicy food loosen your sinuses?

People always suggest chicken soup and spicy food whenever I'm feeling all stuffed up. Spicy food ALWAYS works. Why is this so?

Thanks Reddit!

[Assistant]
Spicy food loosens your sinuses because your body reacts to the capsaicin in spicy food.

Capsaicin acts on pain receptors in your mouth and triggers biological countermeasures designed to increase airflow and flush out irritants. You experience this reaction as runny nose, eye watering and an increase in salivation.


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

[User]
ELI5: How does a database handle 1 billion users?

I'm really interested in how companies store such HUGE amounts of data but somehow retrieve and display the information in <1s.

I was looking at my Facebook activity for 2010 and it has the thousands upon thousands of posts I liked. You can't possibly store this in some sort of pivot table database, could you? Facebook would have literally 800 billion rows.

And my actual question is, how does a company, like Facebook, store more than 1 billion credentials? Is it split into regions like Users_GB, Users_US?

I work as a web developer. But as I work for a small company, I just can't fathom data this big.

Any insider knowledge, anecdotes and discussion from anyone who works on large databases would be appreciated.

Edit: Went to bed, woke up and the blew up. Thanks for all the great discussion, and thanks for the gold.

[Assistant]
The good news is that data isn't stored in one giant table.  It is actually made up of multiple tables.  Tools exist that then link those tables and read the information in them fairly effeciently.  Oracle, MySQL, etc handle massive amounts of data pretty easily.  Because these tools don't actually care what the data is, they just need the reference points, they can quickly retrieve the data.

Think of how RAM works: fast switching pointers.  This is how you get a user's data out of billions in a table.  The software doesn't need to know that the person's first name is JOHN, it just needs to know that that user's pointer is here and it points to that table and then that table points to the next connected bit of data, etc.  It is a chain of tables.  Again, most of the retreival of the data isn't getting ALL of the data, it is just getting the pointer.  That pointer leads to the next pointer, and so forth.  Just fast swapping pointers and then one DISPLAY of the data.

Big Data as it is termed, is a huge industry specifically for this challenge.  It isn't perfect, but an entire industry exists simply to find better ways to store data so that that pointer chain can be processed faster and faster.


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

[User] ELI5 How do insects climb walls and other flat surfaces and stay attached?

[Assistant]
There are two ways insects are able to hold on to surfaces; tiny hairs and adhesive pads.

Many insects like common houseflies have a large number of very tiny hairs on the bottom of their feet. They can use these hairs to hold on to microscopic bumps in surfaces. The hairs work pretty much like a human rock climber's hands and feet but the difference is that they have thousands of these hairs and all of them combined are enough to hold the tiny weight of the insect.

Some insects, like grasshoppers, have tiny adhesive pads on their feet. Different insects have different types of adhesive pads but they too usually contain numerous hairs and secrete an oily substance that causes the tips of the hairs to adhere to the surface similar to how a wet shirt adheres to our skin.


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

[User]
[The Last Airbender] How could the airbender genocide be successful?

I mean, of all the four nations, wouldn't the air nomads be the most resilient to genocide? They don't stay in one place, all of them are benders, and they almost always have access to their element. I haven't read the comics, so if the answer is there, please don't spoil it and just let me know where to look.

[Assistant]
You'd think so, but at the same time, they were largely a non-violent people. They have few offensive attacks and air isn't that effective at stopping fire. Trying blowing out a camp fire, all you do is supply it with more oxygen and make it burn hotter.

Not to mention, they are technically "nomads" they more or less just traveled from temple to temple, where it would be relatively easy to kill them.

Include the fact that no one expected it, and you have a recipe for a genocide. It's the same thing that happened with Order 66. They attacked the main temples, and then over the course of the next few months/years, they hunted down the remaining benders and lured the rest into traps.


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

[User]
[DC] How do different pantheon and cosmologies co-exist?

So the Greek pantheon exists. Apparently there's also DC original gods called New Gods. Also Yahweh and Satan exist. How do all these conflicting cosmologies co-exist?

[Assistant]
Most pantheons are in some way tied to the culture they represent, and in some sense they belong to the Dreaming. To exist- or at least to interact with our world- they do need some degree of worship or acknowledgement. They don't appear to have "actually" created the universe so all those conflicting accounts don't really conflict.

There is one particular God/divine being (we usually call him the Presence) who lives on the Silver City and isn't beholden to those rules; that Presence is basically the bona fide creator of the Multiverse but it's often hard to tell if we're talking a more Judeo-Christian or deist thing. Or some weird sci-fi thing connected to Perpetua and the Monitors.


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

[User] [WarHammer 40k] What with the 20hr work day, how do HIVE world residents have time to participate in crime on the scale of Necromunda?

[Assistant] Not everyone works.  Indeed, for those who do the Emperor's bidding, those twenty hours are a welcome refuge from the hostile predations of the Hive's social rejects.  Some laborers commit petty crime in their off hours, but gang life is a full-time occupation where the law fears to tread.


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

[User]
Differences between "Orcs" and "Goblins" in Middle Earth?

At times, the two terms are used interchangeably, but at other times, they seem to be described as separate races. Can anyone elaborate?

[Assistant] Technically they are the same. *Orc* is derived from Elvish, while *goblin* is from the speech of Men. In practice, *goblin* seems to refer more commonly to those that live underground, but they are overall interchangeable. Sting's glow reacts to "both."


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

[User] ELI5: different species can't breed, apart from some exceptions like lions and tigers, or donkeys and horses. What stops species from producing offspring and what's the biggest species separation that can produce offspring?

[Assistant]
Picture the information that is given from the mommy tiger and the daddy donkeys like zippers.
Tiger zippers have really big teeth like a snowsuit.
Donkey zippers have really small teeth like those on a delicate piece of clothing.

If you try to zipp the one side of the snowsuit to the other side of the delicate clothes it just won't go.
If the two zippers were similar enough though - like a horse /donkey or lion / tiger... they may just fit. Not perfectly but they might fit..


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

[User]
Why didn't the Thing assimilate Clark?

Blair assumes that Clark has been assimilated because he spent a significant amount of time alone with the Thing in dog form. This turns out to be untrue and Blair may have accused Clark to throw the trail off him and cause paranoia.

However Clark DID spend a lot of time alone with the Thing. In fact, he was the one who put the thing away in the kennel right before it changed. So why not assimilate Clark? He's human, so he had more access to the camp. Plus, and I'm not sure if the Thing knew this, he had regular unrestricted access to the dogs, so that would make assimilation easier.

Why *wasn't* Clark a Thing?

[Assistant]
**Excerpt from [redacted] briefing following the [redacted] [redacted] Antartica incident**
*
This excerpt requires Tangerine elephant security clearance and above. If you do not possess it please leave the room immediately and report to your superior officer.*

-A good question senator. It is important to note that the dog, alaskan malamute was probably the last remnant of the thing from the Norwegian camp which managed to nearly destroy it.

As such, the dog may not have been fully assimilated, and its energy and mass was barely enough to retain conscious control.

Based on the testimony of late mr. Childs, it is important to note that the dog did wander our camp, probably surveying the layout and habits of the inhabitants, possibly planning its next move.

When it has been placed in kennels, its first move was to assimilate other dogs, probably to acquire more mass. With additional mass it could have taken a form which would easily and quickly convert Clark or others.

Our scientists are sure that speed of assimilation is proportional to the mass of extraterrestrial cells involved. The more there are, the faster the conversion. This is supported by the speed new infectees were discovered (according to our reconstruction). The thing was probably infecting dogs first because it could convert them faster and then use its additional mass to quickly convert humans.

Remember, assimilation takes some time, and a dog could not have subdued mr. Clark easily. At best it could have bitten him which would result in slow conversion and medical examination which may have blown its cover. Clark could also have been quarantined from the others.

It is important to note that the thing overplayed its hand and assimilation of other dogs alerted humans. The extraterrestrial is unfamiliar to normal man-dog behavior and probably concluded that dog barking will not alert others. It may have succeeded if not for the late mr. MacReady which forced it to flee and attack openly some of the others.

It is unfamiliar to us how and when extraterrestrial thing assimilated others like Blair, Norris and Palmer. It is possible that it used microscopic traces to poison their food or infect them during sleep, slowly converting them. Its initial plan may have been underway, to slowly subvert all of the humans in the camp.

For all we know, mr. Clark has been already been under assimilation process. Creature has managed to implicate and manipulate others and gain access to blood samples. There is evidence of strategic foresight. It was savvy enough not to convert Clark immediately as he was the obvious choice so it wasnt being targeted for initial assimilation in order to cover its traces.


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

[User]
[The Office US/UK] Given that David Brent appeared in an episode of the US Office, does that mean there are 2 paper companies with almost identical employee doppelgngers who have experienced quite similar events and relationships with one another?

Can we chalk this up to mere coincidence?

[Assistant]
It's a big world with a lot of paper companies and a lot of offices in it. Kind of a spooky coincidence, but weirder things have happened in the world.

If you're superstitious, you can chalk it up to fate, or karma, and that some things are meant to happen.


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

[User]
[Star Wars] I'm a pretty big Star Wars fan, and have read fairly extensively into EU, but something still eludes me: How, other than aesthetics, has technology changed since the Old Republic era?

It just seems like ships go from sleek and sexy, to bulky and square, then back to sexy again, but what changes have actually happened?

Quicker warp speeds? Better weaponry? Are lightsabers still exactly the same as they always were?

[Assistant] Most of the advancements take place under the hood these days. This makes them much less noticeable unless you're a technician that keeps up with them. Think if it this way. Everybody noticed when the Jedi went from using traditional bladed weapons to lightsabers. It's not as noticeable when the power cell inside that lightsaber is made 40% more efficient. You'll notice when militaries start using blaster rifles instead of slug throwers, but you don't notice so much an innovation that allows newer model repeaters to fire more accurately and efficiently.


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

[User] What exactly is incompatible about general relativity and quantum mechanics?

[Assistant]
Not much, actually. Hikaruzero summed up the problem nicely. If this thread comes to the top, there will be plenty of uninformed comments from people who read Lee Smolin's or some other Quantum Gravity book, but please disregard them all.

50 years ago, quantum mechanics was promoted into something called quantum field theory. Quantum field theory, as the name says, tells you how to apply quantum mechanics to classical field theories, such as electromagnetism.

Any undergrad physics students will recognize that electromagnetism looks a lot like GR, in the sense that they are both field theories of a tensor that transforms under certain symmetries. Both theories can be written schematically as: "Curvature = Charge", where curvature is a complicated mix of second derivatives that's invariant under those symmetries, and charge, in EM, is just electric charge, while in gravity is energy.

It turns out that photons are uncharged, so when you produce a photon, this photon will only interact again with another charged particle and ignore all photons around.

In GR, a single excitation of the field - graviton - has energy. So this guy will feed more gravitational field, which is nothing more than gravitons. These gravitons, by themselves, also have energy, so they create more and more gravitons. This seems nasty, but these interactions are very weak once the typical energy is much lower than the Planck scale, and everything is nice and treatable. Once you go beyond the Planck energy, it's impossible to make predictions using the standard technique.

Technically, we say that there are two problems: one is perturbative unitarity, which is the statement that probabilities calculated using "perturbation theory" (which is the only thing in our toolkit to make predictions using QFT) do not sum up to one after you cross the Planck scale. The other problem is non-renormalizability, which tells us that if we try to include contribution of very high energy modes in our low energy calculations, we have unphysical infinities.


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

[User] ELI5: What makes the Venezuelan national debt of 60 billion so much worse than the US national debt of 20 trillion?

[Assistant]
The inability of the Venezuelan government to pay interest on that debt, and keep their own government functional.

In the same way that $1M in debt by Microsoft wouldn't really impact anything, but $1M in debt by me would be crippling.


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

[User]
ELI5: Why can't adware/pop-ups trick you into clicking them through the X button that closes the pop-up window?

What I mean by this: for example on an Android phone there are pop-ups and similar things in apps and browsers - is there a real risk of getting infected with adware by clicking the X button to close the window?

If not, why? Isn't there a way or method of linking something to a button that closes a window? Same question applies to Windows as well.

EDIT: mean*

[Assistant] I can't speak for Android, but on desktops the close button is part of the browser, which doesn't permit websites to modify its function for just that reason. Web content relies on the browser or plugin to execute it; if the browser doesn't support something, it won't happen. However, sneaky adware often includes its own button that simulates the one on the real window, hoping users will inadvertently click that.


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

[User]
ELI5: Why are stimulants like adderall only therapeutic to people with ADHD, and not recommended for normal people improve performance?

It seems confusing that these drugs are meant to be taken everyday despite tolerance and addiction risks. From a performance perspective, wouldn't one be more interested in spacing out dosage to reset tolerance? Even with stimulants like caffeine, do you get the most bang for your buck by taking it every day in low dosage, or by spacing them out some amount?

[Assistant]
Theyre not prescribed for performance reasons because of the risk of addiction (and other negative health effects). Those downsides are only considered worthwhile if theres a significant problem that they would solve. This is the whole point of *prescribing* certain medicines rather than making them freely available, and stimulants arent the only example of medicines restricted in this way.

The benefits may also be smaller for people without ADHD. Stimulants improve focus and energy, and are used illegally to improve performance (especially with academics). But if a person is *able* to focus on a task consistently/long-term without the drugs, the possible improvement is smaller than somebody who cant do that at all.

With ADHD, consistent use is part of a treatment plan that intends to develop good *habits* as well as methods like organization to support better productivity, focus etc.

Without the need to address those issues or maintain structure/consistency as part of the treatment plan, consistent use may have more downsides (tolerance etc) and occasional use would be better.


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

[User]
ELI5: What is the evidence against Lance Armstrong and why did he fight it for so long?

I've heard the evidence against him is overwhelming. Why would he choose to just deny and fight? Wouldn't other strategies be better for his reputation, especially in the long run?

[Assistant]
The evidence: about 20 of his former teammates, who are mostly still in the sport (riders, but also teamleaders and such) have testified, knowing that it could be harmful for their own careers, that Armstrong has doped. Among those are George Hincapie, Armstrong's former master servant (I don't know how 'meester knecht', as the Dutch and Belgians call it, translates best into English) and Jonathan Vaughters, head of Garmin. There are also samples of his urine and blood, which contain drugs that couldn't have been found earlier, because the technology wasn't able to in those days.

Why does he fight it? Money. Reputation. As long as he keeps fighting, there will always be people believing in him. If he gives in, the 10+ years of fighting he did would become fruitless, and the people who had been supporting him through all those years would be proven wrong to do so. And money, because Armstrong sued anyone who claimed he used drugs, often getting large sums of money from these lawsuits. Also, promoters gave him large sums of money if he would win another tour. Al those people will be demanding their money back if they know he didn't win those honourably.

Really, Armstrong can't win this one. He's royally screwed right now, and will probably go bankrupt.


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

[User] [Pokemon] How would things be different if Brock had chosen to capture Charmander instead of letting Ash have it?

[Assistant] Brock wouldn't tolerate any of Charmander's sass as it evolved, since he's far more experienced and strict with his pokemon than Ash is. It probably would have stayed a Charmeleon once it understood what Brock expected from it, and become disciplined with good physical attacks.


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

[User]
ELI5: How does a salt water rinse work for toothache/inflamed gums?

I had my wisdom teeth taken out and I've been using an anti-bacterial mouthwash (chlorhexidine) but I've found a salt water rinse actually works better for getting rid of the pain/inflammation/aching.

So why does something as simple as salt and water work better than a dentist recommended antibacterial mouth wash?

[Assistant] warm Salt Water works well because it's a hypertonic solution, means that the osmotic difference between the solution and the tissues is such that it will pull water OUT of the tissues.  The inflammed tissues will have excess water in it, and the hypertonic solution will calm it down by pulling out the water, allowing it to thin down and not be so "angry".  It also acts as a mild disinfectant because the salt solution does the same to any bacteria that are around.


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

[User]
About the instability of academia

 Is it possible that the lack of career opportunities are hurting your research?

I'm doing a PhD, I will not be ready on time and I feel a rush to just deliver whatever before my funding runs out. I don't anymore about quality as I see it now, I will be out of academia after I get this degree. But I truly wonder if things would've been different if I had a long-term contract or at least some certainty about my career. Right now, it is as if I were in dead end.

[Assistant] Absolutely. This is also noticeably worse for people from lower-class backgrounds who don't have a family to fall back on for financial support if things go sour with their job searches. Constantly having to grapple with the knowledge that you might do everything right and still get evicted or go hungry isn't exactly conducive to creative higher-level thinking...


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

[User]
[Prototype] Can Alex Mercer take animal forms?

Alex Mercer was described as being capable of copying and combining the DNAs that he had absorbed. This ability give him the power to change his physical structure and appearance.

We know that he can consume animals as he has consumed a crow. Could he theoretically transform himself into animal forms if he absorbed the necessary DNAs?

[Assistant]
Yes. However it wouldn't be as simple as it is to transform into another human. For humans, he already has a complete set of DNA that he can compare the two together and create the DNA sequence that looks like the person that you want to conform to.

When he absorbs a human, he also absorbs their clothing as well, and can replicate them to look the same. He can do the same thing with animals, but he would need to absorb a lot of animals to get a complete shape (or evolve to be better at absorbing DNA. He's always getting better at absorbing)


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

[User] ELI5: Joker's Philosophy (in the dark knight)

[Assistant] The Joker went crazy after a seriously screwed up personal loss ( nightmare level stuff) and he tries to break people down morally so he can prove his point that given a certain situation, anyone will be as crazy and "evil" as he is. He does this by terrorizing them and putting them in horrifying, impossible situations. He does this several times in the Dark Knight film: on his two new henchman ( kill each other, winner joins me), on the people ( blow up the other boat or get blown up) , on Batman ( choose who will live or die). He also did this to James Gordon in the award winning comic  "The Deadly Joke". Why is this so important? Because Batman is the one the Joker HASN`T been able to break down morally. Despite everything the Joker has done, Batman has never killed him. If Batman kills Joker, the Joker WINS. And Batman knows it. They`re both struggling to prove their principle is the valid one and to prove that the other has a wrong view of the world. This is why their fight is so important, so chemical, and has lasted so long. It`s a very very personal struggle.


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

[User]
ELI5: In American tv shows, why are the FBI normally shown as the good(ish) guys and the CIA as the bad guys?

Maybe it's not always the case but It's a pattern I've noticed.

[Assistant] These shows are often police shows. The FBI is a law enforcement agency and the CIA is not; when something involves the CIA it's generally not a good thing, especially within the US where they aren't supposed to operate.


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

[User]
Turkey's interest rate

As of recent, Turkey has been a main stay in the news due to its rising inflation and the devaluation of the Lira. A common talking point is the government's counterproductive course of lowering the country's key interest rate. The lowering of the country's key interest rate from NINETEEN FUCKING PERCENT TO FOURTEEN PERCENT. Turkey's key interest rate is at 14% while most of the world is edging ever more closely towards 0 or even into the negative. Can someone explain that to me?

[Assistant] The policy rate is 14% yes but headline inflation is over 21% (so far), meaning the real interest rate is negative. The quick answer is you're basically losing over 7% in anything denominated in Liras. That's why Dollarization has shot up to over 60% (percent of fx deposits to total deposits), stocks crashed, and of course the the Lira collapsed.


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

[User] ELI5 Why does installing a game/program sometimes take several hours, but uninstalling usually take no more than a few minutes?

[Assistant]
Allocating space is buying a plot of land.

Installing a game is building a house on the plot. This takes some time to unpack and use materials (data).

Uninstalling a game is putting up a "For Sale" sign on the property. Everything on the property still exists until it's rebuilt (rewritten).


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

[User] [Fallout] Why doesn't the Brotherhood use the more advanced enclave armor?

[Assistant]
I think the basis of their logic falls on reserves. The T-60 is abundant, and they know it well. Some higher ups have special armor, but in general the same rule of thumb applies to old world military. We could put every soldier in Kevlar/neoprene combat armor, but it's easier to stick with camo fatigues and save the elite gear for the elite crew.

EDIT: Those responding, consider this is the fallout universe, not ours. The reality we know has little relevance. Comparison of modern day military is as helpful as comparing the star wars universe standard outfitting, which is not at all.


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

[User] ELI5: why is it so easy to fall asleep on your couch even with desperately trying to stay awake, but after dragging yourself to bed, you find yourself wide awake and unable to get back to sleep?

[Assistant]
I think this is a psychology rather than biology question.

The answer will vary from person to person but broadly it's likely to be that when you're on your sofa you're in your relaxation frame of mind so you can go to sleep but when you start your bed routine you start thinking about plans for the next day so you a/ get your brain working and b/ start worrying about how much sleep you need so can't relax.

It's basically a 'sleep hygiene' issue, meaning your bed routine isn't helpful.


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

[User]
Seriously considering leaving my PhD program - advice?

I am 4 years through a 6 year PhD program in Biology from a big name school. I'm an international student on an F1 visa, so I moved to the US specifically to complete this program.

Four years down and I am desperate to leave. My physical and mental health have both suffered due to the stress of the program and also a difficult relationship with my advisor, and my productivity has slowed to a halt. At my current rate of data generation, I'm afraid that I won't have enough to satisfy my committee and graduate two years from now. I'm not enjoying the project, and the thought of switching to a new project with the same advisor makes me feel depressed and anxious. The rest of my lab is wonderful - I would be really sad to stop working with my colleagues, but I have worked very very hard on trying to find a synergistic relationship with my advisor, and frankly I've lost my trust in this person. I'm very resentful of many past events and the style in which my advisor chooses to "advise", which is very controlling and critical.

I've learnt that I want to work in science but the kinds of jobs I want are typically advertised at the Masters level. I want something 9-5-ish, field is flexible. I am very motivated by feeling useful and by working in close collaboration with other scientists (I think part of the struggle I've had with PhD is that I don't enjoy the solitude of being solely responsible for completion of my project). I'm happy to work overtime occasionally but I want to have evenings and weekends to myself, for the most part.

So! If I left, I would have a Masters in Biology from a big name school, and plenty of experience (4 years from PhD work + 4 years research experience prior to this). I am confident that I could have a fulfilling career without a PhD. My major issue is that I don't want to leave the city where I'm currently in school! It feels like home now. But I'm dependent on my student visa. I would be able to apply for OPT extension of my visa after graduating with a Masters, I believe, but this extension lasts at most two and a half years. I believe my only other options are:
-H1B visa, of which there are a limited number available per year.
-Green card by employment sponsorship, which AFAIK is typically only offered to employees who have been working at a company for a number of years.
-Green card by Diversity Visa Lottery, which of course is luck of the draw. I'm from a country that is eligible and has a relatively high rate of winners per number of entrants, though.
-Green card by marriage. My partner is a US citizen but marriage isn't on the table right now, and I don't think either of us really like the institution of marriage anyway. And of course marrying someone does not guarantee that a green card application will be approved.

I'm seeking advice from my department and career services at my school, but I would love advice from anyone who has the time and inclination to provide it. Thank you!

[edited a few things for clarity]

[Assistant]
Don't stay in school just because you don't want to move. That's the wrong motivation.

If an M.S. is all you need or want, and you basically have it, then great! You're done! Move on with your life.

If you're close to the PhD and think you might need it (and don't want to move anyway) then why not put in a little extra effort and just get it?

No one here can make important life decisions for you, and you shouldn't let them. Just weigh up the costs and benefits. You know that cheesy old suggestion about making lists of pros and cons? It might be worth doing that.

But honestly, it sounds like you want to take the MS and be done, but you just want validation. You feel like you're being a quitter and might be making a terrible mistake that you'll regret later, right? You want us to tell you that it'll be OK and you should just go for it, so you're not so nervous?


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

[User]
Are there tasks that can be done more efficiently by government than by private enterprise?

There is an idea in contemporary culture that businesses are simply better at most tasks than government because they are motivated by profit and literally can't afford to lose money. Are there nay tasks, though, that can ONLY be performed by a government, or that can be more efficiently done by a government?

[Assistant]
One typical example would be natural monopolies. It just doesn't make much sense if companies all had to build their own electricity network for example.

Another typical example are public goods. Public goods are defined by being non-rivalous and non-excludable, and because of that often suffer from the free-rider problem. If you just make people pay for them via taxes, that's often a simple way to avoid that.


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

[User]
Why is Chlorine so effective in killing anything alive?

What happens chemically and physically when an organism gets in contact with this substance? Why is so deadly?

[Assistant] Chlorine is a very effective oxidizing agent, meaning it is capable of oxidizing a lot of things while itself getting reduced in the process. Intuitively, this makes sense because the chlorine atom is very electronegative (meaning that it's happier existing as reduced Cl- anions as opposed to neutral Cl in Cl2). Chlorine also has a very positive standard reduction potential, meaning that it is capable of reducing anything with a lower potential, which just so happens to be most things. Because of this, chlorine can attack a huge variety of molecules, including most carbon-based compounds. Thus, it can effectively destroy living things.


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

[User]
ELI5: The accelerating expansion of the universe means other galaxies are moving away from ours quickly, but why is nothing within our own galaxy expanding, like the distance between the earth and the sun?

Or why is that that the expansion is between galaxies and not between every single point in the universe? What's special about galaxies?

[Assistant]
That's actually really simple:

Gravity is stronger than the expansion of the universe at relatively small distances.

That is, gravity is sufficient to keep our planet, solar system, and galaxy from responding to the expansion of the universe. It's like a leash that keeps everything tied together.

However, at larger distances, gravity is *not* strong enough; it's a field force that obeys the inverse-square law, which means that it gets much weaker as the distance between two objects increases.

So, the force between galaxies is not enough to hold those galaxies together--but the force within a galaxy *is*.


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

[User] ELI5: Where does all money and wealth go in the recession?

[Assistant]
The cheeky answer would be that rich people and banks are hoarding it. But that's (kindof) a misleading understanding.

A recession is when spending and investment slow down. Consumers are afraid to make purchases, banks are afraid to make loans, businesses and investors are afraid to make investments in expansion. So instead of money *circulating* and moving quickly between buyers and sellers and lenders and debtors, people are kindof holding back, keeping what they can in savings, not taking any risks.

Also, and perhaps even more importantly, some of the "money" wasn't exactly there in the first place. Loans/debts were getting passed around and treated as if they were money, but then some shock or failure happens and it turns out some of those debts aren't going to be paid eventually, they're just going to default. So that debt someone owns that was supposedly "worth" $10,000 or something is actually only worth $2,000, or maybe even just 0. Money gets wiped off of balance sheets.


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

[User] ELI5: Why do we get cranky when we are tired?

[Assistant] We get cranky because evaluating our responses to stimuli takes energy, which our brain doesn't want to use, so we just spout off. And our brains also turn off reward hormones, because it doesn't want to be tired. So you're not getting endorphine boosts.