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

[User] ELI5: The US is over 18 trillion dollars in debt, why are we considered a wealthy, stable country? And why aren't more people freaking out about our debt?

[Assistant]
1) The US has never missed a payment

2) The US has a strong economy that's rebounded nicely, and a huge amount of natural resources still available for development

3) The US government as a whole has an annual revenue of about $6 trillion, so $18 trillion isn't insurmountable

4) A majority of that $18 trillion in debt is held either by the government itself or the people and businesses of the US.


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

[User] ELI5: Why are corporations considered a person and why was it necessary to implement this?

[Assistant]
Corporations are not people, as much as some politicians and pundits would like you to believe, however, in order to do business, they have to be granted some of the same rights as people. People and pets have the right to not be physically abused, but that doesn't make pets people.

As a REPRESENTATIVE of a group of people, a corporation needs the ability to do things like enter into contracts, be taxed and act as a single entity for a group of people. Corporations also shield individuals from the liabilities of a company. If a company goes bankrupt, the debtors can't take money away from the individual shareholders.

Basically, a corporation is a legal construct to allow a group of people (shareholders) do business.


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

[User] [DC] I'm going to a Furry convention in Gotham City. Is the fact that my Fursona is a bat going to cause any problems?

[Assistant] Just as long as it's not too realistic. You don't want to be mistaken for Man-Bat and get punched by Batman. And it can't be too lazy, with just a bat cape and a helmet or hoodie with ears on it, either. Then you might get mistaken for Batman and get punched by Man-Bat.


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

[User] ELI5: the problem with Monsanto and its rise to becoming such a prominent monopoly.

[Assistant]
Farmers like to plant crops year after year and like to fight off the insects that attack their crops.  Crops normally produce seeds that can be used to grow crops next year.

Monsanto sells special seeds that can be activated to be resistant to insects. All you have to do is buy new seeds every years since these crops do not produce useful seeds. You also have to buy the chemical to activate the seeds.

It is much more complicated than that, but the idea is that once they have you as a customer you can never leave. Every time you try to leave, they pull you back again.


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

[User]
ELI5: Why do most rifles use rotating-bolt system instead of straight-bolt system?

I read that the purpose of rotating-bolt action is to lock the cartridge inside the gun chamber, but isn't the cartridge locked the moment when it's inserted into the chamber ? I am still confused about the locking mechanism, like what does it do to the whole cycle of the gun mechanism ?

***Additional question:*** Semi-auto rifles had been around way before World War II, and they are known for their advantages of having better rate of fire and mostly larger capacity than their bolt-action rivals. Then why weren't they as widely used as bolt-action rifles during World War II era ?

**Thank you.**

[Assistant]
The barrel is just a tube with a very particular shape. The cartridge can simply fall out if nothing holds it in. The bolt of a rifle is kind of like a key. By inserting and rotating, it locks. You can't rotate your house key 90 degrees in the lock and pull it back out again, and it's the same way with the rifle bolt given that the rifle is built of thicker, sturdier stuff.

As others have stated regarding bolt action guns used in WWII despite the availability of semiautomatic weapons: bolt guns were cheaper to make and repair, accurate, already familiar to the troops, and already in use with the military. Many WWII military forces saw semiautomatics introduced during the war, even if the standard gun was still bolt-action.


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

[User] Why do ants "collect" the dead bodies of their fallen comrades? What are they doing with them?

[Assistant]
Ants are farmers.

The pick up dead things and carry them back to their hill and take them to a chamber deep in the colony.

Then they leave it there and mold grows on it and the ants eat the mold.

So, they are likely "recycling" their fellow ants.


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

[User]
[Iron Man 2] How did Tony Stark get the Mark 5 Suitcase Emergency Suit through customs all the way to Monaco?

How did Tony Stark get the Mark 5 Suitcase Emergency Suit through customs all the way to Monaco? Would he not have had major issues moving it from America to France since it's considered a weapon?

[Assistant] Private aircraft often expedite the customs process with specific customs officers inspecting private jets.  Provided he had the details worked out beforehand with higher level officials, those officials would just tell the customs officer inspecting the craft that everything is on the up and up, and all would be good.


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

[User]
When is a good time to take a year off?

I am in the dissertation phase of my doctoral studies. Ultimately, I want to build a career in academia in the United States after I gain my PhD. However, due to family and visa reasons, I need to live outside of the United States for a year.

It is very unlikely I can do a job in academia (postdoc, adjunct, etc.) during this time due to visa and language reasons although I hope to get some sort of job to earn some money.

My question is, do you think it is better to take this year off before I complete my PhD, essentially taking 6 instead of 5 years to graduate, or to take the year off immediately after I graduate?

I cannot take the year off any later than immediately after I graduate, again for visa reasons. In other words I have to start the year off by May 2019.

[Assistant]
Maybe this is a field thing, but would you really need to take a year off of writing your dissertation (add a year to your plan) to take a leave of absence for a year?

If no, the least disruptive plan would be to take a year off while you are writing up the dissertation and return to finish it (which will help you apply for jobs). And if your family reasons are sufficiently compelling, you could get a leave of absence that pauses the clock for your expected time-to-degree, so you take an extra year but not according to your registration.

Separately, if your visa is to the US, you might struggle to take a year off after you graduate if you intend on returning to the US to seek academic employment.


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

[User] [DC] Does Hal Jordan's insane willpower aid him in everyday life? Does he procrastinate less than the average human bein and drag himself out of bed without complaining as much?

[Assistant] The real question is, when he realises the show hes watching is turning to shit, does his iron will give him the strength to quit before it goes full werepanther or the stamina to power through season after season until the bitter end?


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

[User]
If inflammation is bad, why does our body do it?

I constantly see "anti-inflammatory properties" listed as a health benefit of various nutrients in healthy foods, but my understanding is that inflammation is a natural process of the human body. So anti-inflammatory foods are basically inhibiting a normal biological process.

Why do we need to do that to be healthy? Why do we have a self-destructive inflammatory behavior in the human body anyway?

[Assistant]
Inflammation is like a pulled fire alarm. When shit us going down and you need first responders, Inflammation is them showing up. Redness and swelling means police, ambulance, and fire trucks are at the scene.

When you have an injury or infection, boom, Inflammation. Kill off baddies, mobilize the troops.

Inflammation can be too much of a good thing. It *can* get in the way of healing. Like if police, fire, and ambulance are blocking construction crews and normal traffic? Sometimes you need anti-inflammatory medicine to heal better.

What's bad news is if the fire alarm is *always* ringing. Or always ringing at 50% volume. Ugh. First of all it means that stuff is getting choked off by emergency services *all* the time, and second, in a true emergency what sort of response will you get? Police fire and ambulance are deployed all over the place already, they're stretched thin. Normal maintenance can't happen and firemen are hacking down perfectly good doors with their axes.

Anti-inflammatory foods, exercise routines, and such help to turn down/off the constant fire alarms so that the rest of your body can renew and repair and go about its business. And then when a real emergency happens, you get a high contrast from baseline normal. Not an everyday thing.


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

[User] [Dexter's Lab] Why does Dexter, the child of two Americans who is living in the US, have a German accent?

[Assistant] I always figured he was intentionally putting on the accent to seem important or more "scientist".  It doesn't seem to really match any real accent, so he's making it up.  That or another _omlette du fromage_ verbal device type accident that he didn't reverse.


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

[User]
If the sun went out for a second and came back, would anything happen to us on Earth?

I understand that we will see the "blink" of the Sun only after 8 minutes, but what will be the effect of the sun going out for a second? If nothing significant, how long does the sun have to be out for anything drastic to happen here on earth?
Thanks.

[Assistant]
If the sun going out meant a sudden break in the magnetic field, a mass ejection of material, or even a momentary but significant change in the gravitational force, then we would see a huge effect, ranging from showering us with highly energetic particles to flinging us out of orbit.

If you just want to know what would happen if the light from the sun didn't reach us for some reason.  Well, that's essentially what's happening with a solar eclipse.


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

[User]
ELI5: Why denying the Holocaust is not protected under the freedom of expression? And why denying other genocides/mass killings is not criminalized in any countries?

I'm not a denier, but this dilemma has always baffled me.

[Assistant] In the US, denying the Holocaust IS protected under freedom of expression.  In some other countries, even those with fairly liberal free speech policies, there is not the same blanket free speech protections as in the US, and specific forms of expression (like hate speech) can still be forbidden.


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

[User]
When people typically die from poisons or toxins that work as inhibitors for vital enzymes (ex. cyanide), how does a relatively small concentration of the poison/toxin completely disrupt a much larger network of enzymes so quickly?

For instance I am familiar that cyanide poisoning  works by permanently inhibiting cytochrome C oxidase for example. But when someone ingests a tiny capsule of cyanide, it is enough to affect enough of the enzymes so quickly that the person dies instantly.

How is this possible?
First of all, isn't there way more cytochrome C oxidase enzyme molecules in the body compared to the cyanide molecules in the capsule?  Even if it is very readily absorbed, by these enzymes, wouldn't the reaction taper off at some point being that the cyanide would be the limiting factor?

Or do these molecules work by denaturing the enzymes and then detaching and moving on to the next enzyme?

[Assistant]
It has a lot to do with relative concentration. Lets say you take in a gram of cyanide and it all gets into your blood. You have about 5 liters of blood at any time, and cyanide has a molecular weight of about 27 g/mol. Therefor your blood becomes about 7.5 mM cyanide.
Cyanide is an irreversible enzyme inhibitor-- once it complexes with cytochrome C oxidase it inhibits it forever.
Now consider the number of cytochrome C oxidase enzymes in a body- lets lay maybe 1000/mitochondria so maybe ~50000/cell * 60 trillion cells -- on the order of 10^18 enzymes in your body. We just calculated though that the number of cyanide molecules was on the order of 10^22-- if we look at it as a ratio cytochrome c oxidase is 0.000005 as concentrated as cyanide. That means that the rate limiting steps are the diffusion rates of the cyanide from the stomach to the blood, blood to intersticium, intersticum to cell interior, and cell interior to mitochondria, etc.

That's a very rough calculation, but you get the idea that in fact inhibitor is in far excess of enzyme.


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

[User]
CMV: Networking is the same thing as nepotism and cronyism

The only difference is you have to work on getting the connect. Even if you disagree, the three involve getting something primarily because of who you know. Meritocracy may play some role in it, particularly for specialized fields but the three -isms come in place for positions where literally anyone partially competent can do, whether its a low or high authority role.

Even though networking requires people to be proactive, those initials starts are largely driven by socioeconomic status. Someone who comes from a low class background can benefit from it, but their success is not as likely to go as far as someone who grew up in an affluent family, with parents who could connect them to some super important people.

[Assistant]
I think you may be relying on how networking is portrayed in pop culture. But typically what is being portrayed is just nepotism dressed up as networking for dramatic purposes.

Real networking is pretty boring and looks like regular old "work". It isn't just knowing people, it's actively engaging in your profession's community. Corresponding with your peers, participating in conferences or committee's, volunteering, etc. Doing things that push your profession or industry forward. Not only getting your name into people's heads but showing them that you are both capable and actively give a shit.

Meritocracy gets thrown around a lot in discussions like these, but always in a self serving way. Most often "merit" is boiled down to a strict, mechanical ability to accomplish a strictly defined set of tasks independent of any human interaction. But most jobs aren't a strictly defined set of tasks that can be completed mechanically. If a job does fall into that category it's most likely a low skill position anyway. Merit is ultimately defined by those doing the hiring and being a know quantity can give one candidate a lot of merit points that often out weighs raw ability.


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

[User]
ELI5: For me to make money does someone else in the world have to lose money

If for example i have $1000 more than last week does that mean that collectively everyone else is $1000 worse off?

[Assistant]
The simplest way to understand this is through an economic concept called Pareto improvement.

Any trade is a Pareto improvement if both parties regard themselves as better off for having made the trade. Imagine buying a hamburger. You prefer having the hamburger to having the $2 that it costs (otherwise you wouldn't have bought it and would have kept the money) and the restaurant prefers selling you the hamburger than keeping it (because they make a profit).

By buying a hamburger, you have slightly increased the total value of the global economy, by improving the efficiency by which resources are allocated. The same principle applies to the vast majority of trades - if both parties didn't think that they would be made better off for making the trade, then they wouldn't do it.

The vast majority of trades in a functioning economy are Pareto improvements. Every time one of those trades takes place, the total wealth of the world improves slightly, because the underlying resources have been allocated in a way that provides a greater amount of utility. Not all of these transactions are ideal, but they're better than no transaction at all.

Situations in which trades are made with no Pareto improvement are sufficiently unusual that they have a specific name in economics, a "market failure". Examples of market failures include things like monopolies (where someone can control a market and coerce people into making unfavourable trades) and pollution (where a third party is made worse off by an economic activity).


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

[User]
ELI5:What's happening in my body when I take energy shots like 5-hour energy?

I've been taking them for so long and have always wondered the long term effects. It always feels like a weird form of undeath. Where I can't close my eyes but I know I'm still tired. Am I borrowing time from future me to power current me?

[Assistant]
Caffeine is classified by drug scientists as a "Adenosine Receptor Antagonist". In your brain, the neurons release waste products as they work, and one of these waste products is Adenosine. Your brain has Adenosine Receptors that gauge the level of Adenosine in your brain fluids, and when the level of these waste products gets too high, you brain gets sleepy--as most of the waste cleaning action occurs when you sleep.

Caffeine is a molecule that resembles Adenosine and thus can fit on to the Adenosine receptors and turns it off (receptor antagonism). Without the receptors active, your brain is unable to get to sleep--so your body may be tired, but your brain is unable go to sleep.

As for the rest of the stuff in energy drinks (e.g. taurine, gensing) testing do not show that they have any effect on alertness.

After drinking so much caffeine, you have reached a state of tolerance toward the caffeine, where your brain has essentially adapted to the constant level of caffeine in your system. So for you, normal = caffeine, abnormal = no caffeine. Caffeine also affects other systems in the brain, such as the GABAnergic, serotonergic, and dopaminergic systems, and upsetting those systems leads to the symptoms of caffeine withdrawal (i.e. the twitching, anxiety, etc).


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

[User]
[MCU] Can Loki fool Heimdall with his illusions?

We've seen him do the old bait and switch many times, where he casts an illusion of himself, but in reality is standing nearby. Would this trick fool Heimdall?

[Assistant]
Probably, yes.

Heimdal likely would believe Loki's tricks too cheap to work, while Loki has likely carefully planned to have Heimdal see through just enough of them to believe that they are poor illusions.


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

[User]
Who's ultimately going to be paying for the loan forgiveness?

I just had 20k forgiven and I'm pretty happy. But I'm curious.

I asked a question previously about where the money would come from and someone said it's an asset on the governments balance sheet and a liability for those who took out the loan.

I hear right wingers complain that they have to pay for it through their taxes, but will this have any effect (long or short term) on taxes? Are the universities going to have less money or funding because of this?

[Assistant]
The government for the most part doesn't spend specific money on specific things. It's not like capital gains taxes pay for one thing, income taxes for another, etc.

Really, it's more that the government has a big pile of income from various sources and a big pile of expenses from various sources.

So, what can a government do when expenses go up, or income goes down?

They can cut other expenses. They can tax more. Or they can borrow more (which is ultimately also just future tax revenue).

Taxes tend to be rather inflexible in a way, meaning the government doesn't change tax rates very often. Tax revenue still rises and falls, mostly with the economy (during downturns, people lose their jobs so the government earns less in income tax for example), and the same goes for expenses (unemployment insurance is used more during downturns) and the same goes for the opposite direction during booms.

In the short term, the government will just compensate revenue shortfalls via borrowing, in the longer term student loan forgiveness is just a small part of the big pile of expenses.

But from a different perspective, everybody who didn't receive this loan forgiveness is paying for it either directly (through taxes or more debt that has to be financed by future taxes) or indirectly (because the government can't spend this money on anything else now).

Of course that's not necessarily very meaningful. We all pay for things we don't personally benefit from. At least not directly. Your social security dollars are going to some grandma you've never even met and never will. Well, at least a tiny fraction of them, just as your taxes pay for schools nobody from your family or friends will ever attend, and they pay for firefighters saving a house from people you don't know. That's how essentially every country on the planet works. We *all* run on the same basic social contract of handing over a portion of our money to be spend on society at large, not anyone in particular, because that's the only halfway decent way to run a society.


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

[User] ELI5: Why is it that animals such as a bat or sloth can hang upside down for long periods of time but a human cannot?

[Assistant] Humans would suffer because we haven't evolved to maintain that position for very long, and blood would struggle to flow correctly, and begin to pool in the head. Bats and sloths by contrast have specialized valves and muscles to compensate for gravity when they're inverted. In their case blood is still distributed correctly, and doesn't just pool in the head.


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

[User]
Doctors/EMTs, what should be (more) public knowledge for saving people's lives?

I've heard CPR has changed a bit in the past few years (reddit post earlier today with a sub-discussion on it, but I cant find it), is there anything else that the average person should know about to help save lives in the event of something catastrophic?

Side note for readers: U.S. Military teaches to tourniquet the "Long bones" to stop blood flow to an extremely wounded limb (gunshot). Also for someone who passes out for lack of blood (if not a leg, abdominal, or head injury) to raise/bend the legs - it increases bloodflow to the head.

[Assistant]
If you ever have a puncture wound, or see one, do not remove the puncturing object. Pulling it out will only cause more damage and allow the victim to lose blood. No matter how creepy it looks, leave it in and let the surgeons deal with it.

That goes double for an eye injury. Always leave a penetrating object in place. If EMS is not available and you must do *something*, just tape a paper cup over the object and the injured eye, and bandage or patch the other eye to stop the victim from looking around.

The Red Cross offers classes in first aid and CPR. IMO, everybody should take one.


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

[User]
[WH40K] How powerful is the God Emperor of Mankind?

A lot of people seem to think that if the Emperor reawakens humanity will steamroll the galaxy. Is he really this strong?

[Assistant]
Yes.

Let me explain how powerful the Emperor is.  He conquered a C'tan, the Void Dragon, and sent it to Mars, while we were circlejerking over a dude getting a sword from a stone (which is not how you determine a government).

This ~~man~~ God showed himself to the World, and basically instantly conquered it.  Then he landed on Mars and instantly conquered it.  Meanwhile, he made 20 Primarchs of massive power.  Then made them each a Legion.  Then sent them off conquering while he reclaimed the 20 Primarchs.  And then went off conquering.  And undid what millenia of warp storms did to Humanity - reunited them.  His death brought the Imperium to its knees, a single second away from a second civil war after the first.

This God is so strong that when he powers the Astronomicon, he burns out a thousand, out of millions, of psykers **a day**.  He is so strong that even in his almost dead state, killed the Warmaster Horus in what amounts to one fell swoop.

The God Emperor **will reunite Humanity** and fuck everyone up.  He is that powerful.


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

[User]
ELI5: How gamers discovers cheat and easter eggs in videogames?

How is it possibile? I think of certain button combination on games like GTA.

[Assistant]
By pushing a lot of buttons.

No, really, once a popular game gets out into the wile and has a lot of people playing it, the odds of a rare event (edit) **not** happening approach zero. Infinite monkeys on typewriters and all that.

Another way is through reverse engineering. Coders and crackers analyze the object code and data assets of the game. Fundamentally, this all has to be presented to the computer or console (which are just computers now a days). If you control the computer, you can look for buried treasure.

Say you're walking through a particular section of code that has to do with....  checking the location of the player in GTA.   You notice a  strangely specific sequence of conditionals (if statements), that check to see if the player is next to a movie theater, it's the right time, and he hasn't gone on a killing rampage.  If all that's true, it jumps to another special section of code and back. That code is complex and loads stuff. Well, you fire up the game, go to that place at that time and watch what happens. Turns out Woody Allen makes a cameo.   OR WHATEVER.

Reverse engineering looks at the guts of the programming to find hidden details.  It's made hard by the fact that it's in a very low-level language made to be read by machines and not people.


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

[User] [Return of the King] Why did Gandalf bring Pippin when he went to ward of the Nazgul as Faramirs troops retreated from Osgiliath?

[Assistant] When Pippin used the Palantir, Sauron saw him and, since the last he knew, that Palantir belonged to Saruman, Sauron assumed Saruman had captured the Hobbits and the Ring and and was planning to use it against him. Gandalf brought Pippin with him so he could personally keep him safe and out of the hands of the Nazgul or worse.


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

[User]
Admitted to JD-PhD good idea?

Hi all! Looking for different perspectives and advice.

Was recently admitted to a joint JD-PhD in philosophy at the University of Michigan. I was fortunate enough to receive full funding from both the law school and the philosophy department. So, fully funded for 6 years, and could likely get both degrees in those 6 years.

The law school is being flexible about my start date, so I could essentially order the two degrees however I would like (for ex., could do the first 2 years in the PhD, next 3 in law, final in PhD, or any other combination)

Career goals:
Ideally, I would love an academic career (though I do have doubts about my ability to succeed!). I would be happy to teach philosophy in a law school, or applied ethics and some legal philosophy in a philosophy department. So long as I am doing some philosophy, I will be happy.

That said, I appreciate the idea of having a JD as a backup in case academia does not work out (I recognize the market is tough).

My questions are these: is a joint degree a good idea? If so, how should I go about structuring it? Should I be publishing in law journals, philosophy journals, or both? How would a law school view a joint degree? How would a philosophy department view a joint degree? How can I best ensure good employment outcomes? Any other things I am not considering?

I will also note that I was accepted to Harvard Law School. That is another option I am considering.

[Assistant]
Yes a joint degree is an excellent idea if you value research and publishing. It will set you up with good options academically and in law. You should try to publish anywhere and everywhere, but if you're trying to be an academic then target crossover journals that deal with both philosophy and law.

On the other hand, Harvard Law is hard to turn down and will probably guarantee employment in law.

Either way, congrats!! These are huge accomplishments!


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

[User] ELI5 : why is there a tower with a burning flame at the top of it in every petrol plant ?

[Assistant]
Usually when oil is extracted, there comes with it a crapload of water and natural gas. The fluids go into a vessel called a separator which, you guessed it, separates the oil, water and gas.

The water is taken aside and usually pumped back into the ground or purified and used for other purposes. The oil heads to a fractional distillation column. The gas that is left behind is usually not pure enough to make it worth purifying, compressing and storing/selling. So what do you do with all this flammable-but-not-pure natural gas?

In some plants they use it to feed the boilers that power the plant itself or provide other functions. But sometimes they cant do this or the amount of gas produced is just so high that the boilers cant use it all. In those cases, the most economical thing to do is to just burn it. As pointed out before, the carbon dioxide has a lower impact on the environment than the methane otherwise would.


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

[User]
[Star Wars] I'm a clinical sociopath who was just inducted into the Jedi order. How long before they kick me out?

I was taken in at five.

I'm manipulative, cunning, and promiscuous. While I don't kill for no reason I can take lives for incredibly petty things. On that note, pets have a tendency to go missing when I'm around; and I'll happy commit any crime if I gain something or if I think I can get away with it.

How long for the Jedi to kick me out?

[Assistant]
They try to fix you for a short period of time, then finally decide you are irredeemable and send you elsewhere where you can't use the force to hurt anyone.  They have facilities for this.  Given your desire to hurt animals, they put you someplace where there is nothing for you to really hurt where you can live out the rest of your days getting really bored.

You start off as a youngling.  End.


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

[User] ELI5: Why wont your body allow you to do things like hold your breath too long, but you can ingest enough alcohol to poison yourself or overeat?

[Assistant]
Overeating is a very new concept.  Until recently, there was not a constant surplus of food for most people.   Your body wants you to overeat, because it expects there to be a famine or food shortage at any moment.

Your body will stop you from drinking too much alcohol if it can - that is why you start to vomit.   The problem is that when you drink, it has to go down your throat and into your stomach, then into your small intestine and be absorbed into your blood.   By the time your body knows there is a problem, you might have done a dozen more shots.   This lag is what lets a person poison themselves if theyre quick on the draw.


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

[User] ELI5 Why does butane gas apear to be liquid in disposable  lighters?

[Assistant]
Because butane is liquid in the lighter.

As far as a five year old is concerned, matter has 3 states:

- Solid
- Liquid
- Gas

Now, you know from water, that if you cool liquid down, it freeze and becomes ice (solid).  If you heat water up, it becomes gas (Boils).  So, we all know that temperature impacts the state of matter.  What a lot of five years don't know is that pressure also effects matter.

So, if you put a gas under pressure, it will become liquid at a higher temperature than it would normal.  If you continue to keep the pressure high, and drop the temperature, it will freeze a higher temperature than you're used to.  The inner core of the earth is ~9,800 F, but is in a solid state because the pressure is SO high.

Likewise, in a vacuum (lower pressure), matter is more volatile and will become liquid or gas quicker.  Astronauts who have had accidents in low pressure chambers have reported feeling their spit boil off their tong.  It didn't get very hot in there, it just had very very low pressure.

So, inside you lighter, the pressure is higher than the air around us.  That extra pressure keeps the butane liquid at room temperature.


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

[User]
[Watchmen] how is Adrian Veidt / Ozymandias capable of literally catching a bullet fired from a gun if he has no superpowers of any kind?

Dr Manhattan I get. But hes the only one with true superhuman abilities. How is an ordinary man (albeit intelligent) able to perform such an ability?

[Assistant]
Well that really depends on how you define "superpowers".

While they may not have traditional "comic book" powers, they are also not just average people, especially Adrian. He is far, far smarter than almost anyone else, and he is peak human as well. He is faster, stronger, and more agile than practically everyone.

The moment that gun was fired, he knew what he had to do and how to position himself to avoid it. He probably had already knew ahead of time that someone would have tried to shoot him, so he was prepared (which we find out later, he was)


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

[User]
ELI5- How was sword fighting an efficent way of combat in the old days?

Meaning, how did both parties not die from wounds inflicted during the fight 90% of the time? Or did they?

My thoughts come from modern fencing where the winner is the first one to touch the opponent (at least in epee) but is almost always still hit by the opponent.

Also the saying I've heard about knife fights, that the loser dies on the street, and the winner dies in the hospital.

[Assistant]
It wasn't efficient, and AFAIK was never a primary means of combat in warfare. Swords and knives were the last ditch you used when you were too close in with the enemy to use anything else, or when you ran out of other weapons. The most popular weapons in history were probably some form of projectile such as a throwing spear, javelin, and bow along with the spears and halberds for non-ranged combat. Even famously sword-oriented warriors such as the samurai were first and foremost, bowmen.

If you look at something like a Roman formation, they started with pilum (throwing spears), used pikes and spears between shield lines, and finally closed in and finished things up with the gladius (sword).

The major historical exception to this occurs in the context of duels, which in fact often did lead to both parties being killed or maimed. Fencing for example, isn't a sport derived from warfare, but the tradition of Western European dueling.


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

[User]
[Star Wars] Why is Cassian Andor, a Rebel Intelligence officer, such a bad liar?

In the novel they even imply he's been undercover at some time, as he knew exactly how to wear an Imperial Officer uniform. But he clearly gets nervous when he heads to assassinate Galen and Jyn wants to go with him, and then again when Jyn confronts him about wanting to kill her father.

[Assistant]
Everything he has done so far, has been on his moral beliefs of being for the greater good.

Assasinating Galen put him in a dilema, as he sees it could however harm the greater good, but he had orders.

Throw in someone bringing the human out of him, he was experiencing a Personal Crisis.


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

[User]
[Captain Marvel] Why didn't Captain Marvel do anything about Thanos before the events of Infinity War?

If you have seen Endgame, you will know that the reason why Captain Marvel hasn't been helping the Avengers is because "other planets don't have the Avengers."

Well, if she has been out helping other planets for decades, then why hasn't she heard about Thanos and attempted to stop him?  I mean, here is this strong, super intelligent being who's goal is to wipe out half of the universe, and he has been succeeding in that through the use of a near unstoppable army who's main purpose to quickly and efficiently wipe out half of the population of a planet.

Now, knowing what we know about MCU Thanos, we know that, chances are, he wouldn't just use his army once on 1 planet and say "wow, this is taking too long.  I'm just gonna wait until I have the Infinity Stones," so he has more than likely wiped out half of potentially hundred's of planet's populations, and yet Captain Marvel hasn't done anything about it?

Has there been any statement as to why Captain Marvel in the MCU hasn't done anything about Thanos?  Is there even an explanation in the comics for it?

[Assistant]
There are billions upon billions of galaxies in the universe.

Thor, an Asgardian charged with protecting the Nine Realms, had never heard of the Chitauri.  Dr. Strange, whose job it is to monitor threats, didn't know about Thanos.

Space is **big**.


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

[User]
[Star Wars] Was there a funeral service for Palpatine?

I mean, I doubt all of the empire just up and went "Well, boss is dead time to move on." right when Palpatine died.

So were there any members of The Empire who had the decency to give their boss a proper send off?

[Assistant]
[](/sombraoh)He ruled over countless trillions, and most of whom believed he was a pretty swell guy.

I guarantee you there were days of mourning, speeches to his honor, and considerable backlash against the terrorists who killed him along with countless millions of Imperial soldiers in their surprise strike.


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

[User]
[Avatar:TLA/Avatar:LOK] Nutrition wise how much energy does the various types of bending use?

Iirc bending is not treated as magic, it comes from the benders bodies and can even >!spoiler Be cut off from the users bodies by constricting bloodflow!< So what is the energy cose of bending? Would a intense bendong fight burn callories like one in martial arts or a full session in the gym?

[Assistant]
In LoK, we see that pro benders get tired out during rounds, and throughout each series, we see that bending causes physical strain on the body, but it doesn't seem proportionate to energy consumption. For instance, tiny little 12 year old Toph can hold up an entire massive library to keep it from sinking in the sand, but during a 2 minute round of a pro bending match, top athletes get too tired to fling a water whip anymore. Theres also the case of the first blood bender being able to control a guard using one of the most difficult bending techniques while she was in incredibly poor health.

Bending is not about nutritional energy consumption like muscles in the body. It's about chi and spiritual energy. It doesn't seem to be a straight 1:1 ratio. And bloodbending being used to block bending seems to be more about blocking the flow of chi through the chakras. The spiritual energy for bending flows through the body along certain paths, and can be blocked by manipulating the body, but it isn't depended on physical stamina and nutrition. After all, the best earthbender of all time was a 3 foot tall, 12 year old blind girl, not a jacked dude in great condition.

Also, if bending relied on caloric intake, then we probably would see benders scarfing down food the second a big fight ended, or carb loading before a big probending match.


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

[User] ELI5: How come certain plant species and animals, etc can reproduce asexually with no issues developing in the offspring, but when creatures like us reproduce sexually, inbreeding with someone close to us results in lots of health issues and deformity?

[Assistant]
First, the dangers of inbreeding is greatly overstated.  For most of human history we lived in small tribes and villages and... you know.  You have to inbreed consistently for many generations to see a real problem.

Species that clone themselves *do* have this problem, and it's precisely why reproductive solutions that recombine DNA evolved in the first place.  When the entire population is clones, you risk excessive propagation of genetic defects and have a severe risk of infectious attack decimating the species.

But, it's also super easy so some species opt to live with the risk and just brute force their way through with a gazillion clones.


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

[User]
[The Witcher] Why do Geralt and other Witchers bother carrying two swords: one steel sword (for humans and beasts) and one silver sword (for monsters), when one silver sword would surely be okay?

If the aim of slaying humans and beasts with a sword is to maim them, why would using the same silver sword not suffice? It's still damaging physically, and you can still apply oils and poisons as you wish. I see no point if the steel sword existing if you already have a sword that's able to kill monsters more effectively

TLDR: Silver swords would still fuck up humans, so why bother lugging around a steel sword?

Edit: it's been answered, thanks!

[Assistant]
Right, so, this is a misconception about Witcher Lore based on the games, in the books and maybe the show it's different (I haven't watched season 2 yet, so no spoilers please).

The Witchers tend to use their steel swords against almost everything, the silver sword in itself is not actually used against that many monsters, only ones that are explicitly only really weak to silver, and the Witcher needs the extra edge against them, the steel sword works fine against almost everything else.

Most monsters ARE weak to silver, but, in general, like in reality, silver is expensive, and not that durable, they don't like "wasting" the silver sword on "basic" monsters when steel will cut them up just fine.


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

[User] ELI5: The science of saline - why can we drink pure water, but when we put water into our bodies in other ways, like an IV, must we add minerals to it?

[Assistant] Your blood has a salinity concentration of about 0.9%, this is why most IV fluids have a similar salt concentration. If you were to hypothetically flood someone with pure water through an IV, it would offset the natural gradient of 0.9% causing fluid to flow into your cells and cause extreme swelling.


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

[User] ELI5: How can humans go to bed hungry but wake up feeling completely full?

[Assistant]
The feeling of being hungry is only partly related to the need for food. Feeling hungry is a sign a particular hormone is realeased. This hormone is released when you lack nutrients, sure (if your blood sugar levels are too low, for example), but mainly, it is released when your body expect some food to arrive soon, and is ready for digestion. So if you take your meals at regular times, and one day you skip one, about 30 minutes after your usual intake of food, you should feel very hungry. Because your body did not receive the food it was expecting.

But a few hours later, the levels of that hormone are down again (it's way past the time were food was expected), so you don't feel hungry. And you'll probably feel hungry again just before your next usual meal.

A very remarkable consequence of this is what happens when people do not eat anything for several days. The first two days, they'll feel very hungry. But after that, hunger disappears. At the opposite, people who would eat extremely little would still feel hunger for much longer, even though they get more food.


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

[User]
Why can't all countries have the same currency?

I mean other than prestige and uniqueness, what's the point of having different currencies?

[Assistant]
This comes down to what is known as optimal currency areas (or optimal currency union). One main issue is you can't have regionally different monetary policies under a single currency. Consider the US and EuroZone, there 1 monetary policy. A  key characteristics of a optimal currency area are the same exposure and response to shocks. That is if one area is in expansion all the others are as well. The mobility of labor and capital are also important qualities. Suppose you have a region on recession and one in expansion what should the central bank do? Expansionary policy for the recessed region? Restrictive policy to slow the growth in the growing region?

One way to account for this is a fiscal union. This is one reason the US is considered an optimal currency area and the Euro isn't. The US federal government can use fiscal policy to balance out the regional differences, where the EU has less ability to do so. So absent a world fiscal union having one world currency would not be a good idea.


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

[User]
Does surviving a viral infection always result in immunity?

Let's take ebola, for example.  I've ready that it has about a 10% survival rate.  Do those survivors become immune for life, or can they get re-infected and suffer symptoms again?

[Assistant]
Plain and simple: No. There is no 100% secure immunity when it comes to infections or infectious diseases.

Take the EBV (infectious mononucleosis). Years ago the credo was that if once gone though a mononucleosis, you're safe for at least 25 years. Today we know, that there's a high probability that you'll never catch it again after being infected once, some time in your life. But there are documented cases where patients with no other conditions or any immune suppressive circumstances (like medication or other illness) catched it again and went through another cycle of infectious mononucleosis.

Also, there are virus infections like herpes. It's just not curable. It's treatable, but once the current infection has been "defeated" the virus itself persists in tbe body, just to wait for another opportunity to become active again and give you another hard time, another active infection.


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

[User]
What happens when a bruise heals?

I understand that bruises are formed by small amounts of blood being released into the tissue beneath the skin, but where does that blood go as the bruise fades?

[Assistant] The short answer is that a number of cells are recruited to eat and otherwise break down the debris, especially the erythrocytes, which are ultimately either recycled in part or excreted as waste after processing in the liver/spleen. In particular the eating is carried out by leukocytes which are recruited to the area via the inflammatory process. Depending on severity and location of the bruise there might be some residual staining from the liberated iron, but that will usually also fade with time in a healthy person.


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

[User] If the Higgs field gives mass to matter, and the mass of matter curves spacetime, and said curvature is the basis of gravity; does this imply that the Higgs field causes gravity?

[Assistant]
Here the distinction between two types of mass becomes important. Theres inertial mass, which is the m in Newtons F=ma. It takes effort to make something with nonzero inertial mass move. In contrast, something with zero inertial mass, such as photons, must always move at the speed of light. We know that electrons and quarks (which make up neutrons and protons) dont move at the speed of light, so they must have nonzero inertial mass. The Higgs boson is what gives them this inertial mass.

On the other hand, theres gravitational mass, which is what makes things gravitate towards each other. Incidentally, this is exactly equal to the inertial mass in Newtons theory of motion and gravitation. In Einsteins updated theory (general relativity), this equivalence between inertial and gravitational mass is so central that it has a name, the equivalence principle. However, Einstein extended the definition of this mass to include all forms of energy, so even massless things like light can now gravitationally attract other things. You dont need inertial mass to have gravity, according to Einstein, so quarks and electrons would gravitate even without the Higgs boson (though it certainly helps).

In the Standard Model of Particle Physics, we included all the known fundamental particles and interactions between them (photons, electrons, quarks, Higgs boson, etc), with the exception of gravity. If we try to include it, then every single particle (with or without inertial mass) will interact with the graviton and lead to gravitation, in a way consistent with Einsteins generalised mass-energy. However, doing so happens to cause the whole quantum field theory (the mathematics framework of the Standard Model) to utterly break down, so we have not yet understood the precise relation between the Higgs boson (which can only be explained through quantum field theory) and gravity.


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

[User]
CMV: Illegal immigration in the USA would be far less common if there were strict penalties for employing illegal immigrants. However, this won't happen because of intense lobbying

From my knowledge and perspective, most policies aimed at curbing illegal immigration are aimed at the illegal immigrants. You even frequently hear the comment: "they are breaking the law" or "they need to follow the laws of this country". However, illegal immigrants have very little motivation to follow immigration law. If they follow the immigration law, they are denied entry into the USA and gain no benefit. If they violate the law, they gain better pay and only risk being caught and possibly deported. There is little risk and a great deal of reward. You would be a fool to just "follow the US law"

Employers, on the other hand, actually have some reason to not employ illegal immigrants(see below). However, the benefit is only seen if everyone(or mostly everyone) is following the law. The current enforcement regime seems to strongly encourage businesses to cheat. Many small business owners I know employ illegal immigrants. Now, they don't knowingly hire illegal immigrants, but they are well aware that many of their employees are probably illegal immigrants. They know that the social security numbers they were given are probably fake, but as long as they run them through the government required website, they feel that they are clear of any consequences. However, these people will admit that they employ illegal immigrants.

*Example of strict law enforcement for suppliers: Alcohol sales*

Most states do not worry about underage buyers of alcohol. Rather, they focus on alcohol retailers and have strict fines and penalties for any supplier caught selling or providing alcohol to a minor. While minors still get access to alcohol, it is nearly impossible to find a minor drinking at a bar or buying liquor at a liquor store. In fact, many liquor stores/bars will deny sales to individuals who are not minors out of an abundance of caution.
I am not saying that no minor ever buys alcohol with a fake ID, but I would say that there are far fewer minors buying alcohol than illegal immigrants working at large corporations. Why? Because bars/restaurants/stores suffer a severe penalty if they are caught violating the law.

Please change my view.

**Most laws benefit everyone in society(my argument explained)**

Most laws actually benefit everyone. The law against theft actually benefits everyone eventually. If theft was legal, no one would benefit. A thief might temporarily gain some money by stealing your car, but then he would immediately lose it when the car was stolen from him along with his other property.

If hiring illegal immigrants was totally illegal, the companies would actually be fine. They might need to raise their prices, but they would also know that all of their competitors would also need to raise their prices as well.

[Assistant]
To go somewhat orthogonal to your suggestion, wouldn't it be more reasonable to simply allow those people to immigrate legally? Your view posits that there is are industries that are built on exploitation of underpaid labor, and additional industries built on providing false social security numbers. It seems like allowing people to *legally* immigrate to the United States for the purpose of performing those jobs would serve to limit the exploitation, especially since as legal residents they would be better able to report any further exploitation by their employers.

Now, you could combine that with more penalties for exploitative labor practices or hiring under the table, but that doesn't solve the issue that those industries (apparently) cannot find enough labor without turning to immigrants.


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

[User] Why, as time goes on, do video players on the internet seem to be getting worse instead of better?

[Assistant]
For some reason, the people responding to you seem to think you said "video game players", when you actually said "video players".

And video players are *not* getting worse.  Do you remember RealPlayer?  The whole "buffering..." thing was a running gag for *years*.


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

[User]
[Devils] Is it just me, or does it seem like almost every deal with a Devil is not worth it?

They're always either incredibly one sided, made in bad faith by the devil in question, or otherwise generally unappealing. Its rare for you to see a deal with a devil that is genuinely mutually beneficial.

How do devils expect people to make deals with them when the deals are so often shitty or betrayed? Sure, its a devil, but good faith is important to any transaction, even if its with a being of pure evil!

[Assistant]
Why do people sign up for extended warranties?

Humans are irrational, ill informed, desperate, and/or think they're smarter than everyone else.  Demonic beings know this and so don't generally need to sweeten the bad deals they make.  They can afford to continue running things as they are.


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

[User]
I am an antinatalist. (i.e. I believe that having children is unethical.) CMV

**Please read the entirety of my post before commenting. Thank you.**

I'm here today on CMV because I hold a belief that is not only so uncommon to the point of being practically unheard of, but is borderline taboo. I feel as if my belief is based on well founded ideas of ethics, and follows objective reasoning, and therefore, is correct. And yet, here I stand against a world of academics and thinkers, most of which do not adopt antinatalist viewpoints. I'm not here to understand why they think it - biology, sociology, and religion all give compelling answers as to *why* they think it. Why *I* think it, (as in, how I came across it and haven't recoiled in horror,) is also off topic. I'm just here today to discuss the topic of antinatalism, and that's all.

Okay, here is my logic. If you find a problem with any step or missing information, please point it out so that we can get on with this debate as quickly and efficiently as possible.

~~1. Moral actions are actions that, regardless of physical consequences to one's self, are things that ought to be done.
2. Immoral actions are actions that, regardless of physical consequences to one's self, are things that ought not to be done.
3. Doing harm to someone else, and having them acknowledge/react to the harm, is always immoral.
4. Incurring pleasure to someone else, and having them acknowledge/react to the pleasure, is always moral.
5. Doing harm to and incurring pleasure upon someone else is only moral if the net outcome in the recipient's mind is positive. Otherwise, it is immoral.
6. Acting on consent voids the morality of an action, *if and only if the person giving consent is capable of rational decisions, and is 100% certain of the outcomes.* (Under this rule, a person giving consent would never regret doing so. Otherwise, he or she was not entirely informed of the consequences.)
7. When you bring together a sperm and egg to create a new human, (i.e. Have a child,) you are bringing both harm and pleasure to the new human, as he or she would not have experienced either otherwise.
8. An unborn child is unable to give consent to his or her creation.
9. You can never know how the life of a child will turn out.
10. A risk taken for someone else (without consent) that could incur harm or pleasure is immoral.
11. Because of (8), (9), and (10), creating a life is immoral.
12. Because of (11) and (2), having children ought not to be done. I am perfectly fine with societal consequences of this, and feel as if our inevitable demise is better if voluntary and under our control, as opposed to violent and horrid as it probably will be.~~

**The premises were flawed, but also unnecessary, okay? Just read the paragraph below.**

And now for the sloppy version:

Having a child incurs pain and pleasure to an otherwise non-feeling, non-existent person. By doing so, you are taking a risk as to whether or not they will experience more pleasure or more pain, and whether or not they will wish to undo their life. Undoing their life, (or ruing their creation,) indicates that they have been harmed, and as a result, the action was immoral. You may argue that only a small percent of people actually feel harmed by their existence. Other antinatalists step in here and try and prove that we ALL suffer enough to OBJECTIVELY prove that our lives were not worth being created. I take a different approach - I say that you are taking a greater-than-negligible risk for someone else. The only saving grace could be consent, but as that is impossible to obtain, childbirth is immoral.

Alright, I hope I explained myself well enough. Please don't comment along the lines of "why don't you kill yourself then?". Yes, I've received this type of reply before.

Thoughts?

EDIT: Okay, my axioms are a bit flawed, but a few of them are also a bit unnecessary. Just pay attention to my paragraph at the end, then. I think my logic is solid there.

EDIT 2: Thanks for all your replies - I'm having much fun replying to them. However, I need to get to bed - I'll be back tomorrow!

EDIT 3: I'm sorry everyone, but it's becoming daunting and quite time consuming to keep up with the replies. I feel I've responded to the lot of incoming comments anyway. I'll check back later.

EDIT 4: Okay everyone, thanks for your replies. I changed my view away from the risk argument, and back towards something more like the asymmetry argument. I'll still be checking my mail box for new replies, but chances are I won't be replying to all of them unless something particularly strikes me. Have a great day all you breeders!

[Assistant]
You really think that your moral view is sensible if it causes the absolute eradication of the human race.

Also, have you heard of implied consent. It makes a lot more since than 3.

As far as 6 goes, is anyone ever 100% sure of the consequences?


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

[User] ELI5: Do police dogs get "paid" in any way?

[Assistant] They get food. They get a nice place to stay. They get their medical bills covered. They get their education paid for. Dogs don't understand the concept of money, but they have a pretty good life compared to a lot of dogs.


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

[User]
ELI5: I have a "voice in my head", think and dream concepts with language. What is a deaf person's inner monologue like?

The radiolab explanation hasn't quite cut it for me.  Thanks smart people of Reddit!

[Assistant] I have two deaf brothers. They tell me that thinking is like hearing muffled thuds in the brain and their inner thoughts are more visually oriented than sound oriented. They have a visual for each word.


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

[User] ELI5: Why can different parts of the human body withstand different amounts of pain?

[Assistant]
Some parts are more important and exposed (ie: eyes, hands, feet, groin) and so they need to be protected more, and the easiest way to do that is to make it feel bad when something damages them, so that you avoid that happening.

Other parts are already very well protected by bones and muscle (brain, heart, most internal organs) so they don't usually get damaged from outside stuff, and that means they don't need to tell you as quickly. This actually causes problems, such as when people get tumors or other growths, and don't notice it until it starts damaging everything around it and making things too cramped in there.


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

[User] ELI5: If Australia is so dangerous how did such a small number of rabbits breed so much so quickly?

[Assistant]
That's what rabbits do, everywhere. It's kind of their thing. They breed like .... rabbits. The are generally considered a pest in most places wherever they exist, though not to the levels of ecological menace that they are in Australia.

Their success in Australia is attributed to lack of natural predators, evolving into a particularly hardy breed, and mild winters that allow them to essentially breed year-round.


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

[User] Eli5: why do 220v circuits not need a neutral?

[Assistant]
Circuits need a return path. In a normal circuit one uses  a hot leg that swings to the max positive and negative voltage and a neutral that is nominally at 0 volts. This is partly because it means you only have 1 leg that has potentially dangerous voltage on it.

For 220, instead of using a neutral as a return path, we use another hot leg that has opposite phase. The reason for this is because we can get twice the voltage and it's easy to generate this second hot opposite phase leg with a transformer.  The trade off is that now we have two hots that have potentially dangerous voltage on them. However a safety ground is still used so steps are taken to minimize the risks.


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

[User]
Does a freshly hatched chicken have the exact same nutritional content as an unfertilized egg?

I know, a very strange question and no I don't plan on eating any chicks. It seems like a chick should have more calories, protein and a variety of other vitamins. But it can only develop from the same stuff that's in the unfertilized egg so it should be nutritionally equal?

[Assistant] While it is true that a chick grows from what is provided in the egg, to say they are nutritionally the same is like saying that a pile of building materials is the same as a house. The chick will be much more complex than the original contents of the egg. There will be much more nucleic acid, protein and a lot less fat and carbohydrates. The reason this can happen is that living things can create complex organic molecules out of simpler ones, such as those provided in the egg.


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

[User]
[Marvel & DC] Who's the most evil character who could still be considered a super hero?

And the most good supervillain.

[Assistant]
For DC, John Constantine is perfectly willing to take advantage of people to the point of getting them killed (or leaving them traumatized) if the other option is to let the villain get away with unspeakable evil. Swamp Thing hates him just because Constantine thinks it's perfectly fine to practically enslave him for the purpose of saving humanity, as Swamp Thing isn't really concerned about humans while Constantine considers using a high-powered elemental entity to save people more important than Swampy's freedom.

As for villains, Mr Freeze just wants a normal life for him and his wife. He'd be a perfectly good person if someone could just cure the both of them. Lex Luthor has also contributed to the world's advancement quite well, albeit in the process of developing some insane projects for no reason other than to kill aliens regardless of how peaceful they are. He also contributes to saving the world on occasion.


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

[User] [Barbie] Would Barbie's Dream House be affected by the housing crisis?

[Assistant] No. Barbie works dozens of jobs, from teacher to computer game progammer, to doctor, to astronaut. While she does have a habit of spending a ton of money on clothes and has recently begun doing cosplay too, she still makes enough money from her dozens of jobs to cover the rising mortgage on her Dream House, and keep Ken around, despite the lazy bum not having a job.


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

[User] I've recently heard about people who identify as "spiritual but not religious." Is there a philosophical sense to this (in essence, philosophers who would hold such a stance), and if so are there philosophers who identify as "religious but not spiritual."

[Assistant]
This seems better suited for social scientists on the clarity of defintions in surveys but, to take a stab at it, 'religious' might imply a sense of organization around belief or dogma; whereas 'spiritual' can just mean having a sense of enchantment or enthusiasm.

In general I'd say philosophers tend to describe 'spiritual'as not necessarily religious for example, Charles Taylor describes 'spiritual' as meaning ethics in the most broad sense in *Sources of the Self*.


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

[User]
[MCU] Hey you know what this sub needs? Another Mjolnir thread. [Age of Ultron spoilers]

Given the new information of who can and can't wield the hammer, what do we now think makes someone "worthy"?

And what about that elevator?

[Assistant]
Mjolnir is less about worthiness than the movie makes out - It is still a factor, but there are others.

Mjolnir is about *intent*. What you plan on doing with it. Sure, Cap would be worthy of it normally, but picking it up to show off? Not so much.

There are plenty of recorded instances of Mjolnir being used by just about all of the avengers from one time to another, and at least one instance of it being used by a random-ass paramedic.


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

[User]
CMV: The media and justice system should not disclose the names of criminal suspects until they have been found guilty at trial.

It seems that in recent years, people have faced repercussions and backlash in their lives for mere suspicion of criminal activity. Names like Johnny Depp, who was all but crucified in the media and lost a prominent film role, on only the accusation of being abusive, seem to be becoming more prominent.

It seems to me that were it forbidden to divulge the identity of suspects, directly or indirectly, wed have a lot less damage being done through the Court of Public Opinion, and less lives being ruined through preemptive punitive action from scared colleagues or employers.

[Assistant]
Australian courts make heavy use of this kind of tactic, but quickly ran into a problem. They  commonly ordered press bans on names of those charged domestically, but  could not prohibit foreign journalists publishing them. Any Australian with an internet connection could find the names anyways.

So let's say criminal charges are brought against Johnny Depp in the US, all an American has to do is go to a Canadian news site to see what famous celebrity was arrested.

If the courts themselves don't publish names, then you get scary stuff like secret trials, not good for a democracy.


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

[User]
ELI5: Transgender, transsexual, transvestite

My friends and I couldn't figure out a definition of each, and when we looked it up it seemed very vague and perplexing. Please explain like I am 5 the difference between them.

[Assistant]
Someone with a boy body and a boy brain who dresses like a girl when he feels like it is a transvestite. People will dress up like another gender for all sorts of reasons even if they don't think of themselves as that gender. Some do it for fun or sexual kinks, like Dr. Frank N Furter from *The Rocky Horror Picture Show*, and some do it for social purpose, like Mulan dressing up as a man to go to war instead of her father.

Someone with a boy body but a girl brain is transsexual, because they don't match. Sometimes these people go to the doctor so they can have a girl body for their girl brain. This has much more to do with 'gender identity' than it has to do with what someone dresses as, and usually has a heavy implication of physical sex changes.

Transsexuals and transvestites are both transgender the same way red cars and blue cars are both still cars.


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

[User]
ELI5: Why are we so fixated on finding water on other planets, as a sign of life? Is it not possible that other life forms would function without water as we know it?

I just find that we are constantly seeking water when we discover other planets, because it would imply that the planet could sustain life. Is this just us saying it could sustain our lives?

I just think it a bit myopic to believe that the only life out there must require water for survival.

[Assistant]
It's *possible*, but life probably needs some liquid medium to do chemistry in and water is by far the most common and convenient.

Some planets likely have seas of other liquids like methane and ethane (Like Saturn's moon Titan) but these liquids present some problems that may be difficult for complex biochemistry to solve.

Water also gets the top spot because we have to look for something.  We would have no idea how to start looking for the bio signatures of rock men with lava blood.


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

[User] [Cabin in the Woods] What are the rules for other countries sacrifices?

[Assistant] I imagine it'd follow the horror movie conventions of the respective countries. The brief clips we see of the Japanese operation show a very Sadako-esque ghost girl typical of Japanese horror. Since she's shown attacking a group of little girls they're probably not following the same Whore-Athlete-Scholar-Fool-Virgin pattern. Maybe there are multiple Ancient Ones, each demanding a different ceremony be performed to sate them.


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

[User]
ELI5:Why does it get greenish outside when a tornado is coming?

I've lived in Kansas for most of my life and it was just accepted that if outside had a green/ yellow tint that was a sign of a tornado. What causes this, and is it actually indicative of a tornado?

[Assistant] "Researchers remain undecided about the exact mechanisms that cause the sky to appear green in certain thunderstorms, but most point to the liquid water content in the air. The moisture particles are so small that they can bend the light and alter its appearance to the observer. These water droplets absorb red light, making the scattered light appear blue. If this blue scattered light is set against an environment heavy in red lightduring sunset for instanceand a dark gray thunderstorm cloud, the net effect can make the sky appear faintly green. In fact, green thunderstorms are most commonly reported in the late afternoon and evening"


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

[User] ELI5 why do so many people hate Obama? The economy is back up and unemployment is down? What has he done wrong?

[Assistant]
I think you can basically chalk it up to "spin".

The republicans and democrats are locked in a never-ending struggle for political power.   Regardless of what's true or sensible, they'll both take any opportunity to make the other team look bad.

For some reason, most private citizens and media outlets also buy into this game, and will go along with the attempts to make the other team look bad.

So, (it bears mentioning that it was similar in the Bush Jr. years), party loyalists will always say the other team's president is the absolute worst, literally hitler, trying to throw people in prison camps, etc.  This is regardless of the fact that the sitting president's record is usually pretty mixed, with some successes and some failures.

More specifically about the economy, the stock market is up, GDP is up, employment is up, but wages are pointedly NOT up unless you're rich.  So basically people are working their asses off for the same or less money, and healthcare is getting more expensive every year.  So, the vast majority people really do have a reason to be unhappy with the economy, because the upturn isn't helping them much or at all.

Now, whether this is actually obama's fault, the Fed's or congress' (it's all 3 in various ways) is not important, what's important is for the GOP to shit all over Obama as often as possible, to score points in the political game.  So that's basically why you see all the Obama hate.

Also, some racism, but that's probably less dominant than the other factors above.  Obama being black is just one tool in the GOP toolbox of making the other team look bad.  It's very effective with certain people.


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

[User]
How does an entire power grid fail, as in India right now or in the US and Canada in 2003?

I was wondering what exactly causes the failure of an entire power grid, and why fixing it is not as simple as selectively switching off parts of the grid and hooking them up again iteratively. Are there pieces of equipment that are destroyed in the process?

[Assistant]
Nuclear engineer here (I work in a power plant).

There is a lot of talk about cascading failures. To understand why they are such an issue, you need to remember two things. First, heat generated in lines, transformers, breakers, is proportional to current drawn, and second, there is a very strict balance between how much "Load" is on the grid (how much power draw there is) and how much power is being generated on the grid. This balance is both in terms of VARs (imaginary power units) as well as VA (Volt-Amp, Apparent Power).

So to better understand this, imagine the following situation. You have very little available electrical margin on your grid. Something happens (say a tree hits a line) and causes a fault on a cross connect between two regional areas. This line disconnects the two regions. One region had more power available than load, and the other region had more load than available generation. On region 1, the power stations will runback due to the load reject. If the load reject is severe enough, the power transient will cause the generator to go into a load reject trip to protect itself from the power transients on the grid. This would cause power stations on grid 1 to fail. These stations going down will cause the loads on grid 1 to pull in power from anywhere they can. Say they pull power in from another regional line, but that line now becomes overloaded. Overloading the line causes increased temperatures and leads to failures. These failures can cause other parts of the grid to become unbalanced, and so-on and so-forth. A well designed grid protection system will be able to detect this and stop it from crossing from major regions, but that's not always the case.

The real simple answer is you throw that load balance off, and when power margins are tight to begin with, the grid cannot handle that very well.

As for why you can't "just fix it". Firstly, big power plants will need to go through their cooldown/heatup cycles. There may be damage caused as a result of the sudden load reject. In the case of nuclear power plants, there are very few plants that can handle a full load reject without a reactor scram, and recovering from a scram usually takes a few days to do equipment inspections and the like. Field equipment like lines, transformers, and switchgear, all need to be inspected and repaired. Finally, when the grid is brought back online, you ALWAYS have to maintain a balance between power and load, and as a result, depending on how bad the outage is, you need to bring it up very slowly and in a very controlled fashion to prevent sudden load transients from putting you back into a total blackout condition.


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

[User] ELI5: If they're undocumented immigrants, how does the US know that there are 11 million of them?

[Assistant]
The US doesn't know; but it estimates.

There are many different estimates and approximations. The most cited number comes from census data. The census does not ask if someone is legally in the country or not, but it does ask about place of birth. The government does know how many foreigners are permanent residents and how many have become citizens, so subtracting the legal immigrants from the foreign-born census respondents yields the number of illegal immigrants.

This number is an estimate, and far from perfect. Not everybody responds to census, for instance, and many illegal immigrants specifically don't respond. So the number is refined by other metrics, is compared with other things known about people. Even if they are illegally in the country, they still need to pay rent, drive, work, do other things. Combining all this information with statistical analysis generates the estimate.


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

[User]
ELI5: How do games render particle effects so much faster than programs like after effects?

I understand that while games have preset effects, programs needs to calculate every particle. However the games particle effects arent the same everytime which I guess means that each particle is also calculated. How is it that a game like overwatch can calculate tens of effects more than 60 times a second while the same computer takes a minute to render a simple particle effect?

[Assistant]
Part of it is the hardware used. Every computer has two main pieces of hardware which calculate things, graphics (gpu) and central (cpu). Each are specialized in some kind of processing and have a performance advantage at it. This is like having both a sedan and a truck. While both can take you shopping, a sedan is easier to park and the truck can carry large objects better. Going to the mall may work better the sedan and going to a home improvement store may need the truck.

How programs leverage those resources is up how they are written. More recently, programs do a better job using the GPU when available and can spread the load across both accordingly, but games surely do have on average a larger focus on the GPU than other programs. It just so happens that the GPU is generally much more efficient for particle physics.

The other part is how the particles are created and calculated. Games cheat in a lot of places to make it fast, as a stuttering image is far mor noticeable and negatively impactful to the viewers experience than cutting corners in particle calculations and only having an approximate version of what should happen. Given that after effects and the like dont have this real time constraint, they can take their sweet time in getting everything just right.

A really good example of where this makes a difference is in lighting. Games will do something like hey heres the sun, its bright, and these surfaces face the sun so theyll be bright too. This is most of the way there, as in an outdoor, daytime scene, the sun is the brightest object. What it misses is that all surfaces reflect light to some degree. Mirrors obviously reflect a lot, but every object you see does too. Thats why you can see it. Calculating how bright something should be based off of not only the suns direct light, but also the faint reflections of everything around it gets to be very complicated. If you want to get it really close to accurate, that computation takes a while. If you want it to be live, you may only get to 90% accurate. After effects will start from how accurate it needs to be and work backwards for how long it will take, where the game will effectively work the other direction and set the time you have and cut corners to get something in that time frame.


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

[User] [Pokemon] Where does Professor Oak get the starter Pokmon? Is there enough for each ten year old to get to choose from all three or are they stuck with the leftovers?

[Assistant]
From his old days as a trainer himself, and no, they're finite.
Ash only got Pikachu because he was late to the lab, and it was the only Pokemon left, because it was a little shit and nobody wanted it.


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

[User]
I think depression reveals truth. CMV

I basically think that the view you get in a deep depression is true and the rest is living in a happy delusion of sorts.

When you're depressed you see the world as a empty, meaningless place and you feel insignificant and everything you used to enjoy is now just void of pleasure.
Music is just sounds. Television is just images and goals you had are just empty goal you set to fuifill a ego that is now asleep.

[Assistant]
As someone who's been there, done that: no dude, that's the crazy talking. It's exactly as credible as a schizophrenic refusing to take their meds because they think their delusions are what's real.

Depression lies to you. Here's an easy example to test - it makes you think people don't care about you. People do care about you. You can ask them. They'll tell you. Who are you going to believe: the lack of dopamine and seretonin, or the people you've known all your life? And if depression is lying about that, what makes you think it's telling the truth about everything else?

Don't listen to the crazy. Get better. See the real world, not the one that's clouded by an apathetic grey haze.


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

[User]
[Witcher] Is the Conjunction of the Spheres a one time event or is it expected to happen from time to time?

I know canonically the last event was 1500 years ago or so and not much is known... Is it possible this happens cyclically over a long time or is it one and done?

[Assistant]
It happens from time to time. Nobody knows if the Gnomes are native to the Witchers World, but Dwarves are not and arrived via a Conjunction Event. Next were the Elves who actually arrived via 'ships' during an age where such things were possible. The Humanity, and later the Vampires.

There have probably been a number of smaller conjunctions which were either not noticed or not accounted which may have been responsible for things like Succubi, Dryads, etc.


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

[User]
Why do we even have computer viruses? Is it just Tom-douchery, or is there a bigger underlining reason?

Thank you for the swift answers everyone! :)

[Assistant]
A computer virus is just a typical piece of code telling a computer to do something. The people who write viruses wants the computer to do or give them access to something that the computer owner did not intend.

You can write a virus that just makes dicks pop-up on screen to just be an asshole or you could make a virus like Stuxnet, the virus that destroyed some Iranian nuclear centrifuges.


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

[User]
ELI5:How do polaroid pictures work?

How do the pictures just slowly come in there etc?

[Assistant]
Freakin' magic, that's how!

In a nutshell, a polaroid is a little envelope that contains all the chemicals needed to develop and fix the picture.  Light hits chemicals that are sensitive to light, which react with reagents in a different layer that cause dyes to migrate into the first layer and become visible.

Developing a photograph takes time (the chemical reactions aren't instantaneous), and the first process to do instant color prints didn't work very well.  The solution was to add another layer of chemicals that opacify soon after the exposure to light.  This makes it dark inside the layers, and allows the time necessary for the developing and fixing process to happen without being exposed to more light.  That opacifier breaks down and becomes clear after a period of time.   That's what you're actually seeing when the polaroid comes out grey and image slowly shows up.


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

[User]
Why is there far more matter than antimatter in the observable universe?

I have no idea why this would be and could really use some insight. Thanks!

[Assistant]
This is an unsolved problem in physics, but there are two broad suggestions.

First is that there are in fact equal amounts, but they are kept apart somehow. However, since intergalactic space isn't quite empty, if there were galaxies/clusters/superclusters of antimatter in our observable universe, we would see a very recogniseable gamma-ray signal. This raises more questions than it answers, really.

The more likely one is that there are some physical processes that create a numerical imbalance in matter and antimatter. Ideas for these sorts of mechanisms are collectively called baryogenesis and leptogenesis. They're based on the violation of baryon number and lepton number, which are probably purely empirical conserved quantities (we assume they're conserved because we've never seen otherwise).

A key part of matter-antimatter asymmetry is CP violation: the weak force is known to treat particles and antiparticles slightly differently.


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

[User]
Every day I heat 1 cup of water in the microwave for 2m 10s. Some days it gently boils in the microwave. Other days the water remains still and then boils violently the moment I insert a kitchen thermometer. Why?

Footnote: I'm making coffee with an Aeropress.

[Assistant]
You are (sometimes) superheating the water past its normal boiling point.  This occurs because the vessel you are using to heat the water is generally free of anything that can be used to nucleate a bubble of steam.  Without these nucleation points you can go past the thermodynamic equilibrium and heat the water past the boiling point.  As soon as you disturb the superheated water or put something in it that can act as a nucleation site like the thermometer it will vigorously boil until it cools down below the normal boiling point.

To avoid this potentially dangerous phenomenon when heating water in the microwave it is always recommended to put something in that can act as a nucleation site.  A toothpick or chopstick generally works pretty well, or anything else that is not metal and has a somewhat rough surface.


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

[User]
ELI5: What is the reason radioactive decay is measured in half-lifes instead of just using the elements full-life?

Is there something special about the halfway point? Does the decay happen at a steady pace or exponentially?

[Assistant] The half-life isn't the half-way point. That is, if something has a half-life of 5 years, that doesn't mean it all decays in 10 years, it means that it takes 5 years for half the substance to decay. In the next 5 years half the remaining substance will decay, and so forth.


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

[User]
[Batman] Is the rest of The Jokers body hair green as well?

Asking for a friend, like would his chest and armpit hair be green as well or just black?

[Assistant] It would probably depend on which version of the Joker youre talking about. Some dye their hair which probably means body hair is left natural and some had their hair turn green due to chemicals which would likely include body hair.


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

[User]
In the distant future, will human garbage landfills become pockets of oil?

Fossil fuels are thought to be massive amounts of organic material that was buried long ago, and transformed by various processes into oil, coal, and natural gas.  Our landfills are mostly organic material, so will there be pockets of fossil fuels created by human concentration of garbage in the very distant future?

[Assistant]
The earth went through a phase called the carboniferous period wherein cellulose and wood lignin had evolved, but no organisms capable of metabolising it existed. Thus the plants could grow and grow and grow and lay down biomass that was effectively nonbiodegradable plastic. Nothing could eat it, nothing could process it, it just choked huge areas of the surface until it built up so thick that layers upon layers of wood and lignin compressed eachother endlessly. Most of the coal we have today came from this.

Our landfills are tiny in relative scale and dimension, and we are likely to eliminate most waste through composting and recycling long before we lay in the trillions of tons necessary to form coal.


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

[User]
What movies would you recommend for philosophical discussions?  (Examples in link.)

I like to use films in my courses.  Not only do they give us a a mini-break around exam time but let us have some fun things to talk about.  For example, I've used American History X when discussing race relations and affirmative action; A Clockwork Orange when discussing theories of punishment; The Insider when discussing whistle-blowing.  Any films you would like to use as a teacher or watch as a student?

[Assistant]
Groundhog Day: eternal recurrence of the same.

The Truman Show: epistemology, a modern interpretation of Descartes' evil demon scenario; metaphysics, determinism.

Memento: philosophy of mind / personal identity.

Shutter Island: philosophy of mind / personal identity. Similar themes as Memento and The Truman Show. Very thought-provoking psychological thriller.

No Country for Old Men: ethics, questions of human nature and evil, existentialism.

V for Vendetta: question authority, question the government; ethics, in what sense do V's ends justify his means? Works well while reading Machiavelli, Rousseau, and Jefferson. Aesthetics, art censorship.

It's great that you use A Clockwork Orange. That's definitely one of the best films to watch when discussing theories of punishment.


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

[User] ELI5: why do puppies (and some grown dogs)often tilt their heads to the side when spoken to by humans?

[Assistant] Dogs are particularly sensitive to the tiny difference in time between hearing something in each ear, and tilting their head allows them to better identify where a sound is coming from or how far away it is.


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

[User]
[Watchmen] Is Ozymandis smarter than Dr Manhattan?

Dr Manhattan might say that, while Ozymandis is the smartest man alive, he is ,nonetheless, and unlike Dr Manhattan, just a man.

But at the end of the day, Ozymandis outsmarted Dr Manhattan.

Additional Watchmen question - why not create another Dr Manhattan, by just following how he was created?

[Assistant] Dr Manhattan has an ultimate understanding of time and space. The one thing he doesn't truly understand is human nature. While Ozymandis' understanding of the universe pales in comparison to that of Dr Manhattan, his understanding of human nature allowed him to develop a plan that would beat Dr Manhattan.


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

[User]
ELI5 If high blood pressure is caused by your heart overworking itself, why does exercise which force your heart to work harder lower blood pressure?

**EDIT** ADDING INFORMATION

Thank you all so much for the responses. I learned alot and got more clarity about blood pressure. I'm 32 years old with Ortho-Hypertension (one doc told me). I seen multiple cardiologists, pulmonologists, PcPs, and neurologist and gotten plenty of CTs, MRIs of almost every part of my body, multiple stress and echos., and all types of blood work. My blood pressure at rest could get as low as 120 or as high as 140/80 but slight movement would cause it to jump to 160-180/105. I take 2 medications on for but I had a ton of allergic reactions to them so it's hard to dial in on what I can take and what's causing the issue. While I do exercise I think I will put more time into it, I was just concerned that putting more work would cause it to climb. Thank you all sooo much!! Wish I could express my gratitude as I been fighting this situation for the past 5 years.

[Assistant]
High blood pressure is more complicated than that. You might think of blood pressure like body temperature, where there's a set point that your body is trying to keep. We want enough pressure that every organ gets good blood flow (especially your brain, since you have to pump straight against gravity to get from heart to brain) but not so much that we over-stress the system or burst a vessel.

 A lot of things go into what your blood pressure is at any moment, and all are regulated different ways:

\*How much volume is in your arteries and veins. From a pressure point of view, blood is basically saltwater. Plenty of salt and water live other places in the body, so this can vary more than you'd think.

\*How blood is being pumped. The heart can vary both its rate and how hard it pumps.

\*How hard arteries are pushing back. Arteries aren't just dumb tubes like the plumbing in a house. They're lined with smooth muscle which can relax or contract, decreasing or increasing pressure.

Chronic high blood pressure is what we worry about. Because the body is normally so good at regulating blood pressure, having chronic high blood pressure generally means that slow processes over time have altered that set point. This can involve changes in the stress response system, the kidney systems that regulate salt/water volume, changes in the lining of the blood vessels, and changes in the heart. Exactly why high blood pressure happens is a huge area of research and gets really complicated (and a little controversial, especially when we talk about salt in the diet.) We do know that regular exercise is part of keeping that healthy regulation of blood pressure normal.

Exercise can indeed briefly raise blood pressure (for accurate blood pressure measurement, we like to have people sit quietly for five minutes.) But our goal isn't to bring down blood pressure immediately. We want to slowly bring it down over time and keep it down. Exercise has positive effects on the heart, the blood vessels, the brain, the stress response system, and much more. Humans are meant to get exercise, and not getting exercise is probably a huge part of why many people get high blood pressure to begin with.

**TL;DR: Exercise may raise blood pressure short-term but improves control over the long term. Bodies can't regulate blood pressure too good if they sit all day.**


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

[User] ELI5: Why do chords in instruments sound good, but if you play random notes, it doesn't sound that great? What property of sound makes chords sound good?

[Assistant]
Notes in a chord are in a very specific pattern.

Let's take for example major chords. They are composed of the root note, the fifth, and the major third. What does fifth and third mean? For example if C is the root note (this is the case for the C chord), then the fifth would be the (count to 5... C, D, E, F, G) the G note, and the third would be E. (In this case it is the major third, while the minor third would be Eb. But let's not dig too deep)

Back to the pattern: fifths and major thirds have a very specific frequency. If the root note vibrates at X Hz (for example the "middle C" is 261.6Hz), then the fifth vibrates at 1.5X (for example G is 391.995Hz) or in other words their frequencies are at 2:3 ratio. For the major third the frequency is 1.25X and the ratio is 4:5 (E is 329.628Hz).

Other "even" ratios will give you other "nice sounding" notes, e.g. 1:2 will get you the higher octave note, 5:6 will give you the minor third, etc

The more easily your brain can recognize the pattern between notes, the more familiar/pleasant the chord will sound. Uneven relationships between notes result in unpleasant/frightening experiences; this effect is used for example in alarms and horns to signal for danger.