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

[User] What makes it so that Meteorologists can't accurately predict the weather a week into the future, but climatologists can accurately predict 20, 30, even 100 years into the future?

[Assistant]
Question for you:

Roll a pair of dice, over and over. Can you predict what the next few rolls are going to be? Obviously not. Can you predict what the average roll will be over the next 1000 rolls? Quite precisely, yes.

Weather and Climate is similar, albeit a lot more complex. The short term, heavy fluctuations, often on a time scale of hours to days, make up what we call weather. Over longer timescales, these fluctuations average out, resulting in relatively stable values that we call climate. However, unlike a good pair of dice, climate can change over time, usually very gradually, currently a bit faster than we feel comfortable with.


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

[User]
CMV: if they can't afford to pay them that, they don't deserve to be in business anyways" isn't a good argument.

This is an argument that I see a lot around the minimum wage topic but to me it seems like more of an emotional argument that doesn't consider real economic implications.

I personally am the type to assume large minimum wage increases don't actually help people and have potential to do a lot of harm. If your argument is that companies that can afford to pay their employees more should I can at least understand that.

I don't understand the argument that companies deserve to go out of business anyways if that's what a minimum wage increase causes.

I don't understand the idea that going out of business and not paying anything is a better alternative to not paying what is seen as enough.

You could also just as easily say "if your skills aren't capable of creating value over $15 you don't deserve to have a job."

obviously that's a very different argument but it seems like the outcomes from the arguments are identical.

It just seems like it's possible to still at least make a case that min wage increases are better overall, but it makes no sense to say it's totally better even in cases like this.

[Assistant]
I like to use the robot metaphor:

If you have a machine performing a valuable talk for your company, the upkeep of that machine is part of your operating cost. You have to pay to power it, to upgrade it, to fix it when it breaks. And if you cant afford the machine, the manufacturer doesnt have to do business with you. Theyre free to take their service somewhere else where they think the price is fair and where people who can afford to pay for their services live.

For humans, a living wage is the operating cost. If you cant afford to pay your worker enough to live nearby, feed themselves, and get basic health care - all of which are things they need in order to be able to work for you - youre failing to pay for the cost of their service.

The difference is that humans have to eat, like, all the time, so they often dont have the option of taking their business somewhere else if the price isnt fair - even insufficient food and shelter is better then starving on the street. But that means those people are not really able to act as agents in a free market, and its easy to exploit them under the guise of the market setting the price. People cant act like reasonable economic agents when theyre desperate. The whole point of a minimum wage, as explicitly stated by FDR, was to eliminate "starvation wages" and force employers to pay their employees a "prevailing" wage, because the majority of businesses will pay their workers as little as they can legally get away with.

**Alternatively:** Asking people to work for less than a living wage so you can own a business is entitlement at its finest. You are asking human beings to use their lives to subsidize your desire to own a business. A living wage for your employees should be required and expected of all business-owners whether paying your employees a living wage would put you out of business or not. The argument that "practically and economically" businesses will shut down if they have to pay their workers speaks to a broader point that if businesses are using this argument, they are admitting to consciously exploiting human beings to turn a profit...in which case no, they do not deserve to be in business. If a full-time job is worth being done, it is worth being paid enough to live.


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

[User]
If Humans and Neanderthals are separate species how was there interbreeding?

The way my college bio professor explained it is that crossbreeding between species creates infertile offspring if at all. I have heard that scientists believe some of our DNA can be traced back to crossbreeding with them. I asked my professor but he didn't seem to have and answer. He just said sometime there are exceptions.

[Assistant] Species aren't always as cut and dried as that. Some interspecies hybrids are fertile. Homo Sapiens and Homo Neandertalensis both have 23 pairs of chromosomes, and there's a commonality of about 99.7% between the two genomes. The concept of species is a human invention, has nebulous boundaries, and is especially difficult to accurately apply to extinct specimens.


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

[User]
CMV: No one should have guns. No guns would be more peaceful and less chaotic. Humans owning guns is bad.

Guns make things more extreme. So, if you are happy and on a hunting trip, you will derive even more pleasure from having a superior weapon. Guns in the hands of someone who is angry can become violent. Guns in the hands of those in a military mindset will use their weapon more responsibly. Guns in the hands of those who aim to good, allows them to do good. Guns in the hands of those in positions of power and used without reason or justice is bad. Also guns in the hands of those seeking to do evil, it is an extreme benefit because they can quite literally be a loose cannon and just bring destruction to wherever they see fit.

So, when you take all the pros and cons together, you see that the only benefits that can be derived from guns are by gun enthusiasts or people that use them in a utilitarian sense. The cons however are extremely bad and affect more people in a more general way. the cons affect EVERYONE, including those with guns and those without guns.

ALSO, if everyone in that night club had possessed a fire arm, the casualties would have been tenfold. We are talking mass confusion no one knows who the shooter is, and they are all holding guns trying to figure out who the shooter is. so the first person to shoot the shooter would get shot because he is shooting someone. and then the person that shot them and so on. A chain reaction that would have been devastating.

Those of you who say that that the people in the club should have had to go to some type of gun safety course, that doesnt help the situation at all. Let's say all the occupants of this club had guns, and had been trained to use them the way we train the military, would that not be the absolute worst thing for police officers and authority figures? training someone to be as good with a gun as a soldier, but with 0 accountability, we would see just a breakdown of society. Armies of different groups of people gathering in the streets and with military skill, they'd be able to destroy any type of police opposition just based on their numbers and the mob mentality. and then what happens? the republicans start fighting the democrats in the streets? Or race wars? religious wars? I think people that are pro guns actually like gangs, and they like the instability and corruption of other countries because these are the steps to take towards chaos.

Don't make this thread about "how would you collect the guns?" and all those silly arguments. this is hypothetical. No guns = better standard of living.

EDIT: I also think that with a fast universal free healthcare system (like the ones of the future that are heavily automated) we can start to help the people with mental issues so that we can help them live better lives and help people around them have better lives too. I understand the mental health aspect.

EDIT EDIT: I misspoke about the Mongols. My bad. Let's get this back on track. Prove to me that guns are good and make life better.

[Assistant]
If *literally* no one had guns, well... we've seen what that world looks like, and it's actually quite a bit more violent, because at that point, the strong rule and the weak do what they are told. It's called feudalism.

Guns are the great equalizer of democracy. The weak are no longer intrinsically subjugated to the strong.

Governments are not more trustworthy than people. Look at history, they are the most violent and the most repressive organizations ever.

But if you take away their guns, then and only then perhaps it could be safe to take away the guns of the people.


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

[User] [Marvel] Does the Punisher ever punish the wrong people, like someone is framed or the person is actually an undercover cop that did nothing wrong? How would he feel about it?

[Assistant]
Punishers first appearance was trying to kill Spider-Man cause he was framed iirc.

Also it's been so long since I've seen it but in the movie Punisher: Warzone, Frank killed an undercover agent during one of his killing sprees. He's so racked with guilt that he actually goes to the dead agent's house to give money he stole from the mob to his widow and daughter and even offers the chance for his widow to kill him right there.


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

[User] [Everything] How come when giving blood for a ritual/scientific test/etc..., the person always cuts the palm of their hand to get the blood? That seems like the most inconvenient place for a cut.

[Assistant]
It looks cool, and it's important to have style when performing rituals.

Did not look good at all when Chad wanted to make a small cut on his calf instead, lost his balance standing there trying to cut his pale, hairy leg, tripped over his Robe of Dark Offering and fell on several of the Lights of Summoning, brushed out part of the Pentagram of the Abyss, and spilled Dave's tea.

The whole demon summoning ritual was completely destroyed.

Fucking Chad.


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

[User] ELI5: Why do snipers open their mouth when shooting?

[Assistant] They don't. Precision rifle shooters pull the trigger during their natural respiratory pause. Some people breathe through their mouths while shooting, some through their noses, but they don't 'open their mouths' while shooting.


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

[User]
Conservative anti-capitalism?

Most anti-capitalist critique seems to come from the left but are there any right wing philosophers who are critical of capitalism?

[Assistant] Patrick J Deneen's Why Liberalism Failed comes to mind - in the book he critiques liberalism as an inherently flawed ideology partly from a 'conservative' angle regarding its social politics (selling his viewpoint short here but it works) and from an economic angle too, arguing that free-market capitalism erodes the traditional social bonds that conservatives seek to defend.


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

[User] ELI5:Why are uncontacted tribes still living as hunter gatherers? Why did they not move in to the neolithic stage of human social development?

[Assistant]
The documentary "Guns Germs and Steel" tells exactly why this is the case.  Basically, it breaks down to the availability of resources necessary to reduce human labor to the point that farming is possible.

Large domesticated animals and soil good for planting are both required for farming, and those tribes generally have access to neither, just as a mere coincidence of their location.


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

[User]
How can caffeine be calorie free but still give me energy?

A calorie is a unit of energy, and caffeine gives me energy, so how can it be calorie free?

[Assistant]
Caffeine doesn't "give you energy". It is a stimulant that reduces your body's ability to react to a chemical (adenosine) that makes you feed drowsy. You then believe you feel more awake and alert.

There is a major irony here, though: caffeine increases brain metabolism rates, but simultaneously decreases the blood flow. So you may not be making the best decisions, or learning and performing particularly well, though you think you are perfectly functional.


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

[User]
[Marvel] What's the deal with Carbonadium anyway?

AFAIK it was created by the USSR as an answer to Adamantium and it is more flexible but less durable (while still being effectively indestructible for all practical purposes).

For one thing, doesn't that make it superior to Adamantium?  Why doesn't everyone use that?  Yes, there is Carbonadium poisoning but Adamantium poisoning is a thing too (which makes me wonder what the deal was with Bullseye when he got some grafted onto his bones), right?

If the answer is that the techniques to make it were lost (and presumably that means all the Carbonadium swords out there were made in the past by the USSR or their allies), that brings me to another question:

I know that a Carbonadium sword can mess with Wolverine's healing factor (do Omega Red's tentacles?).  Why exactly is that?  Could Wolverine have survived having Carbonadium bound to his bones instead of Adamantium?  What about Feral Wolverine?

[Assistant]
Problem 1: It's not so much normally poisonous as it's *radioactively poisonous*. Anyone using it would soon succumb to radiation poisoning without some other factor to protect them.

Problem 2: Only one device is known to consistently make it, and most of the world thinks that device, the Carbonadium Synthesizer, was destroyed.

Now about Wolverine: Omega Red's tentacles do disrupt healing factors, but at that point the life draining properties become a much more immediate problem for anyone caught in them.

The why is pretty simple- they're highly radioactive and are constantly damaging and destroying the DNA of cells while they are in contact with a victim. Healing factors require the cells to reprogram themselves on the fly to become what the body needs to heal, and it's difficult or impossible to do so while the instructions for that reprogramming are being blasted apart by subatomic particles.

Since Carbonadium damages healing factors, it's unlikely Wolverine (of any variation) could've survived the process that created his skeleton if they attempted to implant it. However, knowing the Weapon X program, there's a few corpses buried someplace on which they tried.


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

[User]
Why did RSS fade away over the past decade?

I still rely on it heavily on my sites that have user generated content for sharing. Its such a great way to digest information. Is it just because spammers were exploiting it?

[Assistant]
it has been replaced with 'follow' on fb, ig, twitter, linkedin.  it used to be that people who created content had their own blogs on blogspot, wordpress and so on.  i used to subscribe to their rss feeds only as a way to get notified when they published something new.  i was subscribed to rss feeds 100s of sites, and all i had to do was to check the rss feed to find out who had posted something new.

now there are platforms for people who want to create and share content like facebook, instagram, youtube, twitter, linkedin to name a few.  these are closed user groups but they have 100s of millions of users.  if you are interested in content created by someone, you do a platform specific subscribe action, termed 'follow'.

most publishers using 'traditional' platforms (blogs, own websites, etc), still create accounts on these social media platforms and post short summaries with links to full content on their sites. now if you want to be notified of new content on websites, you create an account on one of the platforms where they have presence and follow them there.


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

[User] ELI5: Could someone with a decent amount of wealth actually go to an extremely small or third world country and begin turning things around? As in, providing funds and say, education?

[Assistant]
more fundamentally you need to provide an economy, not just demand or supply (Like the US did in the mideast and afghanistan versus what we did with germany and japan, very different)

China is investing heavily in the 3rd world, they will get massive returns so this is already happening. What is important to control is corruption, that is the main limiting factor.


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

[User]
[Thor Ragnorak] Early in the move Hela caught Thors hammer, held it up for a moment, and then crushed it. Does this mean she is worthy?

I remember seeing her depicted in the ancient palace art holding the hammer. She certainly doesnt act very worthy, so what exactly does worthy mean?

[Assistant]
Back when she was Odins favorite, roaming the Nine Worlds and conquering was what they did. She was in line with Odins values at the time so she could have been worthy.

In the movie she simply overpowered the hammershe didnt pass its test. And its not clear that she could have lifted it off the ground by the handle or otherwise wielded it as a weapon.


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

[User] ELI5: How do space vessels travel to their destination if the destination is in orbit? Do they travel in a line and meet the planet/moon after calculating the orbit or do they constantly change direction so that they're always going towards it?

[Assistant]
Neither. They are shot in an orbit slightly lower than the vessel they want to dock with and lagging slightly behind the target vessel. Since a lower orbit means a faster orbital speed, they will eventually catch up with the target vessel. Then, they correct their orbital parameters to mach their own orbit with the target vessel's.

Only when they are sufficiently close to their target do they begin to directly accelerate towards it.


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

[User]
ELI5: Why does closing a door lessen the amount of sound that enters a room even though sound travels best through solids?

My understanding is that sound travels best through solids, then liquids, and worst through the air. If thats the case, then why do walls and other barriers inhibit sound travel?

[Assistant]
Because sound will be lost when it goes from one medium to another(for example: from air to water).
  When you close a door, the sound has to make this ' medium shift ' twice: from the air to the door (solid), and from the door to the air.


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

[User]
Being passively unethical is just as heinous as being actively unethical, and should deserve the same attention and repercussions. CMV

I'd like to use an analogy. Imagine you're in a war zone or a famine affected area or whatever. There are refugees that would otherwise die of exposure and starvation if not given food and shelter. You are out of space and out of surplus food, but your neighbor has a barn with plenty of food that he could do without. Your neighbor refuses to let in the refugees claiming that refugees mooching off of him would make him that much less happy, and that he is in his right to not let them in.

Ideally the rest of the village will tell your neighbor to STFU.

I see the passive refusal to help to be completely equivalent to the active drive to murder, as the result is completely the same. The death of innocent human beings.

In this scenario the rest of society is just as entitled to force your neighbor to give up some of his food as they are in doing what it takes to prevent murder. Since the consequences are the same for each, they should treat them as equivalent goals. CMV

**Edit:** Well I'm receiving a lot of replies, some of which are trying to communicate the same message. Yes, it's true that I do not spend all of my free money and time fighting against poverty, that would be unrealistic. However, I have no problem if I were made to sacrifice at least some of my money to do so. It basically goes back to the idea that I wouldn't personally want my taxes to increase, but would still vote for it to happen. In my example, murder and not helping are not morally equivalent on the part of the neighbor. It could still very well be if the village as a whole treated it the same.

One way that it is not equivalent for the neighbor is that attempted murder is still something that should be punished, but attempting to not help is not the same. If he were to be forced to help, there is no need for punishment as the point in helping is to save the refugees, not justice.

Basically, is there reason for the village/society/the government to **not** prioritize preventing murder equally with preventing starvation?

[Assistant] It's almost a statistical certainty that wherever you live, there is at least one person living on the streets.  If he/she dies of starvation/sickness tonight, do you believe that you yourself should be prosecuted for homicide?  You possess the resources to go out and actively prevent that situation, the same as in your analogy.


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

[User] ELI5: What are the benefits that zero-G environments provide to science or manufacturing?

[Assistant]
At the moment its mainly for science. Not much commercial activity in space yet, outside of communication and observation satellites.

The main things that benefit from zero G are things to do with crystal formation, like alloys. Say you have a big pot of molten metal alloy. As it solidifies, some alloys form tiny crystals called dendrites. The way these dendrites overlap and intertwine determines the properties of the resulting alloy. In gravity dendrites are subjected to all kinds of convection currents, density fluctuations etc. As such, they grow in very irregular shapes and break before they grow too large. Therefore it is very hard to make an alloy that lives up to its theoretical properties. In space all these flows and currents are drastically reduced, or eliminated entirely. As such you get a much better alloy.

Same thing for many other things relating to crystal formation. Zero G allows for bigger, purer crystals.

If we look a few decades into the future, there are many things that could benefit from a space environment (provided launch costs go down, or we use materials readily available in space). Zero-G means you don't need to worry about support. This allows for much more versatile manufacturing methods. For example, right now silicium wafers used for semiconductor manufacturing are 300mm in diameter. Any bigger than that and the wafer flexes too much. In space the wafer won't flex due to gravity, as such you could conceivably have wafers tens of meters in diameter. Space is also a fantastic vacuum, which would really benefit semiconductor manufacture.

Another cool thing about space is that liquid droplets will quickly form perfect spheres thanks to surface tension. This is pretty useful for several industrial processes.

Zero G also allows you to mix normally unmixable gasses/liquids. Oil and water don't mix on earth, because the oil floats on top of water. In space they'll form a great emulsion for long periods of time. This allows for chemistry that's difficult or impossible on earth.

Space is also a great place for dangerous processes. If some industrial accident leaks thousands of tonnes of neurotoxics into the environment its a terrible disaster on earth. In space nobody would give a shit, outside of lost profit.

All in all, space manufacture would be pretty useful. But only if launch costs come waaaaay down, or we start exploiting asteroids and set up a nearly independent industry in space.


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

[User]
eli5, what happens to the dead bodies in a battlefield

Humans war against each other all the time, and throughout history hundreds of millions of people have died on the battlefield.

This begs the question, what happens to the bodies?

Like on the beaches of Normandy, thousands of people died. But the beaches, to my knowledge, aren't filled with dead bones and stuff.

So where did they go? Is there a secret service that collects bodies?

[Assistant]
There are special units in militaries whose job it is to collect/clear bodies.

So best case scenario, that unit comes through and properly handled your body.

Middling case scenario is that unit doesnt find you, and whatever locals attempt to give you a proper burial.

Lower case scenario is youre just tossed in a hole and covered up like a mass grave.

Worst case scenario is no one ever finds you and your body is left to rot, decay, and he picked apart by scavengers.


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

[User]
Why does the flu shot cause soreness at the injection site?

I got my flu shot the day before yesterday and my arm is still rather sore. I haven't gotten a non-vaccine shot in a very long time. Do all shots do this?

[Assistant] The inflammation and pain is part of your immune response. Your innate immune system cells detect the vaccine or adjuvants (additives to the vaccine to increase effectiveness) as foreign and dangerous and then release cytokines to recruit an immune response. This will eventually lead to an adaptive immune response that creates immune memory cells and antibodies, but it can also do things like increase vasodilation in the area (to increase blood flow) which also increases the pressure on pain receptors.


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

[User]
ELI5: That weird "out of body" feeling

What exactly is that weird kind of feeling you sometimes have when you're standing or walking? It feels like being extremely lightweight or flying.

[Assistant] You might be referring to something called disassociation. It's quite common and can range anywhere from day dreaming to total amnesia. On the more severe side, it's usually caused by some sort of stress or trauma and is a coping mechanism by the brain.


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

[User] Does state of matter have an effect on the absorbtion spectrum of a material?

[Assistant]
Yes. Absorption spectra change with phase.  The spectra of a material depends on all the ways the system can be excited.  In a solid, for example, you can have excitations of the atomic displacements in the regular crystal lattice, what are called phonons.  You can also have excitations of magnetism (magnons), spin (spinons), electrons (plasmons) etc.  Many of these excitations either don't exist or have a different character in difference phases.  Thus, you can't excite a transverse phonon in a gas, for example.  This means the absorption resonances or bands associated with them disappear.

Spectra reflects all of this and thus changes with state.


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

[User]
How does Marx counter the argument that in communism people are  demotivated to work because it isn't directly making them money?

This is something i wondered for quite a long time. I myself can think of some ways, but I wonder what Marx thought about it.

[Assistant] Well for Marx technology developed under capitalism solved the problem scarcity in materials for reproduction.  In a communist society human labor, or rather, human praxis, is liberated from the commodity form.  Under capitalism your labor is a commodity that is traded and exploited on the market.  So it is understandable from a capitalist paradigm that is a problem; why would you work more for less return when other people can work less for more return.  In communism that should be an absurdity because labor is not a commodity for exchange.  Instead you act to exercise your humanity as a social being and take joy in sharing that with others.


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

[User]
[Star Wars/Clone Wars] During Order 66, did Anakin ever connect the dots between what was happening and the conspiracy Fives warned him about?

His ordeal tracking down Fives and hearing his rant about the conspiracy to hack the clones' brains to hurt Jedi should have stuck out to him when he witnessed Palpatine give the order. Did Anakin ever realize that Fives had been right all along?

[Assistant] It's likely he did, but it wouldn't have been more than a passing thought. At that point, he already knew Palpatine was a Sith Lord and had been up to no good. It wouldn't have come as a shock, much less have made any difference. More like a "huh, now that makes sense." The Dark Side already had a grip on his mind: he was already Darth Vader.


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

[User]
CMV: Tannerite should be illegal

Tannerite is a binary explosive that explodes when shot with a fast moving bullet.

I am a huge firearm enthusiast and I shoot this stuff all the time but seriously question why it's legal.

You can go to Gander Mountain and buy 50 lbs of this stuff straight off the shelf. If you look on youtube you see this stuff demolishing barns, blowing up hogs into smitherines, blowing up vehicles, etc.

I believe it(or its compounds) should be illegal because it's easy to ignite and buy in large quantites, and has the potential to cause serious damage if used correctly. Seems like a matter of time before someone puts these on top of a house or something and shoots it from a few hundred meters away.

[Assistant]
>I believe it(or its compounds) should be illegal because it's easy to ignite and buy in large quantites, and has the potential to cause serious damage if used correctly. Seems like a matter of time before someone puts these on top of a house or something and shoots it from a few hundred meters away.>

It is not easy to ignite, you have to shoot it. With your example for setting it up on top of a house, you would have an easier time just lighting the house on fire.


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

[User] Potentially a stupid question but does inbreeding affect wild animals as negatively as it does humans?

[Assistant]
Not a stupid question. Yes, it does. The same genetic process is at work. Reason is that inbreeding by definition means crossing with a close relative, which is more likely than not to share an overlapping set of "bad mutations". The effects of these mutations are usually masked by the wild-type, or dominant allele (most mutations are recessive).
Inbreeding tends to bring both mutated copies into offspring, where they are expressed. So in any population that gets small enough, inbreeding will inevitably uncover these bad mutations over generations.


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

[User]
[Star Wars] I am a Jedi Knight dueling General Grievous. What stops me from just Force Pulling the lightsabers from his hands?

I would assume a Force user could use the Force to counter me from doing this, but the General has no Force capabilities.

[Assistant] General Grievous' claws lock in place, as has already been mentioned, but a bigger part of it is his reputation and presence. Many Jedi at the beginning of the Clone Wars were easy pickings since they hadn't been trained for war in generations. Faced with a monster like Grievous their willpower and concentration would have been shaken, and with it their ability to command the force. Notice that Grievous still loses to Jedi Masters like Mace Windu and Obi-Wan Kenobi, and pretty decisively.


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

[User]
ELI5: How did eggs get associated with Easter?

It's not like a (Easter) bunny can lay eggs. Also I don't recall any egg/chicken references in the related Bible stories (except maybe the rooster). So how did the celebration of Easter with eggs came about internationally?

[Assistant]
Easter coincides with the Jewish holiday of passover because Jesus's last supper was a passover meal.

Passover is the celebration of the Jews escape from Egypt, but it is also their spring festival.

Spring Festivals are common place through the world, and in Europe existing pagan celebrations were happening during the time of Easter.

Like so many other Christian Holidays, the Church co-opted various pagan traditions into the Easter Holiday. Basically saying "You can keep this up, so long as you put Jesus in their somewhere"

So various things like the Eggs, Rabbits, etc are metaphors for spring and fertility that are leftovers from Pagan fertility and spring festivals that were integrated with Easter. Their original meanings functionally lost to history.

This is the same reason that Christmas trees and various other things associated with the Pagan Yule celebration became part of Christmas. The honest truth is we don't know when Jesus was born, European Christians chose Christmas time as the celebration of Christ's birth because it coincided with Yule and they wanted to replace it with something far more Christian. (Yule was a pretty crazy drunken party and no really compatible with Christian values)


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

[User]
[Warhammer 40k] How do Chaos Space Marines keep their numbers up?

We know Adeptus Astartes recruit regular humans and enhance them. This allows them to replace combat casualties and other fallen Space Marines. However, How do the Chaos Space Marines replace casualties? I know that some Adeptus Astartes ~~see the true ways~~ fall to Chaos from time to time, and even sometimes entire chapters. However, I guess the rate at which new Marines fall to Chaos is much slower than the rate at which Chaos Space Marines fall in battle.

What do CSM do? Do they revive fallen Marine through some demonic power? Do they have some process to enhance regular humans who worship Chaos to the level of a Space Marine, so they can kind of recruit at least?

[Assistant]
There are a few methods:

* stealing geneseed from loyalists
* daemoncubla (I probably spelled that wrong)
* 'undeath' through warp powers

Overall, this is the CSM's biggest logistical problem and one they constantly fight over.


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

[User]
How do you tell your Prof that a part of her class is a total mess?

Online class, mid-semester, prof wants feedback.
A section of her class is an online group project and it's a total disaster.
She doesn't oversee any of the work.
1/4 of the group has literally done nothing but turn in the work everyone else did, 1/2 just says "yeah" and "I agree", the final 1/4 works but can't agree on anything and most wait until the very last minute to do anything, leaving everyone scrambling on Sunday night to try to figure out work that was assigned weeks prior. We've had 3 due dates so far and despite the weeks worth of time we have to do it 1-3 people participate prior to the day it is due and prof hasn't stepped in at all.
Some members of our group don't understand concepts they should have known 3 pre-req. classes prior and it has now fallen on the few working members of the group to try and teach them remedial information.
The project is set up where the first 1/2 is group work and the second 1/2 is individual work. Together is counts for 1/3 of our total grade. At this point, I'm fairly sure my group's lazy work is setting me up to lose lots of points on my individual work because they've failed to complete the work the right way.
I cannot figure out why on earth the prof is letting this go on without saying a single word or helping at all!
I've stressed and cried about this stupid assignment too much.
There are 1000 reasons I need an A in the class, but mostly, I shouldn't have to take a lower grade based on the work of others.
Without any sort of communication or clarification on this assignment (yes I've reached out to her multipul times) I have no idea how my grade will work out.

How do I tell my professor "anonymously" that this project has been awful?
She previously asked us to explain the project back to her so she would know if she needed to change the wording of the original assignment. That makes me think this is a new thing she is trying.

I don't want to come off like I'm being rude or telling her she isn't doing a good enough job, but I don't really know a delicate way to say all this in a way that won't risk offending her.

[Assistant]
Try to explain to her, in the most objective and non-accusing way possible, how you have experienced the project thus far. This way, she can get a good idea of what is happening among the students. Leave out words such as 'awful'.

Furthermore, she has the right to try out a new type of project/assignment and will most likely take constructive feedback into account. You can tell her that you are worried about your grade, as long as you do not attack her.

It can be very difficult to predict how students act during group work and it is very possible she has no idea what is going on if students do not inform her.


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

[User] ELI5: Why do some animals (like spiders or lizards) spend so much time just doing nothing? What is happening and why?

[Assistant]
Most organisms are in a constant struggle for energy. Obtaining energy is dangerous, you have to leave your save burrow or go risk injury in a hunt.

That's why many organisms develop strategies for minimising the risks they need to take. And one of the most popular strategies is simply having simple, low demand physiologies, slow metabolisms and generally low energy needs.

Warm blooded animals are fairly unique. We're like a car with the engine constantly running. That means we're ready to go from zero to a 100 right away but we're also guzzling gas constantly, even if we're standing still. That's why warm blooded animals need toc constantly eat. Some of the smaller more high energy creatures like humming birds can starve to death in a matter of hours.

By comparison, cold blooded animals waste zero energy on body heat. The downside is that they need to warm their bodies up with external heat like sunlight in order to get their digestive enzymes working or to get their muscles ready for fast action.

But on the upside, they need so little energy that they have to take far fewer risks than warm blooded animals. Some cold blooded animals can go up to a year or even longer without food.


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

[User]
ELI5: In Trading Places (1983, Akroyd/Murphy) how does the scheme at the end of the movie work? Why would buying a lot of OJ at a high price ruin the Duke Brothers?

I have a vague understanding, but I'm hoping someone can explain it better to me. And maybe throw in some knowledge about the stock market in general while you're at it? Thank you!

Edit: Hey everyone, thanks for all the great answers! I think I actually really understand futures commodities now. Who ever said Reddit was a waste of time, eh? So yes, this question has been answered, and yes, I've seen/heard that great NPR clip about this topic. Thanks again to everyone!

[Assistant]
The final scene involves future contracts.  This simply means entering into a contract to buy something (oil, wheat, even frozen concentrated orange juice(FCOJ)) at a specified time for the current price.  The person selling the future does not have to own the FCOJ at the time of sale he simply has to provide them at the agreed upon date. Futures help companies mitigate risk against the unpredictable price of FCOJ. If the price of FCOJ goes up the buyer wins the seller loses and visa versa.

This price is often affected by fresh oranges. If there is a good harvest FCOJ price goes down and so on. The Dukes believed there  was going to be a bad harvest.  Their plan was to buy as much FCOJ as they could and basically corner the market then sell it at a much higher price due to a lack of oranges.

So here is what happened.  At first Winthrop and Valentine begin selling futures contracts at inflated prices caused by the Dukes (on the info from the fake report of a bad orange harvest) at approximately $1.45 per unit. When the report comes out that the orange harvest is expected to be good caused a massive selloff and the futures price plummeted to about  $.22 cents.  This is when Winthrop and Valentine begin buying futures instead of selling.  So now they can fill the futures orders of $1.45 with oranges costing $.22 earning something like a 545% profit.


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

[User] What is the correlation between brain size and intelligence? Is it possible for a large-brained animal to be unintelligent or a small-brained animal to be highly intelligent?

[Assistant]
Sure. Rats have tiny brains, but they're quite intelligent. The ratio of brain size to body size matters a bit more than just overall brain size, but there's still not much of a proven correlation. There are just too many factors.

It's probably down to evolutionary pressures in the end. Rats benefit from being very intelligent, but lions can survive just fine without being very clever.


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

[User] [Warhammer 40K] Can Exterminatus happen on ships? What would happen if it were to occur?

[Assistant]
There are multiple forms of Exterminatus.  Virus bombing, which is what it sounds like but with a nice firestorm afterwards (metabolizes the dead into explosive gas).  A barrage of Cyclonic Torpedoes, which just nuke the planet and cause seismic instability which makes it uninhabitable (or possibly cause it to break apart). AKA "The Classic".  Rarer "Two Stage" Cyclonic torpedoes with their crust-penetrating ability are the only thing with a "Death Star" result of turning the planet into bite-sized chunks.  And then there's lengthy space bombardment by a fleet of naval ships, which has much the same result as Cyclonic Torpedoes just in a less cinematic manner.

Viral weapons are rarely used by the Imperium, feeding Nurgle and all. But there are some plague marine variants known for boarding enemy ships with the intention of spreading similar pathogens.  Results vary, larger, higher tech ships have some inbuilt NBC countermeasures obviously.

Cyclonic torpedoes are too slow, inaccurate and expensive for use against in regular ship combat.  Doesn't mean they don't see use however, especially against bigass scary stuff like the World Engine or the Planet Killer.  But usually only as a killing blow against an unshielded, crippled target.

Obviously, ships shoot each other all the time.  But ships have shields and a possibility of being missed, wheras a planet either has the former and doesn't get put down so easily, or gets slowly pounded into oblivion.


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

[User]
How do we measure the frequency of light?

Especially since the resolution might be to several decimal places and that unpolarised light might have the frequency change moment to moment.

With regards to measuring the frequency of distant galaxies - to measure Redshift - how do we measure the frequency of one galaxy and not all the stuff in between and near it. For example, if there were a trillion small dust clouds in the trillions and trillions of meters (in the straight line) between us and the galaxy, the reflection, absorption and reemission of light by the dust, asteroids etc could affect the frequency.

And galaxies extremely far away will blend into one since a second of arc from our measuring equipment will include quite a lot of celestial bodies (1/1296000 of all of them)

And large distances in space, as I understand it, are curved due to the gravitational effects of bodies we have no idea about it (as there are an infinite number of objects with mass in very deep space)

Lots of questions about this.

[Assistant]
Light you see from all natural sources is rarely of one frequency. Its a mix. Only lasers contain one frequency of light.

And we estimate frequency using `frequency = speed / wavelength`. We know speed of light and it is constant. We estimate wavelength using various methods. One is using spectrometer which changes the angle of light related to the wavelength of the light. Similar to a prism. Based on this we can estimate various frequencies coming from that light source.

There are other ways to measure wavelength too. Using interferometer which creates a fringe pattern and since light behaves like a wave it reacts to small slits. Like you say these instruments are very precise because measurements need that precision.


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

[User] [Alien franchise] Although there may be breathable atmosphere, why aren't the scientist crew of the Prometheus concerned about the various alien pathogens/diseases that could infect them on an exoplanet? Why not keep your helmet on just to play it safe?

[Assistant]
There aren't much to worry about alien pathogens infecting you, really.

Think back on Earth. There was widespread panic when a strain that could transmit from pigs to humans back in the day. And that is two practically identical species who frequent each other regularily!

The chances of alien pathogens infecting you are nonexistent.


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

[User]
[DC COMICS] Does Batman knows how Jack Napier became the Joker? If so, what are his thoughts abut it?

Edit: about it*

[Assistant]
Jack Napier is only the Joker in the Tim Burton movie. Fun fact: the name itself isnt a hidden message or reference to the Joker. Its just an homage to Alan Napier, who played Alfred in the 1960s Batman show.

In the comics, no one knows Jokers real name. Hes used false identities like Joseph Kerr, Jack White, and Eric Border before, but no one knows who he really is. Actual telepaths have read his mind and not found that information. Even the *Joker* doesnt remember who he is anymore.

Also, there may or may not actually be three Jokers, one of whom is a centuries-old immortal demon. That idea was introduced in the New 52, but the writers just kind of forgot about it.


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

[User] Eli5: How are submarine deck guns able to still be fired after being submerged in salt water?

[Assistant] They're heavily protected by anti-corrosive paint on the outside, slathered in waterproof grease, and they only submerged with the breech closed and the muzzle plugged. That way, saltwater never got into the inner workings of the gun.


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

[User]
Does falling asleep with your T.V. on negatively affect your circadian rhythm?

I've done it for quite a few years now, and don't have the best sleeping habits (being a Redditor doesn't help either). Just curious if it would help to stop the habit.

[Assistant]
Are you asking if the light coming from the tv set is messing with your circadian rhythm?

There are some studies in teens showing that the more electronic equipments kids have in their room, the less they sleep. This considers tvset, computers, videogames etc. The rationale is that having a distraction in your bedroom will delay your sleep time.

If you have problems sleeping, then it's probably for a similar reason rather than for the light emitting from your tv screen. It is possible to affect circadian output (as measured with melatonin in the urine) by modifying light exposure but it's controversial how important that is. For instance you can adjust circadian rhythm in shift workers by reducing their "bedtime" light exposure but this will not improve their overall feeling.


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

[User]
[Age of Ultron] If Ultron could've survived and rebuilt himself if only one of the robots survived, why didn't he just send out heaps of robots in different directions instead of keeping them all in one place?

He only needs one so if he sent 10 or 20 robots off in different directions to just hide and wait, it'd be much harder to completely destroy him or even find him right?

[Assistant]
He had backups, just not in the form of robots.

Ultron has stored copies of his consciousness all over the internet. This what Vision was erasing when he made contact with him during the battle.

So he did make backups for himself, just purely electronic ones and he kept each robot of the Iron Legion by his side because he would need every spare body he got to occupy the Avengers while Sokovia reaches the needed altitude.


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

[User]
ELI5 why submarines use nuclear power, but this isnt more commonly used on land?

I understand the fear of meltdown but how is it it isn't an easy fix,and is that the main reason why?

[Assistant] Nuclear power is especially beneficial for submarines because it means they do not have to refuel or surface for air (for a very long time). This makes it much easier to operate in secret. No alternative to nuclear power offers this benefit. On land, that concern does not exist.


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

[User]
[John Carter of Mars] Questions in general.

1. The omnipotent people, what's their deal, do they not have anything better to do than help civilizations destroy themselves. I mean they even go on to explicitly say, they don't bring about the end, they just help it along, which means the end is going to happen, so why help? Why not just go be immortal elsewhere.

2. After John Drinks the liquid that lets him speak English, he goes onto to talk with a girl about the planets, and she calls them all things he couldn't understand. Why didn't it translate the planets names into English?

3. Kind of nit picky, but how come John, or the martians didn't get sick when interacting? Hell, I've got to take shots just to leave my country, yet he can leave the planet and his immune system holds up just fine?

4. John got sent back to Earth and he was visibly older but not dead. Apparently the thing that sent him to mars simply copied him but sent his consciousness to Mars. I ask why his body on Earth was older, but not dead since he didn't eat or do things people need to do.

5. The aliens that wanted to kill John on Mars, sent him to back to Earth and didn't kill him there, they just sent someone to watch him. Why not just kill him?

6. The aliens orchestrating the destruction of mars, said they don't bring about destruction they just help it along. They also said for all intents and purposes they don't even exist. Yet in the end, one of the aliens is seen by several of the martians, wreaking havoc at the wedding, killing people, and firing off crazy new weapons, why would he do all of this if he's supposed to be a shadow?

7. On Earth John spends a lot of time finding a way to get back to Mars after the aliens sent him back. So much time it seemed to be years, yet when he does get back to Mars it's like no time had passed. What gives?

8. Final question: Was this something of a time travel flick? The mars in our space now, couldn't be so busy, as to be having a war going on, could it?

[Assistant]
#3

You've got to take shots because you are visiting places with other humans (any disease they can contract, you can contract).

Diseases typically don't jump around species easily even when they share a lot of common DNA and other commonalities.

The Martian flu won't have any clue how to infect you.


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

[User] [Marvel] I just gunned down the Board of Directors of Nestle. Would the Punisher come after me? What about Captain America?

[Assistant] The Punisher will, and has done so in the past. In the early 00's there was a few vigilantes that were inspired by the Punisher. One of them targeted corrupt companies board of directors, killing the board by shooting up one of their meetings and killed the CEO with stinger missile while riding in his private helicopter. This killer was later hunted down while meeting with other vigilantes, the Punisher killed all the vigilantes. But before he explained why he was killing them, his reasoning was that during the board room shoot up the vigilante had killed an innocent cleaning woman in another room with a stray bullet. Frank Castle doesn't like other vigilantes mostly because they are sloppy, he tolerates Daredevil, Spiderman and other heros mostly because how hard they try to bring in people in alive. Frank doesn't like it when innocent people die and most vigilantes that kill tend to have unacceptable collateral damage.


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

[User] ELI5: Why does water expand in volume when freezed? Shouldn't it be more compact now since it is a solid?

[Assistant]
In most cases, when something freezes,the molecules pack more tightly than they are on average when flowing around each other as a liquid.

In the case of water, however, the molecules form layer upon layer of a hexagonal crystal structure that encloses about 10% more volume that the molecules take up in liquid form. This means that ice is *less* dense than liquid water.


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

[User]
CMV: When talking about victims of the Holocaust, it is ignorant and racist to condemn it because of the deaths of 6 million Jews.

When the Holocaust comes up in conversation, people immediately throw around the number "6 million Jews" when talking about the victims.  Others will echo the number and talk about the horrors of the death camps and what it must have been like to be a Jewish person there, and also, isn't it horrible that 6 million Jews died in the camps?

Apparently the 5 million non-Jews who died are not worth mentioning.  Apparently they don't matter.

Fact is, approximately 11-12 million *people* died in Hitler's death camps.  If you're talking about the horrors of the Holocaust and you only mention the 6 million Jewish victims, you are spitting on the graves of the other 5-6 million people who were every bit as human but not Jewish.

Imagine a plane goes down and the newscaster says "Horror in the skies!  Plane crashes and 87 white passengers die!"   Wouldn't you say "WTF?  Why are they only talking about the white passengers? Don't the other passengers matter?  Aren't they worth mentioning?"

[Assistant]
It's wrong to focus *just* on the 6 million Jews.  What matters more is that 6 million Jews represented ~40% of the world population of Jews.

That's why it's worth mentioning.

>Imagine a plane goes down and the newscaster says "Horror in the skies! Plane crashes and 87 white passengers die!"

You picked a bad example.

Imagine that a plane crashed and among the victims was an entirety of a soccer team.  Do you think the fact that a soccer team was wiped out would be worth a separate mention?


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

[User]
ELI5: How come movies that are universally panned can have trailers where the critics say that it is "epic" or "a must see?" Isn't that false advertising?

I heard one of the Transformers 5 trailers do this.

[Assistant]
they're finding the one good review and pulling quotes from that. Whenever you see a quote from a reviewer in a TV commercial, you should always look closely to see where the quote comes from. If it's not from a well-regarded publication, it's pretty safe to assume the movie's gonna be bad.

Also a reviewer could say Transformers has "epic visuals" but then shit on the rest of the movie, but the commercial will just pull the word "epic" and go with that.


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

[User]
[Star Wars] Hold up, so I just heard from the Supreme Chancellor that the jedi, a peaceful group of religious "monks" just attacked him with not a single witness, and the best way to go from here is to turn our democracy into a dictatorship? And everyone is for this?

Rip my inbox.

[Assistant]
Did you see that dude's face?  Nobody would do something like that to *themselves.*  He looks scary now; it was probably some of that weird Jedi magic that they do.

And for all that "peace" those Jedi preach, they sure have been doing a lot of warring lately.  And it seems like they can just jump into battle without armor, kill a thousand enemies, jump back out and head home.  It was always just a matter of time until they tried to seize power, I've been telling you guys for years.  The Chancellor knows what's up.


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

[User]
[DC] Is it common knowledge to the public that nightwing was Robin?

Does the public know nightwing is Robin? Like, nightwing and Batman work a lot, and are similar, but have people made the connection between the two?

[Assistant]
It would be theorised, Robin led the Titans then left and someone with similar features and skills called Nightwing came along to lead them while a new younger Robin appeared in Gotham

Theres also the point the villains they fight would notice immediately and word would spread through that.


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

[User] [Physics] Why is it that raindrops on a window seem to prefer following the trails of their fallen comrades?

[Assistant] It's to do with the molecules on the droplets' edges wanting to reduce their energies. A molecule in the middle of the droplet gets pulled on by all of the molecules around it with an equal force as they're all the same, whereas on the droplet edge a moleculesis also getting pulled on by the surface molecules, who will exert a force of a different magnitude. This creates an imbalance and causes those molecules to sit in a higher energy state. As such, the droplet will follow the path that surrounds these molecules with water instead of exposing them to the surface, therefore reducing the energy of the molecules at the edge, and as a consequence the energy of the droplet as a whole.


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

[User]
[The Thing] say Childs is a Thing at the end of the movie. What most likely happens after? Assuming he is a Thing, why not torch MacReady?

I know theres the video game, but I dont know if it explains how they escaped, and it shows Childs frozen, but I dont think we learned if Childs was Thing or human.

So what if Childs was a Thing at the end of the movie? Logically, do you think people would go check on the base/come as rescue? While it is an isolated camp, I think if there wasnt a response for a while, people would eventually go look at the camp.

For the second question, remember Childs had a flamethrower at the end. I think it comes down to two answers: either Childs saw the flamethrower Mac had, or Childs wants to assimilate Mac. Which one is more likely? Or is there something else thats likely?

[Assistant]
Childs was almost certainly a Thing (*the drink was the clue*).  He had no reason to escalate the situation, though.

His course is logical.  If he attacks MacReady, he risks permanent death by being burned alive.  If he does nothing, they both freeze and he wins when their bodies are eventually discovered.  And they *will* be discovered.  Their sponsors will definitely mount a rescue/retrieval mission.


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

[User] ELI5: How does Baileys have such a long shelf life when it's mainly made of cream ??

[Assistant]
Alcohol! Among other things, alcohol is an excellent disinfectant so nothing can grow in there to spoil the cream.

If you leave Bailey's alone long enough, it will eventually curdle/clump, which isn't exactly spoiled but is still disgusting.


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

[User]
ELI5:Why is it so hard to NOT read subtitles?

Whenever I go to the cinema to watch a movie I have to focus to not read any of the subtitles since I don't need them.

[Assistant] Visual perception in the outer regions of our visual field reacts mostly to movement and changes rather than clear vision (so you would see a danger in the corner of your eye and be able to react to it). Focusing on the center of the screen pushes the subtitle into the outer region of your field of vision, making it trigger that effect - ie you have an instinctive urge to look down any time it changes. It takes conscious effort to suppress that.


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

[User] When you spin yourself in an office chair and pull your legs in you spin faster. What is this called? Besides fun.

[Assistant]
Conservation of angular momentum.

Angular momentum is a physical quantity that represents how much something is rotating / spinning. It is computed by first selecting a fixed point and then multiplying the distance of an object to that fixed point by the mass of the object and the velocity that it has perpendicular to the line connecting the object and the point.

So angular momentum is proportional to the distance to the point, the mass of the object and the perpendicular velocity. Since angular momentum is conserved, changing one of these variables will cause a corresponding change in the other. Since mass tends to not change, this effect usually happens between the distance and the velocity.

In case of the spinning office chair, when you have your limbs extended, their distance to the point of rotation is larger. When you pull them in, you decrease this distance. Since angular momentum is conserved, this causes the velocity, and therefore the rotation speed, to increase.


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

[User]
Are lasers (when viewed as radio antennas) subject to the antenna reciprocity principle?

Since lasers emit electromagnetic radiation, are they subject to the reciprocity principle? I know that the principle is only for (electromagnetically) linear antennas, but I am not sure if a laser is linear. The second question then pops up, as lasers are based on diodes, are diodes subject to the reciprocity prinicple?

[Assistant]
The laser diode as a whole cannot be thought of as an antenna by itself, It can be thought of as an array of phased antennas made up of the excited atoms.

The individual atom harmonic structure follows reciprocity only up to the point that photon in is the same as photon out in a time reversed format, This is true for any quantum interaction.

But the device as a whole is not conservative in that respect, Firstly modern diode technology is dominated by non-radiative transitions (60% +), Meaning that emission of a photon is not always the case, more often than not it's is released as a surface wave (phonon) when the mean free-time of the electron-hole pair is less than that of the mean time to photon emission. This is somewhat helped in a laser diode as the stimulated emission increases the chance that a radiative transition will happen. (this is why laser diodes can be more efficient than a regular LED)

secondly, the diode cannot be thought of as a coupling the same as an antenna, it is more accurately thought of as the laser pump, same as the xenon flash bulb in a gas laser. It's not a reversible pathway, except to the extent that it starts acting like a photo-electric cell.

But in an idealised structure, where non-radiative recombination is nil and efficiency of 100% transmit and 100% receive conversion, it could be an analogue of reciprocity.


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

[User] [WH40K] are religious deities present in the Warp?

[Assistant] For some races, yes. Or, at least, they were. For humans, it does not seem so. Human religions seem to have been born more out of alien contact or, in the case of the Abrahamic branch, the Emperor's direct involvement.


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

[User]
ELI5: How do long rivers work?

The Mississippi River is 2,320 miles long and only drops 1,475 feet in elevation over that length, an average of 7.6 inches per mile. It seems like the water shouldn't be able to keep flowing with such a minor elevation change.

[Assistant] Why wouldn't it? The water that gets into the river from its surroundings needs to get somewhere (because water tries to spread in all directions) and ultimately, when the river is filled with water, the only possible way for the water to flow is in the direction of the drain no matter how small the elevation drop is.


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

[User] ELI5: Why is the internet's upload speed usually a lot slower than the download speed?

[Assistant]
With adsl type connection. There is a limit in bandwidth so you prioritize download since that is what most user use internet for.

Later on it was used to prevent people from running upload servers since they were a big expense for ISP.

Fiber connections today dont have a bandwidth limitation and people dont run servers at home anymore so most fiber isp run same download / upload.


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

[User]
ELI5:Why do dating/mating standards slip when under the influence of alcohol?

We've all been drunk and taken home someone you regret in the morning. I was curious to know if there is any scientific reason for lowering our standards. Also if this is the same reason for so called 'Dutch courage'.

[Assistant]
Our inhibitions are lowered. Internally we would have always taken home that regret, we just had a bunch of reasons not to. When we're drunk, we stop caring.

By the way, remember that if a SO cheats while drunk. It's not that the alcohol made them cheat, they wanted to cheat, they probably still do, they just had a bunch of reasons not to. Alcohol made them stop caring.


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

[User] ELI5: Why have we not landed on the moon recently when advances in technology should make it cheaper, safer, and easier?

[Assistant] It's still really, really, expensive. And the moon itself isn't all that interesting for someone to land on, we can do some great research without sending folks there. Lots of other stuff in the galaxy are more interesting right now, like Mars, so we are focusing there.


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

[User]
[Interstellar] Why did no one seem to care when Cooper made it back?

Once he gets back to when Murph is an old lady, you'd thing it would be a bigger deal than astronaut had been gone for that long (relatively) and had experienced time dilation, been responsible for sending a message to his daughter, etc. Not even an acknowledgment from Murph's kids or grandchildren?

[Assistant]
Unlike Murph, Cooper didn't have fanfare or wide-spread knowledge around his mission.  Murph was in charge during the exodus from Earth, instrumental to the cracking of the gravity equation, and likely had a major part in the post-Earth government. Meanwhile, Cooper was a line in the students' textbooks (if even that) about a last-ditch effort to move the population off the planet.

Cooper also doesn't seem like the kind of person to go seeking out that kind of attention.  We see him relaxing in an out-of-the-way part of the habitat, then sneaking off on his own to go back into the wormhole.

No one remembers Ghandi's father or mother in the wider world.


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

[User] ELI5: How do controllable prosthetics work? How does the brain control something that's artificially attached?

[Assistant]
Simplest prosthetic is where you just lost your hand. Since basicly all muscles controlling the hand are in your arm you can just put sensors near those that detect activity and rig it up to the right limb.

It gets harder the more is lost, but the principle is the same. Find an unused nervbundle/muscle group. Put a sensor on it to control the arm. Doesn't even really have to be the same nerves that controlled the original arm because the brain can be retrained.


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

[User]
ELI5: Why is it that we can eat extremely spicy food and enjoy it but afterwards our stomach and toilets are destroyed?

Asking for a friend and totally not because Im dead in the toilet now after eating and enjoying extremely spicy food

ETA: I meant like why does it feel like we are taking a dump from the pits of the hottest hell?

[Assistant] Your butthole actually has similar receptors as your mouth and tongue, as well as the one that detects spicy. The capsaicin that makes things spicy is waxy, so it sticks to things it touches and is hard to get off. It's also not easily digestible, so some of it will pass all the way through and get stuck on your butthole when you poop. Since your butthole has the spicy receptor, it burns!


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

[User]
[Star Wars] Why did Revan and Malak betray the Jedi Order?

I know Revan and Malak are legends and probably were not real but I'd like to know what exactly was the Jedi Civil War and why and how Revan and Malak betrayed the Jedi Order.

Bonus points for a little backstory on the Mandalorian Wars and what led up to it, which is the event which led to the Jedi Civil War.

[Assistant]
The Mandalorian Wars were just that, a war against the Mandalorian people. They were a warrior race from beyond the Outer Rim that lived to fight and conquer. When they showed up and started rolling through planets, the Republic just couldn't stand up to them, owing to their complacency from long peace. The people begged the Jedi to intervene, and many of the young Knights wanted to help, but their Masters decided to wait and meditate on the issue before acting.

This is where Revan and Malak come in. Revan was extremely talented and charismatic, with a major following among the younger members of the Order. After some rabble rousing, Revan led a large number of Jedi in deserting the Order and joining up with the Republic forces battling the Mandalorians, and they immediately gave command to Revan. He quickly displayed his tactical genius in stopping the Mandalorian advance cold, and then pushing them back, winning battle after battle. Revan was often coldly strategic and wouldn't hesitate to order men to their deaths, but his people followed him fanatically. Eventually the Mandalorians were defeated in one major battle at Malachor V with the use of a super weapon and at the cost of many lives. The Mandalorians were completely crushed, with the few survivors scattered throughout the Galaxy, but all of them had a deep respect for Revan and held him solely responsible for defeating them.

The Republic was pleased that the war was over, but instead of returning as heroes, Revan took the ships, men, and Jedi under his command and disappeared for several years. When he returned it was as Darth Revan and with a new fleet of ships, calling themselves the Sith Empire. This had been Revan's true purpose. He left the Order to gain an army and track down an ancient space station from a long dead race. Powered by the Dark Side, this station could crank out unlimited ships and weapons, which Revan used to fuel his campaign to conquer the Galaxy.


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

[User]
ELI5: how did shuttlecocks come to be and why are they only used in badminton?

I can't imagine a context where anyone would think to invent them and why has no other use been found for them?

[Assistant]
So the best explanation I've heard is that the name comes from the motion of the game reminding an onlooker of the shuttle on a loom, and it is feathered like a rooster aka cock.

As for the design, high-drag projectiles (aka balls/corks with feathers on them) trace back to 5th century Vietnam with a game called Jianzi and even earlier then that to an ancient greek game ~0 AD called "Battledore and Shuttlecock".


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

[User]
Travelling away from earth what will happen to incoming transmissions?

If i travel away from earth wit ha spaceship with high speed, what will happen to radio transmissions?
If i can tune in to a radio station, will the sound be slower or something?
I'm sorry for the crappy explanation, i will try an example too:
-I travel away from earth with 0.25 of light speed
-A radio transmission will come after me with light speed
-What will i hear compared to what people on earth hear?

[Assistant] You will receive signals (emitted at the earth) with a slightly longer wavelength than people on earth will perceive, and those signal will arrive with longer gaps between consecutive transmissions, effectively making the signals seems like they are in slow motion. This is one way to conceptualize time dilation between frames moving relative to each other.


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

[User]
What would fire look like under a microscope?

I'm in biology using microscopes, and this thought just hit me, so I googled the question and nothing came up. I was wondering if you guys could help me out.

[Assistant]
It would look like a floating aerosol of soot and dust, each particulate of which would be bright enough to be glowing.

So you know how when you poke a log that's burning and a bunch of glowing embers are kicked up? Keep magnifying and it would look like that.

This is assuming a candle type fire. If you're talking about a gas type fire (like from a kitchen stove or Bunsen burner), it would look the same for all normal microscopes, because it's not glowing soot that you're seeing, but actually the atmospheric gases are so hot that *they're* glowing. So it would look roughly the same.


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

[User]
Why do chameleons walk like that?

You know, all herky-jerky and whatnot? Are they pretending to be leaves blowing in the wind, or, like, trying to throw off the T-Rex's motion sensors?

[Assistant] That's a good question. They walk in such a funny way because they are trying to mimic the motion of a leaf swaying in the breeze. The idea is that if they look like a leaf predators won't be able to see them, but they do it even when there's no wind which makes it a little humourous.


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

[User]
[Batman] What are some of the redeeming, not-so-dark qualities of Gotham City?

Most know Gotham for it's incredibly dismal, bleak over and undertones, however, what are some of the qualities that keep the residents of the city happy and optimistic despite the constant negativity?

[Assistant]
Gorgeous architecture, hot nightlife, great restaurants, surprisingly active and interesting tech and financial sectors, lots of very attractive men and women, less traffic than you'd expect for a city that size.

No one ever has clowns at birthday parties.


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

[User] ELI5: How do all of my necklaces get tangled when they're just sitting in a jewelry box all of the time?

[Assistant]
There was an ignoble prize a few years ago for answering a similar question. It was for proving that string like objects will inevitably tangle.

The short version is this. With some movement of the strings there are very few ways the string can sit that isn't tangled, while there an almost infinite number of ways for the string to sit that is tangled. The difference in the number of ways the string can lie tangled vs untangled is so large that it ends up having a 100% chance of tangling.

For the jewelry box, opening and closing the lid/drawer, or disturbing the box while putting in or taking out jewelry would cause enough movement of other jewelry in the box to cause them to tangle over time.


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

[User]
[LOTR] Why was Sauron harmed by conventional weapons, when other less powerful creatures aren't?

During the fight against the Balrog Gandalf states that swords would be of "no use" against it.

Later Gandalf, (after becoming "the White") claims that the fellowship has no weapons that can harm him including Aragorn who wields Andril.

Why was Ellendil able to harm Sauron with Narsil if less powerful Ainur are unaffected by the same weapon?  (Sauron was wearing the one ring too!)

[Assistant]
It's not that they are immune to conventional weapons, Gothmog the leader of the Balrogs were implied by a pointy helmet after all, its just that they are damn hard to kill due to being alive for 40 000 years and no one in their company was skilled enough to kill a Balrog or gandalf. Simple as that. Wasn't a matter of durability or kryptonite weapons, just skill.

Sauron was a rather pisspoor physical fighter (atleast compared to his power level as the most powerful maiar) and he faced the most skilled and powerful melee fighters of the second age.


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

[User]
A conductive cable over a light-year long is connected to a positive & negative pole, how long until current flows?

Assuming an infinitely large power source for the current. What would the electrical dynamics be if a cable capable of carrying the current from the (-) end to the (+) end starting the second of creating the complete circuit?
Do these electrical dynamics breakdown at some point of scale?
At this scale could we watch the 'flow' of electricity?

[Assistant]
The current would start to flow as soon as the circuit is completed, but it would travel at a finite propagation speed.

Electrodynamics doesn't break down, but basic circuit theory does. Circuit theory is just a simplified way to look at electrical circuits without solving Maxwell's equations every time. You make certain assumptions, for example in small circuits you neglect the propagation time of electrical signals.

In larger circuits, and definitely in this hypothetical situation you've proposed, you need to consider the finite propagation speed of electrical signals. You have to really solve Maxwell's equations to see how this system will behave. What you'll find is that the electrical signal (voltage or current) obeys some kind of wave equation, where the wave speed is related to the capacitance and inductance of the cable. The signal will propagate like a wave down the cable with some speed v, and it will reach the other end after a time delay of L/v, where L is the length of the cable.


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

[User]
Is it really a bad idea to read the Critique of Pure Reason with no background in philosophy?

I mean I majored in computer science, so I do have some training in logic and being able to think of abstract concepts.

I've read the first two sections of Critique of Pure Reason, "I. Of the difference between Pure and Empirical Knowledge" and "II. The Human Intellect, even in an Unphilosophical State, is in Possession of Certain Cognitions  priori and I seem to understand what the text saying so far.

Does this mean I should be able to read the entire thing? If not, then what would I need to do to get good enough to read Kant? Thanks.

[Assistant]
Notwithstanding his reputation for difficulty, Kant is a very clear writer. He's not perfect: like all of us, there are aspects of his own thought that he takes for granted and so fails to explain well, but he's among the best of us at carefully sorting through his thoughts in a step-by-step fashion, explaining each point along the way, defining each term explicitly, and so on.

The main difficulty with Kant is that it takes much greater sustained attention to follow this rigorous procedure than people are used to exerting. People tend to think that functional literacy is more-or-less a binary condition, and they have it. Though, actually, most people's reading leaves them breezing over much of a text they think they're absorbing and taking note of only a fairly small proportion of it. Precisely because of his rigorous manner, the gaps that our poor reading habits introduce make Kant challenging -- this rigor means that these gaps will tend to omit things we need to have grasped before we move on. To use an analogy, reading Kant is more like following a proof in mathematics than like breezing through the Sunday newspaper.

This applies both in the short term: you need to hold a whole sentence of Kant in your memory to make sense of it, you need to hold a whole paragraph of Kant in your memory to make sense of it. And structurally: Kant will give a definition once, and then expect you to immediately understand the relevant term every other time it appears, and there will be sentences with a half dozen technical terms like this, whose meaning will be obscure if you haven't internalized these definitions. And it's true in the long term: you won't really understand the role of what Kant does in, say, the first section of the text, until you've read 300 more pages after it ends.

But the main challenge is the challenge reading Kant places on one's basic cognitive aptitudes, rather than a challenge on one's background knowledge. If one has strong basic cognitive aptitudes, one can tackle Kant without much background knowledge in philosophy. The difficulty is that one tends not to have the relevant cognitive aptitudes without first spending some time in philosophy to build them up.

Certainly some stuff will be missed without background knowledge. You may be able to follow Kant but, without background knowledge, fail to understand much of his significance -- you don't get what he is responding to, what he's trying to do, and so on. But for the most part you can make some reasonable progress just with strong cognitive aptitudes, if somehow you have them.


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

[User] What happens, on a molecular level, that leads to paper becoming soft after applying water to it?

[Assistant]
Paper consists (mostly) of cellulose fibers, i.e. a polymer of glucose molecules. These glucose molecules have free hydroxyl groups, which can form hydrogen bonds to other molecules.

In dry paper, at least many of these hydrogen bonds are to neighbouring cellulose fibers, which stabilises the overall structure.

Water breaks up the hydrogen bonds between the cellulose fibers, so this stabilisation is lost.


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

[User]
ELI5: Why are concert volumes so high?

I've been going to concerts since I was young. I have never understood why the volume has to be so loud that ear plugs are required. It eventually just sounds like distortion. Does the sound engineer actually think it sounds good?

The question was prompted by a recent small outdoor show in my hometown. It was a latin festival attended by maybe 200-300 people. A professional audio company was commissioned for the band to provide background noise while people ate tacos. The volume was so loud that no one could sit or even walk within 100ft of the stage speakers. The sound engineer was wearing ear plugs. This was a small community event for pedestrians passing by. Was it really necessary for it to be so loud? Could the sound engineer just dial that volume knob down a little?

[Assistant]
Concerts are usually too loud anyway, like hearing damaging loud. SOME people genuinely think louder=better

However, the sound has to reach everyone in attendance. This is a problem if you only have 1 set of speakers and a large room but not so much if you have a rig set up with lots of speakers in different locations. Either way it is gonna be louder nearer the speakers in a large environment.

I always wear a pair of musicians ear plugs to concerts (yeah yeah cue the old man comments... i'm 21.) It gets rid of the loudness and you wouldn't believe the quality improvement of the sounds of the bands.

In your case the sound engineer probably just got too carried away and turned it up too loud unless it was a large park or field and they were trying to reach as far as possible.


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

[User] ELI5: How did we decide the value of a single unit, such as 1 watt or 1cm?

[Assistant]
'We' didn't, someone did once and it got popular. Often the popular unit was at least a bit reworked later, like the second, but still much the same.

Most units are defined in terms of other units. A Newton, for example, is 1 kilogram times 1 metres per second squared.

The 'base' units tend to be fairly arbitrary. Someone just decided something. The kilogram, for example, is based on the 'prototype' kilogram object. That prototype is, by definition, 1kg in mass.

As long as people reasonably agree on it being the base unit it's all good.


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

[User]
Is the Pauli Exclusion Principle a force?

If the exclusion principle is what keeps white dwarfs together, but has a threshold, then why isn't it considered a force?

[Assistant]
It's not a force in itself. The principle gives rise to degeneracy pressure, where you have to input energy into the system to further compress it by raising the energy levels of your particles.

The force itself is whatever the force is that results in those energy levels.


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

[User]
How do you reach out to a former professor for casual contact, If at all?

Taken from a previous post of mine:

I had a really wonderful professor a few semesters ago that really changed my perspective about life. In private she taught us so many life lessons and Im so grateful to have had her as my professor. I miss her.

Now today:

I was thinking maybe I should reach out, Im not really sure how. Some professors have stated professors like keeping in touch while others dont.

Any tips for effective communication here would be helpful!  Or general tips !

[Assistant] Email her.  Professors absolutely LOVE to hear from students like you.  Its a hard and often thankless job and what makes it 100% worth it is those (for me) rare moments when we see we can make a genuine difference to someone.


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

[User]
[Marvel] how were wolverine's claws tempered? Or sharpened?

So,  we know the adamantium was in liquid form when it was grafted to wolverine's skeleton.  But in order for any metal to be durable- hard enough to hold an edge,  flexible enough not to be brittle,  etc.  So my question is,  how did the weapon x program accomplish this after they injected the liquid metal?

Secondly,  how did they shape and sharpen the blades?  And how does logan hone the blades?

[Assistant]
They accomplished it by pouring into a mold that was around wolverine. The process binded it to his bones, but the claws were bound to bone-claws at the base but also molded to be that shape, which is a good balance of practicality and actually fitting in his hand/wrist.

It doesn't need sharpening. True adamantium is indestructible. It's not a regular metal in Marvel. It is actually impossible to destroy or deform it (outside very powerful magic) once the liquid has set. The molds for the claws were shaped to make a very sharp edge, and so the claws will forever be that sharp.


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

[User]
[MCU] Why does Thor bother being an Avenger. It's not even his world

I understand recovering Loki's sceptre would be important to him but I guess he could do it by himself anyway.

[Assistant]
In the MCU, all of his Avenging has been Thor dealing with an Asgardian problem.  The problem just happened to be happening on Earth.

- Thor 1 was about Odin sending him here to learn humility.
- Thor 2, he was on Earth because that's where the convergence was centered.
- Thor 3 didn't even involve Earth.
- Avengers 1 was about stopping Loki
- Avengers 2, he was primarily interested in retrieving Loki's sceptre.
- Infinity War he went to Earth because that's where Thanos was.


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

[User]
[The Mummy (1999)] Why would the Medjai punish Imhotep with a curse that can make him all-powerful?

So in the movie, the narrator exposits that the Medjai intervene in Imhotep's attempt to resurrect the Pharaoh's mistress and stop him just before he can complete the ritual, and as punishment, they subject him to the curse of the Hom-Dai, which the narrator said had never been done before because the curse is so cruel that Imhotep was the only one up to that point to be sentenced to such a harsh punishment. Makes sense. After all the man did commit regicide and attempt to use black magic on sacred ground. But then the narrator exposits that the Medjai take extra precautions to ensure that his sarcophagus is secure so as to ensure that he cannot be risen from the dead, because if he is, he will bring with him the ten plagues of Egypt, and be nigh-invincible.

Why on earth would they sentence Imhotep to a punishment where resurrecting him from the dead would mean he'd come back with godly powers to try to resurrect the Pharaoh's mistress again and then go on to conquer the Earth? Who's bright idea was it that this would be a great punishment for the most heinous of crimes? How could they ever be certain that they could prevent him from being resurrected for the rest of eternity?

[Assistant]
The ritual makes them live forever, which to Egyptians was a curse beyond all others. No eternity in Afterlife, no peace, never to see the ones they love again. Just darkness. This is, assuming, no ignorant fools dare speak the ancient spells that can bring them back to life. In which case their presence is such an abomination they bring ruin to the world.

The Medjai of ancient times never expected people so foolish to speak words they don't understand the gravity of.


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

[User]
ELI5: How to convert black and white photos to colour

How does it work? Do the black and white shades have coloured counter parts?

[Assistant]
You colour it in by hand (usually in photoshop) by adding colour on top of the black and white shading.

It's like painting over a pencil sketch with watercolour paint, you still see the pencil shading underneath but the watercolour adds colour on top.

To get it looking realistic you sometimes have to lighten or darken bits too as some colours in B&W photos are too light or dark, and the whole thing takes time and skill to do right.


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

[User] What's neoliberalism?

[Assistant] Neoliberalism is all about free trade. The basic idea is that you open all markets and completely abolish market regulations, such as workers right, work hours trade sanctions etc. The market will then choose demands and supplies based on the actual need of the consumers. In doing this you allow a truly self defined market which regulates and maintains itself with no government assistance.


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

[User]
CMV: Calzones are way better than pizzas.

So for the past 5 years Ive worked at a New York style pizza restaurant. I started off as the dishwasher and worked my way up to the kitchen and Im now one of the head cooks. If there is one thing that Ive learned over the years, is that calzones for so many reasons IMO are just better than a pizza.

For starts, the portion size is perfect. Its super easy to consume too many slices of pizza, but a calzone is perfect because its always one ur plate in one portion. And 9 times out of 10 itll leave you full. Vs a pizza were youll only realize you were full on youre 5th slice, you sit there and realize I was full 2 slices ago.

Next up is sauce dose. On most Northern American inspired calzones, you can control the sauce dose. Sometimes when eating I want a little sauce, or I want a lot of sauce. With a pizza you cant control that, you just get what you get. With a calzone you will always be able to control the amount you want.

Lastly, itll stay hot for a long time. Calzones are a pocket of cheese ricotta and other stuff. It traps all the heat. Vs a pizza thats got a ton surface area for heat to escape.

I rest my case.

[Assistant]
OP, you're ordering food for a party. You don't know how exactlu many people will show up, how hungry they are, or their preferred ingredients. You also don't want to be wasteful and are fine with leftovers.

What are you ordering, some 'za or a bunch of calzones?


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

[User] ELI5: The difference between 720i to 720p, 1080i to 1080P?

[Assistant]
720i first of all never existed.

The i and p stands for interlaced (i) and progressive (p) scans.  The interlaced scan does every other line on one frame then goes back and does the opposite set of lines on the next, progressive starts at pixel lines 1 and goes through to the last pixel line before going back to the beginning.

The difference is the amount of information being generated by the TV each frame, a progressive frame rate is a much larger amount of data, thus the reason why most networks use 720p/1080i, because this is the same amount of data being broadcast, it's just being displayed differently.


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

[User]
ELI5: Why are so many people afraid of cockroaches although they are relatively harmless?

I know that they're filthy and all, but what is it about roaches that genuinely terrifies people and evokes such an instinctive response?

[Assistant] Roaches tap into our evolutionary fear of dirty things. Humans like to control their environment, but roaches are very difficult to kill. They can adapt quickly to most poisons and they can survive on almost anything.


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

[User]
ELI5: Why Tesla's new power wall a big deal.

How is Tesla's new battery pack much different from what I can get today?

[Assistant]
For people with solar panels, it lets them store the excess energy and use it themselves rather than selling it back to the grid for pennies.

For everyone with variable usage costs, it lets you take power from the grid when it is cheapest (nightime) and then store it to use at any time you want basically meaning you always pay the minimum rate for your power.

For everyone long term, if these gets widely adopted, power companies can completely change the way they create power, and there will never be variable rates. And "theoretically/optimistically" power would get cheaper because power plants would be running constantly rather than stopping and starting.

Telsas power banks are better than what you can get today simply because they are for the most part a lot cheaper than current methods, and have programming built in so anybody can use them efficiently.


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

[User]
Is bent metal stronger than metal cast at an angle?

Why is it that metal gets bent into rounded arcs or right angles instead of cast that way?  Is it a strength issue or a money issue or what?

When I say cast i mean molten metal poured in a mold.  (sorry f that is not the correct word)

[Assistant]
Cold forging introduces new dislocations in the crystal structure of the metal which increase both hardness and strength. So a bent/cold forged bracket will be 'stronger' (it will deform plastically at a higher stress) than the unbent form of the same initial crystal structure. Cast metal and hot forged metal should have similar strength to the unbent version given the same cooling times.

However, after production, most metals are heat-treated to certain specifications. This means the initial production of if it does not matter very much since you plan on controlling the final crystal structure through heat treatment.

The cost element is higher for casting because molds are incredible expensive and you would need a different mold for each unique piece. This is why most companies just cold forge blanks and then heat treat. Cold forging means many different products can be made without incurring added mold costs.

tl;dr cheaper to cold forge the metal and heat treat it rather than cast it since they will have same strength in the end due to heat treatment.