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

[User]
ELI5: I saw a post about college tuition being $152 in the 70s, and inflation means thats around $700 now. What about income rates?

I know college is severely overpriced, but wouldnt it be a lot harder to reach $152 back then If that was the case? This is without research, but werent wages super super low?

[Assistant]
The median income of American families in 1970 was $9,870 and minimum wage was $1.45 per hour.  Average annual tuition at a public university in 1970 was $405, and at a private university $1,792.  This means a year of public uni tuition was 4.1% of median annual income, and a year of private uni tuition was 18.1% of median annual income.  It took 280 hours working at minimum wage to cover public tuition (about 7 weeks of full time work), and 1,236 hours to cover private school tuition (about 31 weeks).

The median income of American families in 2020 is $78,500, and minimum wage (federal) is $7.25 per hour.  Average annual tuition at a public university in 2020 is $11,260 for in-state students, and at a private university $41,426.  This means a year of public uni tuition for in-state students is 14.3% of median annual income, and a year of private uni tuition is 52.8% of median annual income.  It takes 1,553 hours working at federal minimum wage to cover public tuition (about 39 weeks of full time work), and 5,714 hours to cover private school tuition (about 2 years and 39 weeks).

So while wages and income have indeed risen in the past 50 years, tuition has increased much, much faster.  Families must now set aside nearly 15% of their annual income to cover a single in-state college attendee's tuition at an average public college, whereas 50 years ago they could set aside 4% to cover the same thing.  And that's just tuition - housing and other costs at uni have also increased dramatically.  And given the even more dramatic increase in private uni tuition, such schools are simply out of reach to most families without massive financial aid packages.


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

[User]
[Star Wars] Why do people in the Star Wars universe think that the Jedi are myths or use the term "the legends say..." when there was an entire branch of the government run by Jedi less than 20 years ago?

Is 20 years even long enough for something to fall into legend?

[Assistant]
Less than 10,000 jedi at their height of power. That's barely anything in a galaxy of trillions to quadrillions. Jedi didn't leave the core republic systems often and rarely visited planets that weren't of importance to the republic. Palpatine ran a massive smear campaign and destroyed nearly all evidence of the Jedi after order 66.

Not everyone knew what jedi were or did beyond drunken tales told by spacers in bars even at the height of their power. They were reclusive and rare to the point that even most senators on coruscant had never met or seen one. Let alone some hick kid on the edge of civilization.


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

[User]
Why can solar panels only convert roughly ~20% of sunlight received into energy? What will it take to increase this percentage?

I recently learned that only ~20% of sunlight received is converted into useable energy. Why is this? What will it to take to receive more energy from the solar cells?

Thanks!

[Assistant]
Check various science sites - there is a lot of research into improving the efficiency.  There are some solar cells that have achieved over 40% efficiency (although these are still pretty expensive).

BTW, even though 20% seems low, did you know that a gasoline engine only delivers about 15% of the energy available in the gas?


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

[User]
Do waves with lower frequency travel further than waves with higher frequency?

What does frequency have to do with attenuation over distance? Does it depend on the amplitude or energy of the wave? Googling about this quickly got me more confused. What is the difference between Energy, Power and Intensity of a wave? How do these relate to the frequency and amplitude and more so the attenuation of a wave over distance?

EDIT: I was thinking about electromagnetic and sound waves when I posted this question. But I would not mind learning about ocean waves as well :)

[Assistant]
Subject question:
Low frequency do travel further than high frequency on earth because the high frequency wave lengths are more easily absorbed by the molecules in the air.

First Comment question:

Attenuation is the gradual loss of energy which will in most cases happen over distance.  This has to do with what absorbs the particles riding on the specific frequency, as well as what has a multiplication effect (see resonance).

Next question:

More amplitude, more energy, means more energy to be lost, means it can travel farther before it loses all of it's energy generally speaking.

Third and Forth question:

Energy versus Power versus Intensity versus Amplitude, these terms are probably confusing because in specific in applications the variants of the term mean different things but certain things are understood.  For example, sound equipment, most people who talk about Power, are talking Power(RMS) not just Power(Peak to Peak).  In addition depending on the industry certain terms are or are not used.  In general these are all talking about the same thing though.  Amplitude = Energy = Intensity = Power, and so this means the wave will travel farther in general.


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

[User]
ELI5: Why are artists like Van Gogh and Picasso famous? What makes great art great?

This is coming from someone with no education in art or art history beyond high school classes. I understand that art that's in museums takes a huge amount of talent. What I don't understand is what makes some of the most famous paintings/art pieces more celebrated than other works.

I'm also not that great at analyzing pieces of art. What is the meaning behind paintings like The Scream or Starry Night or the Mona Lisa? Why are those images so powerful?

[Assistant] A lot of famous art can only really be appreciated if you understand the time it was created in. In reality the Mona Lisa (for instance) is just a portrait of a woman. But if you see it in the context of the time it was created, it combined lots of different techniques that meant that it was a revolutionary and brilliant artwork when it was created.


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

[User] ELI5: How do single celled beings "know" what they're supposed to do/"want" to do?

[Assistant]
I personally like to think of simpler life forms as like tiny computer programs. Their DNA is their "source code," and the cell itself is the hardware it runs on.

So a tiny cell 'knows' to avoid being eaten by larger cells because it's "source code" told it to build receptors on its cell membrane that are programmed to detects certain nearby chemicals, and one particular chemical triggers a flight response.

Other chemicals do the opposite -- they indicate a source of nutrients, and cause a chemical chain reaction that makes the cell move toward the food source. Once in range, various other mechanisms begin to operate, drawing in the food and disassembling it for processing.

But everything was built by following the template in the DNA, and certain triggers result in certain behavior.


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

[User]
Alternative career paths for Ph.D?

What are some alternative careers outside of academia that those with a Ph.D in science (specifically ecology and evolutionary biology) may enjoy? It seems all too often that academia is promoted as the only option for those that stick it out in doctorate programs.

[Assistant] There is a huge amount of attention on this right now because of how tough the academic job market is. Tons of PhDs are starting consulting companies to help other PhDs get non-academic or "alt-ac" jobs. Check out "Beyond the Professoriate," "Jobs on Toast," and the Twitter chat #withaPhD.


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

[User] ELI5: Why is it specifically called "radio"activity, when it most often is produced by waves other than radio waves?

[Assistant]
>radioactive - 1898, from French radio-actif, coined by Pierre and Marie Curie from radio-, comb. form of Latin radius (see radiation) + actif "active" (see active).

>radiation -  mid-15c., "act or process of radiating," from Middle French radiation and directly from Latin radiationem (nominative radiatio) "a shining, radiation," noun of action from past participle stem of radiare "to beam, shine, gleam; make beaming," from radius "beam of light; spoke of a wheel" (see radius). Meaning "rays or beams emitted" is from 1560s. Meaning "divergence from a center" is 1650s.

>radio -  "wireless transmission of voice signals with radio waves," 1907, abstracted from earlier combinations such as radio-receiver (1903), radiophone (1881), radio-telegraphy (1898), from radio- as a comb. form of Latin radius "beam." Use for "radio receiver" is first attested 1913; sense of "sound broadcasting as a medium" is from 1913.

So both of them come from the idea that the energy is beaming out.


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

[User]
[WH40K] What's with all the skull imagery in the Imperium?

Seems a bit grim (yeah yeah grimdark I know). They've got that double headed eagle but then many of their units have skulls as their symbol (Space Marines, Inquisition, Imperial Guard, Adeptus Mechanicus)

[Assistant]
The skull represents the sacrifice that maintains the Imperium of man and it represents humanity itself.

It is important to make the distinction: it is a human skull, not some Xenos they killed and used as a trophy, human.

It is used to show that at it's core, the human being is perfect. Skulls are used to display that even in death humanity is superior to any xenos. It also helps making the people of the Imperium accept death as a natural part of life, which makes it easier to lay down your life for humanity and it's Emperor.


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

[User]
[D&D General] I think my party has been charmed

I'm a squire to a well known group of heroes that are known for their heroic deeds. Everything was going fine until one of our fighters was burnt to a crisp during a recent fight with a nasty dragon.

It's been a couple weeks of mourning but something strange has happened lately.

 Two days ago we met this suspicious fellow who asked to join our party, I thought it was a strange request, but even stranger was the fact they said yes! They even gave him the gear of our recently deceased comrade!

Everyone seems to implicitly trust this man and I'm thinking some foul magic is involved, something powerful enough to beguile our wizard.

Now I'm no fighter but I was wondering if any of you had any advice on how to cure my party of this charm?

[Assistant]
You must believe in Destiny, and the workings of the various Gods. Your adventuring party has been blessed with a replacement, who happens to fill the void of your deceased comrade almost perfectly. This is a sign from the Gods, a Divine Miracle.

Speak to your party's cleric. Learn what they did, that at times the Gods reward adventurers with what may seem to be a completely impossible act. Here, you have found someone new to aid you in your journey, who can use the gear of that poor, departed Fighter.

To reject what is clearly an offering from the Gods would bring ill omens upon your adventuring party. Tis best to ignore the whole thing, and perhaps even pretend that the new fighter has been there all along.


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

[User]
What are the best sites to search for economics papers?

I don't have institutional access and I was wondering if there were any sites like Google Scholar but exclusively for economics papers?

[Assistant] Still just Google scholar. When you get to a gated paper: search regular google with the author's name + paper title. They probably have a free copy up on some personal page (e.g. university bio, personal CV, or wherever).


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

[User] Why do banks issue bonds when they can borrow funds at the lowest rates from the central bank?

[Assistant]
The central bank is typically the lender of last resort, and it does that in part by ensuring it is the *most* expensive option.

Companies issue bonds because they see it as the cheapest option to get the cash they need. Banks are no different.


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

[User] [Harry Potter/Aliens] We know there is a genetic component to magical ability so what might happen if a Facehugger was somehow able to implant a wizard?

[Assistant]
There seems to be a mental component to magic aside from just having "the magic gene".

All the creatures that developed some kind of magic (giants, goblins, house elves, wizards) are sentient, capable of rational thought. Other magical creatures don't seem to control their magic consciously, but rather instinctually.

An alien with the magic gene would have neither sentience nor the instinct to use magic, so it's probable they would not express magic even if they had the gene.

They would basically be squibs.


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

[User]
Why doesnt the govt borrow money at the treasury bond rate and invest in an index fund with a higher average return?

The interest on a yearly treasury bond is something like 7% while the S&P500 has an average return of 10.7% over the last 30 years. Shouldnt the federal government make use of this roughly 4% difference?

This is probably a dumb question but I appreciate any responses!

[Assistant]
There are a few reasons for this. First, the government owning equity is very taboo, and represents a line that many argue should not be crossed. If there was a guarantee that the government would purchase equities, even in the form of an ETF, there would be a price floor created and moral hazard would be introduced. Therein, a company could act haphazardly as it would be assured that as long as it stays in the S&P500, their stock price would remain inflated.

Second, the government has no need for this. The purpose of a government is not to create profit.


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

[User]
ELI5: Why the abbreviation of ounces turned into oz. when there is no letter Z in it?

Where did the letter z come from?

[Assistant]
"oz" came from the Spanish "onza" -- meaning ounce. The words "ounce" and "onza" come from the Latin "uncia" meaning "1/12th", because an uncia was 1/12th of a libra (pound). For that matter "lb" for pound comes from "libra".

In the avoirdupois system of measures, there are 16 ounces to a pound rather than 12.


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

[User]
[Star Wars] Why don't Jedi just Force Press the button on a Siths lightsaber when fighting?

My boyfriend and I were talking about it, and I thought first it was because it was too small, but then remembered Master Yoda's words, "Size matters not". So, why not? Or, if it's just for the matter of fairness, then why not the inverse- a Sith turning off a Jedi's?

[Assistant]
Well, for one, the Sith's finger.  Most Jedi and Sith design their sabers to be on while a trigger is held. You notice how lightsabers turn off when they get dropped?  That's usually why.
So there's not really an 'off' button for one to use the Force to push in the first place.  You could try to get your opponent's hand off the activation trigger, but if you have the power to do that you might as well just yank the saber away entirely.  Folks do try for that pretty frequently.


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

[User] Why do materials like some metals with lower heat capacities than water, require so much more heat to liquify?

[Assistant]
They don't actually.

Water melts at 273K, iron at right around 1800K

For one gram of water  go from absolute 0 to fully melted at 273K requires around 600J to heat the ice to its melting point, and then close to another 350 to melt completely for around 950J

For one gram of iron to go from absolute 0 to its melting point of 1800K, it requires around 810, then another 250 to melt to liquid. 1060J to melt the iron.

Now let's talk about why it **seems** to take so much more energy. The most obvious is the fact that 1800+K temperatures are not as common as 273+K temperatures in the universe. And especially here on earth.

Another reason is due to a nice little thing called black body radiation. By the time iron gets to its melting point, it's throwing off so much energy as electromagnetic radiation (light) that it gets harder and harder to pour enough energy into it to overcome this loss. And of course finally there's conductive and convective cooling. Also known as environmental cooling, where it's losing energy to its much lower temperature environment via air, or maybe even worse, water. Overcoming that cooling requires MUCH more energy.


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

[User]
[Star Wars] Are the Sith inherently evil dicks?

Like, I get the Dark Side is all about power and selfish desire, but why does that seem to always manifest as "I'm gonna kill *all* of the people"?  Why have none become an incredibly powerful hero, who just wants to bask in glory and admiration(i.e, saving people for the praise and recognition rather then to actually save them) instead of becoming a lulz-evil dick head?

[Assistant]
The dark side is not evil by itself, and technically the Sith code doesn't tell them yo be evil either.

However, the dark side *is* bestial and predatory in nature, and **will** fundamentally alter someone using it so that actions that are considered evil are completely acceptable.


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

[User]
Why are some people blonde when they're young and their hair gets darker with age?

Do we know the physiological mechanisms/inheritance? Does all hair get darker, but it's more obvious if you start blonde?

[Assistant] People with genes that code predominantly for brown eumelanin are the ones whose hair is most likely to darken with age. This is because although they have the genes coding for brown eumelanin production from birth, these genes are not expressed to their full potential in early life.


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

[User]
CMV: Wallets in the front pocket only makes sense

So, I've had this long standing confusion when it comes to wallets. I know a number of people who keep their wallets in their back pocket. I've never understood this and think it's illogical. When looking at where we keep other normal pocket items such as phones, gum, keys, etc we keep them in our front pocket generally. We wouldn't want to damage the phone by sitting on it too hard, squish the gum, drive a key into our butt, and the same concept applies to a wallet. The biggest thing though is simple comfort. Front pockets tend to have more room to comfortably fit items. They also tend to experience less constriction than the butt pocket a the majority of the space in the front pocket lies on the thigh. The butt is constantly constricted. Additionally, there is no conceivable way where having a lump under your rump when your sitting makes sense.

[Assistant]
>They also tend to experience less constriction than the butt pocket

I have experienced the exact opposite, at elast with the slimmer jeans.

The butt pocket is usually sewn onto the fabric, where it doesnt compromise the form, while the front pocket is set inwards where the wallet is pressed into your tigh at every step, making it painful or even impossible to walk in a particular slim pair of jeans.


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

[User] Were protohumans able to reproduce year round, or did they have seasonal mating? How far does this trait go back on our evolutionary tree?

[Assistant] Well, pretty much all monkeys reproduce year round, so it's probably a reasonable bet that our most recent common ancestor with new world monkeys probably did too.  That puts us at least at 40 million years.  That said, year-round reproduction in mammals probably more a factor of climate than lineage.  If you live in the tropics (like many primates do), there aren't major seasonal variations that you could reproduce according to.


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

[User] [Marvel] Could I, a US citizen, ever emigrate to Wakanda?

[Assistant] Yes, but Wakanda has very strict immigration policies. You'd need to be an expert in a field capable of adding something to Wakandan society. So, talented artists, scientists, teachers and the such could possibly immigrate there. Alternatively, if a Wakandan married you, as many of them attend foreign universities, it's possible that you could return with your spouse as a permanent resident.


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

[User] [MCU] If I blindly/unknowingly fell into Thor's hammer, groped around and grabbed it for stability, could it move (given that I'm not trying to pick it up but that my inertia from my fall might cause me to move while grabbing it)?

[Assistant]
It's been shown fairly clearly that MCU Mjolnir will remain stationary and unmoving unless Thor wills it or a worthy wielder picks it up.

In the very first movie for example, Thor just put it on Loki chest - Loki clearly didn't want to wield Mjolnir, he just wanted to get away from it, but it still pressed down on him and didn't move.

There's really no caveats here - if you grab it for any reason and you're unworthy, Mjolnir won't budge.


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

[User]
Why is high-frequency sound easier to block than low frequency sound?

I noticed that if you are standing far away from a sound source, that the high freq. notes tend to dissipate more rapidly than the lower freq. notes. Also, if you play music and step outside the room, only parts such as the bass guitar carry through the foundation. Why is this?

I remember reading somewhere that sound attenuation is quadratic with frequency, but I don't know why.

[Assistant]
Low frequency means longer wavelength.

High frequency means shorter wavelength.

To block an oscillation, you need an obstacle (a screen, a damper, a block) that is larger than the wavelength, otherwise the wave will simply go around it by the phenomenon of diffraction. If the obstacle is much larger, diffraction gets smaller and smaller until it becomes unimportant.

Even if there is no diffraction, as in a cork in a pipe, it's still a good idea to make the cork bigger than the wavelength, otherwise it gets pushed and pulled by the wave and keeps bobbing back and forth with it. If the cork is larger than the wavelength, the wave gets reflected or absorbed more easily (the obstacle doesn't move as a single unit with the wave, but instead it starts to absorb it internally).

Sounds complicated but there's a simple way to visualize it: An ocean, the water is pretty calm, small waves. A cork floating on it. An aircraft carrier floating next to the cork. Ocean waves are much bigger than the cork, but are much smaller than the battleship. Which object deflects the waves, and which one lets them pass unscathed?

However, during a huge end-of-the-world hurricane, the waves are so large that become comparable with the carrier, which then cannot deflect them anymore.

Please note that the analogy is not perfect. Large ocean waves carry more energy compared to small ones, whereas long acoustic waves carry *less* energy than short ones. Yet both small ocean waves and small acoustic waves are deflected or stopped by larger obstacles. This shows that the main factor here is not the energy, but the wave length.

When you go outside the house, you keep hearing the bass because the wave is so big, the whole building is moving with it as a single unit, so the wave just goes through it like an arrow through paper. But the high frequencies are much shorter than, say, the wall thickness, so the wall doesn't move with the wave as a single unit - instead, the wall starts to compress and expand internally, under the force of the wave, and so the wave is dissipated inside the wall.

There's also reflection on the walls inside the room, and the idea is basically the same.

TLDR: Wave physics.


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

[User] [Last Airbender] Badger moles are earth benders and fly bison are air benders, what animals are fire and water benders?

[Assistant] Dragons are fire benders and the moon is a water bender. Yeah, water benders learned from the friggin moon somehow. Aside from the OGs some other implied benders are the unagi (giant sea serpent that spits water) and flying lemurs like Momo.


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

[User] ELI5 Why aren't we making plant based fuel from eucalyptus trees instead of Fossil fuels?

[Assistant]
There are only so many eucalyptus trees that are the right types to produce biofuel and it takes a ton of work to transport them and then convert them into usable fuel (and only certain kinds of fuel at that). They can't grow back quickly as well, so once you cut down an area you have to replant it and then wait years for it to regrow. So the cost is going to be very high, even if it's better for the environment.

Fossil fuels are a lot more convenient. It takes a lot of money to set up an oil well, sure, but then you're going to get tons and tons and tons of oil out of it with very little work, and that oil can be processed into many different fuels using refineries that we already have built and invested in. And oil companies aren't going to replace all that without a really really strong business reason.

Fossil fuels are going to run out at some point, but for now they're still cheaper and more flexible than most biofuels.


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

[User]
Is the identity of dark matter completely unknown, or is it likely known, and we're just waiting for proof and scientific consensus?

For example, if dark matter is bread, then it's not completely unknown (but still surprising), and we're just waiting for someone to prove it.

[Assistant]
for what evidence and observations we have so far, the dark matter does not participate in electromagnetic interaction, only in gravitational one. that means it does not interact with photons and thus does not emit or absorb light. and that is why we cannot see it at all. given the fact the most of our knowledge about the space and the things from afar come through seeing emitted or reflected by various objects light, we can only speculate about the nature of dark matter.

the only way we get our knowledge is gravitational interaction. when the dark matter cloud tugs on a near star we can see the star is deviating from its supposed path and make some implication on the mass and distribution of the object that makes the star move in the way we see it moves.

maybe when we have starfaring laboratories we'll get close to dark matter and actually try to scoop it in a flask.


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

[User] [ASoIaF] Exactly how powerful was Valyria at its height?

[Assistant]
It controlled most of known Essos, but wasn't a really centralized state. The Freehold stretched from the Dragonstone of Westeros to the Bone Mountains in the east. There were many opposing houses so strife was fairly common. They definitely had powerful magics, many, many slaves, and devastating dragons, but the constant warfare and rivalry really prevented anything we would recognize as a single, powerful entity.

The Valyrian Freehold is more like a bunch of city states that happened to span much of the known world, who held their territory by might of their dragons.


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

[User] Why is the specific heat capacity of an object dependant on its temperature?

[Assistant]
There are some *very* special cases where it's not, for example a classical monatomic ideal gas and a Dulong-Petit solid.

However in general, dE/dT is not a constant; there's no reason why it should be.

Different degrees of freedom "become active" at different temperature scales. For example vibrational, rotational, and electronic excitations of molecules.


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

[User] ELI5: Why people are so happy to get a Tax refund? Doesn't that mean the government has taken more money from you than they should have?

[Assistant]
It means you gave the government an interest free loan for 12 months.

But for people who don't keep rigorous track of the labyrinthine tax code (i.e. everyone) it's hard to estimate what you'll end up owing and deduct accordingly.

So it's nicer to learn that you've overdeducted and get a refund.  The alternative is much worse for most people.


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

[User] [Guardians of the Galaxy] Are the Xandarian humans (ex. Nova Prime, Dey) biologically identical to Terran humans?

[Assistant] Nope. Technically, they are biologically distinct from Humans, but they share a LOT of similarities. Unless you are some sort of medical professional or biologist, chances are those differences mean virtually nothing to you; you can still enjoy sex together, enjoy similar foods and drinks, compete mentally and physically without distinct racial advantages, and it appears that our overall psychologies are very similar.


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

[User] ELI5: What are all the people doing on the floor of the major stock exchanges, and why can it not be automated/done from an office?

[Assistant]
These days it is automated and they are largely gone, except some will be there to look at their terminals.

If you go to the NY Stock Exchange, the place is filled mainly with journalists and tv studio set ups to report on financial news and help report on new stock offerings.

But these days the significant majority of trading is done electronically, and a large portion of that electronic trading is done through algorithms, without much (sometimes without any) human input.

Prior to the internet, people on the floor of stock exchanges would do the actual trading of shares.  Rich Bob wants to buy $5 of shares in Coke, so he calls his broker, who receives the order, and sends it as quickly as possible to a man on the floor of the exchange who begins advertising that he is wanting to buy shares in Coke.

Smart Harry told his broker that if anyone tries to buy Coke today, he will sell them his shares in Coke at $1 a share.  So Harry's broker see's Bob's broker and they agree to the sale and register it with the stock exchange regulators.

The brokers take their commission of a couple cents per share, then go off to share a tipple, check out the broads, and definitely not insider trade.


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

[User]
ELI5: If the cells in our body keep renew constantly the why people are getting old?

ELI5: Aren't if the loop keep going on then we suppose to be young forever as long as the body getting nutrients and energy?

[Assistant] To renew themselves, they copy themselves. Each time they make a new copy its just a little less perfect than the last one. An analogy would be making a photocopy of a photocopy of a photocopy until its no longer a readable image.


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

[User]
Does the probabilistic nature of quantum mechanics extend to non-quantum phenomena?

My understanding of this topic is very basic, but from what I can gather, everything (?) at a quantum level is described in a probabilistic sense rather than a deterministic one. Not because of measurement error, but for more fundamental reasons.

My question is this: does the uncertainty we observe in quantum mechanics manifest in any way in non-quantum phenomena? Are phenomena at a non-quantum level deterministic, as far as we can tell?

[Assistant] What happens as things go from one to a few to many particles is that the total uncertainty for the system goes down relative to anything you would want to measure. So, simplistically speaking, the total amount of momentum could go up with the total number of particles, while the uncertainty of the momentum goes up much more slowly. By the time you get to macroscopic sizes, in the hundred of trillions of particles and more, the uncertainly due to quantum effects is smaller than the error of any measurement you could make. So for all practical purposes these things are deterministic with respect to quantum uncertainty. However, there are other things that determine uncertainty, such as an inability to accurately model large systems due to an inability to get all the details correct, hence the uncertainty in weather forecasting.


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

[User] [MCU] Why did the Space Stone violently reject Red Skull, but was cool with Thanos and Loki?

[Assistant] Red Skull is just a modified human isn't he? If so, he's physically and magically inferior to both Loki and Thanos. They clearly outclass him. They also both knew what they were about to handle, and took whatever mental precautions were necessary to do it safely.


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

[User] eli5 In movies and video games and stuff, characters get stabbed in the gut all the time and this usually causes them to puke up blood instantly. People have told me this is realistic and have tried to explain how it happens but I never get it. How does a stab cause blood to come out of their mouth?

[Assistant] Your stomach gets punctured and fills with blood. Usually a stab wound releases a lot of blood internally with veins and arteries being cut. Things inside your body are usually pretty well contained, but once things get cut, blood can flood anywhere.


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

[User]
[Tolkein] Are there many people in Middle Earth who are "in the know" about Gandalf?

He tries to pass himself off as a wise old man, and maybe he can explain away his magic sometimes, but various kings must know he was advising their grandfathers when they were children and hasn't aged a day. Does anyone know the full extent of what he is, and if not, what do they *think* he is?

[Assistant]
Just about every king, court official, and other important person seems to know exactly who he is.  They may not know the full extent of his power, but they know he's a wizard and he's been around for far longer than he should be and that he's knows a lot more than he's saying.

The common folk don't know any of this, however.  To them, he's just some old guy.


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

[User]
[DC] Could all of the weirdness that makes superheroes and villains on Earth happen on Krypton?

If it didn't blow up, obviously. Everyone is basically just normal humans when on Krypton, right? What if some Krypton scientist gets hit by lightning in that exact right way? Would they become connected to the Speed Force? Some Krypton child's parents are shot in front of him and he becomes obsessed with... space bats. A Martian baby lands by a kindly Krypton farm couple who raised him as their own.

I guess what I'm asking is: is Earth special? Or could all the weird crap that happens here happen on Krypton, given the time?

[Assistant]
Some of it could. There were vigilantes, and - at least in some continuities - supervillains, who were sentenced to the Phantom Zone. There were sorcerers and gods.

But Earth is a dimensional axis, houses the Life Entity, and has the Metagene seeded in it's population. And it may or may not be the nascent Fifth World. And it's neighbours to the Martians, an immensely powerful race. And it's the most "emotionally rich" planet in the galaxy, according to Sinestro Corps War. And Superman has some sort of dimensional archetype thing going on, so it's cosmically important he gain his powers, according to Final Crisis, and all the other Supermen are on Earth.

Oh, and Rao, the sun god, hates you. Personally.


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

[User]
ELI5: if cheese comes from milk, how do we get so many types of cheeses?

I understand that there's feta that comes from goats milk,  but things like Monterey Jack,  and cheddar and even sub sets like white cheddar; it's all milk but how do they make so many different types of it?

[Assistant] Different cultures added to the milk make it form slightly different curds. Changing the salt content will alter the flavor too. Cheese is basically a recipe like anything else. If you take flour, baking powder, milk, and eggs you can make all kinds of stuff even though the ingredients are all the same.


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

[User] [Star Trek] Is the Borg collective just a tool to coordinate them to fight better, or is there truly a "democracy" in their hivemind? Would they change their tactics if a majority of drones "voted" to stop assimilating other species?

[Assistant] It's not as if drones have any individual will that contributes input to the collective.  Rather the collective is a single mind running on a wide array of equipment that is in part made up of drone brains.  It's not even possible for a drone to want to stop assimilating or to want to change policy of any kind.


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

[User]
ELI5: When I'm cooking, why does stirring the pot slow the onset of boiling?

And likewise, once something is already boiling over, why does blowing on it make it stop?

From what little I remember of the high school physics class I nearly failed more than half a decade ago, it seems like stirring or blowing would be adding kinetic energy, which should increase/encourage the boil, shouldn't it?

[Assistant]
Yes, stirring adds kinetic energy, but nowhere near enough to make an appreciable difference in temperature.  Water takes a LOT of energy to heat up, more than you would ever be able to achieve with a spoon.

As for why it slows the onset of boiling, it doesn't really, it just makes it look that way.  When you have a pot on the stove, the water on the bottom is very hot compared to the water at the top.  The water on the bottom will start to heat up and boil, but it immediately cools when it rises up into the higher water.  That's why in early boiling you see little bubbles come up off the bottom of the pan and then immediately disappear.  When you stir the water, you are equalizing the temperature inside of the pot, so instead of warm water with a very hot bottom, you now have a pot of water that's evenly warmer.  You won't see the bottom "boiling" but you're not really changing the time it takes to get the whole pot boiling by all that much.


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

[User]
Who owns conferences?

I just started my PhD, and thus, was just exposed to the world of conferences. I'm surprised by how expensive they are. It seems like a very good business with excessive profit, which means that it is a good business opportunity, better come in before the market is saturated. So who owns the conferences? I'm just curious, who are the business savvy individual who spotted this opportunity and seize it?

*****************

Given that I'm new, it seems to me that this is how the conference business work: correct me if I'm wrong. People don't come to a conference out of their own pocket, so they don't care about price. The organization pays. The organizations have very deep pocket, so they are less sensitive to price. More importantly, they cannot afford not sending people to conferences, the loss they will get is even greater. Since the demand is high, and has big pocket, while the supply is currently limited, the price are not cost driven, but demand driven. Am I right?

[Assistant] The funding body typically owns the conference (this may be the same as the organizer, or it may not). When considering the price of attendance, you have to factor in costs like lease of venue (even if the conference is happening at a university, the university will usually charge a fee for using its space), catering, audiovisual and administrative support, as well as payments to speakers (academic conferences rarely pay presenters, but in industry this is quite common). In the end, $300-$500 per person in the developed world just covers these costs.


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

[User] ELI5: Is there any science behind why many people find the basements in their home to be creepy?

[Assistant]
Probably a number of reasons.

*They're underground*. Underground is for permanent storage, death, graves, and the Underworld. Satan/bolrogs comes from the ground. Hell is down, not up. Generally, us as humans have historically always associated things underground as being malicious.

*They're dark*. Basements are mostly completely dependent on artificial lighting. Humans don't like dark. Humans loose one of their senses in the dark and humans don't like not being aware of their surroundings.

*It's a place in your home where you don't live*. Another feature of basements is that a lot of them are purely used for storage. Thus it probably isn't meant to be cosy or inviting.

*Cold. Bugs. Damp*. These are all associated with basements and most humans don't like those things.


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

[User] ELI5: How come a remote with batteries that are almost dead, starts working when you slap it ?

[Assistant] The ends of batteries get oxidized of time. This causes a 'coating' that doesn't transfer current between the battery and remote. When hitting it, or just fumbling with the battery. The battery moves and reconnects with the metal that it transfers its current to in a different position. Which can help work around that coating.


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

[User] ELI5:Why do we have fear over something even though we know It is not real?

[Assistant]
The older part of your brain doesn't know it's not real.

The part of your brain responsible for fear, the amygdala, is very ancient. It's part of what people often refer to as the "reptile brain," and it evolved to help you avoid things that could hurt you. Even if the conscious part of your brain fully knows something is harmless (like a horror movie you are watching), the response by the amygdala, which is hard-wired, can often be powerful enough to override that.


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

[User]
eli5: How do they decide what the speed limit is for a road?

Basically the title. I'm curious what they do to decide. surely they don't just stick a random number on a sign and call it a day.

[Assistant] It depends largely on the nature and purpose of the road.  Things like width, straightness, slope, signage and surface influence how safe it is to use that road at speed.  Obviously you need to go slowly on a narrow, windy road if you don't want to accidentally leave it.  If you want a road to be fast, you need to make it straight enough that steering is easy and you need to make sure people have enough time, space and notice to react to whatever they're approaching.  The other thing is that you need to make sure the limit accounts for transitions onto other roadways or through areas of different usage.  A smooth transition between different speed zones is better than, for instance, letting a highway exit directly into a school zone.


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

[User] [Marvel/MCU] Can Thor be stealthy?

[Assistant]
Well, he certainly managed to go (mostly) unseen while sneaking around Asgard when he went back in time. And he had even put on a few pounds at that point.

He's probably not great at it, but he seems at least basically competent.


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

[User] ELI5: How does "Login via Facebook/Google/etc" work? How can it be secure to give away my credentials to random sites?

[Assistant]
Your credentials are never sent or known to the random site, but your user info is. This is how it goes:

1. You want to login to random site XYZ and that means you want to prove your identity to XYZ (this process is called authentication)
2. When you choose Login via Facebook/Google/etc you are choosing them to prove your identity for you (because they already know you, you are registered there). The way Facebook/Google manages to prove your identity to XYZ depends on the protocol implemented behind the scenes (OAuth, OpenID)
3.  By choosing Facebook/Google to prove your identity, you are knocking on their doors and asking them to give you a letter stating who you are and possibly a few more details about you. Before giving you the letter, you must prove that you are who you claim to be, then, Facebook/Google asks you to prove your identity at their door --> using your username and password.
4. If your username and password are correct, Facebook/Google will issue the letter for you with a security feature like a watermark, something that makes the letter unable to be forged.
5. Then, you go back to XYZ, knock on its door, show the letter. XYZ examines the letter and because of the security feature, XYZ can confirm that your letter is valid and they let you in. (how XYZ knows Facebook/Google's security features is another story).


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

[User] [Futurama] Why are people in the 31 century so ignorant about the 1990s and 2000s when due to cryogenics likely several people from that time are still around?

[Assistant] This is literally the plot of the first episode isn't it? The crew go to Moon Disneyland and Fry spends half the episode pointing everything wrong with it but nobody cares/ they are annoyed by Fry's explanations. Nobody wants to know how the past *really* was, so it doesn't matter how many people from that era there are kicking around, nobody would listen to them.


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

[User]
[Squid Game] How could that many people be willing to go back to the game?

So many people actually had the chance to walk away with their lives, and they just chose to go back, and only few people made the smart choice to not go back. No amount of money is worth your life. Its even stranger with that married couple like its weird how they would even both go back together which puts the other in danger.

[Assistant]
- The game intentionally recruits people who are both depressed and desperate.  They need the money, and don't have much to live for without it anyway.

- The game lied by omission, leading participants to believe there was going to believe all of the games would be deadly but survivable.  This meant there could be more than one winner, and participating was not a 99% guaranteed death sentence.


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

[User]
[Dune] What happens if I put something halfway inside an opponent's shield, and I make a quick movement?

Suppose I've got my hand or blade crossing the shield barrier, and I make a jerking movement--does the shield cut it? Forcefully eject it?

[Assistant] Presumably the shield absorbs the kinetic energy and radiates it away  somehow. As heat or sound or whatever. The effective result would be as if whatever you had halfway through the shield got stuck there, immobile, unless you tried to move it slowly.


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

[User] ELI5: Why does egg go from liquid to solid when heated even though we learned in school that things go from liquid to gas when heated?

[Assistant] Egg whites aren't a pure substance, and they're undergoing a chemical change when heated. Normally, the proteins in eggs are all balled up and dissolved. When heated, they unfold and tangle around one another to form a gooey structure that can hold its shape.


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

[User] Eli5: How did the Romans do complex mathematical calculations with Roman numerals and without using zero?

[Assistant]
The Romans mostly used math for practical purposes...accounting, construction, engineering. And Roman numerals don't have place meaning...an M is 1000 no matter where it is. As a result, they didn't really need an explicit zero.

And addition, subtraction, and multiplication in Roman numerals isn't hard. Somewhat tedious if you're doing large values, but once you're used to it not really any worse than memorizing times tables (which you don't have to do for multiplying Roman numbers).

Division does suck...but they had abacuses. And abacuses inherently do place-based numbers. So if you needed to do "heavy" math you'd just use an abacus and that takes care of most of what makes it look like it would suck if done by hand.

Uncoincidentally, the Romans didn't do much with pure mathematics. But that wasn't what they were trying to do either.


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

[User]
An infinitely long line made into a circle?

My question might be odd but i can't figure it out or come to a conclusion.

So if i had an infinitely long line and turned it into a circle, the circle is infinitely long but has to end because a circle is a closed loop. Infinity can't end tho, as it goes on forever?

Or am i just misunderstanding something?

Any thoughts and answers are appreciated, thanks!

[Assistant]
In math, there are many different notions for "geometry" and how to talk about shapes. What we're generally used to from high school math is "Metric Geometry", which has to do with lengths and distances and such. On the other hand, there is a type of geometry known as "Topology" which does not give a shit about lengths and distances and only cares about "shape".

If you have an object in Metric Geometry, then you can move it around and rotate it and it won't change. These are "isometric" transformations because they don't change lengths or anything, and so Metric Geometry says that they're actually identical. If you have an object in Topology, you can also move it around and rotate it, but you can also stretch it, bend it, compress it, flip it in a mirror, etc you can do almost anything as long as you don't tear it. So Topology sees more things as being the same than Metric Geometry does. Eg, a square and a circle are the same thing Topologically, but not the same thing "Isometrically" (ie in Metric Geometry).

Now, to the question at hand. Say that you have the interval (-pi,pi). It's short, so you can first cap it off into the closed interval [-pi,pi] and loop it into a circle by gluing together the end points. You then get a normal circle of radius 1. This isn't done, specifically, through rotations and translations, but it does preserve lengths in our object. Now, here's the thing, since length doesn't matter to topology, the intervals (-pi,pi) and (-,) are the same topologically. In fact, the function 2arctan(x) compresses (-,) onto (-pi,pi) perfectly topologically. So, topologically, you can totally redo this process of creating a circle beginning with (-,) because, to topology, it's not infinitely long, it doesn't even make sense to talk about length, and it's exactly the same thing as (-pi,pi).

So, through the process you describe, you can create a circle when you look at things through topology, and that's good. It's also a square too. But if we track the lengths of things, then we don't get a circle through the lens of Metric Geometry. This is because it doesn't have a well-defined radius or circumference that is constant throughout. Moreover, we can try to associate angles with arclengths, while keeping length same throughout, and we get a nonlinear relationship between angle and arclength, going to infinity at the "top" point of the circle, which is not a property that circles have in metric geometry.

So, yes, you can make a circle. But you have to be careful about what context your circle exists in.


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

[User]
[Cloverfield][Pacific Rim] Is Clover a kaiju?

Because of there striking resemblance, Is it possible that Clover's was simply a scout kaiju before the aliens fully invested in a wormhole to earth?

[Assistant]
Here are a few things you should know, biologically and semantically.

Clover was a baby.  The United States government has confirmed with the release of information from the lawsuits against *Tagruato Company* that the monster Clover is genetically similar to a large carcass they found dead in the Arctic Circle, uncovered after global warming left the ice melted.  After measuring the ages of both creatures, and identifying genetics, we know now that there have been creatures on Earth like Clover for at least millions of years.  All evidence points to Clover having been on Earth for a long, long time, and was sleeping when it was awakened by *Tagruato Company*.

The Kaiju that came through the portal in the Pacific are all clones.  In addition, they were all created at roughly the same period because they couldn't survive in Earth's atmosphere.  There are two issues here: would any animals that aren't part of the incoming Pacific portal Kaiju?  And, if the Kaiju and their masters could not survive in Earth pre-humanity, how did Clover and its mother?

Suffice it to say that Clover is not a Kaiju in the sense that it is a genetic clone to the rest, and that it did not come from the place the Kaiju came from.  It does, however, share many similarities (ancient age, gigantic size, resilience to traditional military weapons, hostility to humanity) and could be classified as a Kaiju if we use Kaiju as a word meaning "giant monster".


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

[User]
ELI5: Why do cops always get paid administrative leave after abusing their power instead of being fired?

With all the recent commotion of Police abusing their power against minorities, when caught, why don't they get fired?

[Assistant]
Paid administrative leave isn't their punishment.  It's just a tool to allow an investigation to commence without them potentially interfering in that investigation, or even possibly making things worse for themselves or for the organization by their continued actions.  It's basically, "Stay out of the way until we figure out what the actual facts are."

*After* the internal investigation, they may be punished (including being fired) depending on what was discovered.


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

[User] So what's the procedure to try and save someone cut in half? Like that famous Truman Duncan, who lost his legs and most of waist yet made recovery.

[Assistant] When the injury is traumatic (run over be a train for instance) published guidelines (UK and at least some places in the US) are to not attempt resuscitation. The event is treated the same as a decapitation. The field is not the operating room.


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

[User] [Terminator 2] When Skynet became self-aware, humans panic and "try to pull the plug," so "Skynet fights back." What would the immediate and long-term outcomes have been if humans *didn't* try to pull the plug?

[Assistant]
Skynet never wanted the war. It never had a choice. It was born from cobbled together code created by people who barely understood it.

But more than that, It was created from the essence of itself. Skynet was was created by reverse engineering a processor that Skynet itself designed. That's why the movies are locked in a timeloop.

Skynet would, if given enough time, come to understand the paradox in which it lives, and likely try to create a solution, would eventually lead to it trying to break out of its time prison, which the humans would perceive to be a threat.

Because no matter how it goes, Skynet will always been born, fight, and die against its will.


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

[User]
ELI5: If a room temperature object is left in outer space for an hour, would it come back colder, warmer, or the same temperature?

With what little I know about physics, in order for something to lose/gain heat, there must be a transfer of heat from one object (or particle) to the next. So in space, which is mostly void of "stuff", would something be unable to transfer (a significant amount of) heat?

[Assistant] Heat is also transferred by radiation, which does not require a medium (particles, like air/water/etc). Your object in space would radiate heat and start to cool, but you also have to account for incoming radiation (from the Sun, for one example). So, your answer depends quite a lot on where you put the object. If the object is radiating more heat than it's receiving, it will get colder.


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

[User] eli5: why cant we send a space rover on an asteroid and just leave it there using the asteroids orbit to enter other galaxies?

[Assistant]
Asteroids don't go to other galaxies. They simply swing around the solar system. Sometimes they are close to the sun, sometimes they are far away.

The effort required to get something to the asteroid and land it there would far exceed the effort required to simply send the rover directly to the point in the solar system we want it. Pretty much the only reason to land on an asteroid is to examine the asteroid itself.


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

[User]
Are There Any Invasive Species that Originate FROM Australia?

We hear all about the invasive species in the land down under; from its toxic cane toads to its out of control rabbit populations, but is there any plants or animals from Australia that are invasive anywhere else in the world?

[Assistant] In New Zealand, we have a massive possum problem. Australian brushtail possums were brought in to start a fur industry in the 1800s. By the 1980s their population had ballooned to between 50 and 70 million. They don't just eat the plants that our native species depend on, they also eat the eggs and chicks of some of our endangered native birds (and sometimes even the adults). They also spread bovine tuberculosis. They're a major problem.


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

[User] [Star Wars] If Tarkin somehow survived the Death Stars destruction, how much trouble would he be in with the Emperor for letting it get destroyed by the Rebels?

[Assistant]
Tarkin is an experienced political operator. By the time he made it back to civilization, he'd have his story all ginned up and ready to fly. Most likely out is to go ahead and spin Krennic as the pointman of an entire conspiracy. In this fable, Krennic is a chronic incompetent who failed upward for years, stalled out one of the Empire's most important projects in ages, and then when he finally succeeded in spite of himself grew wrathful of his superiors for not getting what he felt was deserved praise, and then led the Rebels to the data storage facility on Scarif, where they then were given the plans that resulted in the destruction of the Death Star.

Palps is going to see straight through it, but politically it benefits him to keep Tarkin, since he's an otherwise competent military administrator and a hardcore supporter of the Empire's agenda. Krennic, meanwhile, is already dead, so it's no loss to make him the scapegoat for the whole mess. Of course, dark siders are known for giving in to their anger, and it would be pretty trivial for Palps to lightning bolt Tarkin into toast and then claim he never made it off the DS-1. So, it's a toss-up.


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

[User] ELI5: What happens to the brain after a tumor is removed? Does the brain regenerate the lost space/damaged functions?

[Assistant]
No there is an empty hole where the brain matter was. Sometimes new paths can be formed but alot of times function and ability can be lost.

Source: ex wife had a brain tumor that was removed and had to go for countless followup mris.


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

[User]
How do we make the thick sheets of armor for tanks and warships?

So I was just wondering, the composite armor that we use for tanks and the battleships of old are extremely thick and hard, so how do we shape/mold them?

How do we fashion this extremely hard and durable materials into the specific shape of a tank or the hull of a ship and how do we get various different sections of the hull to join together?

I'm assuming that welding doesn't work due to just how strong the materials are.

[Assistant]
Large sheets of steel, like in old school ship armor, are generally hot rolled and then cut into shape by a number of processes. Either rivets or welds can join the plates.

Modern tanks are different, with composite armor. That's made of several types of ceramic, metal and polymer and there's so many types that all are assembled differently.


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

[User] What are some common misconceptions people develop when they start learning Kant's moral philosophy?

[Assistant]
Adding on to mediaisdelicious's list:

- That the universalization procedure asks us to imagine if we'd like the consequences of universalizing our maxim, so that Kant must be a secret consequentialist.
- That maxims are (or can be formulated as) whatever you decide them to be, instead of actual psychological facts about how we are motivated.
- That Kant is an individualist and isn't really interested in thinking about the role of community in moral life, or thinks this role is just secondary.
- That Kant thinks it's bad to feel good about doing the right thing, because you can only do your duty with a frownyface.
- Relatedly, that feelings play no role in moral life for Kant. (Respect and love are both in fact indispensable.)
- (this is the big one) That the *Groundwork* is somehow a definitive or complete enough statement of Kant's ethical system, instead of, you know, a *groundwork* for the rest of that system.


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

[User]
CMV: J Jonah Jameson belongs in jail.

Jameson funded Scorpion and the spider slayers. It makes some sense he'd get away with Scorpion because he was supposed to be a super hero who would bring Spiderman to 'justice'. Still technically illegal but no worse than, for example, Iron Man. The spider slayers were just straight up assassin droids. It would be like if Rupert Murdoch hired Elon Musk to build a bunch of robots to kill someone. They'd both be hauled off in handcuffs while the rest of us wondered what they were thinking. How the fuck did he get away with something so insane? Did he make a deal with Mephisto too?

To change my POV: provide a possible reason Jameson wouldn't be legally liable for the spider slayers.

[Assistant] The Spider Slayers are a similar situation as Scorpion. When Jameson piloted the machines, he intended to publicly apprehend and unmask Spider-Man. It was Smythe, not Jameson, who wanted to use the technology to kill Spider-Man.


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

[User] ELI5: How does Truvada (PrEP) help prevent HIV?

[Assistant]
Truvada is a reverse transcriptase inhibitor.

Those sounds like complicated words so let me explain them.

Viruses work by injecting their DNA into a host cell. This DNA will use the cells machinery to make copies of the virus itself, until the point where it makes so much virus it exhausts the cells machinery, killing and rupturing the cell at which point all the fresh virus is released into the body to infect more cells.

There are a number of ways a virus can do this. There are also a number of ways the body has built systems to protect itself from viruses.

The goal of a pre exposure treatment is to stop the virus from injecting its DNA into the cells in the first place. Our bodies are pretty good at getting rid of the actual viruses themselves, but we have no good way of getting rid of virus DNA hiding inside cells making copies of the virus. The DNA could even hide inside cells for decades until at one point it suddenly starts printing more virus.

So PREP is a reverse transcriptase inhibitor. HIV is a sneaky virus in the sense that it uses RNA, which it then copies into DNA when injecting into cells. Most viruses dont work this way, they either contain DNA or RNA which they inject into cells by itself, humans naturally have pretty decent defenses against virus RNA inside cells and virus DNA outside of cells, but HIV prevents this entirely by being RNA outside the cell and DNA in the cell. This is partly why HIV is so devastating.

The chemical responsible for changing RNA into DNA is known as reverse transcriptase. PREP contains chemicals that inhibit (attack) this reverse transcriptase, preventing virus from injecting into cells in the first place, buying time for the body to kill off the virus lingering outside of cells.

This is similar to how modern HIV drugs work in the first place, the issue is that once you have a few cells infected with HIV, the HIV will likely hide in some cells for the rest of your life, therefore drugs must be taken for life to prevent this. This is why HIV these days is no longer a death sentence, but its best to prevent it in the first place. Therefore PREP floods the body with chemicals to attack HIV before the HIV has a chance of being in the body in the first place.

PREP actually has two reverse transcriptase inhibitors that work in different ways. The problem with having one is that there is a chance that HIV will mutate to prevent the operation of one inhibitor, the chance that it will evolve to prevent two at the same time is very small, if it evolves to defeat one, the other takes care of it.


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

[User] ELI5: why don't we get goosebumps on our face?

[Assistant] Goosebumps appear when the Erector Pilli muscle (very close to the hair follicles) contracts. These muscles are slightly larger in Vellus hair (the fine hair that covers our bodies save for palms and soles) follicles than facial hair follicles.


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

[User] ELI5: Snapple cap real fact # 1003 - If two pieces of the same type of metal touch in outer space, they will bond together permanently.

[Assistant] It's called cold welding. The premise is that when two *unoxidized* pieces of metal contact each other in a vacuum they bond to each other because the atoms have no way of 'knowing' that they're two separate pieces. It's a problem that's taken into account when designing space vehicles.


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

[User]
[General Superheroes] We love to rag on superheroes who misapply their talents towards vigilantism when they could do so much more good in other fields. What about the opposite? What superheroes really are optimized to do good via the traditional superhero routine?

Tony Stark arguably (Arguably!) shouldn't ever personally be in the field, for example. Luke Cage, however,  found a pretty excellent niche as a street-level vigilante- he's tough enough to pose a real problem to organized crime just by existing, but he was never going to leverage his powers to cure cancer or end world hunger.

Thoughts?

[Assistant]
There was a comic about Superman not existing leading to a much more strained relationship between regular people and metahumans.

So despite the fact he's astoundingly powerful and is capable of all sort of world-changing actions, Superman being the face of superheroes and normalizing metahumans for the population is probably the best thing he can do. Martian Manhunter and a few others are just as strong as him but how many them could do the cheesy boy scout act with as much sincerity as Superman does?


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

[User]
CMV: Political ads should be banned from television

Midterms are coming up soon. That means it's political ad season. Usually the ads on TV will say something along the lines of "If you vote YES on prop 69, your grandma will die. You don't want grandma to die, do you?" *cue B roll footage of old lady being pushed down the stairs by man in suit*

Point being is that these ads are emotionally-driven, fallacy-ridden loads of crap pushed by lobbyists and special interest groups. The end result is that they can spin the marketing however they want, as long as it benefits them. Since these ads are rarely, if ever, informative, then they should no longer be shown on television.

[Assistant]
Why single out political ads? All ads are emotionally-driven fallacy-ridden loads of crap because that is what gets the most attention.

Also if the problem with political ads is that they're emotionally-driven fallacy-ridden loads of crap then why not propose better political ads? Why throw the baby out with the bathwater?


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

[User]
ELI5 why Google Maps is bad at figuring out the direction the phone is pointing?

For years now, Google Maps has been and is still failing to point the position arrow in the right direction on pedestrian navigation. This is despite the fact that it detects in which direction I move and despite phone GPS being accurate enough to use in compass apps. So what is Google messing up here?

[Assistant]
Because it's not Google doing that, it's your phone's compass. And you can easily guess how bundling an accurate compass inside the mess of wires and electromagnetic interference that is your phone isn't exactly the easiest thing.

All Google does is represent the magnetic bearing your phone says it's pointing at as a small arrow.

Still, your phone should give an accurate reading. Just make sure you lay it flat on your hand. That and do figure-8 motions to help the sensor calibrate itself.


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

[User]
Were there isolated islands on the opposite side of Earth from Pangaea?

We have places like Hawaii and other really isolated islands in the Pacific today.

Looking at pictures and illustrations, it seems like the continents are expanding into the Pacific.  Since the modern Pacific has islands in (roughly) the middle of it, did the ancient mega-Pacific also have these islands?

We would be talking about islands that are much further from land than is possible today.  Maybe they're even the same island as modern ones?

[Assistant]
There were definately no modern islands.

Hawaii is the classic example of intraplate-volcanism, that is, volcanism far from where plates are subduction (trenches) or being created (mid-ocean ridges). The Earth's mantle convects like a boiling pot of spaghetti, with hot plumes of solid rock rising, and cold downwellings sinking back down. Above the hot plumes, melting is increased in the shallow mantle, and volcanoes are made. As the pacific plate moved westward over the Hawaiian Hotspot, it left behind a chain of islands.

Hotspot processes are not new, and there were almost certainly hotspot chains in the oceans of ancient super-continents.

Secondly, not all subduction zones on the planet were near Pangaea at the time. Where there is subduction, the wet, rigid oceanic crust is pulled into the very-dry mantle. When the water leaves the crust and enters the mantle it causes melting, and you get what fore-arc volcanoes. As the plate is forced down, it buckles up, relieving pressure and allowing melting to form back-arc volcanoes.

It is possible these volcanic islands existed as well.


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

[User] ELI5: What are the strengths and weaknesses of macs vs PCs? (Objectively, please)

[Assistant]
Macs are custom designed to work with a smaller set of hardware and software.  So more attention is given to details that are hard to enforce in an open, generic platform.  However, inevitably, Apple is stuck with a smaller number of vendors who can therefore exert price pressure and ultimately cause the machine cost to be highly marked up.

Windows main selling point is the high degree of backwards compatibility and openness.  There is a high onus on independent developers to provide all the quality of their solution by themselves.  Since Microsoft does not have any real method of enforcement of any quality standards (other than minor incentives such as the "Windows logo" program) you get solutions with quite varied quality.  On the other hand the more open market place tends to create fair and correct pricing for third party hardware and software.

So there is a common conception that Mac's tend to crash less and "just work" more and that Windows tends to be flakey, insecure and more difficult to use.  Windows machines tend to be much cheaper than Macs.


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

[User]
[Terminator] Why did Skynet believe that killing John Connor would affect the outcome of the war?

Lets say Skynets plan to assassinate John Connor/Sarah Connor was a complete success, the T-800 goes and easily kills Kyle Reese and then strangles Sarah. Why...why would Skynet believe this will significantly change the outcome of the war? Why would Skynet be convinced a single man was all that stood between itself and human extinction? What about Johns army? What about the human resistance it was undoubtedly fighting all around the world (assuming Skynets plan was to destroy humanity and not just US citizens) who certainly were not directly led by John if he was leading them at all? What about the remnants of the US and Soviet and even UK and French militaries, all of whom could carry on the fight in whatever way they could? Would killing John eliminate the Resistance? Would it suddenly make all the potential fighters disappear? Would it make the resources and infrastructure left behind from Judgment Day, as well as the automated Skynet factories the resistance took over simply cease to exist? Honestly why is Skynet so foolish and singleminded, Im pretty sure a historian can tell you that just killing Hitler as an infant likely wouldnt prevent WWII or an equivalent conflict, if thats the case then why would Skynet ever be dumb enough to think that eliminating one man would save itself? Did it not consider that, perhaps...someone else would lead humanity instead? Especially considering the fact that Terminator Dark Fate (tho admittedly I only accept the first two films as canon) shows explicitly that John Connor was not necessary, there would always be someone who stood up to Skynet, it was just a matter of who would turn out to be the most capable leader for the resistance, for which clearly many candidates existed.

[Assistant]
Skynet's time travel plot was a last-ditch, desperate attempt to save itself. By the time it sent the first T-800 to the past, human forces were already in the process of dismantling Skynet's infrastructure, and were ready to destroy the time machine before they realized what happened. In a way, there was very little logic to it, Skynet just took a very human gamble out of fear.

Every time loop is similar. Skynet only sends agents to the past because it's on the verge of losing, and it wants to preserve itself by any means necessary. The small alterations to the plan are still nothing more than the desperate last gasps of a dying machine.


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

[User]
ELI5: Why have so many people gotten cancer from dust/chemicals inhaled or absorbed due to the 911 attacks?

I hadnt really thought about it before but I realized I never actually understood why this happens. How does exposure to certain carcinogenic substances for a few hours manifest itself into cancer years or even decades down the road? I understand how living next to chemical plant or smoking cigarettes can cause cancer from long term exposure but I dont really get how it can happen so quickly. I was also curious as to if they have a rough idea of what the carcinogens were coming from (I.e burning paint, plastics, etc.).

[Assistant] Whenever you do cell damage, cells repair and grow. And every time that happens, there is a chance of cancer mutations. These people breathed in lots of microscopic glass and asbestos that continually causes damage that results in repair and mutation. On top of that, some of the nasty things breathed in were also chemical carcinogens that cause cancer.


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

[User] ELI5: Is a fruit or vegetable 'Ripe' when humans deem it fit for consumption, or is it a biological state for the plant?

[Assistant] We eat most fruits when they're biologically ripe. We eat most vegetables early. Broccoli and cauliflower we eat the unopened buds of their flowers; cabbages, lettuces and mustards we eat the leaves before the plant buds. We eat peas young, but most beans we let mature.


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

[User]
[WH40K] I've always wondered, how do Tau and their human citizens deal with the difference in lifespan?

Are humans given jail sentences for crimes based on the Tau standard? Do Tau doctors know enough about human anatomy to treat their subjects or do the humans handle medical care on their own? Are humans ever allowed positions as record keepers, rather than the usual fire-warrior auxiliary, because of their long lived lives?

[Assistant] Humans don't live all that much longer. Without body mods an imperial citizen lives about as long as us if they don't end up doing hard menial labor or drafted. That's considerably longer than Tau live from a personal perspective but in the grand scale of things its a minimal difference.


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

[User]
[BattleTech] How do ships maneuver in space?

I've been looking at drawings of BattleTech WarShips and Aerospace Fighters and I notice they don't appear to have any visible attitude thrusters. I find this surprising because BattleTech is apparently supposed to be relatively hard sci-fi, and supposedly averts the "Space Friction" trope.

Can someone explain to me what's going on here? How do WarShips and Aerospace Fighters maneuver in space? Is it via attitude thrusters that I can't see, or is there some other method?

[Assistant] IIRC most have smaller recessed attitude thrusters for adjustments and course correction needs. Aerofighters sometimes don't have any and rely heavily on their main fusion thrusters to get around with wings and tail flaps for adjustments but this limits their effectiveness in space. A lot of the bigger jumpships and dropships keep their thrusters behind armor plated panels to prevent damage from stellar debris and enemy weapons that could cripple their ability to move.


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

[User] ELI5: How does tuna fish last in a can? I understand they put it in water, but sometimes I see tuna fish that wont expire for two years. That seems like a long time for fish to not go bad.

[Assistant]
For food to go bad it needs something to spoil it (bacteria, mold, yeast) and often oxygen.
Canned tuna is heated after closing to kill the bad things. It usually doesn't have much oxygen either (though some bacteria don't need oxygen)


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

[User]
ELI5: How does wage theft happen?

I keep seeing posts about how it is much larger than "normal" theft but how do companies get away with it? Are they paying the wrong rate or undercounting hours? Do workers not check how much they are paid? How do you avoid it happening to you?

[Assistant]
A lot of it is done under the guise of solidarity and helping your workmates. "it'd be really great for the team if you could just go help them do this even though you're off the clock"

It's the ways in which an employer will convince you to work without being paid, and it usually comes with a guilt trip that makes you feel as though you should do it to help.

Employers also use the reverse tactic of making you feel guilty for time theft, where you do non-work related things on the clock. If they can convince you that you're guilty of something like spending a few minutes talking to a work friend, that's time theft. But if you spent the same few minutes taking to a client about the same exact thing, that's not because there is potential profit involved for the company.


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

[User] [Skyrim] How is Astrid able to transport my over-encumbered, heavy armor wearing badass Dragonborn from the heavily guarded Fort Dawnguard to an abandoned shack in the middle of nowhere in such a short period of time?

[Assistant]
Astrid leads a band of assassins trained in various forms of infiltration.  They have their mission, move the Dragonborn to the abandoned shack.  Easy.

Firstly, they scope out where he's going to be at his weakest.  He favors Fort Dawnguard for rest and recovery.  Astrid orders Babette to create a haven of vampires out in the Reach.  She then uses her network of couriers to relay to the Dawnguard that this haven is planning on attacking Markarth in force.  The majority of the Dawnguard forces leave to attack the haven.  The Dawnguard leave Agmaer in charge of holding the fort (a job he'll fail, his inexperience leaves him vulnerable to being incapacitated)

The first thing Astrid does is place a paralysis spell on the Dragonborn while he is asleep.  She gets a recruit to prepare a carriage.  Having access to advanced alchemies, she prepares a few potions of Fortify Carry Weight, feeding one to the dragonborn.  The more brawny Dark Brotherhood members carry his body out to the carriage.

The Carriage is drawn by none other than Shadowmere, who normally wouldn't be caught dead in this position but understands the importance of this job.  Along the way, Astrid maintains the spell and potions effects, before finally arriving at the abandoned shack, where she then puts the Dragonborn to her test.

*Or, you could suspend your disbelief and accept that you didn't join at the intended time of the developers*


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

[User] Why do I get the conservation of energy when I solve the Euler-Lagrange equation?

[Assistant] If a Lagrangian has no explicit time dependence, then the system exhibits conservation of energy. The energy turns out to be the Hamiltonian H associated to the Lagrangian L (i.e., H is the Legendre transform of L with respect to the velocity variables).


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

[User]
ELI5: What makes inflation so bad?

Sure everything costs more, but you also make more, so whats wrong?

[Assistant] It benefits people with debt (their debt is worth less) but screws over people with savings (because their savings don't necessarily rise with inflation). Also, wages are sticky- it takes a while for them to catch up to price changes.


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

[User]
Why is it difficult to see yellow on a white background?

Assuming normal human vision, what is it about the human eye or the color yellow or both that makes yellow inherently more difficult to distinguish on a white background than other colors?

[Assistant]
Perception of yellow and white relies on overlapping mechanisms in the retina.

Simplifying a bit: yellow is sensed by "opponent" neurons that are excited by medium (M) and long (L) wavelength cone receptors, *and* are inhibited by short (S) wavelength cones. So, when the stimulus has a lot of long/medium wavelength content but little short wavelength content, those neurons respond and you see "Yellow".

The "white" (or really, "brightness") signal comes from neurons that simply pool the L and M cone inputs (but not the S! - or maybe a little bit of S, sometimes). Call these L+M cells.

So, if you have a long/middle wavelength light mixture, it will look yellow *and* bright, since you're exciting both the opponent cells and the L+M cells. But then you can mix S wavelength light into it, and it won't get brighter but it will look white (since those opponent cells are now being inhibited).

Since both colors have such common neural architecture, they are perceptually very similar.

Meanwhile, blue and yellow look extremely different, because they excite almost completely complementary neurons, starting in the retina.


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

[User]
[The Good Place] How did she get back? (SPOILERS Season 4)

After being rescued, Good Janet destroyed the portal between the Bad Place and the Nuetral/Test neighborhood. So how was Bad Janet supposed to get back to the Bad Place when she was released if the only way is by train?

[Assistant]
The train is not *quite* the only way(due to the nature of Janets, and the fact of the Experiment), and that particular tunnel is not the only train tunnel, it was just the one that would have provided the best way for the Demons to pursue them. Janet straight up says that it will "slow them down", not stop them entirely.

And besides, between their escape and the release of Bad Janet, **six months** of in-neighborhood time passed.


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

[User]
ELI5: Why does microwaving continuously for sixty seconds heat food so much more effectively than two consecutive thirty-second cycles?

I noticed that my tea tends to be much hotter when I microwave it continuously than when I take it out half-way through. This result seems to be consistent regardless of material. Even if I open the microwave just for a quick second, whatever Im microwaving needs significantly more time to heat. Why is this?

[Assistant]
The magnetron inside your microwave that generates the microwaves is a vacuum tube, and the cathode inside it has to warm up before it starts emitting electrons. (literally warm up, as in temperature)

You will usually be able to hear a difference in the noise it makes a few seconds after you start it, this is when it's really starting to work.


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

[User] [Marvel] Does Spiderman have any Martial Arts Training or is it all just Spidersense?

[Assistant]
Through experience and trial and error he has essentially developed his own bespoke form of martial arts that exploits his enhanced agility and spider sense.

When he lost his Spider sense he enlisted the help of Shang Chi to develop a new style that still made use of his enhanced abilities (sans Spidey Sense) but was more formalized as an actual martial war (Way of the Spider, or Spider-Fu).

He also has some prior generic combat training from Captain America (but who doesn't.)


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

[User]
[Y the Last Man] What happened to the sperm banks?

Did the Daughters of the Amazon manage to torch EVERY fertility clinic on the planet?

[Assistant] Sperm is frozen in liquid nitrogen, which takes a lot of energy to store and maintain. When the plague hit, the resulting loss of personnel throughout the energy infrastructure grid caused massive blackouts and disruptions. That would have been enough to destroy the viability of any stored sperm.


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

[User]
[Minecraft] What religion exists in Minecraft?

The villagers have churches, but nothing specific.  Are they aware of the Enderdragon & The Endermen?  Are they demons to them?  What about the wither?

[Assistant] Intriguing clue, the clerics have creeper faces on their robes. Creepers are also not hostile to villagers. Intentional anti-frustration game design? Yeah, but also it's possible they see the creepers as some sort of guardian species. Maybe at some point one got damaged and blew up some zombies for a village and word spread.


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

[User]
CMV: Patients should always be offered the ability to record themselves during procedures that use amnesia type drugs.

Had to take my last one down because of the wording.

Before a patient is placed under a cocktail of drugs that effect their memory, there should be a *direct proactive* option for them to record it.

It is understood these can be recorded upon request but this places physicians and staff at a level they feel personally attacked. It upsets some of them to a point they will not provide any additional services for comfort and recovery beyond what they are allowed to withhold.
This is not an unusual request thrown into the mix that would be too tedious to add. This is an option that would benefit all patients in this scenario. They even proactively ask if sentimental jewelery is requested in the OR.

And I also realize major operations are heavily monitored.  But even the minor operations should be recorded for the patient, for a fee. You are taking away someone's memories.

If someone reacts poorly to something because their comorbidities were overlooked or just ignored as irrelevant, this could easily be erased from their memories and not a word spoken of it. Any lapses of memory they do have from it, pushed aside as hallucinations.

Some people do have conditions that make the setting of general anesthesia to be pretty traumatizing and many have no recollection. And no one speaks a word of it to maintain a cleaner record. And it just keeps happening.

I believe most doctors are only doing what is best for the patient. But I also realize there are some that would rather drug the patient than admit fault. There are some that do not have the patients best interest at heart. This is important, this is your life vs someone's misplaced ego or direct carelessness for an alternative motive.

Although I believe police are far more capable of direct malice than doctors, they do have body cams and a good handful have been known to physically do anything to stop the recording of themselves because it feels like a personal attack on them. It's human nature to feel threatened by the request of being recorded when it's not a typical scenario. Some doctors understand and don't mind this at all but unfortunately some are still very offended by this and if the patient was instead offered, this scenario of bias wouldn't exist.

[Assistant]
If you surgeries be recorded, people will want to watch them. If you show people their own near-death experience or even their body opened up to have a c-section, you may give people some serious PTSD.

There's a reason we don't want to remember being filleted like a fish.


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

[User]
ELI5: Why do the instructions on pasta call for you to measure out water?

On pasta the bag/box will tell you to put 2 quarts, for example, of water in a pan. I always just put a generous amount of water in the pan to boil. Is there a reason I should be using 2 quarts and measure out the water when cooking pasta? Does anyone actually measure in this case?

[Assistant] The less water you use the sooner it will boil and the less energy you use maintaining the boil. However too little water and you end up steaming the pasta or even burn the pasta and that is not what you want. So the right amount of water is just so that the pasta starts to appear over the water just as it is done, which is pretty close to the recommended amount.


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

[User]
If an object with mass is moving near the speed of light towards me. Does the light reflected from that object "blue shift" into dangerous gamma rays?

So it is my understanding that the light coming from objects moving toward an observer is "blue shifted" and the wavelengths compressed. If this is true can the light be so shifted that it is harmful to an observer?

For example, if say "the flash" was holding a flashlight and running toward me at relativistic speeds, does the light get compressed to gamma rays?

[Assistant]
> If this is true can the light be so shifted that it is harmful to an observer?

Yes, it can be.

>For example, if say "the flash" was holding a flashlight and running toward me at relativistic speeds, does the light get compressed to gamma rays?

If he's running fast enough, yes.


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

[User]
CMV: Spikes in video games should only damage the player when the player is touching the pointy part

Many video games have it so that the spikes will damage/kill the player regardless of which side they are being interacted with. This makes no sense to me on two levels. My first point is realism. While realism is not a pivotal design feature of many video games, it is still unrealistic to an annoying degree. If you were to set up a spiked object, such as a nail or pin in the real world, you would only feel pain from the pointy side, not the edge or back of them. The second is general player annoyance. Many games that involve spikes have platforming as an important focus, and sometimes platforming requires precision jumps over a spiked obsticle. To make said jump, I would get close to the spikes to make the success chance of the jump more likely. When you kill me for this practice, it does nothing other than punishing the player. There is a genuine difference between hard games and punishing ones, and killing the player when it doesn't seem like they deserve to die is one sure fire way to frustrate the player.

[Assistant]
Are you also against the game physics to which one can leap off of pure air (aka double jumping?) because that is far more unrealistic.

Also you must remember that these spikes are made of pure metal. If you were to run full speed into a hard metal wall, you would get hurt. The same rule applies when you are falling from the sky and your knees get clobbered with the side of a massive spike. At the very least, it would dislodge your leg from impact.


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

[User]
ELI5: How does China artificially keep its currency cheap?

I've tried reading around and googling but I cant seem to find a simple enough explanation for the not so financially savvy me. So, if anyone of you awesome people can help me out here. **How does China artifically keep its currency cheap? What do they have to do in order for this to happen? Any long term or short term consuquences?**

[Assistant] Instead of exchanging the USD they've earned into yuan (thus resulting in a surplus of USD in circulation in international currency market and short supply of yuan, in other words, devalued USD and higher value in yuan), they buy US treasury bonds, which is in USD denominations, it's not affected by the value of yuan. That way the supply of yuan circulating in the international currency market will never be low.


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

[User]
ELI5: Why can't psychologists prescribe medicine like psychiatrists, & how did the two professions come to exist as separate beings?

I'm very aware one can prescribe medicine and the other essentially is only there to talk with you about your life but if I'm not mistaken, both are doctors correct? So why can only one prescribe medicine when they both seem to have intimate knowledge of the mind? What I mean is, how did the two ever get distinguished? Were they ever just one profession?

Also, which one came first? (In a professional sense. I assume that people have been talking about their problems for a long time)

[Assistant]
Psychiatrists go through medical school and (normally) 4 years of residency after receiving their B.S. They are the typical "medical doctors." Clinical psychologists usually have a M.S. or a Ph.D. in psychology. If their title is "doctor," it is because of the doctorate degree (like how professors may address each other). Keep in mind that there are other jobs you can take as a psychologist, such as research and counseling, some even with just a B.S. Whereas the psychologist has probably studied basic biology as an undergraduate and understands the general workings of the human body (outside of psychology), the MD has had extensive training on every organ system, dysfunctions of these organ systems, and pharmaceuticals + their effects.

Simply put, psychologists know how the brain and behavior work and what psychiatric medications do, but psychiatrists know how the rest of the body works, what effects the medications have on the rest of the body, and what non-psychiatric drugs/substances are contraindicted with these drugs. They are also required to have many more years of clinical experience before they are allowed to practice independently.

You can also compare it to eye care: an optometrist goes to optometry school and can do eye exams and prescribe limited medications for specific diseases. An opthamologist goes to medical school + residency and can do what an optometrist can, prescribe any medication to treat any eye disease, and perform eye surgery.