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

[User]
ELI5: why was a seemingly random set of notes chosen as the "standard" tuning for a guitar? When and how was this tuning decided upon?

I know a little bit about musical theory and have been playing guitar for most of my life, albeit casually, yet this question only occurred to me recently.

[Assistant]
The guitar is a latecomer in a long line of string instruments that are tuned "4-3-4" (after the intervals separating the strings).  There's a lot of ancient 4-string instruments tuned so that the interval between the two middle strings is a major third, and the interval between an outer string and its adjacent string is a major fourth.  The ukulele is tuned like this, for example.  And the guitar is basically like a larger, six-string ukulele with two extra bass strings tuned in fourths.

But still, why?  Well, first, let's consider the alternatives:

* **Open tuning:** the guitar is tuned so that when all the strings are played open together, some specific chord is played out.  This is a traditional alternative tuning as well, used often in blues.  Some instruments like pedal steel guitar are also normally tuned like this.
* **Fourths tuning:** all strings are tuned in fourths.  Not nearly as common, but a few musicians use it.

Open tuning makes it really easy to play chords for a chosen key using all strings (which gives a fuller sound), but playing scales and transposing become more difficult.  Fourths tuning makes it easy to play scales and transpose, but chords are much more limited (you're basically stuck with four strings at a time).

The standard tuning offers a balance between those two alternatives.  There's a bunch of easy open chord shapes for more than one key.  You also get easy five-or-six string barre chords all over the neck for any key.  Scales are somewhat harder than fourths tuning, but not nearly as hard as in open tuning.


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

[User]
[General] What's the most horrible prison in all of fiction?

Like Impel Down is pretty bad with its five floors of hell and Chronicles of Riddick has a pretty bad prison system.

But what's the worst in fiction?

[Assistant]
Azkaban has to get a mention.

Its a dark, cold, wet, basically inescapable place, guarded by horrifying, soul-sucking demons that make feeling happiness literally impossible. Hope, joy, etc... all of those emotions simply cannot be felt once Dementors get a hold of you.

Stay exposed long enough and apparently Dementors can also make it harder/borderline impossible to remember happy memories.

The prisoners of Azkaban are essentially robbed of all happiness, hope and positive experience. It's a prison explicitly designed to inflict depression (which makes some sense in universe - depression is one of the few ways to significantly dampen a wizard's powers), and forces its inhabitants to stew in a cesspool of their own worst memories.


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

[User]
[1984] Is it ever established who the supreme leader/head of the Inner Party is?

I just finished the book and the movie, and I don't believe it's ever established who the head of State is, beyond the symbolic Big Brother, who may or may not actually exist.

We know of two Inner Party members, O'Brien and the shop clerk. But we are never given a clue as to who actually controls the Party/State beyond the Big Brother image.

[Assistant]
There is no supreme leader. The inner party itself is the leader. It exists merely to perpetuate it's own power and status. Any attempts to coalesce behind an individual rather than the party itself is met with imprisonment or worse.

There's likely a figurehead that acts as a mouthpiece to the party but they are far removed from being anything more than a town crier for the whims of big brother.


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

[User]
ELI5:Why does ~x = -x - 1?

I've always been confused about why the bitwise negation `~` of any number `x` equals `-x - 1`.

Should the bitwise negation flip each bit from 1 to 0 and vice versa?

For example, `~10 = -11`, but the binary representation of `10` is `1010` and the binary representation of `-11` is `-1011`?

How come that works?

[Assistant]
In binary math, for most systems, we use what is called Two's complement. It is a way to eliminate the possibility of a positive and negative 0.

The highest bit (the left-most bit in a binary sequence) is the sign bit. If it is 1, it is a negative number. If it is 0, it is either 0 or a positive number.

If you were to flip 0, and we didn't do this, you'd end up with all 1s. Instead of having to check between 2 different versions of 0 (one 'negative' and one 'positive'), it is more efficient to just check against one version. This gives an extra integer to use and still works out to correct answers when using binary math (addition and subtraction) without requiring conversion.


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

[User]
ELI5: How do people plant trees in the millions on such short notice e.g. like on environmental events?

Surely they don't manually plant each seed one by one?

[Assistant]
In the forestry industry an experienced planter on fast ground (i.e. flat, soft soil, no logs/branches/brush in the way) can plant 3000+ trees per day. They nearly always get paid piece rate, hence theyre motivated to go quickly.

Its hard work.

I would think that for those enviro events they get huge numbers of people to plant a couple of hundred each.


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

[User]
[Jackie Chan Adventures] If Captain Black doesn't believe in magic, then why is he having Section 13 collect and guard the talismans? Aren't they just useless pieces of rock to him?

I'm just watching this old cartoon which I used to watch back in the 2000s - it is still great - and I don't get why Section 13 care about the talismans if they don't believe they grant magical powers.

[Assistant]
Love this show.

Illegal theft of priceless antiques is still a big deal.

As a matter of fact in the modern world we're increasingly seeing terror cells funding themselves on the black market antiquities trade.

He's been trying to take down the Dark Hand for a while so if the Dark Hand is going after antiquities that's where he'll look.


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

[User]
CMV: There should be more minority characters in movies/TV that are villains.

Whenever the topic of minority representation comes up, it primarily talks about protagonists or hero representation. That's all well and good, but eventually we'll have to talk about the flipside of the discussion.
Of course we have had great villains that were minorities (ex: Killmonger, dang what a great villain).
But at least from what I see, most villains (especially in action/superhero movies) either boil down to "calm and collected British bad guy" or "evil Eastern European guy."
It may be that studios are afraid to cast minority characters as villains. The key here is the two camps of minority villains.
One camp I call the "Killmonger camp", where the villains motivation is directly tied to their minority status, and that is purposely portrayed to be in at least a sympathetic light.
The other camp is the straight up villain, that just happens to be a minority. Take Dr. Wu from Jurassic World, or Black Mask from Birds of Prey. Black Mask is a brutal gang boss who enjoys cutting people's faces off, and also happens to be gay.
As the discussion of minority representation in movies increases, why not give Blacks, Asians, LGBT, people with disabilities fun and scene-chewing villainous roles?
This is isnt a big issue, but I feel like it's at least worth talking about.

[Assistant]
That is one of the basis of the theory of accurate minority representation. According to a 1969 article by Cedric Clark, there are four stages of representation:

-Non-recognition: the minority is not represented and do not appear significantly in the media. Transgenders are there, only a handful of shows have transgender characters.

-Ridicule: The minority is shown as a subject of mockery and only exists in comedy. Gay people are mostly there, but it's starting to evolve toward the next step,

-Regulation: The character is shown in socially acceptable, generally model or idealized roles. They almost never play villains. Here you can find women, black people.

-Respect: The minority is cast in all roles and as deeper character, on par with the majority characters, and can actually be good or bad. The characters are more real than just stock characters constantly used, and can be villains. Here you can find white "minorities," eastern europeans, Irish, Italians - mostly people that used to be minorities but are considered white now.

So the endgame is indeed more villains being from minorities, but some still have a long way to go before we reach that stage, and it's unclear what happens when we skip steps - a lot of people have been outraged by a transexual villain, recently.


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

[User]
[Elder Scrolls] So what's Oblivion like? Actual Oblivion as in the space between realms I mean.

Is it like 40K's Warp, or legit outer space?

[Assistant]
It is impossible for a mortal mind to comprehend.

You can actually see it, you know? look at the sky at a clear night, and you see "stars".
This isn't actually stars, but holes in our plane of oblivion. Yes, Nirn is a plane of oblivion like the others.
Significantly less on fire than most, though, i quite like it here.

The sun, like the stars, are also a hole in our plane of oblivion, made when the god of Magic, Magnus, left our plane of existence after making it.. It is much bigger, though, which explains why it hurts to look at it.

So, more like WH40k warp, but less crowded.


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

[User] [Daredevil Ben Affleck non-MCU 2003 Film] If Daredevil's only power is his enhanced senses, how is he able to regularly make multi-story jumps and falls without injury?

[Assistant]
Matt is also one of the greatest gymnasts to ever live. He has an innate athletic ability, just like his father had an innate ability as a boxer, and he has the willpower to maximize that through training.

Add to that the standard "humans in that universe are just better at shit than we are" and you've got a guy in a leather jumpsuit leaping over tall buildings in a single bound.


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

[User]
[Star Trek] Why is Genetic Engineering in humans frowned upon, but admitted for human-alien hybrids?

ber-humans like Khan cause a fit of outrage, but human-alien hybrids like Spock - people who need genetic engineering to be produced in a viable way - are seen as ok. Why is the Federation so selective on what is acceptable in terms of genetic modification?

[Assistant]
The Federation is fully accepting of vital life-saving genetic engineering, especially for unborn children who would have a hard time being born, or potentially live a challenging life. Some of the most common medical procedures in the Federation are screenings for genetic disorders, and then distributing gene-therapy cures to make sure they don't crop up later in life. Only the rarest and/or newest problems are incurable, and lead to heartache for everyone involved.

Hybrid children are very often in need of these vital procedures, and no planet in the Federation would ever stop parents from seeking out treatments to help their child grow up healthy.

The line is drawn where the engineering goes from *"helping an otherwise disadvantaged person live a healthy lifestyle"* to *"turning a healthy person into a superhuman"* (for lack of a better term) As we've seen time and again, superior ability breeds superior ambition, and basic human nature makes these people start viewing their peers as lessers, if not straight-up inhuman. (us-vs-them tribalism) And when an augmented being starts dehumanizing the "normals", they can do horrific things.

A few people, like Julian Bashir, can resist the temptation, but they're an extreme rarity. The chances of another Khan happening are too great when the idea of engineering becomes a pursuit of superpowers.


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

[User]
[Marvel Cinematic Universe] So, about the super soldier serum...

One of the coo things about Captain America is that he's utterly unique.  No one has since been able to recreate the super soldier serum since the 1940s.  Except....they have.

In The Incredible Hulk, they begin juicing Emil Blonsky with something that essentially makes him a super soldier.  He might not quite be on Cap's level at first, but when he first gets juiced, he is unquestionably a peak human.

For those saying he turned into The Abomination, that wasn't until *after* he went through a completely different test that he was warned *would turn him into a monster*.  If he, or anyone, simply went through 1 or 2 injections, they would simply remain peak human, with at worst the slightly scary spine thing Blonsky started developing.    And don't forget the serum was still *highly* experimental, so any kinks could still be worked out.

Point of all this being, have people just forgotten that a working super soldier serum exists?

[Assistant] The serum in Incredible Hulk, while seemingly similar to the Super Soldier Serum is not the same thing.  The "weird spine thing" was not the end all, and while he would not have become a full on Abomination, it probably would not have stopped there.  The serum also seriously messed with his judgement, which is more important.


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

[User] ELI5: Why can't a single blood test show you all the information you need instead of having to take multiple tests for different markers?

[Assistant]
A blood test looks at the number of molecules or ions in a specified volume of blood.

To get this information, you need to mix the blood with different chemicals to draw them out before processing them. This is why different blood bottles exist, because mixing with the wrong 'reagent' will produce errors.

Even the most basic (common, not necessarily easiest) blood test like kidney function is still looking for four things: urea, creatinine, sodium and potassium. They all get processed off the same bottle helpfully, but if you wanted to do a full blood count (haemoglobin, white cells etc etc) that's a different bottle and will give you upwards of 8 different numbers depending on the lab.

TL:DR - most blood tests are actually lots of results rolled into a list. There a far too many things in the blood to look for everything every time, it would cost tons.


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

[User]
[Vampires] Why is it necessary for a vampire to rest in their native soil to survive or travel?

-Why do they need the soil? Are they similar to plants?

-Why particularly that soil?

[Assistant]
A vampire's body is, as far as the normal and natural parts of the universe are concerned, dead. Right now, in the natural order of things, it ought to be resting in its native soil, dead and buried. But instead it's up and walking around. Sleeping in a coffin in soil is a vampire's way of creating a modest simulacrum of what ought to be, in order to prevent the forces of nature from more strongly rejecting its unnatural existence.

It's the same way an egg is incubated under a heat lamp if it can't be under its mother, or the way that we humans spread out to all biomes on Earth and obsessively try to make them look like golf courses (green grass, scattered trees, nice landmarks) which are a simulacrum of our natural habitat in the African savannah.


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

[User]
[Spider-Man] Why did Peter not sell his pictures to another newspaper?

Obviously JJJ had a vendetta against Spider-Man and wanted pictures to paint him as a menace, but wouldn't other media sources would pay more and be more appreciative of the work than our beloved Jolly Jonah?

[Assistant] To other newspapers, action shots of Spidey would get old news fast. Sure, he might make an inside page or something when a fight goes down and front page if there's something big. But by being billed as the city's biggest menace in the Bugle, he's always front page and that means steady money.


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

[User]
ELI5: Vitamins; what are they? How do they work? What processes in the body require them and how?

We're always being told certain things contain vitamins and that those are good for one's health, but what actually are they? What functions of the body require them, and how does it make use of them?

Bonus round: Antioxidants; another health food buzzword - what are they, and what do they do?

[Assistant]
A "vitamin," generally, is any of a group of groups of molecules, each group of molecules constituting one vitamin. For example, there are eight compounds that constitute vitamin E.

What constitutes a vitamin is that it can't be something the body makes on its own: we must take it in through our diet.

Here are the thirteen such groups that our bodies require, along with a non-exhaustive list of what our bodies need them for:

1. Vitamin A (used in eyesight, skin maintenance, human development)

2. The B complex (1, 2, 3, 5, 6, 7, 9, and 12) (used in cell metabolism)

3. Vitamin C (Used in immune response)

4. Vitamin D (controls absorption of calcium, magnesium, and phosphate in our gut)

5. Vitamin E (we're not sure quite what it does, but it may have antioxidant functions, while I'll get to)

6. Vitamin K (blood clotting, bone formation, etc)

Our bodies use these compounds in various ways: reaction mediation, breaking them down to use their components, etc.

#Bonus Question:

Antioxidants. As the name implies, they inhibit a class of reactions called "oxidation reactions," which is the same reaction that forms rust. In the body, instead of rust, they create something called a "free radical." A radical in general is anything with a single unpaired electron. Because of that, they are highly reactive. "Free" radicals are uncontrolled by the body, and they can inflict damage to us.


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

[User] Why do we strive for perfection if it is not attainable?

[Assistant] from a platonic perspective, humans can't ever truly achieve *any* abstract concept but merely shadow elements of it. of course, this doesn't mean that humans can't achieve a level of *ostensible* perfection, by mirroring enough palpable 'characteristics' of an abstract virtue in order to be perceived by peers as physically possessing it -- I'd argue that when individuals "strive for perfection" this deception of appearance, whether in themselves or their work, is moreso what they are striving for (which of course **is** attainable, and carries significant value in the eyes of society) rather than genuine metaphysical perfection in the purest sense.


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

[User]
[LOTR] What is the purpose of Sauron's tower/eye thing in Mordor?

He can only see a small area in his line of sight? What's the point of that? Is he trapped? Surely someone as powerful as he is can have physical form.

[Assistant]
In the books, the "Eye of Sauron" was a metaphor for Sauron's influence, not a literal eye. In the books Sauron had a body.

In the movies, they decided that the threat of the Ring was more real or easier to drive home if they suggested that Sauron can't "take physical form" without the Ring. (I believe they had Saruman say this.) It simplified the Ring's importance to the audience, and eliminates the inevitable questions that would arise from having your primary villain sit inside his tower for the entire trilogy. Making the eye a visual motif was something they determined to be more menacing than a dude in a tower, and more appropriate for the medium of film.

Having an unseen villain works better in a book than it does in an inherently visual medium, so one can see why they wanted to go in that direction to make him more compelling to audiences. But understand that "the Eye" was a solution to a practical problem in translating between mediums, and as such it shakes up the canon and creates questions like yours.

If we take the movies to be the canon in question and ignore the books: then the Eye is the spiritual manifestation of Sauron, kept alive presumably by the dark magic of the tower, until the Ring can be obtained to stabilize his existence permanently in this world.


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

[User] What would happen if a fully vaccinated individual were to contract coronavirus? Would it just feel like a light cold for them or would they literally not get sick at all?

[Assistant]
The purpose of a vaccine is to prepare the adaptive immune system for an invasion by a pathogen, so that when it arrives it is immediately recognized and destroyed. Symptoms are a result of tissue damage when pathogens destroy host cells far beyond initial invasion.

If you receive a low load long enough after you have been vaccinated you should experience nothing. A high load or frequent exposures will saturate your immunity and take effect to the extent that such a load would had you not been vaccinated.

If you are exposed within a short window after one of your vaccinations, your adaptive immune system will be saturated and you will likely be more sick than you would have been had you not gotten the jab.

Hope this clears things up.


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

[User]
Is everything natural?

I often hear people argue that some behaviour or social arrangement is natural as opposed to something that they wish to discredit. Obviously sometimes such claims are wrong because of other reasons, for example arguing that homosexual relationships  are unnatural is wrong from the biological perspective since we can observe them across numerous species etc.

My question is : would it be correct to argue that anything we do is natural because we evolved to have consciousness thus we can not claim that some actions/social practices are unnatural because they are the result of natural precesses such as evolution?

If "behaviour X in natural as opposed to behaviour Q" is a flawed argument, can we still use nature in our arguments without making a fallacious augment? If so could you please provide an example.

[Assistant]
Steve Vogel makes an argument similar to this in *Thinking Like a Mall* (2015). Richard Dawkins best book, *The Extended Phenotype* (1982), uses the concept of the phenotype to make a similar argument within the domain of biology.

Neither of these authors (IIRC) argue that there is *no distinction* between the natural and the artificial, only that the distinction needs to be drawn differently. Im sure there are authors who have made the former argument but none come immediately to mind.


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

[User]
[Star Trek] If Data were to marry would he be open to the idea of an open marriage?

Think about it. If you married an android and communicated to it exactly how you want to be fucked and since it has extreme stamina, strength, and dexterity it would probably be the fucking of a lifetime. But obviously since Data doesn't feel emotions it wouldn't necessarily be all that romantic and what not. A part of me says he would have no problem letting his wife get a little action on the side every now and again.

[Assistant]
Data in his emotionless mode, if for some reason chose marriage, would probably want to work out in exhausting detail what is expected of him and follow that to the letter.

The real question would be what his fiancee wants, as he would not likely have an opinion on the issue one way or another.


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

[User]
If I put two mirrors across from each other, then put an object for them to reflect and take it away, would the mirrors continue to reflect that object from each other? Why or why not? (Better explanation inside)

Okay so if I put a mirror on a wall facing away from the wall, and I put another mirror on the opposite wall (let's say 5 feet away) facing the away from its wall, and then put an object, let's say a baseball, in the middle of those two mirrors. Each mirror would reflect that baseball, right? And depending on what angle you look at the mirror from, you'd see a reflection of the thee mirror's reflection of the baseball. So if I took the baseball away, would each mirror keep reflecting the other mirror's reflection of the baseball?

[Assistant] As others have mentioned, even if you had two perfectly parallel mirrors and perfectly perpendicular light, the imperfect mirrors will absorb all the light pretty quickly, but here's another wrinkle: the beam of light would fall to the Earth at 9.8 m/s^2 due to gravity!


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

[User]
How likely is it that there is something fundamentally obvious about our surroundings that we havent picked up on yet?

Lets just say one day a caveman had 3 rocks in front of him but the idea of numbers hadnt quite clicked yet. On some level he is aware there are 3 rocks in front of him but he doesnt have a means like language to articulate the concept. The next day he has 5 rocks in front of him and he notices some are brown and some are grey. He separates the colours into 2 piles and notices that one pile is bigger than the other. The separation of the 2 colours is somewhat synonymous with counting here. Maybe some sort of revelation happens here where he notices that things that appear to be the same can be separated. Before he noticed colour, these rocks were all the same. But now they are different. Noticing that one pile is larger, he can now put value on the individual rock.

Im not sure if I lost my point somewhere in there, or if that is indeed how the caveman learnt to count. I was just thinking the idea of numbers seem fundamentaly obvious now and help greatly with our understanding of the universe. Is it possible that there is something similar that we just havent had that click moment yet?

[Assistant]
I think it is simple postulations like this that have led many philosphers of history to confess to epistemic ineptitude. Dan Dennett wrote a book, "Intuition Pumps (& other thinking tools) where Dennett describes how human technology and theory has evolved and aided in how we think and conceptualize our universe. A super basic example of this is the progression from language, to writing to mathematics. These are contemporary apparatuses of thinking that we all use somewhat inuitively everyday.

Often acquiring and refining these tools is the laborious chore of one exceptional fellow who visits us every few centuries. Surely some day in the future, we'll encounter some new theorical instruments that will trickle down to the common people and make our epoch of the mind seem foolish and hilariously incompetent.


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

[User]
ELI5: where do worms go in the winter?

I mean in cold weather climates where the ground freezes in the winter. Do worms just sorta freeze too and thaw in the spring? Do they all die and new ones hatch when the weather warms?

Edit: spelling, and yes I meant common earthworms. Thanks for the response!

[Assistant]
If you're referring to earthworms, they simply go deeper into the ground.  Even in harsh winters the ground doesn't usually freeze more than ~~an inch or two~~ a few feet deep, so the worms just burrow below the frozen layer and wait for a few weeks until it thaws out again.

*Edit* corrected how deep the ground freezes. TIL, etc ...


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

[User] At nighttime, how come i can see something better if i use my peripherals but if you stare directly at it the object gets darker and harder to see?

[Assistant]
Your eye has two different ways to "see" light - rods and cones. Rods are can see with less light, but don't see color. Cones can see color, but aren't very good in the dark.

The middle part of your eye has more cones than rods, and the outsides have more rods than cones. So you see better color in the middle, but better in the dark around the edges.


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

[User]
[KOTOR II] What was Kreias ultimate plan to destroy the Force?

And why did she need the Exile?

[Assistant] The Exile was a Force Void. Basically, she was a hole in the Force that drew on or "fed" on the Force powers of others. Kreia believed that, if manipulated properly, the Void within the Exile could grow to encompass everything, destroying the Force entirely. She had tried before with Darth Nihlus, but he turned on her.


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

[User] If the emperor was all powerful then why could vader kill him so easily?

[Assistant]
Several reasons:  First, the Sith seem to generally have less control over their force powers than the Jedi, relying more on raw power than precision.  As a result, when Darth Vader attacks the Emperor, the Emperor sprays wildly and is never able to refocus his lightening attack on Vader the way it was focused on Luke.

More specifically, Vader had Jedi powers at one point before he turned to the Dark Side.  We know from Yoda's example in the duel with Dooko that a sufficiently powerful Jedi can absorb and redirect the lightening attack.  Whether the latent good Luke senses correlates at all with the latent ability to use the light side force powers is unknown.  However, it is known that Anakin was a singularly powerful user of the force and if limited cross-morality use of that power is possible, then he would be the one who could pull it off.

Technologically, Vader was basically a man-shaped tank built by the same civilization who brought you the Death Star.  Their lack of design foresight aside, it is reasonable to assume that they probably put in a surge protector.

Finally, the Emperor himself was never really the most powerful of the Sith, that was always supposed to be Anakin.  Granted, the Sith Lord was an exceptional liar and manipulator, but he lost badly to Windu and barely fought Yoda to a draw, and neither of them were The Child of Prophecy.  We don't know to what extent Anakin's conversion into Vader may have diminished his force powers, but the starting premise that the Emperor is "all powerful" seems dubious at best from what we can gather from the circumstances surrounding his rise to power.


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

[User]
[Lion King] How the Hell did Scar make the river dry up?

Did he engage in short sighted agricultural irrigation practices?

[Assistant]
He didn't.  The river (and environment in general) dried up as a natural part of the cycle of drought and rain.  This led to a loss of vegetation, which then led to a fall in the herbivore population.  In the past, when Mufasa was in charge, the hyena population was kept in check, which meant that a drop in the number of prey animals wasn't a huge issue, since there weren't that many predators to feed.  Scar's reign, however, was characterized by an explosion in the number of hyenas, which led to a catastrophic collapse among the already-depleted numbers of the prey animal populations.  Before long, there wasn't any food available for any of the predators, including hyenas and lions.

When Simba seized power from Scar, he banished the hyenas back to their original, barren territory.  Lots of hyenas starved to death, but at least in the Pride Rock region, the herbivore population was allowed to recover, thanks to there now being much fewer predator mouths to feed.


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

[User]
ELI5: Why does the back usually hurt after standing up for a certain amount of time, but not after walking the same amount?

Edit: after standing up still*

[Assistant]
Standing in place is actually way harder for your body. The muscles in your lower back are always tense when you stand. Where as when walking, they get relaxed and then tense up again.
Imagine doing 20 pushups in 5 minutes. Now imagine doing 1 pushup in 5 minutes (staying low)


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

[User] [Star Wars] Why does Yoda say Luke needs to defeat Darth Vader to become a Jedi?

[Assistant]
He actually says he must *confront* Vader, not defeat him.

Anyway, t's the last trial he needs to undertake. Traditionally, Jedi had to take a number of trials before they became full-fledged Jedi - the trials themselves aren't standardized, but individual to each person - and Luke passed most of what the requirements were to be a Jedi, barring one last trial.

So at the time that Luke is getting ready to go to Endor, he's about to face the last trial before he can truly be called a Jedi.


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

[User] How do we know that animals like dogs cannot see color?

[Assistant]
First, dogs do see color.  But they have only two types of cones (the retinal cells that detect color) while humans have three.  So they don't have as good color discrimination as we do.

The most used method to determine this is to do behavioral experiments.  You can do things like deprive an animal of water and offer water from one of multiple locations after a flash of colored light, where the color represents the location of the water.

People have done VERY extensive experiments on the cone function of mice using techniques such as this.  You can measure sensitivity at any wavelength by adjusting the intensity of the stimulus.  Google 'cone function in mouse' and you will see tons of articles.

Most of our cones are in our fovea, the structure that detects fine detail in the center of fixation (where you stare).  Interestingly, dogs don't have foveas (the structure responsible for excellent vision in the center of fixation), they have something called a visual streak.  Birds of prey have two foveas, one for looking ahead and one for looking down to spot prey!


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

[User]
[LOTR] Smeagol and Deagol were Stoor hobbits that lived on the banks of the Anduin river. What happened to these stoor hobbits that lived outside of the shire?

The shire was officially colonized in T.A. 1601

But the events with Smeagol's birthday happened in T.A. 2463, which presumably meant that some of the Stoor hobbits still dwelt in the Gladden Fields, and this was after many stoors already settled the Shire. What ever happened to these Stoor hobbits that Smeagol came from?

[Assistant] The migration began a long time ago, but plenty of eastern Hobbits stayed behind. But they and the other hobbits migrated westwards to join the Shire in response to what eventually turned out to be the return of Sauron's empire.


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

[User]
Why are appetite suppressors so hard to discover and make useful for dieters when most side-effects of medication is 'loss of appetite?'

I've taken medication in the past that has completely killed my appetite. This seems to be a common side-effect of many substances, yet a pill to help people stop feeling so hungry is something that doesn't seem to exist and most diet pills have horrible GI side-effects.  Why does this continue to elude us?

[Assistant]
Layman here, but it's hard to find something that ONLY kills appetite. For example, adderall (levoamphetamine and dextroamphetamine salts), which is prescribed in the treatment of ADHD, kills the appetite, but it also causes euphoria, insomnia, mania, and can be harmful to your cardiovascular system. Same for ephedrine.

That said, for some severely obese patients, doctors may prescribe a medication for its off-label appetite suppressing effect.


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

[User]
How come I can't make a fist or squeeze my hands tight after waking up in the morning?

I don't mean the hand being numb from sleeping on it.

Is it simply that the body is so relaxed in sleep, it takes a while to regain control of the muscle? Because it seems like only my hands are affected.

Is there a name for the phenomenon?

[Assistant]
From Wikipedia on REM sleep:

"The release of certain neurotransmitters, the monoamines (norepinephrine, serotonin and histamine), is completely shut down during REM. This causes REM atonia, a state in which the motor neurons are not stimulated and thus the body's muscles do not move."

If you wake up early from a sleep cycle, these neuroinhibitors are still in you system making you feel lethargic and makes muscle movement very difficult.


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

[User]
[Cabin in the Woods] How would the Japanese office have accomplished anything?

It is made very clear in the movie that the five specific kids needed to fulfill their roles and die, with the exception of the last one, who doesn't have to die, just needs to suffer.  It's also made clear that there are other offices around the world, and that they are attempting to appease the same Old Gods, and all failed, thus putting all of the pressure on the Cabin office.  The only other operation we see, though, is the Japanese one, and there are none of the archetypes needed for the sacrifice, only a bunch of elementary school Japanese girls.  If they hadn't failed, and the girls had been slaughtered, what would that have accomplished, if the sacrifice had to be as specific as it was established to be; one might say that the characters were simply misinformed, but that can't be true either; if an indiscriminate massacre is all that is necessary, then the Cabin facility wouldn't have failed.

[Assistant]
**All information next is highly classified, any leak will be highly punished, read with caution.
**
Each office is placed in specified spots around the world where the distance with the Old Ones is small enough for the procedure be the most effective.
It's to remember that each spot also responds to a slightly different kind of Old One, and their power and needs have affected their surroundings since the times when they were still around; Making the necessary sacrifices and rituals different.
In resume, the old folklore of the place signifies a difference in the Old One residing underground, even if it's just enough to please one of them to keep them calm, each one takes pleasure in a different kind of sacrifice, some of them quenching their thirst with just a virgin as others need a small town to be reduced to gravel.


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

[User] [Harry Potter] What kind of products would wizard Billy Mays sell?

[Assistant]
HI EVERYONE BILLY MAYS HERE WITH EXPECTOXICLEANIARIMUS.

JUST ONE WAVE OF YOUR WAND AND FEEL THE CLEANING POWER OF EXPECTOXYGEN

FOR JUST 1 GOLDEN DRAGON YOU GET NOT ONE, NOT TWO, BUT 10! YES 10 BAGS OF REQUIREMENT FULL OF THIS BULLSHIT PRODUCT.


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

[User]
ELI5: Why is twitter so popular?

Everyone is talking about it, you even hear tweets mentioned on the news.  So whats so good about it?

[Assistant] Well, Twitter is a website where people can post what they're thinking, so long as it's short.  They can also post to it from their phones very easily, so it has become pretty common to post about what is happening around the person who is posting.  Sometimes people on Twitter see what's going to be in the news before the news people can get there, or sometimes they just say something really funny!  It can be pretty interesting to read.


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

[User] ELI5: A piece of toilet paper that has been used for blowing a nose could be put into a toilet or into a trash can (which is often right next to a toilet). This choice sends the toilet paper into two completely different waste streams. Which is the more environmentally friendly choice and why?

[Assistant] Toilet paper is made of short cellulose fibers specifically designed to disintegrate in water. Eventually it gets digested by bacteria in sewage treatment plants . In the waste basked, it ends up in landfills, and while since its cellulose it too will be broken down by bacteria it might take fractionally longer since the environment is inconsistent and less wet.


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

[User]
How does STD Transmission work?

In recent months, I've become curious about how STD's such as HIV, gonorrhea, herpes, etc are transmitted between partners. Withholding transmission mediums such as IV needles and the like, how does STD transmission occur during sex? More specifically, why are some STD's (such as HIV) more likely to be transmitted via (unprotected) penetrative sex than oral sex? My original intuition is that the infected bacteria only need to find an entry point into the body and at that point the person will become infected. Seemingly, this would make oral sex just as dangerous as penetrative sex. Obviously I am here to learn from individuals much smarter than myself so I look forward to your input. Thanks in advance.

[Assistant]
Infectious bacteria and viruses don't just infect "the body", but usually have specific body parts or cell types that they can survive and grow inside of. You can think of it similar to how animals can be the top predator in certain ecosystems but would be unable to survive in others. A polar bear from Canada could probably do pretty  well in Greenland, but if you put it in Egypt it wouldn't survive.

Similarly, some organisms can infect the cells of the reproductive tract, but can't survive in other areas. We call these "sexually transmitted infections" because this is the main way that they get spread, but it isn't the only.

HIV can survive in reproductive cells and the rectum, but is quickly killed within the mouth. Its ultimate target is immune cells, so you can also get infected if it is directly put into the blood stream. So oral sex is not a risk factor for HIV, but vaginal sex, anal sex, and needle-sharing can lead to infection.

Gonorrhea infects the reproductive tract, but it is also pretty good at surviving inside the throat. So oral, anal, and vaginal sex are all possible of transmitting it. Unlike HIV, it usually doesn't survive anywhere else in the body such as the blood, so you are unlikely to catch it via sharing needles.

Conversely, viruses that cause the common cold can easily survive in the throat, but they would not be able to survive in the reproductive tract. So kissing can transmit a cold virus, but oral sex is not going to.

Hope this answers your question!


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

[User]
ELI5: During mass network outages, how come credit works but not debit?

If youre Canadian, youre probably experiencing a network outage right now.

[Assistant]
Because it's a different network. No money actually moves when you do a credit transaction. You tell the credit company to give money on your behalf. It's done just over the internet and can be queaed up and released. Card transactions get verified and money "moves" immediately.

So they're different networks and if the core goes down the whole thing breaks.


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

[User] ELI5: Why don't cruise missiles render bomber jets obsolete?

[Assistant]
I think the main advantage over a cruise missile is that having an aircraft "on station", in other words, nearly right over top of the target, allows for more flexibility in general. If the target moves ever so slightly, then adjustments can be made right then and there. If the target is a building and 80 school children walk out of it, it's going to be a lot harder to stop a cruise missile than an aircraft.

Overall, in Iraq and Syria, the environment on the ground is so fluid and changing that lobbing cruise missiles will work only some of the time.


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

[User]
I believe there should be a cap on the number of children a family can have. CMV

We as a race seem to be overpopulating the planet. Certain families have so many children that they cannot provide for them all. Resources are limited, and if we were to put a limit on how many children a family can have (like what they do in China), the quality of life for those who are born into the world would increase, especially in countries/regions where resources are scarce.

[Assistant]
Areas of the planet in which a limit on children could be applied *are not* contributing to global overpopulation. In fact, Western 1st-World democracies are experiencing *negative* population growth (or at least a decline in rates of population increase) as a result of expanding rights for women, increased access to family planning, and the necessity of a 2-income family to support a 1st World lifestyle.

The areas of the world that are contributing to global overpopulation lack the central governmental authority to implement or enforce a limit on reproduction. Tribal, familial, or local systems of governance have no vested interest in limiting the growth of their population. In fact, due to extreme infant mortality and an agrarian subsistence lifestyle, these people *rely* on large families for their survival. Should the UN or the US mobilize troops to Sub-Saharan Africa to forcibly sterilize women?

The fact is that, if our use of global arable farmland and fresh water was optimized, Earth would be able to support up to 16 billion people: 9 billion more than our current population. The problem isn't that poorer countries produce too many people: the problem is that Western societies consume a disproportionate amount of resources relative to their population. Coupled with our declining birthrates, our ever-increasing consumption, and our increasingly service-based (as opposed to production-based) economies: we *need* poor countries to keep increasing their populations to produce our goods, mine our resources, and immigrate to take low-skill, low-paying jobs - in order to sustain our current standard of living and our aging population.


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

[User]
ELI5: Is it better to brace your body or stay loose in an accident/fall?

You ever go fly on a plane and the first thing they tell you in a crash is 'brace position', brace yourself against the seat etc to minimises injury. But then on the other hand you hear these miracle stories of cats surviving 20 foot falls because they stay loose and floppy when they land, or those guys who fall from huge halfpipes and can land that 'floppy' way to minimise damage. But in a car accident you are told to brace back against your seat? So which is better?

I can imagine bracing would be better for your brain. Minimise concussive damage and whiplash/neck trauama, but may increase the likelihood of broken bones?

[Assistant]
Obviously every crash is different and some things will work better in one situation than they would in another, but the brace position in an aircraft crash, or bracing against a car seat have a very specific purpose.

In any collision there are multiple impacts.  In an aircraft crash there is the impact of the plane hitting the ground, you hitting the inside of the plane (seat, floor, controls, whatever the object is), and your internal organs (biggest concern being the brain) hitting the inside of your body.

The brace position is an attempt to remove, or at least lessen, the second of those impacts: you hitting the inside of the plane.  By placing your body against the seat in front of you, or against your legs (depending on the position used) you are already against the object you are likely to hit and will therefore push against it instead of impacting it.


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

[User] ELI5: why are there two chains of command in companies? There's the CEO, CFO, COO and the President, Exec VP, and VP line. What's the difference between a president and a CEO?

[Assistant] The role of the President (and basically only the president) will vary wildly between businesses. CEO is always the top-level executive officer, should the title exist at all, commonly assisted by a CFO, COO, and maybe some other C-level executives like CIO. In companies with both President and CEO titles, the president is often the public face of the company. This could be bundled together with the CEO or COO position, given to the Chairman of the Board, etc. Alternatively, they could have a president that acts as one of the steps in-between VP and CE. Other times, the organization will avoid CEO altogether and use President as it's chief executive.


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

[User]
Eli5: Why does WD 40 work? And why does it have such a huge scope of application?

It just tried it and it's insane, now I want to know how it works.

[Assistant]
WD-40 isn't actually a lubricant, it behaves more like a solvent.

It doesn't make things slippery, it cleans off the stuff that keeps things from being slippery.

So if your door hinge squeaks, instead of covering the hinge in lube, it's kinda like you're *cleaning* the hinge instead.


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

[User]
[Marvel] Is Deadpool's ability to sense the Fourth Wall tied to his healing factor?

I haven't seen the film yet, but in the trailer for *Deadpool* he cracks a joke about Green Lantern before undergoing the Weapon X .... process.

I've seen a lot of people on here claim that his comments are either insanity caused by his constantly-healing brain cancer, or a secondary mutant ability, kind of like telepathy.

I know in the comics he's had his healing factor removed a bunch of times, but the only one I've actually read was *Thanos vs Deadpool*, where he died too quickly to say anything.

Has he lost his fourth-wall-breaking before in the comics when his mutant abilities were neutralized?

[Assistant] Deadpool is insane. Him believing he's in a comic book and making all those 4th wall breaking references is part of his insanity, he just happens to be right. It's like a paranoid schizophrenic who just happens to really have people watching him.


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

[User] [Star Wars] What did the average citizen know about Darth Vader and the Emperor?

[Assistant]
It depends on the planet. The media sites everything the Empire did to be good. Even the Death Star was shown as a tool to destroy potential hazards in the space lanes. The Emperor was known as the old successful Chancellor that led them through the war and that survived the Jedi attack. Darth Vader was shown as his right hand, though he was rarely seen and those who witnessed him in real life learned better.

Unfortunately, the average citizen doesn't know much.


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

[User]
ELI5: Why is the difference between the sum of a whole number's places and the number itself is ALWAYS a direct multiple of 9?

For example let's assume a number 142.
So 1+4+2=7

142-7=135,  which is a multiple of 9.

[Assistant]
In the decimal system (which is the one we use), the places of a number are how it's written as a sum of powers of ten. For example 142 = 110^2 + 410^1 + 210^0

So if we apply your operation to a number that's written "abc" (**a** is the first digit, **b** is the second digit, **c** is the last digit), a little algebra can show us how it works:

(**a**100 + **b**10 + **c**) - (**a**+**b**+**c**)

= **a**100-**a** + **b**10-**b** + **c**-**c**

= 99**a** + 9**b**

and now we divide by 9:

(99**a** + 9**b**) / 9 = 11**a**+**b**.

Since a and b are whole numbers, the final result will always be a whole number, so it's divisible by 9.

___

ELIhatealgebra:

Let's take a big number, for example 7342.

It's actually made of a group of 1000 sevens, a group of 100 threes, a group of 10 fours, and a single solitary two. That's what all big numbers are, the digits of a number just tell you exactly what groups of 10, 100, 1000 and so on it is made of! It's what we call the "decimal system", or "base ten".

If you remove one instance of each of the digits, well you're left with 999 sevens, 99 threes, and 9 fours! (You remove the single solitary two, so there are no lonely digits left). So you're left with a number that is just a collection of groups of nine, ninety-nine, nine-hundred-and-ninety nine digits! These groups are all multiples of nine! So the number itself is, too a multiple of nine! (because if you divide each of the groups it contains by nine, all groups make "good" divisions with no leftover! 99/9 = 11, 999/9 =111 and so on, they'll always divide neatly).


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

[User]
ELI5 Why are condoms only 98% effective?

I just read that condoms (with perfect usage/no human error) are 98% effective and that 2% fail rate doesn't have to do with faulty latex. How then? If the latex is blocking all the semen how could it fail unless there was some breakage or some coming out the top?

[Assistant]
Keep in mind, thats the ANNUAL fail rate. So, they prevent pregnancy in 98% of couples using exclusively condoms for a year.

Mistakes happen, things break or slip off. Its still vastly better than any other non-hormonal method.

Edit: Yeah, Im wrong about this second point. Condoms are great, but there are other great non-hormonal methods, too.


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

[User]
ELI5: Why are humans noses pointed down where nearly ever other animal's nose is pointed forward?

*every not ever.

[Assistant]
There's a lot of exceptions to noses-pointing-forward. Elephants, tapirs, aardvarks, anteaters, many fish, and so on.

But those that have noses that do point forward, which includes most herbivores and omnivores that graze, usually walk on all fours, not on two legs, and tilt their heads toward their food by bending their neck, not lifting it to their face. This means their forward-facing nose is closest to their potential food.

It's impractical for humans to bend down and sniff something on the ground so we evolved the alternate strategy of bringing our potential food to our face using our hands instead, placing our nostrils closest to our mouths by bending our noses down.


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

[User] When two balls are released on a Newton's Cradle, why is the momentum transferred to the two at the end and not just one (giving it a greater speed)?

[Assistant]
It needs to conserve momentum and kinetic energy.

    p = mv
    ek = 1/2 mv^2

As you adjust the mass and velocity the momentum and kinetic energy change by different amounts. Because they must be equal on both sides of the cradle, the only solution is that the same amount of mass moves at the same speed.


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

[User] Why do western economists call their countrys domestic product gross?

[Assistant] In german, "nice" is translated to "Nett". Since Gross Domestic Product after taxes is nice income, we call it Net Domestic Income (lose a t for making it english). But since we don't like paying taxes but before it being nice we do have to pay taxes, we find that gross, and so that's why it's Gross Domestic Product. For the same reason we also call a dozen dozens a "Gross", because squaring 12 is kinda icky.


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

[User]
ELI5 How do coffee machines heat up water so fast?

Within just a few seconds of pouring cold water, it's able to pour hot coffee within just a few seconds. Much faster than a kettle. How?

[Assistant]
It has to do with volume of water being heated at any one time.

A coffee machine runs a small amount of water continuously over a heating "element" - the part that gets hot when you run electricity through it. As a small stream of water passes over or next to the element, it touches so much of the element that the temperature drives up very quickly. A few teaspoons of cold water in becomes a few teaspoons of hot water out, over and over, because the drip rate is highly controlled.

However a kettle has a *large* amount of water with a *small* heating element in it, usually near or under the bottom of the water-holding part. Now the water next to the element gets heated, sure, just like above. But then "convection" (similar to currents in the ocean) causes that hotter water to move away and mix with all of the other still-cool water in the kettle. So instead of a few teaspoons driving temperature up quickly, a large reservoir constantly mixes still-cool water with freshly-warmed water.

So in the same way a piece of paper burns quickly but a stick of wood doesn't, the water in the kettle takes a lot longer to come up to temperature because there's so much more of it and it all needs to get heated up before it will boil.


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

[User]
Is a key that cannot unlock anything still a key?

I have an presentation to do in school on this question. My own thoughts are that when the key loses its ability to unlock things, it's no longer a key. My teacher said that it would be good if I could talk a little in the terms of how we can know it's a key at all etc. Would appreciate some help and thoughts from you redditors. (I apologize for my bad english, I hope you can deal with grammar errors.)

I'm not really out for answers on the question, I would greatly appreciate any philosophical theories on this subject though.

[Assistant]
There are prima facie reasons to think keys without proper locks are still keys, and these reasons come from way 'key' is used in ordinary language. (These things might turn out not to be *real* keys, but that conclusion has to come from somewhere else.) Firstly, think of a key for which no lock has been made. A lock could still be made which that key would open. Secondly, think of a key whose lock has been lost - maybe the key was buried in a drawer for decades whilst the door was replaced. These keys don't have locks and we still call them keys.

One simple way to define keys is by their functional roles - keys are what they are in virtue of what they do, namely open locks. If natural language has any weight, then the above shows that this is simplified, if not wrong, since we call things 'keys' even when they don't open locks. Perhaps, then, keys have to have the capacity to open locks, or have once been able to open some lock. Again that looks simplified or partial (couldn't any object open a lock provided we design the lock to suit that object's shape?).

Your theory suggests things gain and lose key-ness: a things becomes a key when its lock is made, and is no longer a key when its lock is destroyed. This is clearly at odds with common sense, and we typically don't talk about keys in that way. It also suggests that the following situation could occur: you find a key-shaped object and genuinely don't know whether it is really a key or not. We are all key-skeptics until that object is used in the proper lock. That seems weird, and to make that argument you have to claim that we don't know what we're talking about when we talk about keys. That sort of thing generally strikes me as suspicious.


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

[User] ELI5 - what determines whether an adjective is enhanced with more or -er?

[Assistant] Its almost always the amount of syllables. One or two syllables will usually have er (happier, slower, slimmer, etc.) while three or more will have more (more delicate, more agreeable, more extemporaneous, etc.) hope that helped!


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

[User]
Why do neutrons shoot through dense material, but get reflected by softer material during Radiography?

I understand that it has to due with the transfer of momentum from the particle colliding with the nucleus of the atoms in the material, but I'm having a difficult time understanding why it shoots through the dense solid. Why doesn't it bounce off of the surface similar to a pool ball hitting the side of the pool table?

[Assistant]
Actually, they don't "shoot through" heavy materials.  They "bounce through" them.

As a matter of fact, heavy nuclei have larger scattering cross-sections than light nuclei.  The difference is what happens when the neutrons hit those nuclei.  If you have a light nucleus (say an H-1 nucleus), then that mass is about the same as a neutron.  So when they hit, it's like 1 billiard ball hitting a stationary one--most of the energy gets transferred over to the hydrogen nucleus and the neutron loses most of its energy.  After only a very small number of these collisions, the neutron is moving as slowly as the protons themselves are moving due to heat (we call this "thermal energy" and it's generally 2200m/s or 0.0253 eV, compared to the energy neutrons emitted from fission have, about 2 MeV, 100 million times more).  At this low energy region, other neutron interactions, such as neutron capture, are much more likely to occur, so the neutron is very likely to be captured.

However, imagine a soccer ball kicked at a much more massive medicine ball.  The soccer ball will bounce off and transfer a *little* bit of momentum to the medicine ball, but will mostly just bounce off, losing only a very little amount of energy.

Now in the case of soccer balls and medicine balls, the mass ratio is about 2-20.  In the case of a neutron and a Pb nucleus, it's a ratio of about 200.  Almost no energy is transferred at all.

So if you have a light nucleus material, then the neutron will hit it, bounce around a bit, and get captured pretty soon (assuming there's something with a decent capture cross-section around).

But if you have a heavy nucleus, then the neutron will hit it, bounce around, bounce around, bounce around, bounce around, bounce around, and just bounce and bounce and bounce.  Now, in actuality, if you have for example a large amount of lead, then most of the neutrons will end up bouncing back towards you, but still, a very large considerable amount will bounce around and go through.


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

[User]
Can any organisms see non-electromagnetic radiation?

Some examples would be cosmic rays, neutron radiation, alpha radiation, beta radiation, muon radiation, and antimatter radiation.

Some related questions: How is non-electromagnetic radiation detected, and would it ever be evolutionarily beneficial?

[Assistant]
No known organism. There's no source of nutrition that emits or reflects these types of radiation any differently from the background.  Same goes for sources of danger - there are no predators that emit lots of beta particles, for example.

As a result there is no evolutionary benefit to detecting these kinds of radiation - they carry no information that is useful to biological life.

Since no life-form  has evolved the ability to detect these types of radiation, there is also none that evolved the ability to emit them. No point in emitting something nobody can detect.


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

[User]
Do we know of covid-19 reservoirs in wild animals yet?

Knowing that Denmark had to cull their mink population because they contracted covid-19 and knowing the role of wild bird populations with regards to influenza, what do we know of similar wild animal populations that could play an important role as virus reservoirs for covid-19 in the next couple of years? Thank you very much!

[Assistant]
Well, the virus probably originated in bats, so those bat populations probably still harbor the wild-type of the virus and/or its close relatives.

Also this coronavirus is demonstrably capable of jumping between species, so it should not come as a big surprise if the virus spills over from humans into other animal species, and we should be actively monitoring for such events.


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

[User]
[Pirates of the Caribbean] Why did the pirates of the Black Pearl react in pain whenever they got stabbed or shot?

The curse they have doesnt allow them to feel anything. No pain, taste or touch.

[Assistant] Look, Barbossa is very clearly full of shit. Yeah, he tells us that he doesn't feels anything, but that is contradicted by literally everything we see about the behaviour of him and the other pirates. They absolutely have a sense of touch and pain. Maybe they can't derive enjoyment from it in anything other than a very shallow way, but there are a lot of scenes  that only make sense when the pirates are able to feel.


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

[User]
Is there any talk of scaling back PhD programs in light of the higher ed bubble collapsing/demographic cliff?

For example, the academic job market has been bad for decades but has gotten worse and worse as the predicted wave of retiring professors never materialized, research funding has been flat since the end of the Cold War, and we keep pumping out more PhDs every year with a relatively fixed number of faculty positions available.

Now we have COVID popping the higher ed bubble ahead of schedule and the demographic cliff, the situation is going to get historically bad.

Is there *any* talk in your departments of admitting fewer grad students to avoid contributing to the problem, or is cheap grad student labor just too valuable to pass up?

Do faculty in your area tend to dissuade people from going to grad school or what?

EDIT:

I retract the claim about funding after the Cold War, its more complicated than that.

[Assistant]
I hope to see them start saying the quiet part out loud: most grads never go into academia, and it's been that case for some time.

And programs start putting far more focus on helping students build pathways via the translatable skills they acquire.


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

[User]
ELI5: What does it mean in Quantum Physics when something is changed by watching it?

How does that even work?

[Assistant] Consider that this can happen on a larger scale as well.  If you stick a regular meat thermometer into a pool, the overall temperature of the pool will not change.  If you use the same thermometer to measure the temperature of a tiny drop of water, the thermometer's temperature will change the temperature of that little drop.


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

[User]
[DC] How can Superman exert more force than he could possibly take in through absorbing sunlight?

Superman is powered by the sun, so how can he use more energy than the sun produces in it's lifetime? He can punch with more force than a supernova, yet he couldn't possibly have absorbed that much energy from the sun.

[Assistant]
The physics of Superman's powers are poorly understood even by top scientists. While you might be overestimating the force of his punches (he certainly doesn't punch that hard during normal circumstances, though when fighting foes like Darkseid or Doomsday he might), it's true that even if he functioned as a 100% efficient solar panel he'd run out of energy fairly quickly.

I see two potential explanations for why he doesn't drain like a battery, though because the man's so busy it's understandable that scientists haven't been able to test either of them.

The first is that, as an extension of the unconscious telekinesis that allows most of his feats of strength when dealing with structurally unstable objects, he can siphon energy as needed from the sun that would have otherwise escaped into space, essentially acting as a telekinetic dyson sphere. He could also soak up energy from other stars this way, when he goes on interstellar journeys.

The second might explain where the excess energy comes from even outside what could be gained from real-time sun consumption: he could tap into the speed force. Those races have shown that Superman is almost as fast as the Flash, and Star City scientists have heard about and begun to try to analyze the Speed Force that lets the Flash use way more energy than he takes in from food. It seems likely to me that Superman breaks thermodynamics using the speed force in the exact same way.


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

[User]
How do gland problems stop people from losing weight?

If I burn 2400 calories in a day, but eat only 1900, why wouldn't the 500 extra calories just come out of fat like normal?

[Assistant] Yes.  But the signals being sent to the brain can cause over-eating or burn rate issues (imagine feeling sluggish after walking 5 minutes-- how would you burn 2400 calories?).  Metabolism (the body's natural burn rate) can widely vary based on age, gender and genetics (see Hypothyroidism).  So effectively in equation terms, yes, if you managed to burn 2400 calories and only ate 1900, you would lose weight; but easy burning is the pretty much the key glandular factor issue.


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

[User]
This may sound stupid, but I'm genuinely curious: Why do mirrors make things appear flipped horizontally, but not vertically?

Like, why don't things appear upside down but they are flipped left to right?

[Assistant]
This is actually a really cool concept because it's very unintuitive. The answer is that mirrors *don't* flip left and right (or up and down). You can see this if you just think carefully about it when you look in the mirror. If you raise your right hand, the image of you raises the hand *on the right side of the mirror*, not the left. When you hold a book up to the mirror, the words appear backwards to you, but the letters that appear on the right side of the book (when looking at the book from behind, facing the mirror) appear on the right side of the mirror, and the same for the words on the left side of the book.

In fact, what mirrors flip is front and back. When you're looking at a mirror you're facing towards the mirror, but the image of you is facing back in the opposite direction. Thus, when you raise your right hand, the image of you raises *its* left hand (even though that's the hand on the right side of the image). That's why we get confused into thinking the mirror flips left and right.

With the words on the page, they look backwards to use because we're holding the book facing away from us. You can check this by taking a piece of light paper with some words on it and holding the words facing away from you up to a light. You should be able to see the letters through from the back side of the paper, and it will look just like the image you would see if you held it up to a mirror.


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

[User]
[Back to the Future II] What makes flying cars fly and hoverboards hover?

As a bonus question, what made the pizza grow so quickly? And how could such a thing be pre-packaged?

[Assistant]
Anti-Gravity technology. Both have some sort of levitation...things...underneath that hold them from the ground like magnets with the same polarity repel each other and while cars have thrusters at the back to provide momentum boards need to be manually propelled.

The pizza was dehydrated then re-hydrated.


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

[User]
[DC] Would riding a bike make the Flash faster?

Would he get a similar boost in speed as a normal human, or would the bike's wheel not turn fast enough and drastically slow him down? What if the bike were indestructible and it's wheels were able to turn arbitrarily fast?

[Assistant]
Flash controls something known as speedforce which is an energy that directs motion in the DC universe and is the source of his ability to ignore several laws of physics such as friction and inertia to move incredibly fast.

He can modify other objects too so if he applied it to the bicycle he could definitely see his speed improved by the wheeled advantage though it would probably be annoying to carry around and in combat. Particularly if the advantage isn't really felt by him that can travel from place to place in picoseconds.

If he doesn't apply the speedforce energy to the vehicle, the wheels and gears will probably break down or catch fire from the friction as it tries to keep up with Flash's speed.

Also must consider whether applying this "speedfore aura" to the vehicle tires him more than just running naturally.


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

[User]
[Lord of the Rings] What does the One Ring actually do?

We know that it turns you invisible, but that can't be the only reason everyone wanted it.  What would it have done for Gondor?  What would it have done in Sauron's hands?

[Assistant]
It literally has a piece of Sauron's essence in it... and Sauron is essentially a low tier god (demigod, depending on your definition). Its powers are many and great and terrible (ooooooh!). The "invisibility" it bestows is really just the ability to walk in the "wraith world," a realm of ghosties and ghoulies and so on.

Now, let's examine the 19 other rings of power: to the Elves, they granted the ability to preserve their little enclaves, giving the unchanging immortals respite from the ever-changing outside world. The Seven given to dwarves apparently gave them the power to seek and find wealth. And the Nine given to Men gave them the power to evade death, the curse of mortal men (not *happily*, but they did).

It's hard to say whether those rings were deliberately made with those abilities; they Elven smiths who made them probably intended for them to remain with the Elves, but Sauron was manipulating the whole deal from the start. In any case, it does seem that each batch of rings was tailor made to suit the desires and wishes of the holders. So, yeah, they're a lot more powerful than a mere invisibility cloak, and the One probably most of all.


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

[User]
How can light move at the speed of light if it is massless?

If p=mv, and m=0, then mustn't p=0 too?

[Assistant]
The equation p = mv only applies to objects with mass that are traveling at low speed. The more general equation for objects with mass is p = gamma mv, but this is still only for objects with mass. An even more general relation that is valid for objects with mass and without is:

p^2 = E^2 /c^2 - m^2 c^2

For objects with no mass, we plug in m = 0 and find:

p = E/c

As we see, it is the energy of light that gives it momentum and not its mass.


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

[User] ELI5: What's the difference between a cog and a gear?

[Assistant] In the strict sense, a "cog" is a tooth on a wheel. A cogwheel is any wheel with teeth. A gear is a cogwheel used to mesh with another cogwheel. And a sprocket is a cogwheel that links to another cogwheel by means of a chain.


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

[User]
[Harry Potter] Why was there no foreign response to Voldemort?

Specifically meaning countries that don't neighbor Hogwarts.

[Assistant] Why was there no foreign response to Hitler before he invaded Poland? Because "Yo country, yo problem." Most people don't want to get involved in the political issues of other countries, and generally only do so once their own interests become threatened.


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

[User]
How do we communicate wih people who are blind and deaf?

Serious question...How are we able to teach people to attain some autonomy if they cant hear or see us?

[Assistant] First of all, it is very uncommon to be born both deaf and blind: mostly people are born deaf and gradually become blind or vice versa. Therefore, they start with learning special sign language and/or braille at a young age. Communication with deaf-blind people usually goes through special interpreters (deaf-blind); they make signs with the hands of the deaf-blind person, or spell letters in the hand of the deaf-blind person. In answer, they do the same. Communication therefore is slow but not impossible. Source: sister is a deaf interpreter who did a minor in deaf-blindness.


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

[User] ELI5: Why is having home-field Advantage so significant?

[Assistant] Familiarity with the pitch and playing surface, crowd support and less travel. Lots of professional athletes are also superstitious, it's easier to do your routines in a familiar place. Also, away dressing rooms are rarely as nice as home ones, which can psychologically make you feel better.


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

[User]
[Fallout 4] When I awoke in the Commonwealth, I met some terrifying people and things, and tried to kill them. I've since traveled throughout Boston, wiping out stronghold after stronghold, and these terrible things just keep getting stronger. What gives?

A few weeks ago I woke up in a vault outside of Boston.  While trying to find a family member of mine, I ran into people dressed in rags and armed with pistols made out of pipes.  Giants wielding 2x4s.  In the past weeks, I've killed hundreds of these monstrosities.  I've helped large, friendly groups advance their causes.  But this morning, I came across yet another raider encampment, except this time several of the raiders were wearing power armor and firing .50 caliber sniper rifles.  Have I accidentally set off some sort of terrible post-war arms race?

[Assistant] Only the strong survive, and you are driving it. You killed off all the wannabes and losers long ago, now the elite remain. Plus stories of the Commonwealth a spreading, only the baddest of the bad can make it.


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

[User]
ELI5 Why do spiders not bleed out and die when losing a limb?

As a human if I lost a limb I would most likely bleed out and die within minutes if I didn't get medical attention but spiders are like "Oh no... Anyway..." And they just keep on trucking. Why is that?

[Assistant] Because arthropods dont necessarily use blood to circulate oxygen throughout their bodies.  In ELI5 terms, they instead have small holes through their bodies for oxygen to enter directly and spread locally.


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

[User]
Eli5: Why does meat from different animals taste so different? If its all muscle shouldnt it be pretty similar?

I can reason through cow and fish tasting different but not cow and pig.

[Assistant]
Diet, environment, DNA and activity level will have an enormous impact on the taste of individual meats.

There are times where two animals of the same species will taste different depending on how the individual animals grew up.


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

[User] ELI5: Now that there are so many ways to share and send data, is there any actual reason other than people being unwilling to try out new technology for faxes to still be used?

[Assistant] Yes. In Australia and many other countries faxes are an accepted form of legal communication. Faxes leave records and are very difficult to tamper with whereas this is less the case for things like email. Additionally, lots of jurisdictions still don't recognise the legal authority of digital signatures and such whereas in the case of a fax, you're still submitting electronically but pen is put to paper.


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

[User]
Where does the Fed's $1.5 trillion stimulus come from?

With the Fed "injecting" $1.5 trillion via repo's in response to the Covid market plunge, I'm realizing I don't know where that money comes from.

When the Fed does this, is that tax revenue they're using? Or are they printing that money? Or it just digitally created into existence?

Where does the Fed's money come from in these situations?

Much of the public (progressive) response is "look how easy it was to come up with $1.5T when wall street needed it, but we can't do that for healthcare, loan forgiveness, etc.?"

Is that a fair gripe?

[Assistant]
The money is newly created, as the Federal Reserve has the authority to do that.

>Much of the public (progressive) response is "look how easy it was to come up with $1.5T when wall street needed it, but we can't do that for healthcare, loan forgiveness, etc.?"

>Is that a fair gripe?

No, the Federal Reserve does not deal with those areas. Also these are short term operations, so the money will be paid back relatively shortly.


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

[User]
CMV: The biggest challenge to affordable healthcare is that our knowledge and technology has exceeded our finances.

I've long thought that affordable healthcare isn't really feasible simply because of the medical miracles we can perform today. I'm not a mathematician, but have done rudimentary calculations with the statistics I could find, and at a couple hundred dollars per month per person (the goal as I understand it) we just aren't putting enough money into the system to cover how frequently the same pool requires common things like organ transplants, trauma surgeries and all that come with it, years of dialysis, grafts, reconstruction, chemo, etc., as often as needed.

$200/person/month (not even affordable for many families of four, etc.) is $156,000/person if paid until age 65. If you have 3-4 significant problems/hospitalizations over a lifetime (a week in the hospital with routine treatment and tests) that $156,000 is spent. Then money is needed on top of that for all of the big stuff required by many... things costing hundreds of thousands or into the millions by the time all is said and done.

It seems like money in is always going to be a fraction of money out. If that's the case, I can't imagine any healthcare plan affording all of the care Americans (will) need and have come to expect.

Edit: I have to focus on work, so that is the only reason I won't be responding anymore, anytime soon to this thread. I'll come back this evening, but expect that I won't have enough time to respond to everything if the conversation keeps going at this rate.

My view has changed somewhat, or perhaps some of my views have changed and some remain the same. Thank you very much for all of your opinions and all of the information.

[Assistant]
The biggest problem with affordable healthcare in the US is its current delivery system. Too many people conflate healthcare with health insurance. You can't go to your local Aetna office and get a script for your allergies or a check up.

The vast majority of healthcare is not paid for by individuals, it is paid for by third parties such as insurance companies or the government. Due to a consolidation in buyers and a disconnect between the users of healthcare and the payers of healthcare, "retail" pricing of healthcare has exploded.

Let's say you need an MRI. The true cost of the MRI is $100. To make a profit, the provider of the MRI needs to make $150. Now, insert the insurance company which demands a 70% discount on this procedure. The provider can't give a 70% discount on $150 as that would make it untenable financially, so they mark the procedure up to $500 in order to allow for this discount to their best customer. This is how a $100 procedure becomes unaffordable to the average consumer. This is why aspirin cost $5 per pill at the hospital, and $.25 a pill when you buy it over the counter at the gas station.

So, what about really expensive, life saving transplant procedures? Well, this is what insurance SHOULD be for. When we buy insurance on our cars, that insurance does not cover oil changes, new tires, a battery, or other ongoing common maintenance. It covers you in case of a catastrophe. The insurance company is able to offset the money out on cars that are wrecked by the money in on all those people who carry insurance to mitigate their financial responsibility in case of catastrophe but who never suffer one. Using this analogy, if our car insurance covered oil changes, then it is quite possible an oil change retail price would skyrocket to abut $100 in order to allow for a 70% discount on the service for the primary payer, the insurance company.

As long as we maintain these barriers between providers and consumers (ask your doctor how much a procedure costs next time you are in for a visit) we will suffer retail pricing on healthcare that is unaffordable.


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

[User] ELI5: Why are graphing calculators so big and bulky when they don't have anywhere near the computing power of a much thinner smart phone?

[Assistant] Graphing calculators aren't really bigger than they need to be. You can only make it so small while still having enough surface area to fit all the buttons. They probably *could* make them smaller, to a degree, without much change in cost of production, but people would likely find them too cramped to work with. The smaller and closer together things are, the harder they are find. There needs to be adequate spacing between the buttons to "feel right" both tactilely and visually.


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

[User]
ELI5: How do radio stations decide what songs to play?

Does calling in for requests actually do anything? What's to prevent DJ's from playing two hours of the same artist?

[Assistant]
I work in radio in Canada, and this is how we go about getting music on the air.

Programming a radio station is a rather intricate process. There are a lot of factors that go into what songs are played on air. Most radio stations will do music surveys and ask their listeners to vote on what music they would like to hear or do some sort of market research. This doesn't guarantee those songs will be added but it gives the station a good idea of who is listening and what they want to hear. All radio stations also have access to BDS a tracking site that shows where songs are charting, what stations are playing what songs and how often they are spinning. Most stations have "mentor stations" (stations with similar format) that they monitor to see what they are playing, how often etc.  Once a Music Director decides to add a song it goes into a music scheduler program, we use Music Master.

With a music scheduling program, all songs are categorized based on the format of the station. For example, High Rotation, Medium Rotation, Songs to play only overnights or on weekends etc. These categories can be whatever the Music Director likes. Then rules are set in place. This helps with the "flow" of the station. The rules dictate how many of each category are played and in what order. In an hour play 3 songs from "A Category", 2 from "B Category", 1 from "C Category" and every other hour play 1 from "D Category" etc. Other really important things to work out are things like artist separation (how often you hear the same artist) and song separation (how often you hear the same song). In a top 40 station, this is VERY important as the stations playlist is generally pretty small. For example. Taylor Swift can play once every hour, but her song Style can only be played once every 2 hours. Another example of a rule could be that you don't play two slow songs back to back.

From there the magical scheduler program compiles a playlist or "log" and the music director then goes over it to make sure no rules are broken. They can manually tweak it too.

Seeing as how it's such an intricate process, a DJ who doesn't follow the log, or decides to keep adding songs to play what they want, most likely will be fired as they are breaking program rules that have been carefully selected. However, requests are legit (assuming you call with requests that fit the stations format ie. you aren't asking for AC/DC on a Top 40 station). If a station takes requests, most decide to do request hours. Which basically means they have created an hour of programmed music, but there are spots where the DJ can insert tracks or replace tracks if they get a request. The only challenge is that the DJ still has to abide by the rules in place (ie. can't play two songs back to back. Have to watch artist and song separation etc.).

That is a rather simplified version of how programming of a station works. It's very complicated. Lots of rules/formulas go into programming.

TL;DR - Rules are used to program a station, but requests do work.


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

[User]
James Ladyman made me lose my groove

I've never really been a metaphysics guy, but then I read some Aquinas and Loux's *Metaphysics: A Contemporary Introduction*.  For a few weeks, I was all about it.  Then I read the opening chapter of Ladyman's *Every Thing Must Go* and despaired.

Metaphysics people: Is current academic metaphysics as bad as Ladyman implies? Should I divert from metaphysics and work through a physics textbook first?

My primary metaphysical interest has been causality, and my impression from bad internet arguments is that thinking about causality purely from a science background leads to sloppiness and embarrassment.  Therefore metaphysics.

[Assistant]
Have you read Chalmers' et al. *Metametaphysics* yet?  It gives a good survey of different positions on (the meaning, aim, status, and promise) of metaphysics.  Mostly from an analytic perspective, but in a broad way that includes, e.g. engagement with folk like Aristotle and Heidegger.

Loux does a great job representing something like the mainstream analytic project, but we shouldn't confuse that for realist accounts of metaphysics broadly.  Lots of people are (like Ladyman) critics of mainstream analytic metaphysics, while still defending robust projects for metaphysics, and of a type which isn't scientific or naturalized (in Ladyman's sense).  Arguably, there is some significant violence done in thinking of Aquinas and Loux as engaged in a single project, to which someone like Ladyman is opposed.  The specifics of mainstream analytic metaphysics are very much response to the particular developments of 20th century philosophy.


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

[User]
If photons are smaller than atoms, why don't they pass through solid matter?

Aren't atom's mostly empty space, between the nucleus and the electrons? Shouldn't photons pass through those spaces and penetrate basically any form of matter?

[Assistant]
The closest thing to "size" for a photon is its wavelength. Different types of light have different wavelengths: x-rays have really short wavelengths, while radio waves have really long wavelengths. Visible light is somewhere in the middle.

If the wavelength is small compared to whatever we're dealing with, then you can treat the photon like a particle - i.e. it's a "bullet" that either hits, misses, or bounces off whatever we're dealing with. Visible light is 100s of nanometres in wavelength, which is way smaller than say, a window, and so you can think of it as a bunch of light "particles" flying towards the window: some of the particles go through the window, some bounce off the frame etc.

But if the wavelength is *big* compared to whatever we're dealing with, you really need to treat the photon like a wave - i.e. instead of a bullet being fired at a solid object, imagine a bunch of objects floating around in the ocean being shoved around by a water wave. This is the case for visible light and atoms. Visible light is 100s of nanometres in wavelength, but atoms can be even smaller than 1 nanometre. So you can't really "miss" with visible light - the photon passes through hundreds of atoms at the same time. This means there is definitely some interaction going on, and so the photon can be changed a little by the atoms, and that allows you to "see" the atoms when the photon hits your eye.


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

[User]
[Back to the Future] How did Doc meet Clara?

Based on Doc's gravestone in BTTF3, it's assumed he was close to Clara as the grave reads "his beloved Clara" which evokes confusion in Marty and Doc. Before Marty goes back to warn Doc, Clara is supposed to die falling into what is later known as Clayton Ravine, so named as a teacher named Clara Clayton fell in there.

Doc and (to a lesser extent) Marty save Clara which results in a big moral conundrum for Doc as he has changed history again. Regardless, the new events have led to the ravine being named Shonash Ravine. If we assume there are 3 timelines based around 1885, A) The original without Doc or any BTTF interference, B) the one with Doc sent back without Marty and ends up dying by Buford's gun but *after* he met Clara, and C) basically the entirety of BTTF3 where Marty saves Doc, surely either Marty wouldn't know of Clayton Ravine due to Doc already having saved her, OR Doc couldn't have known Clara?

[Assistant] When Doc and Marty are talking, the Mayor of Hill Valley drops Doc's place by to remind Doc that he's supposed to meet the new schoolteacher the following morning, telling them her name. In the timeline without Marty, Doc went on to do just that and met Clara, escorting her into town safely.


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

[User] Would Koko, the sign-language speaking gorilla, have been able to translate what a different, non-signing gorilla was saying?

[Assistant] Define 'saying'. Koko may be able to sign that another gorilla is angry, but gorilla interpersonal communication consists mainly of body language, and getting a *gorilla* to interpret that for a *human* is probably a hundred times more difficult than to just ask a human to interpret it.


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

[User]
[One Punch Man] Has Saitama updated his workout routine?

>100 Push-ups!

>100 Sit-ups!

>100 Squats!

>10k run!

Does this workout do anything for the strongest man in the world anymore? They pretty much all involve using your own weight for resistance, and Saitama obviously has no problems with weight far beyond his own.

[Assistant]
I think he still does it. As he mentioned, it's critical that you do the workout every single day, no matter what.

I also don't think he'd allow himself to become weaker. His goal is to try his best and find worthy opponents at that level. Knowing he could do better would be unsatisfying to him.


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

[User]
ELI5: Why the British resent Margaret Thatcher.

I've heard that many people blame Thatcher for some of the problems the country has today but what did she do? As an American, all I know is that she did something to take away serving milk in schools so people called her "Milk Snatcher Thatcher."

[Assistant]
In the 1980's the British economy was struggling. To get the country out of the mess it was in, she decided to deregulate the banks, sell government owned companies, and get rid of "out-dated" forms of industry, and manufacturing eg: coal mining.

This made a lot of people, mainly public sector workers and "blue collar" workers, lose their jobs. The coal miners especially were upset and striked for a long time, however this didn't do any good and in the end they still lost their jobs and livelihoods. This also decimated towns that were built near the mines, turning them into ghost towns filled with unemployed.

It also ushered in the era of the UK being a finance based economy, as opposed to manufacturing, which although made some people very rich in the short term did not provide a long term solution to the UK's problems. It can be argued that the current problems in the UK economy are directly due to the changes she instigated, and which the following prime ministers didn't, and couldn't/wouldn't change.

So that in a nutshell is why a lot of people really hate her.

EDIT: Took out inaccurate info about Falklands war.


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

[User]
ELI5 why is bacon so different from the rest of the pig?

It tastes nothing like pork chops, what gives?

[Assistant] Bacon is cured and often smoked. The curing and smoking process dramatically alters the flavour of the meat. If you smoked and cured a pork chop it would taste a lot like bacon (though it has less fat so it would be dry and tough, which is why we don't do this to chops or leaner cuts of meat).


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

[User] ELI5:If the counterfeiter is talented enough to make a $100 bill that looks and feels like real money to a cashier, why aren't they talented enough to make it react the same way to the pen they use to test it as real money does? Is that pen truly a foolproof way to tell if a bill is real or fake?

[Assistant] The pen in not 100% effective. The reason we have multiple means of verification like the strip, the pen, and the watermark to make counterfeit bills harder to produce. I've had 5's washed out and printed over with a 100 that passed the pen but failed the watermark. Its possible to make very good fake bills but very hard to make perfect ones.