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

[User]
ELI5 why babies are born all messed up when a a brother has sex with a sister? Like an inbred child?

I just saw a post that had a picture of a pretty fucked up baby and it said "this is what happens when you knock up your sister"

Well I never really knew why that happens, can someone explain? I remember hearing how it's because of certain genes.

[Assistant]
What you're talking about is "deadly recessive" genes.

Sexual reproduction (rather than asexual reproduction, where a creature does not need a mate to create an offspring) has one big advantage: it combines the DNA of two different creatures.

So let's say there's a recessive gene in your DNA.  It's not a good gene, it'll mess up your heart, or cause brain development issues.  Fortunately, tho' you have this gene, it is recessive, and you also have a perfectly functional gene which is dominant.  So the bad gene does no harm to you.

Now, your sister also has these same two genes.  No big deal for her either.

But if you two both produced a child, that child will inherit one gene from each of you.  If the child inherits the bad gene from you both, then it doesn't get the good dominant gene to overwrite the issue, and ends up with the brain development issues or the malformed heart etc.

Now, there's a chance of picking up a bad gene in any kid.  But the chances of getting two copies of the same bad gene is considerably greater when both parents have it.  And in the case of siblings, they're much more likely to share the same genes.

Make sense?


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

[User] Why are hydrogels used in tissue engineering, what is the main advantage over just sterile water?

[Assistant]
Some context would be helpful, as this is a vast field. Some important aspects:

- Hydrogels have a shear modulus and don't drip away, in contrast to water.

- Hydrogels can have a stiffness and viscoelasticity that's tunable in situ, unlike water.

- Hydrogels may contain electrolytes to maintain isotonicity with physiological fluids; pure water isn't isotonic.

- Hydrogels can hold useful cells (e.g., stem cells) in position in the manner of a scaffold; water can't.

- Hydrogels can be fabricated to present tissue-like mechanical properties that drive cells toward certain behavior; water doesn't provide this.


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

[User]
ELI5 why does the same temperature feel warmer outdoors than indoors?

During summers, 60 F feels ok while 70 F is warm when you are outside. However, 70 F is very comfortable indoors while 60 F is uncomfortably cold. Why does it matter if the temperature we are talking about is indoors or outdoors?

[Assistant] The sun provides (at peak) about 1300 Watts of heat per square meter of area.  So, even in the winter when the sun is lower (therefore the angle  of incidence is lower, and less heat will be absorbed) you could still be getting a few hundred Watts of heat just by being in the sun.  Quite honestly, 60 F (15C) and direct sun is usually uncomfortably warm for me.  Go stand in front of a 1000 W electric heater and see!  The amount of sunlight is often more important in determining comfort than the air temperature.


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

[User]
ELI5: Why does "rapid rehydration kill"?

I am reading a book about the nuclear bombs thrown on Hiroshima and Nagasaki. During the blast, the heat skyrocketed and this caused survivors to lose most of the water in their bodies. As a result, they felt extremely thirsty yet they would die when they drank.

Did they die because they drank? The book says "rapid rehydration kills" but I don't understand why this would be so. I would understand better if it was said they could not drink fast enough but then surely they wouldn't even make it to the watering holes/rivers/water tanks?

So: why would rapid rehydration kill a dehydrated person?

E: For the record, the book I am reading is "Hiroshima Nagasaki" by Paul Ham.

[Assistant]
Alright, think of it this way.

Your cells are little sacs containing a bunch of solutes, like sodium and electrolytes. When the water-solute balance in your body is off (because you've drunk more water than your body can handle), the cells attempt to compensate by absorbing water from outside the cell (osmosis). The cells figure, *"It's OK! We have enough salts and electrolytes that we can take on a little extra water!"*

...but if the imbalance is great enough, the cells can't absorb enough water to correct it. All that extra water causes the cells to swell. When the brain cells swell this can interfere with their ability to function or cut off blood flow, resulting in death.


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

[User]
Could a planet orbit the sun on a vertical plane as opposed to the horizontal plane of the other planets?

I am not sure of terminology, but assuming that all the planets are on the same horizontal plane could another planet orbit on a vertical plane?

[Assistant]
Bet of a mess here so I'll make a bit of a tl;dr top-level response:

1. Planets form in a flat plane because they all form from a disc of gas.

2. But if you somehow got a planet in vertical orbit *after* the gas disc had dissipated, it should continue quite happily, and there are indeed small objects in the solar system that do have very very high inclinations in their orbits.


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

[User]
ELI5 What level of play can be expected from a Chess Grandmaster?

I know they're super good at chess.  But can someone explain the type of thinking or styles of play that might come from a grand master (and you wouldn't see in players that aren't quite as good)?

[Assistant]
The difference between a good player and a grandmaster is the difference between tactics and strategy.

Games between good players are generally decided by tactics.  Some common tactics are forks (attacking two pieces at once), discovered attacks (moving a piece so the piece behind it can attack), and pins (holding an enemy piece in place).  Generally, they're moves that give good short-term results.

When grandmasters play, it comes down to strategy.  Yes, the tactics still matter, but both sides know them all very well.  Instead, it's about the long game.  There's a lot of focus on control of rows, columns, and diagonals.  You also tend to see lots of moves that don't serve any immediate purpose, but which set up combinations of strong moves that lead into each other.  When that works right, you see games go from evenly balanced to overwhelmingly one-sided in a very short time frame.


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

[User]
After death how long do processes like digestion or cell regeneration continue to go on and what ultimately stops them?

I would imagine that the processes don't stop immediately.

[Assistant]
In short, what ultimately stops cell processes after death is lack of oxygen. Without oxygen ions to fix electrons on the cellular level, cells are unable to function or reproduce, and they begin to decay.

For some cells that require constant oxygen (such as neurons) this can happen almost immediately (within minutes) after death. For other cells that are not quite as oxygen thirsty (such as in the transplant organs) this can take between 30 or 60 minutes. Structural cells which require even less oxygen, such as in bone and connective tissue, can survive for around 24 hours after death before cell death occurs.


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

[User] ELI5. When hooved animal's hooves are left untreated they over grow and become unhealthy. Does this happen in the wild?

[Assistant]
Unlikely. A hooved animal in the wild gets to run around on dirt, rock and gravel, so that naturally wears down the hoof. A bit like how if your dog is outside a lot, you don't have to clip its nails nearly as much as an inside-only pet, because its claws get worn down by the patio, sidewalk, gravel etc.

Those rescue ponies and horses with the super gross curled up hooves, those are because those poor beasties have never been walked on anything but a stall or soft arena dirt, so there's been nothing to wear them down naturally. The sad thing is that can really screw up their feet; even after the ferrier corrects their hooves they're not gonna be walking normally for long time.


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

[User] [Star Trek] How do Borg assimilate non-humaniod species and other species which needs very special living conditions into the Hive?

[Assistant]
Borg drones can apparently survive in highly inhospitable conditions. In First Contact, we see human Borg drones operate on the outside of the Enterprise without apparent extra equipment. So the cybernetic augmentation can probably keep most drones functional in the same environment.

Otherwise, they might assimilate them by planet where those living conditions are met. If they can benefit the Collective without ever stepping on a vessel, then why not assimilate them? Or if they are beneficial on Borg vessels, then there might be specialised areas for them.
After all, Federation vessels apparently also had quarters for non-humanoid crew members. While never shown, it's occasionally mentioned how the Enterprise in Next Generation has a few whales and dolphins as crew members.

The Borg might have similar areas on their vessels, planets and structures.

Else, if a species is  more trouble than it's worth, they'd probably just ignore them.


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

[User]
ELI5: What is the psychological reason why people who are close affectionately poke fun at each other?

Why does my best friend and I greeting each other with "what's up you fuckin' slut" draw us closer? By all accounts it doesn't make sense.

[Assistant] Aggression is playfully used right across the animal kingdom, so it is probably an inherited way of forming a relationship - some tropical fish (ciclids) fight through mouth-wrestling, and when a male and female are evenly matched, instead of the weaker fleeing from the stronger, they become mates for life and proceed to lay egss and raise a family.


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

[User]
[Attack on titan] Could barbed wire work against titans?

Seems like it could be a cheap and safe way to slow and bring down titans, specially the smaller ones.

Maybe the wire would have be stronger than the one intended to stop humans.

[Assistant]
Could be quite a good tactic, but you have to remember Titans are often quite bulky and big monsters that blunder headfirst towards their targets.

You'd likely need multiple rows of barbed wire reinforced several times and secured *strongly* to prevent the first 6m Titan from simply stumbling into it, getting wrapped up and pulling it out of its fixtures.

Interestingly enough (given where the series goes) I'd actually think some sort of WWI style trench warfare might work better against Titans. Tons of barbed wire (scaled to work against Titans) and trenches thin and deep enough to allow humans to quickly and safely navigate the battlefield while Titans are impeded by the barbed wire and unable to effectively reach in and grab their targets. From bunkers behind the trenches they can fire cannons and other ranged weapons across no man's land to mow down Titans. Any crippled Titans are finished off when the humans conduct a sweep of no man's land for injured humans and surviving Titans.

This all goes to pot when you involve a special Titan-shifter. It's still way more effective than early AoT open field Titan combat (given the trenches for cover, barbed wire to slow or direct the approach and bunkers for sustained fire), but is certainly only a delay for an intelligent Titan-shifter to avoid.


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

[User]
CMV: I feel it's my responsibility to report cheating/infidelity to the wronged party in most every circumstance, because if I was being cheated on I would want people I know to do the same for me. Change my view.

My opinion stems from an idea that I've encountered a long time ago, being that "If your partner was cheating on you, wouldn't you want to know?" I feel like most people would want to be aware of a partner's infidelity rather than not, because it empowers them to act on the situation. Being in the dark leaves them totally powerless.

 Beyond just the cheating aspect to it, there's also the issue of health and safety. Everyone has a right to controlling their own sexual health, and undisclosed infidelity removes that right from people without their knowledge. In addition, cheating can be an excellent indicator of a relationship that needs to be ended, or a kick in the pants if you will. ;D And while it totally is more ideal for the cheating partner themselves to be the bearer of the bad news, many people don't for numerous reasons. (Some of those reasons being reasonable for sure.) As an addendum to all this, it's also my opinion that cheating isn't always a relationship ending event. There's always room to work in that situation.

I've been been seeing and hearing a lot recently a number of people expressing the opposite idea of mine, namely non-intervention, which surprised me greatly! Dan Savage is one particular, his view stemming primarily from a place of "It's not your relationship, you shouldn't go mucking about in it." Which I get, but it doesn't seem compelling in the light of wanting to be there to support people that I know and love. I know that if a significant other of mine were to cheat on me the response of someone that had specific knowledge of it being "I didn't think I should get involved" wouldn't be terribly comforting in light of the abandonment that can be associated with infidelity. Am I missing something here?

I mean, I'd certainly only taddle on someone if I have really solid evidence, like specific messages or solid first hand evidence, and only in cases of actual egregious action. (So not for instance if they're flirting or being unusually snuggly.) And certainly only if I know that they aren't poly/have an open relationship. And there's absolutely room for flexibility. By no means am I saying that I have no other recourse than to report cheating, especially if it's it's a relationship I'm close to. All this to say that I'm not foolish, And would do my best to take the action that's best for both people involved, regardless of who is cheating.

**TL;DR**: I feel that it's almost always my duty to report cheating to the "cheated on" in a relationship, as long as I have good evidence/reasons for doing so. A non-intervention attitude seems unhelpful and potentially hurtful to those being wronged, in addition to health related reasons.

So please change my view! I'm very interested in hearing alternate viewpoints here, both because it's so clearly opposed to my own view and I was very surprised at the number of people out there that disagreed with me. Thanks CMV!

**Small Update:**After reading through these generally great replies, I've been given a lot to think about. I was planning on taking this talk to other people in my life that'd have good opinions to share about this topic, but now I'm reconsidering pending some reconsideration. While I wouldn't say my view has definitively changed, I'm glad to have been give a lot of really solid counterpoints to what I believe. Thanks so much CMV!

[Assistant]
First, you're making an assumption that sexual encounters outside the relationship are cheating.  Some people have open relationships.  Some people with open relationships keep quiet about it to their friends and family because *it's none of their business*.

Second, and more importantly, you are not privy to their internal relationship dynamics.  Maybe the cheated on party knows about it, but is deciding to keep quiet for one reason or another.  By telling the cheated on party, you make it clear that people outside the relationship know, which could cause significant added stress.


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

[User]
How does eye color change?

I know that some people have eye colors that change noticeably and that children may have blue eyes that change color as they get older. How/why does this happen?

Edit: Also please answer kwagener's potential color changes "Mine go from dark brown to bright green depending on the mood I'm in"

[Assistant]
It's not that the amount, or color of, pigment in the iris changes, but as the iris dilates and contracts, the pigment becomes concentrated or spread out, changing the perceived color. There are also differences in perceived color depending on the type and intensity of the light source.

As for babies, some are born without the pigment fully developed, and it takes time for it to come in.


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

[User] [Star Wars] Why does Kylo Ren wear a mask?

[Assistant]
A mask in that style seems to be a standard part of the uniform of the Knights of Ren, which is the Sith group that Kylo Ren is formally a part of, and operates on the orders of Snoke, alongside the First Order.

As a bonus, Kylo/Ben is trying really hard to emulate Darth Vader, so a mask is pretty essential piece of wardrobe for his tribute cosplay.


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

[User]
How does a hot object like metal or magma produce light?

From my understanding, something has to be changing chemically to produce light, but a glowing hot steel rod or magma produce light by just being physically hot. How does his work?

[Assistant]
This effect is called blackbody radiation. One aspect of temperature is the random vibration of atoms. Sometimes this vibration results in an electron in the atom being bumped to a higher energy state, which also slightly cools the atom. When the electron falls back down to a lower energy state, it emits light at a specific wavelength depending on where it fell from and to. Wavelength determines energy and color.

The highest energy light that room temperature objects emit is infrared, or more red than red. The cells in your eyes are not able to detect this or any lower wavelength of light. As the temperature of an object increases, both the total amount of light and the maximum wavelength increase, and around 750K or 480 degrees C, visible red light is emitted. As the temperature increases further, light in the green and eventually blue is emitted. This is why a Tungsten light-bulb at 3000K looks white, all visible wavelengths are being emitted.


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

[User] ELI5: Where does the brain generate its current to send small electrical impulses to muscles etc...?

[Assistant]
There are pumps and gates in your cell membranes, which control the flow of ions. Ions are charged particles (positive or negative), so their movement creates a current and thus electrical impulses.

One example of a pump is the sodium-potassium pump. This pump exchanges 3 Na+ (soidum) ions for 2 K+ (potassium) ions, making the cell lose 1 positive ion each time. This makes the cell more and more negatively charged over time. This effect is slow-ish and mostly constant.

Now we come to the gates. These have a threshold, like a plug in a broken dam holding back the water. Once the threshold limit is crossed, everything just bursts through.

In the sodium-potassium example, the sodium gate will open when the cell reaches a certain threshold of negative charge, which will instantly draw the sodium from outside the cell back into the cell to balance the concentration lost by the pump. This causes a massive shift of ions, creating an electrical impulse.

The electrical impulse can also trigger other gates in neighbouring cells to open, causing a cascade where the first signal spreads out and travels down the nerves to muscle cells.


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

[User] Why does some spicy food have a delay, whereas with others the heat can be felt immediately?

[Assistant]
Depends on the fat content and oils, aswell as what the rest of the dish consists of and also the fruit itself. Fats and oils can coat your tongue and be a sort of shield. Capsaicin doesnt dissolve well in water, but there are proteins that break it down. Milk for example has proteins that can break down capsaicin, and it has fats. This is why dairy helps and water doesn't when needing to cool down your mouth from spicy food. This is why you want to flush it down with something that also breaks it down, because if you you water for example, you're not really doing much other than spreading it around, where it will continue to linger until the enzymes in your saliva as broken them down or you have eaten enough other food to have taken some of it down with it.
 So in short to your question, water content, oil and fat content, what you have previously eaten, what you choose to eat/drink after, the types of enzymes in what you're eating and your saliva. If you already have oil in your mouth from something else, the spice might feel delayed because of it working as a protective shield. If you're... goin in dry so to speak, you're more likely to feel the spice much more quickly.


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

[User]
ELI5:What is it that makes Toyotas so reliable even after many years of use?

Large amounts of spare parts made? Manufacturing process? Design differences?

[Assistant] Toyota revolutionized a manufacturing process about 40 years ago that allowed bottom up refinements to address manufacturing issues (the assembly guys on the line can spot an issue and report it up the hierarchy to get it changed, rather than waiting for the managers and engineers to discover issue) and had an extreme focus on quality. At this point, other car makers have caught up in many respects and its more reputation than anything at this point. And the worst brands today are still better than the best a generation ago in terms of reliability.


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

[User] ELI5: Why do some sporting events start at such random times, for example Duke vs. Wisconsin started at 9:18, why not 9:00 or 9:30?

[Assistant] This is to give the pre show broadcasting team to have time to set up and introduce the game. Additionally, this is a marketing scheme for organizers to earn more money as you tune in at 9:00 PM with a bucket of pop corn and watch 18 minutes of advertisements.


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

[User]
Why can't objects be seen if they are smaller than the wavelength you are using?

Is there a physical visualization that can help reinforce this? I'm not seeing the relationship between the wavelength and physical object size.

The wavelength of light is continuous, and describes the E/M vector at a point. So if we have an atom at some position X, and we shoot an infinitely thin beam of visible light (wavelength larger than atom's size), the light must travel and hit the atom at position X because the light is continuous. It's not like the lightwave just skips over position X. So the atom should interact with the visible light, somehow. If it were to reflect the visible light back to us, then why can't we see the atom?

[Assistant]
If you want a really far but easy way to see it, try to find where a grape ( in reality a bacteria) is on a table using a toothpick (electrons), a carrot (visible light), an apple (infrared) and a watermelon (radio).

As long a the wavelength (diameter) of the tool is smaller than the object you want to resolve, you have no problem defining where the object is and even details of the contour ( that is the toothpick).

When the wavelength of the tool is comparable you can still see that something of that approximate size is there (that is the carrot).

When the wavelength is larger, best case you may see some faint scattering that tells you there is something different about the area where the grape is (with an apple), and at a certain point it is unlikely you see anything at all (watermelon).


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

[User] ELI5: When you have an itch on your back and someone scratches it for you, why does it then travel to other parts of your back?

[Assistant]
Scientists have known for decades that scratching creates a mild amount of pain in the skin.

Scientists worked out that scratching causes a sensation of pain. This causes the brain to release serotonin is to control the pain. But serotonin activates itch-transmitting cells, making the itch worse

In humans, it is not possible to block serotonin to control itching as it is important for pain-control

Senior investigator Doctor Zhou-Feng Chen, director of Washington University's Centre for the Study of Itch, said that pain can interfere with itching - at least temporarily - by getting nerve cells in the spinal cord to carry pain signals to the brain instead of itch signals.

Dr Chen said: 'The problem is that when the brain gets those pain signals, it responds by producing the neurotransmitter serotonin to help control that pain.'

As serotonin spreads from the brain into the spinal cord, the chemical can 'jump the tracks'  moving from neurons that sense pain to nerve cells that influence the intensity of an itch, she added.

EDIT: Explanation to a 5 year old - It's all in the mind.


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

[User]
If your body temperature drops while you sleep, why do you often wake up in sweat?

Are the two related?

[Assistant] The exactly same (opposite) thing happens when you have a fever- Your body raises its temperature to kill bugs that are infecting you, and the sensation is that you have chills.  It might be related to temperature relativity, in that since your body temp becomes a bit lower, the ambient temperature of the room is perceived as a bit warmer than usual.  The two main reasons for sweating are from either your hypothalamus trying to lower body temperature, or a sympathetic response on sweat gland acetylcholine receptors.


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

[User]
[MCU/No Way Home] Question about Aunt May.

During No Way Home, it would be Aunt May who would convince Peter to try to help the villains who had come to their world and save them from their deaths. How do the villains thank her for her hospitality? By trashing their apartment and Green Goblin murdering Aunt May in cold blood. In spite of this, even as she lay dying in Peter's arms, she tells him that it wasn't a mistake to try to help them and that Peter shouldn't give up on them. Why? She's seen first hand how they react to the kind of help they wanted to give, so why does she still want Peter to try to get through to them?

[Assistant]
I imagine it wasn't the first time she has exposed herself to someone in need and seen it backfire on her. She volunteers at a shelter, and takes the time to talk to and care for the people who use the facility. There must've been many people who were dishonest/shifty/looking to take advantage of her good heart. She's learnt to overlook those incidents because there are many more people who need help and who would miss out if she'd gives up.

I guess she lived by a philosophy, a principle, really. She believed that if you could do good things for other people, you had a moral obligation to do those things.

There's probably a more pithy way of saying that ...


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

[User]
[MCU] Did Thanos have plans to help a post-Snap universe prosper?

Sure, he rationalises earlier that Gamora's people have naturally enjoyed a paradise and full bellies, but does he really plan to sit back and retire or is he gonna get stuck in and help the survivors? Perhaps that dream of farming is to help bolster supplies? Or is it just for leisure?

[Assistant]
It's just leisure - his work is done, and the universe is better for it, as far as he's concerned.  The planets that he's halved have always prospered in the past, so he absolutely believes that the universe will prosper on its own, now that he's given it that little nudge in the right direction.

Thanos has devoted his whole life to this one goal and finally seen it through, despite the cost.  He's earned a bit of R&R while the rest of the universe gets through this little speed bump and gets back on track.  The worlds don't need him any more, because he's finally given them what they needed.


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

[User]
Are the theories put forth in "Guns, Germs, and Steel" widely accepted by science?

I'm just curious. Jared Diamond seems to be making a lot of assumptions about the reactions of the minds of centuries old civilizations to technology such as guns, mounted horsemen, etc. I think the theory seems really clean and solid, but I keep wondering if all these little assumptions are true for certain.

[Assistant]
It would be helpful if you could be more specific about what theories or maybe some examples.

Diamond's main thesis is that the course of civilization was influenced by the starting conditions of geography and ecology. The idea that there are more easily domesticated animals in Eurasia and that the east-west orientation of the continent facilitates technology dispersion is generally well accepted. These two facts resulting in all geopolitical history up till now is more contested.

The reactions in the minds seem fairly unimportant for the larger theory. The psychological impact of seeing a mounted rider was probably less important than lacking the knowledge to fight a mounted rider.


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

[User] ELI5: How do you find the line of best fit on a scatterplot?

[Assistant] There are different ways to do it depending on what you care about most.  The most common way is doing a least squares regression.  Basically you use calculus to figure out the line that makes the square of the distance from that line to each point the smallest.   The math of it is a bit above an ELI5 but you can look up least squares.


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

[User]
[Xmen] How does Wolverine's healing factor work?

Has it been explained in the comics? I've just read that it comes from some dimension(s)?

I've read that a person's metabolism is responsible for all the healing processes and most of it. So how does he have so strong healing enough to cure anything and everything?

[Assistant]
Not explicitly, no.  In fact it's been really really inconsistently portrayed over the years.

He once spent a few weeks stuck in the bottom of a boat, he survived by cutting slices of this arm and eating them.  So clearly his healing is powered by something other than his metabolism.


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

[User] ELI5: Why is the atomic mass unit definedas "one-twelfth of the mass of one atom of carbon-12"? Why specifically carbon and not just the mass of one proton?

[Assistant]
Because the "mass of a proton" is not as easy to define as you think.

It turns out that if you take apart a carbon atom or really any atom into a bunch of protons and neutrons, the protons and neutrons will have more mass than the carbon atom itself. This is because free protons/neutrons have more energy than a carbon atom, and by Einstein's E=mc^2 they thus have more mass.

In fact there used to be an older definition of the AMU that used oxygen instead. But oxygen has slightly different binding energy to carbon and as such a slightly different amu, the scientific community came to a consensus that both definitions could not be used.

Regardless though we could have defined the AMU to be the mass of a free proton/neutron. The reason seems to be because carbon is a convenient element. Its solid at room temperature and pressure, pretty chemically stable, and as such experiments could be conducted on things made from carbon pretty easily to determine the count of the carbon atoms in it.


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

[User] eli5 I never wake up at 9am but if I set my alarm for 9am I will wake up a couple of minutes before. how does this happen?

[Assistant] You body has its own internal timekeeping (most creatures do). In particular theres your daily circadian rhythm which involves two 24-hour clocks in your brain (suprachiasmatic nuclei in your hypothalamus). These keep a steady tempo. Just like a watch, they need to be told what your timezone is so that you can wake during the day and sleep during the night (instead of the other way around). So your body responds to information like light, which affects hormones, to tell your timers when daytime is. This means your brain has a way of knowing what time it is. It therefore can subconsciously coordinate with your alarm clock. The process is not sudden, it happens gradually. There accuracy is not 100%, so your body can be a bit early or a bit late. But if you tend to feel anxious or stressed (and if you hate alarms) or if youre a light sleeper and there is environmental information (like birds, sunrise, traffic, etc), the tipping point can happen just before your alarm. It is possible for you to consciously intend to wake at a certain time without the alarm even existing, and your brain will comply. Likewise, if you know it is the weekend, your conscious intent can make your brain let you sleep in. Its not a hard and fast rule for everyone, but the effect is certainly there.


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

[User] [The Walking Dead] What is the state of the rest of the world? The country?

[Assistant]
Small cells of survivors exist all across the world. The United States has collapsed, but many survivors exist in rural america. Some exist in impromptu forts scattered in only the most rural areas of America. The Rocky Mountains, the Nevada desert, the dense marshes of the south and the great forest of the north. The large amounts of firearms that exist in the US have given the survivors a slight fighting chance.

Canada is a barren tundra. Survivors have fled south to escape the harsh Canadian winter. Some survivalist cling to life in the Yukon in small camps, but many have resorted to cannibalism to survive in their remote hideaways.

Survivors exist within Mexico, hiding in the sprawling Mexican deserts. With the government collapsed, the cartels have used their weaponry to create small nations of their own. The savage Mexican gangsters, hardened by years of gang violence, have adapted well to the new world.

Cuba, Haiti, Jamaica, and the Bahamas saw some peace during the early outbreak. This didn't last, as refugees from Florida and Latin America have overwhelmed their shores. This population boom has led to incredibly chaotic outbreaks throughout the Carribean. The only survivors have taken to the seas, traveling the Gulf Coast and scavenging the abandoned ports.

Most of the Brazilians have fled deep into the Amazon. Not many of these survivors could make it, and succumbed to disease and predators. These deaths have led to the Amazon being littered with the undead, lying in wait within the brush. The Brazilians rarely leave their fortified jungle camps for fear of being ambushed. Their settlements, though, are by far the most prosperous in the Americas. Fertile soil has led to an abundance of food for the survivors.

The southernmost people of South America have mostly retreated into the Andes. Many reside in the Incan ruins, repairing the ancient terrace farms to provide food as well as protection from the occasional walker.

The people of the British Isles have regressed to a way of life they haven't known for centuries. Fleeing into the long abandoned medieval ruins, the British have reentered an age of castles and siege warfare in their struggle against the walkers. Antique swords, sabres, pikes, and crossbows have now become the norm for survivors, who have utilized these weapons to dispatch walkers with ease.

Most of mainland Europe has fled into the Appalachian mountains, the forest of Germany, or the mountains of Greece. The catacombs of Paris and Rome now teem with walkers, so many that clearing them all is impossible. Should humanity bounce back, these historic cities are lost to man forever.

India and China, the two most populous nations on Earth, are the most devastated. Roughly a thousand Indians and Chinese have survived the largest outbreak on the planet by fleeing into the ocean.

Russia's evacuation of the Oblast beyond the Ural mountains has backfired. Siberia is largely infested by Chinese and Central Asian walkers, but many military and civilian settlements still scrape out a living. Compared to the rest of the world, Russia is one of the only nations with an intact military (despite the lack of a nation to fight for).

The Middle East, a region previously plagued by warfare and unrest, had been pushed over the breaking point by the walkers. The nuclear exchange between the Middle Easterners has reduced entire nations into radioactive wastelands owned only by the dead. Some refugees from the Levant managed to escape to Cyprus, where Jews and Muslims maintain an uneasy alliance for survivals sake.

The state of Africa is unknown, as many of the more populous cities have been reduced to nothing but walker nest. It's possible that some militias still survive deeper within the continent, but we cannot be certain.

All in all, no nation still truly stands on Earth. Though many governments still survive within bunkers or isolated military bases, humanity is now nothing more than scattered plots of survivors dotting the world.


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

[User] ELI5: My mom has always told me to wash my hands after touching money because "there is a a load of bacteria on them from countless people touching them before". Is there any truth in it?

[Assistant]
Yes,  there's a load of bacteria on money.

However,  there's a load of bacteria on pretty much everything.

You don't need to wash your hands after touching everything - just avoid touching your mouth, nose, or eyes too much.


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

[User] ELI5: What happens to sound after the sound is no longer there, it seems to vanish, but where do sounds go?

[Assistant]
Sounds are waves in air. They will slowly disperse and turn into heat after hitting things and being partially reflected and spread out over a wide area.

Imagine dropping a stone into a pond, just like the waterwaves soundwaves will get weaker quickly.


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

[User]
[Jurassic Park] Is there any interest in cloning prehistoric mammals in this world? What about Neanderthals and Australopithecus?

Like the Wooly Mammoth, the Smilodon, the Andrewsarchus, the Paraceratherium, the Embolotherium, the Hyaenodon, etc.

What about Neanderthals and Australopithecus?

[Assistant]
It's considered to have low scientific value.  The changes are significant enough to create problems, IE the staff of the Jurrasic World park understood that the reconstructed clones varied greatly in appearance from the originals, and even if they patched those up they'd lack the original symbiotic bacteria, the learned behaviors that some real dinosaurs picked up from parents, and the ability to compare behavior in captivity from behavior in the wild, which is sometimes wildly different. Even the very large ranges that were eventually built are small enough to cause island effects, which would distort both behavior and biology.

Economically it's a very expensive undertaking with a necessarily expensive ticket price (no matter how cheap you set the ticket price, you gotta build it on a remote island to limit invasive species events, which means customers have to pay somebody else a bunch of money for a plane ticket), so unless demand is very very high the numbers don't work out. Dinosaurs are much sexier than mammoths etc, though you could maybe talk the existing park into opening a mammalian megafauna wing if it actually reopens.

As far as other species of human go that opens up a massive ethical clusterfuck, while cloned mostly-dinosaurs isn't really any dicier than zoos in general (hell its better really, you don't have to take any out of the wild to begin with).


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

[User] Do insects get sick? like do ants get colds or do bees get STI's?

[Assistant]
yes. getting sick means you get infected by bacteria or virii or parasites or ... and of course, this can happen to insects, too. however, they have a different response than humans (read mammals) do. you e.g. have increased temperature to support your immuno cells to fight the intruders. this inflammatory response (which includes many more actions) cannot happen in insects as they don't have this superb system. however, they still have basic immunity granted by a basic system.

edit: got told it is viruses, not virii.


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

[User]
ELI5: How do nurses, drug users, etc inject a drug directly into a vein? How do they know the needle tip hasn't gone through the vein or even missed it completely?

I'd imagine most veins are less than 5mm in diameter, that's a pretty small target to land the tip of the needle in. How do they do it?

[Assistant] The "flash". Before pushing in, you draw back on the plunger. If the needle or catheter is in a vein, blood will easily be drawn back into the tubing or syringe and then you can push the medication or fluid in once you see that. If you're not in a vein, you won't easily pull blood out when drawing back.


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

[User] ELI5: why , when someone is badly burnt do they die? What causes the body to say ok this is too much- while extremely painful- what's actually causing death in this or similar situations??

[Assistant]
Burns are extremely good at inflicting lasting trauma that people can't recover from. Basically, there are two reasons:

1. Burns take away skin, which is your most important defense against infection. A third degree burn over any significant percentage of the body will leave you open to massive systemic infection.

2. Really severe burns also burden your kidneys (and possibly your liver, but don't quote me on this) with what amounts to a bunch of charred flesh in the bloodstream. This can screw up your kidneys to the point that it kills you, all by itself, but even if it doesn't finish you off, it can present a giant problem: if a patient's kidneys are barely functioning, you can't give them most pain drugs, as well as anything else that puts stress on the kidneys.


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

[User]
Why does majority of software need to be installed?

Is it because of fear of piracy or maybe the software needs to be decompressed?

[Assistant]
It would certainly work to tell the user to download lots of files and have them put them in a specific directories, but it would be a pain. So having a single file to download is nice. This is some sort of archive format. It makes sense to compress it since download speeds are slower than having the CPU run the decompression. Adding an installer let's the software do some additional integration, like adding icons, putting configuration settings in a standard place. Letting the software be started as a service/daemon using standard tools, putting the main executable in your path, have it open certain file types by default.

Tldr: convenience.


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

[User]
[The Matrix] How did Cypher get in contact with Agent Smith to arrange a meeting?.

This isn't a question about how Cypher got into The Matrix because that has been asked and answered several times before.

Rather the question is how he managed to contact Smith and arrange the dinner with him?.

Did he just jack himself into the matrix and simply waited for an agent to arrive and say "Hey I want to betray the rebels" ?

Did he have to get their attention by doing "impossible" things that would threaten the system?.

Or maybe was he somehow communicating his intent to the agents before the meeting?

[Assistant] I just rewatched this and never noticed this before - there's a scene right after Neo leaves the Matrix, where he walks up behind Cypher and Cypher turns and sees him and is super startled! Then theu talk about how the Matrix code is too complicated to visualize on the moniters like the training room, but after awhile you don't even see it anymore. Then he shares the hooch with him. So basically presumably Neo walked in on Cypher contacting the agents, then Cypher confirmed that Neo cannot actually read that code still.


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

[User] ELI5: The 11th amendment to the US constitution.

[Assistant]
The 11th Amendment is fundamentally about the legal doctrine of sovereign immunity, which says that a sovereign state can't be held accountable in a court of law unless it consents to be, since it's the source of the law in the first place.

Originally, US states were effectively separate countries, so they had sovereign immunity.  After the US Constitution was ratified, the Supreme Court ruled that a particular clause in the Constitution (which said that citizens of one state could sue another state in the Supreme Court) had eliminated the sovereign immunity of the states in those suits.  The 11th Amendment was passed to reverse that and clarify that the states were still immune to suit in those cases.


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

[User]
Eli5 The sun converts about 4 million metric tons of its mass into energy every second. Does this mean that it's mass reduces significantly over the span of, say, ten years?

4 million tons a second is a lot of mass to be lost given enough time.  Considering the fact that the sun is over four billion years old, does this mean that the sun was physically bigger when it formed?

What about a couple of hundred years ago? Or a few years ago? Could the suns loss of mass imply that it's shrinking over time?

[Assistant]
What is "significant" when talking about the reducing mass of the sun? On one hand 4 million tons a second seems significant to us, but the sun is really massive.

Over the course of a year it loses 174 trillion tons of mass. But over the next 5 billion years it will lose 0.034% of its total mass. So yes, it is technically becoming less massive over time, but not to any amount significant to its scale.


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

[User]
ELI5: How does computer memory work?

When you physically save a file, like a photo or a word document, how is it physically saved? Where is that document physically? I believe there are two modern memory devices, HDD and SDD, but how do they work? How can a Hard Disk Drive be scratched the right way to save my essays? And when I save a file to a flash drive, where on the flash drive are my documents? How can another computer read that flash drive? Is it a series of electrons or switches moved to remember each part of the document, like the 38th word on the 4th page?

[Assistant]
What you're talking about is called disk or storage. Memory is a different part of the computer, also called RAM.

With a traditional disk drive (HDD \ Hard Disk Drive) there is a spinning metal disk that is given magnetic charges that represent ones and zeros. Those ones and zeroes can then be read back as data. The charges are wrapped around the disk in a spiral, as if you took a credit card magstripe and layed it along a vinyl record. HDD's can increase storage space by having multiple spinning disks (platters).

Modern SSD (Solid State Drive) storage use the same technology as a USB flash drive, Non-Volatile NAND flash memory. Simply explained, there are large numbers of tiny no-moving-part electronic switches made from transistors, each switch representing a one or a zero, and the switches being organized such that they can be represented as a linear series of ones and zeroes, just like an HDD.

When you save a file onto a drive, the computer saves the ones and zeroes into a spot with enough room to fit the ones and zeroes, then adds that spot to a table of contents at the start of the drive.

Another computer can read the files off of the drive by looking at the table of contents to find where different files begin and end.


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

[User]
[Venom] What happens to the host of a Symbiote when it appears around the host's body?

I was watching the Venom trailer and it shows Venom forming around Eddie (I think that's his name) . Is Eddie still conscious in there? Does he essentially become trapped? Is he able to understand what's going on outside of Venom?

[Assistant]
When symbiote merges with the host, it basically both covers the body and suffuses it, including the brain. That's why host can hear symbiote voice in their head all the time, and that's why symbiote hosts can do freaky stuff like stretching and twisting their bodies in inhuman ways - symbiote largely acts as a buffer and healing medium. For the most part hosts are conscious, but depending on the symbiote they are either trapped and controlled by the creature, or working together with it, forming a single identity like Venom or Carnage.

When it comes to the movie, it seems that that version of Eddie Brock is fighting Venom for control for the most part until the end - which wasn't the case for comic version, where Brock gleefully accepted the symbiote and was the one to call themselves Venom to exact their revenge.


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

[User]
[Family Guy/American Dad] Who's the worse father: Peter Griffin or Stan Smith?

Neither of them are particularly "good" fathers, but compositely(as in throughout all seasons of their respective shows), who is a worse father?

[Assistant]
Id say Peter is worse. Stan might be bad at times, but at least he isnt as openly and maliciously abusive like Peter is to Meg. We do get some moments of questionable behavior, but even those tend to come out of a misguided desire to help in some manner,
I.e, bullying Steve to toughen him up, or trying to manipulate haley towards a perceived successful lifestyle.


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

[User] [Doctor Who] Why did the doctor de age and basically become space Jesus when everyone in the world said his name at the same time?

[Assistant]
Because the Archangel Network, a ton of extraterrestrial Time Lord satellites The Master constructed, were merged with the minds of every human on the planet. All of them directing their networked minds toward one person allowed him to use the combined psychic ability of *billions* of people.

Psychics and psychic abilities, latent or otherwise, are canon in the whoniverse, and a good hundred people who aren't outwardly psychic have the abilities of one together. So multiply that by how *many* hundreds of people he's actually harnessing, and it makes sense that he can easily reshape flesh and use telekinesis.


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

[User] ELI5: How can both fission and fusion release energy if they are opposites of each other?

[Assistant]
Because in fission you're splitting large, complicated atoms that are held together loosely but release extra energy when split;

In fusion you're forcing together two small, light atoms which release energy when you join them.

If you try the reverse -- fusion with large atoms or fission with small atoms -- you don't get extra energy out, you lose a lot of the energy you put into it.

The middle point is iron:  it doesn't do fusion or fission in either direction very well, which is why stars end up with a lot of iron at their core when they die.


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

[User] Why does any length shorter than a Planck make "no physical sense"? Why can't there be half a Planck?

[Assistant] There is no reason to believe the Planck length is in some sense the "smallest possible distance". It's just (1) the length you can construct from fundamental constants and (2) representative of the *scale* at which both quantum and relativistic effects ought to apply.


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

[User]
ELI5: What does 100% air humidity mean?

So I know that atmospheric air has a little bit of H2O in the atmosphere, which I assume is what air humidity is - the amount of H2O is in the atmosphere. However why is there a "100% air humidity"? Is there just a cap on how much water can be in air? And what happens if you add more water?

And is 0% air humidity literally just 0 water particles in the air?

[Assistant] 100 % air humidity means that there is as much water vapor in the atmosphere as possible. If you add more, it will start to condensate into raindrops. 100 % humidity does not mean that 100 % of the air is water vapor. How much water there may be in the atmosphere varies with temperature and what other stuff there is in the atmosphere. A really hot atmosphere may contain a lot more water before it reaches 100 % humidity, which is why the air may feel really damp in the tropics for example. If it is really cold outside, like -20 celsius or colder, the air is really really dry, which also causes dry lips for many.


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

[User]
Can stomach acid burn organs?

Since stomach acid is strong enough to dissolve metal, what would happen if the acid from inside your stomach got out? Would it do the same to other organs?

[Assistant]
Normally, the cells in the lining of the stomach secrete a mucus that protects the stomach from damage from gastric acid. When your body moves your stomach contents (which contains substantial amounts of stomach acid) into your small intestine, your body pretty much immediately neutralizes it with alkaline secretions from the pancreas (EDIT: also from the gall bladder, as bile is also alkaline), because the intestines dont have the same protective capacity as the cells in the stomach.

Other organs in the body lack this kind of protection/countermeasure system. Aspirational pneumonia is a great example (when gastric acid enters the lungs). Another much more common example is GERD (which results from gastric acid refluxing into the esophagus. And as has been mentioned, ulcers in the stomach and intestine result when these protective measures are compromised.

While the acid content of gastric juices is problematic, its not the only problem. Gastric juice also contains pepsin, which is a major player in the digestion of protein. Essentially, once protective measures are compromised (or if they were never present in the first place) you have damage from the acidity, but also you are literally digesting the proteins in your own tissue.


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

[User]
ELI5: How does knocking a person out work?

Something I've always wondered.  A good strong punch, a pistol whip to the back of the head, karate chops...  How is it all supposed to work physiologically?

[Assistant] Not a doctor, not a scientist, but it's an overload. When trauma occurs to the brain like that, certain things happen. All of your senses more or less are stimulated by the impact to the tissue of the brain. It's like when you get hit in the nose ans see white for a second, when you get dizzy from spinning around...imagine all of these happening at once. it's a protective measure of your brain to "shut off," a bit like tripping a breaker, but it can reset itself.


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

[User]
ELI5 Why when falling, we flail our arms and legs

Why do we flail our arms and legs while in the air falling from a large height?

[Assistant] I've always believed it was an instinctual response in an attempt to regain balance. Your body doesn't know how far it's going to fall it just knows you are falling and wants to get your feet under your center of mass.


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

[User] ELI5: Why do scissors enter 'slide mode' sometimes?

[Assistant]
Low friction, very sharp: sschhhhwip ooh baby

High friction, blunt: sshcklaclacklackack ah fuck

Sharp scissors cut with very little force, so there isn't enough energy built up in the pressure of the blade against the paper to rip very far. This keeps the tear immediately next to the blade, so the blade continues to cut with very little force.

With a blunt blade, there isn't enough force to rip the paper against the blade until the tension is much higher, then once the paper begins to tear it can tear further and probably not in a straight line ahead of the blade. So then the blade is pushing against un-torn edge instead of the cleft of the cut and the problem starts again.

You can increase the chances of the sschhhhwip by sharpening the scissors and by slowly closing the scissors as you push, keeping the cut in front of the blades and applying both of them to reduce the required force to cut the paper.

If you push hard, you're more likely to rip the paper.


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

[User]
ELI5: How can 100% orange juice have calories but something like flavored sparkling water containing fruit juice have no calories?

Even if the amount of fruit juice in the water is small, it's still calories, isn't it?

[Assistant]
There is sugar in an orange so there are calories in an orange.

The sparkling water might have an sweetener that our bodies cannot digest (= 0 calories), or one that does not need very much to achieve the same level of sweetness that sugar does (<5 calories = 0 calories).


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

[User]
Identical twins marrying identical twins

Let's just say we have two sets of identical twins, one set of women and one of men. The two identical women marry the two identical men. What is the likelihood that two children, one from each couple, would be identical without being twins?

[Assistant] Barring mutations and other genetical shenanigans, it's exactly as likely as two siblings born to the same parents being identical, which is to say: very unlikely. The probabililty of obtaining the same chromosomes from each parent is 2^(46).


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

[User]
argument against a priori knowledge

I was reading a paper that says the following:

*"According to one influential argument against the existence of a priori knowledge, there is no a priori knowledge because (i) no belief is immune to revision, and (ii) if there were a priori knowledge, at least some beliefs would be unrevisable."*

Please note I am not a philosopher. I am just interested in topics related to philosophy. I studied law.

Now, I am thinking how can you explain the statement "every mother has a child" or 1+1=2 or "single men are not married" . How are those not unrevisable? Those are things that are accurate dead on their face and require no or minimal independant verification or observation.

Thoughts would be appreciated I would like to learn more about this subject.

[Assistant]
Kant responded to Humes argument for the existence of a priori knowledge by arguing that in addition to matters of fact, which Kant calls analytic a priori ( all bachelors are unmarried)  there are synthetic a priori statements which are derived from the combination of basic concepts; mathematics is synthetic a priori because 12 isnt a concept that is already contained in 7+5

Quine is a modern philosopher who rejects the analytic-synthetic distinction altogether. Quine says that all analytic truths require synonymity with facts in the world. Synonymity requires synthetic propositions, so all analytic truths and be reduced to synthetic truth. This seems to be close the kind of argument against a priori that you presented, that we could could revise our previously held a priori truth because or scientific understanding of the world changes.


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

[User]
Is it true that America does not negotiate with terrorists? Why not?

This was a question my little brother asked me after watching The Dark Night Rises.

[Assistant]
If you give a mouse a cookie, he's going to want a glass of milk.

If you negotiate with terrorists, it feeds the cycle that people can manipulate you by being terrorists.  Hence you get more terrorists.


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

[User] ELI5: If skin doesn't pass the scratch test with steel, how come steel still wears down after a lot of contact with skin (e.g. A door handle)

[Assistant]
Cant scratch is not the same as cant damage.

Every time your skin contacts a piece of steel, its leaving behind oils and moisture.

The oils and moisture can chemically corrode the steel surface ever so slightly, forming iron oxide.

While iron oxide is still harder than your skin, its also weak, porous, and brittle. The next touch or cleaning can wear it off, exposing clean steel that can be corroded and eroded again.

It might only be a few molecular layers at a time but over hundreds of thousands of uses the wear adds up to a noticeable amount.


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

[User]
[Harry Potter] Was there ever a particular reason given for why Voldemort was so terrified of death?

Was there a traumatic incident during his formative years or something? Or was it just a phobia with no clear source?

[Assistant]
It's not so much that he was terrified of death, but more that he felt he was above petty mortal limitations.

This included the rules around what magic was considered acceptable, all the way to the limitations of a human body. Riddle didn't so much fear death, but rather feared weakness.

Death was the ultimate human weakness, and mastering death would allow him to remove all weakness from himself.


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

[User]
Does the age of the universe (13.7 billion years) account of the time dilation factor caused by velocity of the earth through space relative to a object with zero velocity?

As an object gets closer to the speed of light, there is a time dilation factor, and Earth is usually used as zero. however the earth is moving within space, so does the age of the universe (13.7 billion years) include our time dilation factor? if not,what is the age of the universe for a object with zero velocity?

[Assistant] There is a reference frame in which the cosmic microwave background is most isotropic, that Earth is moving about 600 km/s relative to. There are no special physics in this frame, it is not preferred, but in it the universe is oldest and that frame is what that measurement corresponds to. However, the difference between that frame and the Earth's frame, in terms of relativistic effects, is smaller than the uncertainty on the measurement.


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

[User]
Why do stars appear to flicker but planets don't?

Is it because the planet is close and it is much less likely that another object passed in front of it before the light reached us? Or does it have something to do with emitting light versus reflecting light? or something else?

[Assistant]
It has nothing to do with the distance the light travels, because all the twinkling we see happens in the last 50 km the light has to travel. The Earth's atmosphere is solely responsible for twinkling (and is a major advantage offered by telescopes in low Earth orbit, such as Hubble).

The reason stars twinkle and planets do not has to do with the apparent size of the object. If you look at most planets through even a small telescope, you'll see that they show a tiny disc. Almost any star in a telescope, though, will show a point, because it's well beyond the resolution limit of the telescope.

Now, picture our atmosphere as a roiling, turbulent fluid made of individual turbulence cells each moving around with their own slightly different densities/temperatures. Since stars are so small from our perspective that they can be treated as point sources, the light from a star is a pencil-thin beam that can only ever pass through one turbulence cell at a time. Whatever the temperature is of one turbulence cell along that path at any time, the light has to follow. Sometimes it refracts right, another cell quickly moves into place and it refracts left, etc. - and what you're left with is twinkling.

The light beam coming from a planet, on the other hand, is much wider, and will usually pass through multiple turbulence cells at a time. The light's direction is not completely determined by a single turbulence cell's temperature, and instead the light tends to follow the path determined by the average of all the cells' temperatures it passes through. That's much more steady, and doesn't produce twinkling.

**TL;DR**: From our perspective, stars are point sources, but planets are not. Light from stars can pass through only one turbulence cell in Earth's atmosphere at a time, while light from planets pass through multiple cells at a time, averaging out any individual variations.


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

[User]
CMV: Not being able to finish his story makes George R.R. Martin a bad writer

A major part of the story is the ending. Endings can make or break stories, and I do think they are difficult to write. GRRM has been putting off ending the Game of Thrones series since he started and has changed the projected amount of books a couple of times. Many people say he knows how he wants it to end, he just doesn't know how to get the characters there, but that's the point of good writing. You get your characters there and create a great ending. Writing a story that you can't end makes you a bad writer. If he does finish the story that's a different conversation, but really I don't think he ever will because he can't because he's not a good writer.

[Assistant]
I have a different theory to proposeMartin is a good writer who no longer gets good editing.

Some writers may not need strong editing, but its clear that others do, even good ones, especially those whose strong suit is building well developed worlds.

A good editor, especially for those types of authors, provides necessary detached perspective to help the author trim out the fat and focus the text on what makes the book better.

Martin seems to have fallen into the same trap that other famous authors seem to hit.  They submit a book as a relatively unknown but talented author.  A good editor helps them polish the early work into some excellent books.

Then they get popular.  That translates into more power for a more famous and important author.  The author feels empowered to keep more of their ideas, since their ideas are clearly so good and popular.  Editors and publishers are increasingly wary of questioning their cash cow.  As a result, the books get longer, more detailed, and flabbier, with more ideas introduced than the author can possibly resolve well.   In Martins case, hes gotten so far afield that itll be nearly impossible for him to bring it back.

The other obvious example is JK Rowling and how much messier Harry Potter books got deeper into the series and pretty much everything shes done since then.   If you go into the movie world, its what led George Lucas to make increasingly bad decisions about Star Wars.    There just seems to be a type of creator who excel under constraint but go off the rails once the shackles come undone.

I dont think that makes them bad writers, just good writers who dont succeed under the wrong circumstances.


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

[User] ELI5: Is there any evidence to suggest that current animals have evolved to overcome specific environmental challenges due to human intervention? I.E. Roads, Buildings, Pollution?

[Assistant]
Yes, definitely. A very early and popular example are/were moths in Manchester in England. Basically, the moths tended to be the color of tree bark for camouflage, but in the 19th century soot from factories in Manchester caused the trees to be darker in color. Moths with darker bodies and wings skyrocketed in population while that of the tree bark colored moths declined.

Humans have impacted just about every environment on Earth and subjected the organisms within it to at least *some* kind of evolutionary pressure.


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

[User] ELI5: Why do opposite charges attract each other?

[Assistant]
It's not very satisfying but the answer is **because they do**.

Electromagnetism is one of the fundamental forces that holds the universe together.  There's not really a "why" involved, it's just how things work.


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

[User] [The Avengers] So Loki blows up a police car outside when he's in Germany, and there are a bunch of police cars behind that one. Are the police just standing there watching Loki scream at people? Why aren't they doing anything?

[Assistant] German police generally aren't the "slam you on the ground and cuff you" type. Or the "shoot you" type. More like securing bystanders and waiting for either deescalation or a SEK (SWAT). And this sounds like a situation to call in the SEK.


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

[User]
What actually kills you when you are dehydrated?

What goes on in your body that causes you to die from dehydration?

[Assistant] The two most significant issues with severe dehydration are the loss of perfusion volume as well as the electrolyte abnormalities that develop.  If someone is hypovolemic enough, they will not be able to maintain an adequate blood pressure to supply oxygen to their organs, which results in multi-organ failure (in particular, the heart, brain, kidneys, and liver are particularly vulnerable).  In addition, changes in electrolyte concentrations in the blood (most typically sodium or potassium) can result in comas or seizures as well as cardiac arrhythmias.


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

[User] [Marvel] How does the public know whether a superhero is a mutant? Why are mutants negatively received anyway, like if for some reason the Fantastic Four are revealed to be mutants would they be negatively received as well?

[Assistant] Bigotry isn't usually logical.  The Fantastic Four are heroes.  The X-Men are also heroes, but people often hate them.  The thing is, most mutants aren't heroes.  Some are heroes and some are villains, but most are just people's neighbors, and they look weird and have weird powers so people hate them.


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

[User] Are icebergs made of ocean water or freshwater?

[Assistant]
Sea ice is frozen sea water where the salt has been forced out as it freezes. Sea ice can freeze to a thickness of 2 - 3 meters but rarely gets thicker than that. Multi year ice May pile up into greater thicknesses of tilted slabs riding on top of each other to the point that some might call it an iceberg...but real icebergs hundreds of feet thick break off from glaciers entering the sea. They come from falling snow piled up year after year on land until compressed into ice. That ice then flows down hill into the ocean where it breaks off into bergs. Real icebergs are freshwater

----EDIT----

Chunks of frozen sea water aka "sea ice" are typically referred to as "ice floes" rather than "icebergs"


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

[User]
ELI5:how does a company like McDonald's make their food taste exactly the same on such a large scale?

forgive my ignorance. but a bigmac has tasted the exact same in Maimi in 1999 as it does in LA in 2004. its always the same no matter the time or place.

[Assistant]
Highly controlled food quality, highly controlled cooking process, highly controlled preparation.

That's one of their big selling points as a restaurant.  It doesn't matter where you go... the food is the same.  Not necessarily good (for you or otherwise) but its the same.  A safe bet if you are new to the area.


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

[User]
Are any of Einstein's predictions yet unproven, and if so, which would be the most groundbreaking if proven correct?

Over 100 years after they were predicted by General Relativity, gravitational waves were observed by LIGO last year. Are there any more of his predictions floating out there?

[Assistant]
Gravitational waves were only recently detected directly; we've had pretty good indirect evidence for many years.

I would nominate hidden variable theory. Einstein never really accepted quantum mechanics as a fundamental theory of the world, and said that there must be something deeper going on, something which unlike QM actually makes sense. Bell's theorem shows that this cannot be the case, so as far as we know this is a mistaken prediction, not an unproven one, but you never know: we might have missed something, and Einstein might have been right after all.


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

[User] [ASOIAF] is there still anything alive in Valyria? What possible kinds of stuff, people, monsters and the like could be found there some four centuries after the Doom of Valyria?

[Assistant]
If there weren't, then everyone would try to claim parts of Valyria due to the strategic location of the peninsula remnants. But everyone who sails there (except Jorah and Tyrion, who sailed in the show) doesn't come back.

 If the sailors' ships didn't break apart from encountering rogue cliffs hidden in mist and ash, then some sea beast could claim them. If the sea beast didn't claim them, then they probably got lost because of the mist. And if they ran out of supplies while trying to find open water, they'd try to forage for something... when there's nothing left. They're now stuck in who knows where without food.  They resort to cannibalism and none return home.

So many things could go wrong; especially when nobody managed to make a clear map of Valyria (because the cursed land is unnavigable). Whatever lives there has a hand (or claw, or fin) in the disappearance of all who sail there. And even if the beasts don't do anything, the land itself dooms the sailors.


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

[User]
ELI5: How can communities where polygamy is common, have a large enough quantity of females when the the boy to girl ratio is around 1:1 ?

I have mostly Fundamentalist Church of Latter Day Saints and Muslim communities in my head but i know that there are plenty more that have polygamy as a part of their culture/tradition.

[Assistant]
These communities typically fall into one of two categories:

1) Males tend to have higher death rates than females, likely due to active armed conflict with another group

2) Most males, for one reason or another, are socially ostracized and kicked out at a young age, leaving more women than men remaining in the community.


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

[User]
ELI5 Why I should buy locally?

What are the benefits?

[Assistant]
One of the biggest reasons is that it costs money and fuel to bring things to you...bringing a banana from South America to your local supermarket in New York City before it goes bad means spending a lot of gas.  Most scientists are convinced that the Earth is getting hotter due to too much carbon emission, mostly from burning gas, coal and oil.  By buying locally, you can cut down on a lot of this wasted fuel - it's just more efficient.

Some scientists are also concerned about the long-term effects of taking, taking, taking from an area without giving back - some countries that export bananas, tobacco, etc. end up depleting the soil and need to pay for (mostly) oil-based fertilizer, which means using up oil and gas even faster!

Another reason is more controversial: if you buy locally, you'll keep jobs in your area, which means more people with money who will spend at least some of their money locally, too.  The more jobs you can keep here instead of "over there," the more jobs will be created to take care of those working people, so the better off the whole community will become.  Of course, these jobs are coming at the expense of people "over there," and not all these jobs are well-paying, and people don't always spend their money locally, but it's an idea a lot of people like when there is a lot of unemployment.


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

[User]
ELI5 What is log and natural log??

I just dont get it. From high school til now post college graduate, I still dont know what logarithms are.

[Assistant]
Suppose we have two numbers, X=2 and Y=8.

Log simply asks: how many Xs we need to multiply together to get Y?

Or in this case, how many 2s do we need to multiply together to get 8?

Since 2 x 2 x 2 = 8, the answer is 3.  We need to multiply 2 by itself 3 times to get to 8.

In math notation, we write this as log(Y) or in our case: log(8) = 3.

Sometimes we call X (2 in our case) the "base".  It's just the number we want to multiply several times to get to Y.

Turns out, for various calculations we are interested in multiples of the *natural constant* "*e*" (2.71828...).

Rather than writing log(Y) or log.(Y) every time, we just abbreviate it as *ln*(Y) where *ln* stands for "natural log".

So "natural log" is just log with base = *e*.


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

[User]
ELI5: Why is the Periodic Table shaped the way it is?

I have basic knowledge of chemistry, but I've never received a straight answer on this.

[Assistant]
To assemble the table:

* Line up all the elements according to the number of protons in their nucleus (hydrogen 1, helium 2, and so on).
* Noble gasses stand out because they're chemically inert (I'll get to why later). Take this long line and split it at every noble gas to make a new row, keeping the noble gas on the right edge.
* You'll end up with some elements above others with different chemical properties. For example sodium would be above copper when it is much more similar to potassium. Introduce gaps so the chemical properties match vertically and you'll end up with the periodic table.

If you're ok with this explanation the rest is just chemical detail and tl;dr.

*Why* it behaves like this is because of electrons. Noble gasses have complete electron shells and therefore are inert. The first column has one electron in its outermost electron shell, and is therefore very reactive, the s shell can hold two electrons so that explains column 2.

The transition metals (centre of the table) are filling up the d electron orbitals, the first d shell isn't filled until after the 4th s shell (4s), that's why they don't appear until the 4th row of the table; the d shell can hold 10 electrons so the gap is 10 elements wide.

The elements on the right hand side have full (or missing) d shells and will fill up their p shell, which can hold 6 electrons but isn't used until after the 2s shell is full, which is why hydrogen and helium stick out the top of the table.

The block at the bottom of the table can also be visualised as slotting in between columns 2 and 3 of the main table. These elements are filling their f electron shell, which isn't done until after the 6s shell is full.

Why are shells filled in this order? Because putting an electron into the 5f shell takes a lot more energy than putting it in the 2s shell, electrons will fill shells from the lowest energy up.

EDIT: Formatting

EDIT2: There are other forms of the table that don't have gaping holes in the top, you can find them on Wikipedia.


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

[User] ELI5: What is that hiccup like thing I feel after eating a big meal?

[Assistant] Irritation of your diaphragm, which is a muscle under your lungs that allows a good ventilation (by allowing your lungs to expand when inhaling and decrease when exhaling), is a known cause of hiccups. After a big meal, your stomach is full and may irritate your diaphragm. Ingestion of air may also be a factor.


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

[User]
[DC] Would the Joker in all of his psychopathy have any sexual urges/inclinations?

Is he capable of such basic instinct?

[Assistant]
Depends on which one you're talking about. The DCAU Joker definitely had and enjoyed sex with Harley. Apparently whoopie cushions and cream pies were involved.

The Joker that we saw briefly in Azarello's Joker raped his henchman's wife.

And in the post-Crisis, pre-Flashpoint continuity, there was a point where he thought Batman was dead and gave up his identity as the Joker to become Joseph Kerr. He settled down, got a job, and, IIRC, even got married before seeing evidence that Batman was alive again and running out on his girl to become the Clown Prince of Crime once more.


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

[User] ELI5: How does something become a commodity and what does that mean for public access to the item - like water, gold etc?

[Assistant]
Generally commodities are less expensive than otherwise due to the greater competition between suppliers. If you want gold then any gold will do from anyone who has it, but if you want an iPhone only Apple can produce it.

Of course this doesn't mean that a commodity is inexpensive overall, gold being an example. It just means there aren't any differentiating features between one supplier and another.


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

[User] [Civilization] Why does Gandhi decide to become imperialistic?

[Assistant] Gandhi is a cold-hearted cynic who will use any tactic necessary to win. In the case of 1940s India, he knew the best tactic was a form of non-violent protest to embarrass the British. However, if he had had nukes, then we'd have seen Mushroom clouds from London to Edinburgh.


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

[User] ELI5 What is the Boehner Bill that just passed? What does it cut?

[Assistant]
The bill passed the House of Representatives but was rejected by the Senate.

In the United States, in order for a bill to become law it must:

- Pass the lower house (House of Representatives)
- Pass the upper house (The Senate)
- Be signed by the Executive (The President)

This bill cleared the first hurdle but never had any chance of passing the 2nd or 3rd.


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

[User] ELI5: Why does paper product (paper towels, napkins, etc.) become transparent when wet?

[Assistant]
Imagine you are at a restaurant with a self-serve soda dispenser and a clear glass cup.   First, you fill the glass with that finely-crushed ice they have at soda dispensers.  Now look through the glass.  What color does it look?  White.  Opaque.  Like a white paper towel. You cannot see through the glass at all.  If there was an object (like a cell phone cover) behind the glass, the ice obscures it completely so you can't even tell what color the object is.

Now fill the glass with cold water (or Sprite).  Most of the crushed ice is in there, but now the glass is translucent.  Like a wet paper towel.  Although you couldn't read a book through it, you could certainly see the color of an object behind the glass.

When ice and air are mixed in a glass, their very different indexes of refraction make light beams bounce around a *lot*, mixing everything up until you can't see through it.

When ice and water are mixed in a glass, their index of refraction is the same (in fact, if the ice itself didn't have air bubbles inside it, the glass would be almost completely clear and see-through).  So less bouncing of light beams.

The wood pulp and other material in paper has an index of refraction closer to water (and ice) than it does to air.  So the effect is the same.


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

[User]
ELI5:Voyager 1 is the farthest spacecraft traveled from Earth, where does it find all of that fuel and how can scientists still manage to control it?

Question number 1: I understand that the Voyager 1 is a probe and there is no gravity or air resistance in space so you can move a great distance with little force but it still need the fuel to propel itself or change direction from time to time and it has been traveling for a very long time, so where does it find all that fuel?
Question number 2: the Voyager has gone out of the solar system, which is VERY far away, how can they still manage to control it? what method did they use?

[Assistant] It has very little if any fuel left. It is simply just flying through space. You said it yourself there's no air resistance. Now that it's moving it doesn't need any fuel to keep moving. They dont change direction ever. They don't really do much control anymore. They just receive data from some of the sensors. If they do want to control it they have to issue the commands in sequence so that voyager can execute them automatically once it receives them.


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

[User] ELI5: What gives the USD value if it is no longer backed by gold?

[Assistant]
Trust.  All forms of money are based on the trust that it will be valued when it is time to exchange it again.  Whether it is elements and minerals, like gold, or paper currency and coinage, when a person accepts it as compensation, they are trusting that when they go to give it as payment, it will be accepted.  Even gold only has value because we all trust that it does.  A person who accepts gold (or gold-backed currency) in payment, does so because they trust that when they try to give that gold to someone else, that person will accept the gold as valuable.

Currency is trusted because the government that created it says its good and will be acceptable.  That's one of the factors accounting for the fluctuations in currency exchange rates.  How confident are people that the government will continue to be able to back the money they issue.


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

[User]
[Sea Lore?/Pirates of the Caribbean] Was the Flying Dutchman ever going to be upgraded as time went on? Like would Davy Jones be attacking modern battleships in that Galleon?

I admit I'm not very familiar with Davy Jones and all that. But he apparently interns sailors for up to 100 years, so even from the Golden Age of Piracy on at the latest he'd be fighting some of the most powerful sailing warships ever built. Would he keep going as time went on in the same ship or?

[Assistant]
Pirates, traditionally, avoid fighting warships seeing as warships have lots of war and not lots of loot, this being the opposite ratio that pirates generally go for when they attack things.

So, yeah, I'd say it's likely the Flying Dutchmen was upgraded significantly and repeatedly over the years... but likely not with multi-inch gun/cannon, but with better engines to catch ships with lots of loot.


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

[User]
[DC] Since the Flash always "stands" on the surface, doesn't that mean his weakpoint is under his feet?

Flash is extremely overpowered, that much is given. I was wondering what if someone booby trapped the ground itself so that you take out Flash's greatest weapon: his feet. technically he can't phase through the ground because he's always standing on the surface, so unless he's fine falling inside the Earth, it seems like his main weakness are the soles of his feet.

[Assistant] He can phase through the ground. He just usually stands on it. He doesn't automatically phase through things or turn it on and off. He has to carefully match his vibrations to whatever he wants to phase through. If he wants to start walking underground, he just has to not match frequency with the ground further down and he can walk on that.


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

[User] ELI5: how we know that the universe will die and no new stars will form?

[Assistant] Stars are made from certain elements.  They have to also be collected into nebula.  This can't go on forever.  In fact, by looking at star formation in the past and star formation now scientists can see that star formation is really low now.  Most stars to ever exist already have.


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

[User]
ELI5: Bacteria become resistant to antibacterial products but why not bleach and alcohol?

I understand that some of the bacteria survive the antibacterial products and the ones that survive are more resistant, however why doesn't some bacteria survive alcohol or bleach and become more resistant to those products?

For example, if I swap my skin with alcohol even if the bacteria under the swab are all killed when there be some on the edge that would survive but get a partial dose of alcohol?

[Assistant]
Imagine a bacterium as a big factory, with the bacterium's membranes and cell wall being like the factory's walls and ceiling, the enzymes like the factory's machines and the DNA like a big book of instructions for building the factory.

An antibiotic is like sending a saboteur into that factory - maybe to break a critical piece of machinery, or to blow up a structurally important support pillar. The factory could counteract that sabotage by, say, positioning guards that could catch the saboteur (similar to how bacteria may become immune to an antibiotic by mutating an enzyme that can break down the antibiotic.

Bleach or alcohol (or also heat) are more like carpet-bombing the factory until just a pile of rubble remains - they damage a bacterium in many different places at once, and in a much cruder manner. That is also why you cannot use them internally to fight an infection - they would cause too much collateral damage to your body's cells.


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

[User]
ELI5: How are telemarketers benefiting by calling me and hanging up without saying anything?

I get these calls all the time from random numbers, and when I answer there's no one there.  A lot of the time when I call back it will say "You have reached an nonworking number."  How is that benefiting whatever company is calling, if they're not even trying to sell me anything?

[Assistant] As soon as a telemarketer is free for a new call, their systems will dial multiple numbers hoping that someone will pick up. The first person to answer is lucky enough to talk to the telemarketer, the rest of the calls are either kept on hold waiting for another free telemarketer or hung up on.


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

[User]
ELI5:How did they figure out what part of the blowfish is safe to eat?

How many people had to die to figure out that one tiny part was safe, but the rest was poison? Does anyone else think that seems insane? For that matter, who was the first guy to look at an artichoke and think "Yep. That's going in my mouth."?

Edit: Holy crap! Front page for this?! Wow! Thanks for all the answers, folks! Now we just have to figure out what was going on with the guy who first dug a potato out of the ground and thought "This dirt clod looks tasty!".

[Assistant]
Well, you've got a bit backwards. A small portion is dangerous, and most of it is safe. If it were nearly all poisonous, it probably would never have become a food.

 The dangerous part contains a chemical which is so fast acting that you can feel its effects on you within seconds after touching it to your tongue. So it's not that hard to figure out which part contains the poison.


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

[User]
[Star Wars] What did Palpatine go splat on after Vader tossed him down the hole?

The hole couldn't be too deep since the Force explosion happens pretty quickly after Palpatine gets thrown.

[Assistant]
He smacked into a plasma conduit on the way down. It wasn't enough to kill him, but it was enough to break his hip and let loose a blast of super-hot plasma that fried his hair and clothing and made that impressive display back up at Luke's level.

After that, Palpatine continues falling towards the core, blacked out from the pain, caroming off the walls like a pinball, before finally arriving at his destination.


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

[User] ELI5: If I swat at a mosquito and miss, will it remember/fear me? Or does it just dodge on instinct and go back to its usual buzzing around/hunting?

[Assistant] Insects only have a basic nervous system, so they're not capable of that kind of memory. Essentially, when a mosquito dodges a swat, it's because they interpret moving shadows/lines as predatory movement. Their compound eyes augment this survival reflex.


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

[User] [Star Wars] Did many people know Darth Vader's true identity or how he became trapped in a life support suit?

[Assistant] No. The official story is that Darth Vader is the right-hand man of the Emperor. If you fucked up, if the mess on your hands was beyond your capacity, if you were a high enough position to commit treason and have done so, if Jedi presence was confirmed to be there, Vader is who the Emperor will send to clean it up.


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

[User] ELI5 why we should wash our hands with comfortably warm water. Isn't that the ideal temperature for germs and bacteria to grow/multiply?

[Assistant]
It is, but we're not really worried about bacterial growth *while* we wash our hands. We're not even usually worried about bacteria *growing* on our hands at all the danger is that we'll transfer germs, via our hands, to a new place (inside out bodies, on our food, etc) where they can grow out of control.

Meanwhile, warm water makes soap more effective at removing germs from our hands, interrupting their movement before they can reach places they'll be dangerous.


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

[User]
What exactly makes things "cute"?

What is it about puppy eyes or sleeping kittens that are appealing to humans? Why can it also apply to inanimate things? (i.e. A "cute" hammer) And why, when I see a really cute picture do I sometimes feel that it's "too cute" to stand, and I want to physically grab/eat/coddle it? Does the base idea of cuteness apply to all humans? Was it like this in the, say, 1500s?

[Assistant] In human evolution, natural selection favored parents who had strong, positive feelings for their infant children. Puppies and kittens have similar geometric shapes to their faces as infants. It's a simple matter of mistaken affection that actually worked out pretty well for all parties involved.


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

[User] ELI5: How do they make such complex ASCII art?

[Assistant] Usually with computer programs. There are many different approaches to generating an ASCII image, depending on how you want your final image to look. For example one simple method would be to transform a picture into a low-resolution grid, where each cell in the grid is assigned a letter depending on the brightness of the picture inside of that cell. It's also possible to mimic certain patterns in each cell, for example a "`L`" can be used to represent a right angle, a `#` can be used for heavy shading and a `+` for light shading, etc.