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

[User] How do we know what temperature absolute zero is? Could we reach that temperature and find that the true absolute zero is 0.1K cooler?

[Assistant]
By definition, absolute zero is where a system is in its quantum mechanical ground state. Thus, it is a system at the minimum energy it can possibly take - it's impossible to extract any more energy or heat from it.

(Absolute zero is not really "the absence of motion" as many people seem to think - a system in its quantum mechanical ground state can have very large fluctuations in position and velocity. This is still consistent with zero temperature and zero thermodynamic entropy.)


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

[User]
Does a perfect sphere have zero, one, or infinite faces?

Does a face have to be flat?  Then it would be zero, right?  If not, I would think the answer is one.  But if you had an approximation of a sphere, like a polygon but 3d, the more faces you added, the closer to a sphere it would be.  So along that line of thinking, infinity faces would yield a prefect sphere.  Help.  Thanks!

EDIT: Thank you everyone for your answers!  Very interesting!

[Assistant]
It doesn't have any faces (i.e., 0) because a face is a part of a plane, therefore flat. Infinite faces would yield a perfect sphere--with faces of zero area--but infinity is not a number, so you can't really get there. If you've the mathematical interest to pursue it further, the concept you're brushing up against is that of a "limit", which is the magic glue that holds the Calculus together.

(B.S., Math '93. Lots of folks who know a lot more will answer more precisely and rigorously.)


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

[User]
Why do we launch space-bound shuttles straight up?

Why do we launch spaceships straight up? Wouldn't it take less force to take off like a plane then climb as opposed to fighting gravity so head on?

[Assistant]
It's like in Mario Kart where if you drive off the side into the mud, the drag slows you down. If you drive back to the road in a perpendicular fashion, you minimize your time in the mud, but you've built up no momentum once you get to the road. If you drive parallel and angle yourself gradually toward the road, you maximize your time in the mud and waste a lot of energy, but you get to keep whatever forward momentum you've gained once you get to the road. Depending on the thickness of the mud, there's some optimum angle that describes the most efficient path back onto the road; approaching perpendicular for thicker mud, and approaching parallel for thinner mud.

Now if the thickness of the mud/atmosphere *decreases* as you get closer to the road/space, that optimum path would be a curve, starting at perpendicular and ending at parallel, and that's exactly what rockets do.


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

[User]
[Westworld] What is at the borders of the Park?

I'm sure that they discuss this in the ~~show~~ Documentary-Series somewhere, or in the the earlier ~~film~~ Documentary, but what exactly stops the Hosts from wandering off?

[Assistant]
1. The parks are on an island, so the edge of them is ocean.
2. The hosts' programming keeps them from going where they're not supposed to.
3. The hosts have explosives in the base of their spines that will automatically detonate if they somehow leave in spite of the physical and behavioral safeguards.


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

[User]
Can you help me understand Camus?

So a while back, I read "The Stranger" by Albert Camus. But I am struggling with the understanding of its message. The main character goes through the book's events in an almost trance like state, and I am assuming that it is to showcase the absurdism of the human existence and the normal world, which we rarely question as normal humans in our everyday lives. But I can't help but feeling I am missing a piece of the puzzle, and I am wondering if any of you can point it out to me?

I do apologize for my any lack in my english, I am not a native speaker.

[Assistant] Camus is trying to paint the existential perspective that many people feel. The absurdist thoughts experienced in the book, are almost comparable to the platonic cave. Once you come out, it's quite hard to rationalize any true importance for a lot of pieces of one's life. Simply, he doesn't quite care and floats through life.


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

[User] [Star Wars] Why is it OK to bring down lightning from the sky, but evil to shoot it out of your fingers?

[Assistant]
What yoda did was simply manipulating nature a bit. There was already bad weather, a lightning blast is simply nudging nature in a specific way. This is in line with the way the jedi use the force, they dont bend it to their will, they nudge it along.

Force lighting, however, isnt. Its not even natural electricity. You dont create a pathway of ions in the air for the lightning to travel, you dont build up a charge in yourself then fire it out to even out a static buildup.

No, force lighting is hate embodied. You literally shoot *hate* out of your fingers, what you do is that you bend the force to your will becasue you wanna hate your enemy to a painful death. You bend a natural power of the universe to your will to literally hate someone so much they cease to exist.


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

[User] [Invincible] Why do so many male Viltrumites have receding hairlines, besides Mark, Nolan, Thragg, and a few others?

[Assistant]
I assume because their hair is the least durable part of them, and they keep flying headfirst into things.

It's like humans and constant hot showers. Not enough to do any harm, but over years and years it speeds up hair thinning.

Nolan's hair is clearly stronger than most. Or he's mostly been dealing with Earth-level threats and that isn't as rough on the hairdo.


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

[User] [BATMAN 1960s] What exactly are the mechanics behind sliding down a pole and emerging at the bottom dressed as batman?

[Assistant]
On the way down the Bat-Pole, \[Name Redacted\]'s lounge suit and flawlessly tied ascot are automatically removed by the Bat-Stripper (little known fact: Strippers, Bat or other, are frequently found in the vicinity of poles, Bat or other) and replaced using the Bat-Dresser, which is of course pre-loaded with the Bat-Suit.

By the time he reaches the Batcave, Batman is therefore one hundred per cent Bat-ready for action.


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

[User] ELI5: How is 5G going to interfere with weather satellites?

[Assistant]
Some of the frequency bands that are expected to be used for 5G are currently the bands that most weather radar use to detect precipitation feedback in the atmosphere, as that makes the "noise" of different "intensity" to show what we know has a weather radar sweep.

Those frequencies, if used in 5G communication will give false positives on weather radar in areas of high usage (i.e. cities) causing major weather forecasting computer models to spit out bad data that it can't compensate for.


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

[User] Eli5 why does my band-aided finger feel like it has a heart beat?

[Assistant] because it does, it has your actual heart's beat. as does just about every bit of you. the band-aid is just putting pressure on it, so it actually becomes noticeable. maybe it's on a bit tighter than it needs to be.


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

[User] ELI5: Why does an inmate on death row need a medical check before an execution if they're going to die anyway?

[Assistant] Because the United States feels that when they preform the death penalty, it is important that it is done in a way that is quick, clean, and does not induce unnecessary suffering. The medical check is there to make sure all three of those things can be assured.


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

[User] ELI5: why is it when during the winter I have my heater set to the same temperature as I have my AC during the summer, and yet I'm cold in winter and warm in summer?

[Assistant] To some extent this is a psychological effect.  In cold weather you tend to worry about being too cold, and in hot weather you tend to worry about being too hot, and this alters your subjective perception of the room temperature.


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

[User] Why hasn't another massive meteor struck the earth like the one that killed off the dinosaurs?

[Assistant]
Because Earth getting hit by meteors large enough to cause mass extinctions are extremely rare events. Also, Jupiter usually shields the Earth from incoming ~~meteors~~ comets although sometimes it can also slingshot them in our direction. With Jupiter catching ~~meteors~~ comets and asteroids that come from outside our solar system and throwing them back out again, the timescale for significant collisions between Earth and large objects are millions or tens of millions of years.

EDIT: Formatting and stuff.


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

[User]
ELI5: How do bricks work?

Are they structural to making buildings stay up? Or just an attractive exterior? Are there different types? How tall can a brick building be before the bottom bricks break under the weight of the bricks above them?

[Assistant]
They used to be structural but today most cases they are more for the thermal mass and the style.

Most buildings are wood/steel/concrete structurally today with the brick layer is only an outer layer that provide:

- Mass to help control temperature
- Protection from the elements
- Style

You can identify that a brick wall is of this type because all the bricks will be lengthwise ("wide") across the entire wall (usually).

In older buildings they do have a structural function. In these cases a brick wall isn't just one layer of bricks but several layers stacked and interlocked together. You can identify these because every few bricks in height you will see a row of "thin" bricks. These are bricks layed inward so that the outer layer will interlock with the next layer of bricks.

The total height they can support is based partly on the thickness of the wall (something like a height of no more then 20 times the walls width at the base), though it's fairly rare to see a building of this type taller then 10 stories as it becomes increasingly more complicated to make a brick building taller without another supporting structure.


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

[User]
ELI5: Why does wood burn when you heat it up instead of melting?

Not just wood, but many things burn instead of melt, whereas other things melt instead of burn. Can you burn ice? What if you put ice in wood?

[Assistant]
There are two major forces at work here. The first is the chemical bonds themselves. This would be the carbon-carbon and carbon-hydrogen bonds (among others) that hold a single molecule together. The other force is intermolecular forces, which hold a bunch of molecules together into a cohesive unit. As an analogy, chemical bonds are what make Lego pieces hard to break, while intermolecular forces are what make an entire Lego structure hard to break.

When you heat something, you're putting a lot of energy into it, in the form of vibrations. These vibrations strain against both of those two forces.

If the chemical bonds break first, you get combustion. The individual atoms start flying apart and shedding energy as heat before finding something else to bond with (usually oxygen).

If the intermolecular forces are overcome first, then the thing melts. Molecules start sliding against each other, and the entire structure starts to "flow" like a liquid.


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

[User] ELI5: Why do so many loading screens go to 90% really quick, then take just as long or longer to finish the last 90%?

[Assistant]
Here is one example:

A progress bar shows the total progress of all tasks being done. Each individual task might be different and it may not be easy to determine how long it will take (some recursive functions).

So instead of calculating the progress of each task, it will just move the progress bar forward each time one is completed. So say there are 10 tasks to do:

    Task 1 of 10 complete, move the bar to 10%.
    Task 2 of 10 complete, move the bar to 20%.
    Task 3 of 10 complete, move the bar to 30%.

And so on. Each of those tasks can take longer than the other so the progress bar can appear to jump in some places and stop in others, instead of a smooth transition from 0% to 100%.


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

[User]
[Scooby Doo] How are Scooby and Shaggy thin despite eating so much?

Shaggy and his canine friend, Scooby Doo, can eat insane amounts of food in a single sitting. They don't always eat the healthiest foods. How are they not 300 pounds?

[Assistant] Shaggy is constantly running away at the speed of Scooby. Great danes can run at 30 mph which is faster than Usain Bolt. Whatever calories they intake are quickly burned away by them constantly running at such high speeds.


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

[User] ELI5: How come standard cars aren't fitted with roll cages to make them safer during accidents?

[Assistant]
Ever wonder why race-cars doesn't have doors that open?

It's the rollcage that's in the way. There's (at least) two massive metal tubes that goes through where the door is.

However, your standard car has a rollcage, of sorts. The chassis is designed in such a way that it acts as a deformable rollcage.

Why a deformable roll-cage?  Wouldn't a stiff one (like in the race-cars) protect you better?
Well, yes, and no. A stiff roll-cage makes the whole car very stiff, making you absorb a lot more of any impact. You want your car to crumple as much as possible (without crushing you). That means that you get to absorb less of the energy from the crash.


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

[User]
[MCU] Do versions of Thanos try to enact their plan in the spiderverse's original universes?

If there are different versions of Spiderman, does that mean that there are different versions of Thanos too, and each one has their own infinity war?

[Assistant] There's no way of knowing unless one of them mentions it, but it's possible. The thing about the Multiverse is that one universe can be **extremely** different from the other. That means that in one universe Thanos went after the Infinity Stones, in another he never bothered with them, whereas in some other universe Thanos doesn't even exist or was killed early on. *Anything* is possible. So, no, it doesn't mean that each universe went through an "infinity war" or similar event, but there are definitely many universes where their Thanos went after the Stones.


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

[User] ELI5: Why did America lose the Vietnam War despite having an overall superior army and economy?

[Assistant]
The Vietnamese were guerrilla warriors all the way and used ingenuity over might. Here are just some of the low-cost tactics they used to defeat the U.S. army:

1) When they discovered that Americans were using "jumping landmines", as in when you step on them they spring up and explode in the air, they had their scouts follow US troops and spot where they were planting them and risked their lives to dig them up...and plant them in the tops of trees to that when US copters flew over the trees, the downward pressure of the rotors would cause the mines to jump and explode at the helicopters.

2) Manipulate curiosity - The VCs noticed that many Americans had a childlike curiosity. So if they planted a Mickey Mouse doll in the middle of the jungle, troops would invariably be like "wow, what's this doing here?", pick it up and trigger a bomb.

3) Insect warfare - Living in the jungle, VCs were accustomed to seeing scorpions and tarantulas all over the place and quickly realized they freaked out Americans. If they didn't have bombs at their disposal, the VC would rig boxes full of spiders or scorpions and a trip wire would bring them down on US troops who would shriek in horror, thereby giving away their position and getting mowed down by gunfire.


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

[User] How does Green screen work?

[Assistant]
If you want to use a computer to put an image onto a video, you pretty much have to do it frame by frame. Modern software can speed this up a lot but sometimes you just want to change a background or something.

So you pick a colour that you know will not be in your frame, make sure its evenly lit up. Then you have some software that will replace the green in the video with whatever you want. For this, a light green is usually chosen.


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

[User]
[Star Wars] Could Darth Maul use Force Lightning?

He had been training with Sidious since he was a child, so did Sidious ever think to teach him?

[Assistant] No. He thought explicitly NOT to teach him. Force Lightning is sort of an end-game power. It is the very last thing you learn, something that requires almost complete mastery of the force to utilize. And Sidious had no intention of EVER teaching him that, because Sidious has no intention of furthering the Rule Of Two. Under the Rule of Two, once Sidious had taught Maul everything, Maul would rightfully have killed Sidious and become the master, so Sidious kept his teachings to a minimum. That way, his apprentice could never rise against him.


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

[User]
How did the evolution that produced the Angler fish work, especially the sexual dimorphism?

If evolution is just a series of small mutations, wouldn't males getting smaller and weaker jaws make them less likely to survive? How did the parasitism even evolve? Did a male angler fish suddenly think, okay I'm just going to bite this female, and somehow they fused?

[Assistant]
So consider the environment most angler fish live in. Most live in dark areas with limited resources. To make things harder they eat living things rather than dead things. Living things are kind of rare, but it's how the angler fish do. The female is the primary producer of children, so in order to produce lots of children you need a lot of energy. This can't happen if you are competing with your own species. So to combat this the males get smaller and require less energy. In addition, males are programmed to seek out the female and attach. Some females in nature (namely geckos) store sperm cause your don't know when the next meeting will be. Angler fish take this a step further and basically collect gonads.

Edit:a word.


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

[User] What's happening in your body when you 'sober up' due to panic?

[Assistant] Catecholeamine release. Norepinephrine and epinephrine are endogenous sympathomimetics that have a variety of functions but are best understood in the context of the 'fight or flight' response in the sympathetic nervous system. This response primes the body for activity that may be crucial to survival. Effects include increased heart rate and blood pressure, shunting blood away from the gut to the muscles, raising blood glucose levels, and increasing alertness and reaction time. In the setting of alcohol intoxication the effect can be a perceived sense of sobering up, however judgement, coordination, and reaction time may still be impaired.


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

[User]
[X-Men 2] What happened after Xavier almost killed everyone with Cerebro?

In X-Men 2, Professor X is plugged into Cerebro and focuses on all the humans for what seemed like 15 to 20 minutes, causing *every human on earth* to writhe in pain.  Did he actually kill any of them?

Then, the President is in the middle of making a speech to the United States calling out the mutant threat, but is interrupted and threatened by Xavier and the rest of the X-Men and is convinced not to.

What does the President say instead?  He was already on television making this speech after a world-wide phenomenon which was likely a huge massacre at the hands of a mutant.  The President must respond to this outrage, so how does he handle it?

**Bonus:**  And speaking of Professor X in this movie, he is capable of time-freezing an entire museum full of people.  When he time-freezes the President's office and filming crew, as far as we know, the President's address was still being broadcast.  If this speech was live, did X really freeze the entire country during his little intervention with the President?  Just how powerful is Professor X?

[Assistant]
1) Several how were in aircraft or driving died. Otherwise, everyone was ok.

2) He responds by explaining that it was Stryker who did the deed and that Stryker is dead.

3) He only froze the people in the room. Professor X needs cerebro to go much farther than that.  He did short out the screens so the US audience didn't see anything. We don't know his limits but in the movie universe he isn't a level 5 mutant.


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

[User]
Do two waves have to have the same frequency for interference to happen?

I can't find a clear answer to that.

If i understood it right, fourier synthesis lets a bunch of waves with different frequencies interfere to model a complex one. So it should be possible for two waves with different frequencies to interfere, right?

[Assistant] Waves with different frequencies can indeed interfere. In acoustics, the interference between two sounds of close (but not equal) frequency is known as a *beat*, being perceived as a single tone with varying volume. If the frequencies are a little further apart you can instead get a *combination tone* related to the difference between the frequencies.


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

[User]
ELI5 Why are close shots in older TV far better quality than wide shots?

Just watching Seinfeld and I noticed a marked difference between the close shots and the wide shots. It looks like it might be restored, but why could the close shots be restored and the wide ones not?
My only other thought is there's too much going on in the background for the camera to display at the same resolution, but I think that's been a more recent issue.

[Assistant]
The used stock footage for a lot of the wide establishing shots. It's super noticeable now that you can watch the show restored in 4k from the 35mm negatives.

Most of the 'outside' parts where shot on a backlot which gave them a certain amount of street to shoot on, but by no means everything they would need for every single script.

When the show first aired the crappy standard definition stock footage was mixed in with a standard definition scan of the film negatives, so it was less noticeable of a jump.


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

[User]
ELI5:Antibiotic Resistant Bacteria

I have heard a lot about antibiotic resistant bacteria and how dangerous it is. Can anyone explain how we got into this dangerous position and what this implies about the future of bacteria? How possible is a worldwide outbreak pandemonium based on this?

[Assistant] Basically what happened was that antibiotics were used so often, even for simple stuff such that the bacteria became resistant by natural selection. Once in a while, mutations may create a bacteria resistant to antibiotics. When antibiotics are used, all bacteria not resistant are killed off, leaving only resistant strains to reproduce and multiply, passing on their resistance. Thus, all the bacteria are now resistant to the antibiotics. Now we have to make new antibiotics to combat these bacteria.


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

[User] ELI5: What is it in peoples genetic makeup that makes things like weight problems hereditary?

[Assistant]
For the vast, vast, vast majority: nothing.

Weight problems weren't "hereditary" until the last 50 years or so, and amazingly, they still aren't "hereditary" in the third world. Truly shocking.

Human metabolisms don't vary by more than a few percentage points (accounting for obvious things like sex/height/etc).

Everyone has that one friend who supposedly eats a ton but never gains weight, and they have that one friend who eats "omg so healthy" but looks like a blimp. These are not exceptions. People are just really, really bad at estimating how much they themselves eat, and even worse at estimating how much others eat.

Thyroid issues don't make people obese, either. They usually only account for a ~5% difference if untreated and a 0~1% difference if treated.

The only reason fat parents tend to have fat kids is because they instill bad eating habits and don't teach the concept of delayed gratification to their children.


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

[User] Why are certain things like knives/swords forged when they could may as well be cut and sharpened from a sheet of metal?

[Assistant]
Most cheap knives are either cut and ground or die-forged (a blank or sheet is stamped at very high pressure to smoosh it into shape, then ground to finish). Die forging or stamping is quick, cheap (per unit, not to set up), and pretty efficient use of material.  Decent knives are then heat treated to the desired hardness, sometimes differentially (edge is hard to keep an edge, spine is more elastic so it doesnt snap)

Grinding a thick blank into a sword or knife can be time consuming, lead to spot-overheating and distempering of the metal, and wastes a lot of metal. Small-scale makers will sometimes do this.

Hammer and anvil forging is kind of hipster-y cool but also allows for mixing different steels together and delivers a unique product every time. Its also hella expensive in terms of time, but doesnt require a couple million dollars worth of press and dies. Most commercial swords and knives are not hand forged.

Theres a whole spectrum of methods between these - its just a quick survey of high points.

Edit: clarity.


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

[User] [Harry Potter] What was the point of the Triwizard Tournaments first two tasks if the winner is decided entirely by whoever touches the cup first in the third task?

[Assistant]
Spectacle, and advantage in the final task. And this way, they avoid the final task ever being rendered pointless. No matter how poorly a school does in the first two tasks, they *always* have a chance to win the tournament. If the tournament was decided by, say, the point totals of the three tasks, it would be possible to enter the third task with no possibility of success.

Not fun for the participants, the schools *or* the audience.


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

[User] Why don't cars just have AC outlets rather than "car outlets"?

[Assistant]
Your car's electrical system is run off 12V DC (you know, battery power). Your household current is (probably) 120V AC.

There are some cars that do indeed come with AC plugs installed, but behind those AC plugs are power inverters. It's important to note that whatever is plugged into the AC outlet will still draw the same current; if you have a 100 watt item on household 120, that item will only draw .83 amps. On the other hand, if you use an inverter and plug that same 100W load in you're drawing almost 9.2A on the DC side (100/12V, and assuming 90% efficiency).

Converting AC to DC is simple; you use a diode bridge and chop the waveform to a good DC approximation, maybe with a snubber diode or two for good measure. Converting DC to AC requires taking DC and simulating an AC waveform, which is considerably trickier.

Given that the equipment necessary to invert your car's power to household power and the amperage draw required to run most equipment, it's just not a done thing to install AC outlets in a car (aside from a few exceptions). It adds substantial cost and complexity as well as risk (what happens if an end user wants to run a hair dryer? An 1,800W hair dryer at 120V is 15A; that's 165A @ 90% on 12V DC! That's more than a Honda Accord alternator produces!). Cars that are equipped with AC outlets must be designed to accommodate them, and end users mustn't treat them as they would a common household outlet.


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

[User]
Why don't we digest tapeworms?

Our bodies are pretty good at digesting lots of things.  How do people get a tapeworm without it being dissolved and used for food?

[Assistant]
It is as simple as them having acid resistant outer skin layer.

It is the same reason many other things are not digested, for example hair: It simply does not react with anything in the digestive tract. Just like hair, the outer skin of parasitic worms evolved not to react with their hosts digestive secretions.


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

[User]
[Star Wars] Does anyone think that Anakin would have been a fallen Jedi even without Sidious' influence?

He clearly has a lot of differing opinions from the Jedi, and the Jedi were shown to have stagnated in a way - or perhaps they were out of touch. At the very least I think he would have left the Jedi order like Count Dooku, another disillusioned Master.

[Assistant] It's really hard to say because Sidious was close to Anakin from his first day on Coruscant.  Anything that he did after that could have been influenced by Sidious.  Palpatine was able to cloud Yoda's connection to the force, so it is probable that he did the same with Anakin. For instance he could have given him the nightmares about his mother. which led to the first evil act Anakin committed.


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

[User]
[Star Wars] Did Vader get a promotion or something between Episode IV and Episode V?

Never really noticed this before my most recent rewatch of the ~~films~~ historical holocrons but Vader seems to take a lot more shit from Imperial officers in ANH. I always assumed Vader was basically 'second in command' since Episode III and he seems that way! ...except in ANH.

What's up with the empire's organizational structure? Are there imperial SBUs and Vader is some kind of mr. dark side consultant? Or has he basically just been the emperor's mailboy until everyone above him blew up in the death star?

[Assistant]
Tarkin and Vader had a... strange relationship. Tarkin's officers (the ones you see giving Vader shit) took it as a sign of submission from Vader, as opposed to respect, so they were quite keen on boarding the (apparent) chide train.

Also, on a related note, the Emperor kept the Empire's command structure deliberately obscure and confusing. It was clear Grand Moffs were big on the chain, but how they relate to Lord Vader or any other rank outside of sector control wasn't clear at all.


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

[User] ELI5 Why do we , and nearly all animals and birds have two nostrils ?

[Assistant]
A) Bilateral symetry caught on very early in animal evolution, so most external shapes are reflected on animal bodies.

B) There is little to no selective pressure for a more complex structure that would create more nostrils.


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

[User] eli5- Do brain cells (Neurons) divide?

[Assistant]
For the most part no.

Theyre produced originally by a stem cell, that divides into another stem cell and a precursor cell.  That neuron precursor gets to where it needs to be and then turns itself into a neuron.  Once this specialization is complete, the neuron cant replicate itself.

Theres a lot of production and culling of neurons when youre an infant, and then the stem cells are mostly deactivated.  The neurons cant replace themselves, and so the brain has very limited repair capacity.

The stem cells are deactivated so that they dont go nuts later and grow a big tumor.  Figuring out how to *safely* reactivate them in a controlled manner is something of a holy grail in bioscience.


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

[User]
CMV: Gender roles aren't socially constructed, they're a result of sexual selection.

I was listening to a podcast about Rojava when one of the female fighters started talking about what was basically feminist theory. She basically said that gender roles were socially constructed by men at the dawn of civilization to oppress women, which I dont really understand. It seems pretty obvious to me that its part of our nature, but maybe theres something Im missing?

In primates (and most mammals in general) males are the indiscriminate sex while females are the selective sex, because males produce sperm consistently at a low energetic cost whereas females produce a limited number of eggs only during certain times and at a higher energetic cost. This means it increases fitness most for men to have as many mates as possible since... they can.... while it benefits female fitness most to select the fittest possible mates in order to give their limited offspring the best chance of survival and reproduction. Males compete with one another for attention of selective females, and therefore more aggressive and dominant males are selected for. Men select for women who are more passive and emotionally sensitive because it makes them more effective at rearing children. Since men are more dominant and aggressive and women more sensitive it kind of follows that men would of course end up being the dominant sex. The sexual strategies themselves are also selected for which is why theres a pretty pervasive social more against women being promiscuous while men are generally lauded for having more sex.

[Assistant] The fact that they are socially constructed follows immediately from the observation that gender roles vary from time to time and from society to society. If they were part of our nature, then they wouldn't vary on such short time scales, and certainly not do so based on social constructs.


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[User]
How does the body cope with the presence of heavy metals in the circulation?

When I did my Osteopathy undergraduate degree many years ago, I recall learning that molecules with a molecular mass greater than six kilo-Daltons could not pass through the basement membrane of the kidney, which meant that heavy metals such as mercury and lead (and other nasties such as DDT) could not be excreted, and were consequently stored in the liver until death. Yet, in the 19th century, hatters were driven mad by mercury. (Hence, the behaviour of the Mad Hatter in 'Alice in Wonderland.'). For this to happen, I assume at least some of the mercury must have not been stored but have been free-floating in the circulation and made its way to the brain. Can anyone throw some light on this?

[Assistant]
6 kilodaltons is far, far greater than the atomic mass of any element. Mercury has an atomic mass of 200.6, lead 207.2 (note that one dalton is one atomic mass unit). DDT also falls far below that range, weighing in at 354.5. 6 kilodaltons is in marcromolecular range, which includes things like proteins and DNA.

The reason why heavy metals stick around in the body is because they form very stable coordination complexes with proteins (more specifically, with the amino acid residues in proteins). Mercury in particular forms very stable complexes with sulfur and selenium, which are found in cysteine and selenocysteine respectively. Once it gets in the body, it distributes itself throughout the body and sticks to these proteins. That doesn't mean that it stays in the body forever, though. It does slowly get excreted by the body over time, but this is a slow process.


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[User]
CMV: I think earth hour is dumb and useless

I would expect one hour in a year to be useless in fixing polution.shutting off the lights is useless imo because electric energy can be obtained in a clean way, whereas burning fossil fuels is playing a bigger role in environmental damage, including from extraction. It's a story simmilar to that of reducing the fatty foods intake to not gain weight, where the science shows that fat accumulates from sugar aswell. And so there are many products advocating low fat whilst having a ton of sweetners.so why discredit electricity with the earth hour,when there are so many successfull examples of it being a clean energy resource in the nordic countries for example.

[Assistant] The thing with the Earth Hour is not about fixing pollution by not spending energy for an hour, it is a cry to everyone who can do something about it. It is a way of showing people what it would when all exhaustible resources are gone. Look at it as a symbol, not a means to an end.


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[User] How did we ever discover what the speed of light is?

[Assistant] First attempt was by Gallileo who tried to open lanterns with his assistant really fast on adjacent hilltops. That did not work. The first successful measurement was from Roemer, who realized that the eclipses of Jupiter's moons appeared at different times depending on where Jupiter was relative to Earth. The first accurate measurement was by Fizeau, who repeated Gallileo's experiment with better equipment, sending a beam of light through a notch in a spinning cog, off a distant mirror, and back through the notch in the cog. If the cog was spinning fast enough it would block the reflection, and you can measure the speed of light based on the speed of the cog.


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[User]
ELI5: 'Death rattles'

I mean the way, in T.V shows where a seemingly dead person exhales, does this really happen? If so, why?

[Assistant] Usually in medicine we refer to death rattle as the sound most humans make when they are close to death. They will breathe in and it sounds like a rattle due to their lungs filling with fluids. If they take that last breath of air before they die it would make the same sound if they had the rattle before death.


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[User]
CMV: Looks are just as important as personality when dating. (Maybe more?)

I hear so many people saying that you should find a partner based off of their personality and not based off of looks. I've heard people say if you judge a person off of their looks when dating then you are going to end up hating your relationship. Could that happen? Yes and it could also happen if you judged a person off of personality.

**To me** looks are a first impression, rather you want them to be or not (It is literally the first thing I see) When I date someone I want to enjoy looking at them. I have a type and even if they have the best personality in the world I most likely won't find an interest if they are not my type. When I take interest in someone because I like the way they look I still make sure they are a decent person.

As far as what personality even means.. Being nice? Being funny? Liking the same things as me??

I can still date based off of looks and have the intelligence to not form a relationship if the person is mean/rude to me or others. I can still like someone if they aren't funny. I do not care what they like to do or what they find interesting when I'm dating someone. Everyone I've dated in the past has had a fascination with anime and random fighting video games. I don't like anime or fighting games so does this mean I'm not meant to be with this person? To mean that makes no sense. Also I have never dated someone who completely enjoys everything that I find interesting and that has never caused an issue. I'm not looking for my boyfriend to be a carbon copy of me. Plus at the end of the day if you love your partner you can sometimes just do what they like to do not because you like it but because you want to make them happy.

The only thing I care about in a man is:  Is he attractive to me? Do I like him? Is he nice to me? Is he nice to himself? Is he financially stable to support himself? If the answer isn't yes to all of these questions then I'm not interested in being with them.

[Assistant]
An apt comparison Ive heard and found to be accurate:

Looks are the resume, personality is the interview.

So sure, looks will help land you the interview, but if you bomb the interview, you wont get the job.

So if your goal is landing a long term relationship, personality is more important than looks.

Looks might get you lots of interviews, but if you dont have a good interview (personality) nothing is going to stick.


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[User] [Legend of Zelda] So I'm the first male born of the gerudo tribe in a hundred years or whatever, but it turns out the previous guy is not only still alive, but a godlike immortal of immeasurable power bent on conquering the neighboring kingdom. So, like, do I get to be king or what?

[Assistant]
I have to go with what the other guy said. Kick his ass. Buy do it because that's what's best for your people.

Maybe start wearing green, too. It's a good color. Anyway, there's a sword in this temple that should help you out when you actually go on a quest to fight the dude.


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

[User]
[Star Wars] If Admiral Thrawn were to fight the US, would he be more interested in a Ken Burns documentary, or our MCU/The Office/Friends type media?

Bonus; Which documentary would be his favorite? (I think the Civil War)

[Assistant]
I think our music would be more telling than any visual media.

Hed learn that the social outcasts, the despised minorities are the ones more experimental, perhaps more emotional and unpredictable.  While those in established social power arent risk takers and value conformity.


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[User]
If there was a planet that lied in the exact same orbit of the earth but on the other side, would we have any way of detecting it?

The sun would be in the way of the object always. This question implies that we can only make observations & measurements from Earth or Earth orbitting satelites (no spacecraft that have moved out of Earth's normal orbitting path).

[Assistant] We'd be able to see it at certain times of the year because Earth's orbit isn't perfectly circular. It would also be impossible to send spacecraft to Mars and Venus the way we do because the gravity of that planet would interfere.


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[User] [Pacific Rim] How and why does a Jaeger need two pilots?

[Assistant] Because they're stupidly huge and the neural link would completely overwhelm a single person. Like how a modern computer has multiple cores instead of one big one, or how a Titan from 40k requires a crew in addition to a hard-linked Princeps.


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

[User]
[Monsters Inc] How did they power the first ever door?

For anyone who is unfamiliar with the film Monsters Inc, It's based in some dimension where monsters are as technically advanced as human's although their electrical system is powered by childrens screams.

To obtain children's screams monsters go through doors into the human world to scare children.

These doors must be powered to work though...

So my question, how did they power the first ever door to obtain screams?....

[Assistant] It could be that they had other sources of power but because children's screams are a clean, efficient and potentially limitless source of energy they moved to adopt it across their entire society. After all, there is no reason to pollute if renewable energy is easily available.


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[User] What two creatures are most closely related genetically, but look the most different physically?

[Assistant]
This is a little bit of a cheeky approach to your question: the thing most genetically similar to any organism is itself (or its clone/identical twin). A caterpillar is genetically identical to the butterfly it will become, but is vastly different physically. The same goes for any animal with metamorphosis: frogs, jellyfish, crabs, flies, starfish, etc.

Another, more serious answer is tunicates (also known as sea squirts) are the most closely related creatures to vertebrates, but have almost no recognizable "vertebrate" characteristics. They barely have a nervous system, let alone a face.


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[User]
ELI5: The functional differences between cruisers, destroyers, frigates, corvettes, battlecruisers, battleships, and dreadnoughts.

I believe this was asked around two years ago, but I was still confused even after reading it. Here's what I think I understand:

* Dreadnoughts, which I think includes the German Bismark from WWI, were spiritually succeeded by battleships in WWII. In both cases, these ships were used to bombard land-based installations or garrisons. However, because they only were able to use shells, and with the advent of the aircraft carrier, the battleship became obsolete, as an aircraft carrier could do pretty much everything a battleship did but better.

* Destroyers are fast. They also are primarily used to protect allied ships - so in other words, they mostly go after submarines and aircraft. They've also been recently been able to use guided missiles - hence the "G" in DDG - alongside the AEGIS fire control system to track many potential targets at the same time.

* Cruisers are currently being replaced with destroyers. Cruisers are mainly used to fire missiles, but since the AEGIS system enabled destroyers to use missiles efficiently, cruisers are being phased out.

* Battlecruisers are battleships with weaker armor but better agility.

* Frigates aid merchant ships, and maybe amphibious assault crafts.

* Corvettes are pretty much a spiritual predecessor to Littoral Combat Ships (LCS).

Is any of this right?

[Assistant]
1. "Dreadnaughts" are a type of battleship. Namely, those patterned after *HMS Dreadnaught*. These are all-big-gun ships. In that they carry a single set of large caliber guns in turrets that can freely traverse through a wide range of motion. Pre-Dreadnaughts generally carried a mixed battery of large guns, in less flexible mountings. The Dreadnaught-style won out because by the 19-teens naval artillery was accurate enough that an all-big-gun ship could expect to kill a mixed-guns ship before the older ship could bring it's smaller guns into range.

2. Destroyers evolved from Torpedo Boat Destroyers.  The invention of the powered torpedo was a **big deal** in naval strategy. It meant a small, cheap, torpedo boat was now a threat to a big, expensive capital ship. Destroyers were designed as a fast type of ship with many smaller guns that could effectively kill torpedo boats before they could reach the big ships. They stayed in service after the torpedo boat era because of their usefulness as scouts, escorts, and anti-submarine/aircraft platforms.

3. Cruisers were originally exactly what their name says. A ship designed for long cruises. Big enough to operate independently far from home, and small enough not be super expensive like a battleship. They were your go-to ship for enforcing your policies against local bad-actors if you were a naval power of the 1late 19th and early 20th century. In the late 20th century cruisers and destroyers sort of melded together and differences between them now are basically name only. Destroyers got bigger and more capable, and big-gun cruisers became obsolete so these days "cruiser" just means "big destroyer."

4. Basically spot on. Battlecruisers were envisioned as a big-gun combatant that could keep pace with cruiser squadrons. They sacrificed armor for guns. Fast battleships basically made them obsolete by the 1940s, but they lived on a while as good platforms to cram a lot of AA guns on.

5. Modern frigates are basically smaller, less capable destroyers and are generally considered the smallest ships classified as "major surface combatants." They have a long history back to the sailing era when a frigate was the smallest of the big warships. Not sturdy enough to stand in the line, but big enough to operate independently and overpower any merchant or pirate. Basically the "cruiser" of the age of sail.

6. Corvettes are about the smallest warship that is a warship rather than a patrol boat. They generally mount very limited weapon systems, have a small crew, limited endurance, and are expected to engage primarily in littoral combat. They are a good option if your naval ambitions are limited to defense of your immediate local vicinity. Enough range and firepower to be threatening, cheap enough for smaller navies to have a bunch of them.


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[User] ELI5 - Why does a stressful day at work make you both mentally and physically exhausted?

[Assistant] The brain requires energy to work just like your muscles do, it actually uses more energy than any other organ, using up to 20 percent of the body's total. A stressful day at work is going to result in long periods of ~~high~~ brain activity which is going to drain your body's energy as a whole.


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[User]
Does electricity flow three dimensionally?

I hope that title does my question justice.

When electricity moves it takes the path of least resistance in a straightish line.

Is there ever an instance where it doesnt go from point A to B and just exsists in a space? Conceptually like a ball of lightning I guess.

[Assistant]
The word "electricity" has several meanings. Assuming that you meant "electric current":

Electric current doesn't take the path of least resistance. It takes all the possible paths, but most of it goes through the path of least resistance, a bit less through a path that is a bit more resistant etc.

Electric current is the flow of charged particles. It is possible that a charged particle doesn't go anywhere, but then it isn't electric current. It is possible to have a body that is electrically charged but it isn't electric current.


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[User] From how high up would an ant have to fall from for the impact of landing to kill it?

[Assistant]
The terminal velocity of an ant (the fastest it can fall (on Earth!), due to the interaction of wind resistance and their weight) is insufficient to harm it, so it can fall a theoretically "unlimited" distance.

I'll google the references in a sec and edit this.


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[User]
ELI5: What's the difference between one day (single use) contact lenses and regular lenses?

What makes the single uses lenses single use. Why can they not be used multiple times like other contact lenses?

[Assistant]
One day lenses are much thinner and less durable, however since you wear a new pair every day they're usually more sanitary, can't develop buildup that can scratch your eyes, and generally easier for the wearer.

Biweeklys and monthlys are much sturdier, but degrade over the lifespan of the lens. They also require a lot more care than daylies. You're supposed to rinse them for 5 seconds on each side with solution and let them sit in the contact solution for 8 hours, which can be a lot of work. Most people I've heard don't rinse their contacts, just soak them.

Also, everyone's eyes work differently - some people can use the biweeklys for over a month, while other people's contacts degrade quicker. This can lead to either just living with worse eyesight or quicker replacement. Wearing contacts longer than their recommended use period can cause microscratches on the cornea from tiny amounts of buildup. It can be done, of course, but it isn't great for the eye.


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

[User]
Why can't we replace hearts and lungs by pumping oxygenated blood though people?

 Like they do with bypass surgery.

*Edit* In cases where people are waiting for new organs and such. Why can't it be a long term solution if a replacement isn't available immediately.

[Assistant]
I took a master's in biomedical engineering and one of our professors who taught blood compatibility had actually worked on a lot of the early heart and lung machines. The two organs are indeed usually replaced together because the new artificial lung needs a good pressure difference to drive the blood through that you wouldn't want the patient's heart to have to maintain.

He told us about the detrimental effects of the systems and I'll try to summarize. One is that the pumps lyse ("pop") the red blood cells. Another is platelet ("scab") accumulation on the device. Basically, the only thing blood won't try to scab up on is immunocompatible flesh.

These problems can be mitigated by constant fresh blood infusion and swapping out the machine, but infection is also a constant risk. The devices he worked on were used to treat acute, but not chronic, lung failure while the lungs would heal to take the job back over. IIRC, roughly one week.


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

[User]
[Harry Potter] What if you are afraid of success? What would a Boggart look like in that case?

I have achievemephobia, a fear of being successful.

What would a Boggart look like if I met one?

[Assistant]
Well we know what a fear of failure looks like \- Hermione's boggart was an image of Professor McGonagall informing her that she'd failed her tests.

So we can definitely flip that \- if your fear is success, you'd see your boss offering you a huge promotion, or a professor commending you on a kickass term paper, or whatever form of success gives you the worst anxiety.


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[User]
ELI5: why do some trucks have a pair of wheels that's a bit off the ground?

what purpose does that serve? and I don't think it's necessarily because of the risk of tipping over, because some of these trucks are quite long, and the risk of tipping is very low.

[Assistant]
They do touch the ground, once they are heavy enough, they need to be on the ground to relieve stress on the other axles.

They are then raised when going around corners/bends so that they don't drag.

They are like the raised axles on a transport truck.


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[User]
Advisor is leaving, but hasn't told me

My PhD advisor is switching schools, but hasn't told me yet. I know about it because my lab mate told me. This upcoming Fall semester is her last semester at my school.

I am wondering 1) what does this mean for my phd and 2) why she hasn't told me.

I am entering my 5th year. I am planning to propose in the Fall and defend in the Spring. I still need to finish up two smallish projects, but the vast majority of my research is completed. In terms of writing, the bulk of that is also done, but I still need to write about the things I've done over this past summer and the small projects between now and graduation. Of the other students in our group, one is entering his 2nd year, and the other is entering his 4th year. It would make sense to tell them right away (although I don't know if the 2nd year has been told) because they will likely move with her.

My main concern is - can my advisor still be my dissertation chair if she leaves the university? I am hoping that the reason my advisor has left me in the dark is because I am so close to graduation, and she knows that the obvious plan for me is to just stay at the current school, work remotely with her for the last semester, and her fly back in for my defense. I don't really know if this is possible, though, and I don't want to ask anyone. I don't want to ask because this is apparently very confidential (my lab mate assumed I knew, and when he found out I didn't know he asked me several times to "pretend to be surprised when she tells you" and to keep it confidential - not even to tell our other lab mates). If I go around asking administrative people about this, it will definitely raise some red flags depending on who knows and who doesn't know. I'm a little worried about asking our graduate school itself because it might raise a red flag. The only information about this in our catalog is:

> Dissertations are chaired by graduate faculty and are selected by agreement between the student and the faculty member. A doctoral student may select  only one faculty member as chair of the committee.

Those sentences specifically say graduate *faculty*. How far can that be stretched? Could my advisor stay on as adjunct faculty and chair my committee?

I don't when this decision was made. My lab mate only told me yesterday. I was so surprised that I didn't even think to ask him how long he has known about it. It is a very big deal though because my advisor has been at the school for over 25 years, is a full professor, served as associate dean for a year, and oversees the I/UCRC at our school. The new school is definitely a move up the ladder, but I get the feeling that some department politics are also a motivation.

I have no intention of moving schools with her (it would mean moving states away), mostly because of personal life reasons. However, I've been working with her since I was an undergrad so I absolutely want her to chair my committee. It would feel so wrong to see someone's name as my advisor on my CV after all of this is done.

Does anyone have experience with this? Any thoughts, opinions, etc on what my options will be or why I haven't been told?

[Assistant] If you'll be less than a semester away from defending when your advisor leaves, and won't need any physical equipment which'd become unavailable to you due to her move, you should be able to finish quite normally and without moving. You'll most likely formally get a new chair of committee, but your advisor will stay on your committee and take main part in correcting your thesis, and attend your defense or follow it through videochat such as Skype, and you can keep calling her your PhD advisor in your CV and everything forever.


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

[User] ELI5: Why does color affect heat absorption?

[Assistant]
It's not color that affect heat absorption. It's the physical propriety of material that absorb different wavelenght of light. So if a material absord all visible wavelength of light it will appear black because it doesn't reflect back light into our eyes.

Alternatively, something white is made of something that reflect all the visible light back so we see the color white.

Something that absorb more wavelength will absorb more energy from that light, which will become heat.


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[User] ELI5: Why do we pick scabs?

[Assistant] For the same reason we might mindlessly pick at some dried glue on our hand--our subconscious mind sees it as something foreign that doesn't belong on our body. Of course, scabs are part of us (at least temporarily), and they're critical for wound healing, which is why the picking stops when our conscious mind kicks in. But it isn't entirely in our heads: The presence of histamines in scabs can make them feel itchy.


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[User]
How do you transform sound into radio waves?

If my understanding of sound is correct, the pitch is determined by the frequency of the sound.
And radio waves are determined by a certain frequency of the wave itself...
So how are we able to transform the frequency of the sound into radio frequencies, and transform it back while still getting the correct pitch?

[Assistant]
Sound waves travel from a person's voice to a microphone.  A diaphragm, attatched to a metal coil, vibrates and produces electrical signals.  The sound is now an electrical signal.

Then, the electrical signal is converted into radio waves.

There are two main technologies for turning sound waves into radio waves: AM and FM.

AM, or Amplitude Modulation, works by modulating the amplitude "power" of the radio wave in response to the peaks and valleys of the sound wave.

FM, or Frequency Modulation, combines two waves: the carrier and the sideband.  One wave has a constant frequency.  The other wave hovers around the constant frequency, but actually changes its wavelength in response to the peaks and valleys of the sound wave.

 en.m.wikipedia.org/wiki/Frequency_modulation#/image/File:Amfm3-en-de.gif  A great animation.

The waves then reach your radio set, where they are converted to electrical signals, which are in turn converted into sound by the speakers.


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

[User]
[Star Trek Voyager] Why is Harry Kim an ensign for so long?

Ensign Kim is considered a senior officer for meetings, he's bridge staff, and he eventually commands the night watch. So why isn't he promoted?

One reason I thought of is that they have to maintain a balance of ranks, but there were other promotions (like Tuvok) and a demotion *to* ensign (Tom Paris), which would seem to open up a lieutenant position on the bridge.

[Assistant]
*Voyager*, though taking casualties on its journey, presumably did not lose enough crew to warrant promoting people outside their positions. With nobody to replace them from their lower ranks, Janeway would be faced with twelve Lieutenant Commanders and not enough Ensigns beneath them- let alone non-commissioned crew.

Harry did have senior ranking and was given the proper respect due to his experience, but could not be moved out of his position- the crew was already made up and sorted. Perhaps things could change as crew members were lost, but the bridge crew was mostly safe through the journey and thus did not allow for promotions very often. However, given his specific branch, it's likely that Ops simply did not have many openings and was a stagnant line.


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

[User]
Why do skydivers have a greater terminal velocity when wearing lead weight belts?

My brother and I have to wear lead to keep up with heavier people. Does this agree with Galileo's findings?

[Assistant] For a quadratic drag force, your terminal velocity is proportional to the square root of your weight. If everything else is the same, an object with a higher mass will have a higher terminal velocity.


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[User] ELI5: Is the gift of genius a random phenomenon? If not, what is the purpose?

[Assistant]
Unless you're a believer that there's some sort of Grand Engineer out there that is dictating or influencing our lives and existence according to some aim, not everything has a "purpose".

Some people are mentally challenged and can't use their brains in the same way as the norm, and some people are brilliant and can use their brains in ways that exceed the norm. It's the way our genetics works, where sometimes we get over-expressed traits such as intelligence and other times they're under-expressed. And the environment the kid is raised in contributes greatly as well. So it's somewhat random, but the odds that two highly intelligent people will have a smart kid is higher than the odds that two normal-intelligent parents will.

Sometimes, as in an idiot savant, those two extremes are combined in one person.


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

[User]
ELI5: How does antivirus software get created?

With so many viruses and malware out there that can do a variety of harmful effects to your computer (up to corrupting your OS), how do antivirus companies like McAffee and Symantec track and effectively create software to combat these viruses?

[Assistant]
> antivirus companies like **McAffee and Symantec** track and effectively create software to combat

They don't.

More seriously though... AV vendors use a handful of tricks to try to detect and combat malicious software. nothing is perfect, though, they just do their best. Some common techniques:

1. blacklists - this is the most rudimentary thing you can do and is the backbone of essentially all modern anti virus software. If you know that a piece of software is bad, you save a signature of it so that the next time you see it you know it's bad and can stop it. the companies have teams dedicated to analyzing software and creating signatures and constantly update their databases.

2. heuristics - this is more sophisticated, you have your software inspect and examine a piece of unknown software in order to automatically analyze what it does, and you make an educated guess based on it. AV usually have options to dial the heuristics up or down since more stringent heuristics detection means more hits means better protection means more false positives.

3. sometimes an AV will just let an unknown software actually run in an isolated sandbox then watch what it does to see if it does anything bad.

4. if you *really* want to be secure, you can use a whitelist system, where you only allow anything in your database. anything unknown gets blocked. this would be a huge PITA to use and is exceedingly rare, and it's not really traditionally part of an AV either.


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

[User] [Dark Souls] If many of the bosses are undead like the PC, what makes them permanently die as opposed to just being revived at a bonfire?

[Assistant]
Very few of the bosses you fight are actually undead. A lot of them are demons or dragons or Gods. They aren't branded with the Dark Sign and, consequently, have no connection to the bonfires. Some of the ones that actually are undead don't come back to life because you've stolen their souls or just don't have the will to go on.

There's also the possibility that they do revive, just in a different timeline. With the fading of the flame, the flow of time in Lordran becomes more convoluted as timelines intersect and separate.


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

[User]
CMV: Gender dysphoria is a mental illness

I should set clear that i really want social inclusion of all kinds of people (homosexuals, blacks, poor people, transgenders, etc), and my view doesn't necessarily mean that i am against transgenderism.

By definition gender disphoria is a mental illness and that's final. That said, it doesn't mean it actually is a mental illness, for the definition may be changed or not be accurate.

However, I don't see any other way to categorise the need to change gender other than a mental illness. If you don't feel aligned with your body, it would be wiser to at least try therapy and medication before undergoing a violent surgery / hormonal treatments (the issue could be solved before doing such intrusive intervention, and if therapy didn't work, then they could try the surgery and hormones).

It also seems to be a way to mask the real issue (identity disorders) but not treating the root cause of the problem, and that will lead to anxiety, depression, stress, confusion in some cases.

[Assistant]
Are you certain gender dysphoria has *only* a psychological cause? If it were one's dysphoria were influenced by biology, would you still call it a mental illness? Because it would make sense that if gender identity is, in part, biological then gender dysphoria would also, in part, be biological. Would it not?

At the very least, if we don't know the nature of gender dysphoria then it might be reckless to just say it's "a mental illness and that's final".


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

[User]
[Fictional training] What sort of training would various characters do?

I mean, how do they keep so intense? People like the Batfamily, Assassins Creed, various comic peak humans and the like. Super powered heroes and villains too. What do these people do to train? Do they? What do they even eat, if they do? When do they have time to do any of this?

[Assistant]
General fitness and combat training for most of them.  Even people with relatively busy schedules can make time for an hour or two at the gym.  Cardio, strength, flexibility, and speed.  You can tailor your workout to the kind of performance you need.

Full-time heroes, like the Avengers, probably train more or less all the time when they're not out saving the world.  Obstacle courses, group tactics, etc. Would be similar to a military unit.


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

[User] Are there any legitimate medical conditions that make it difficult to lose weight, even on very low calorie diets? Doesn't that violate the laws of physics?

[Assistant]
There are many, many cases when people have no idea how much they actually do eat. Or, when they do, they are not honest.

That being said, it is possible that the individual is honest. In that case, there are a number of variables:

Not everyone absorbs nutrients at the same level of efficiency. Some people absorb better than others.

Not everyone has their basal metabolism at the same level. Some people burn more calories while resting, others burn less. This remains true even for people weighing the same. It depends on the body composition, age, gender, fitness, various medical conditions, etc.

A young, muscular, lean, fit man will burn a lot of calories just sitting down. An old, fat, out of shape woman will burn much less - even though she weighs the same weight like the young male athlete.

The same young, muscular athlete will burn more or less calories while sitting down, depending on the levels of thyroid hormones in his body - this is just one example out of so many.

EDIT: The nice little charts you see online, that tell you how many calories you're supposed to burn, based on weight and age, are just guidelines. There are many, many other factors that are pretty important.


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

[User]
Ethics of lucid dream sex

TW: mention of sexual violence, cheating, murder, etc.

Bit of a weird one, but hear me out. I have been having lucid dreams semi regularly recently and I always seem to try to have sex in every dream. Idk why, maybe Im just horny. I am in a relationship but it is long distance and I barely ever get to have sex with her. Recently I had sex with another woman in a dream that wasnt my girlfriend. Its happened a few times. In fact I feel like I have sex with others more than with my gf. Maybe its because I know in real life me and my gf have sex but in a lucid dream I get to have sex with anyone I want.

Also let me just say this woman was not a real person she was a random girl I invented at the time.

Now in the lucid dreams I am obviously 100% conscious and in control of my actions. I am also in control of what I want to happen in the dream. The situations also feel very much like real life to me at the time.

It lead me to think of this ethical dilemma. I cannot justify as to why this shouldnt count as cheating. Just because the person I had sex with was not real doesnt change anything about the actions from my side. How is it tangibly different to real life cheating? And to me it was like real life when I was in the dream.

But then again, would having sex with a sex doll count as cheating? Im thinking no. Would fantasising about other women count as cheating? Its obviously not ideal in a relationship but again not cheating.

This also lead to some other questions about lucid dreaming ethics. Like is it unethical to commit rape or other sexual violence in a lucid dream? What about murder?

I mean in both scenarios there is no victim. It would be no different to a fantasy. At the end of the day I think what makes rape and murder unethical is the presence of a victim. I think I have the belief that thoughts that happen inside your own head, are not backed up by actions, and that never leave your head (ie saying them OutLoud, telling people, etc.) cannot be unethical. Can thoughts be unethical if they dont have real actions? And are actions in lucid dreams comparable to thoughts since they both happen inside your head and not in real life?

Just wondered everyones thoughts and if theres any philosophical thinking that has already gone on in this area. Basically help me figure out if I cheated on my gf in a lucid dream

[Assistant]
It seems you more or less worked this out by yourself, what happens in lucid dreams isn't real, you're just imagining shit, so nothing in there matters in of itself.

The relevant thing you should be concerned with is how the things you imagine can form dispositions towards actual actions. If you constantly fantasise about fucking other women, will this have some influence on you actually doing this? It seems plausible. So we shouldn't be concerned about how the stuff bouncing around in our head for its own sake, for the sake of us wronging dream people or whatever other nonsense, but how what we imagine can influence us in the waking world.


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

[User] [LOtR] Why didn't Sauramon keep any Uruk-hai to defend Isenguard during the battle for Helm's Deep?

[Assistant] He actually kept a small garrison of Orcs to keep making Uruk-hai and prevent squatters/bandits. In his arrogance though, he never expected the Ents to attack and never imagined Rohan would survive his army's onslaught at Helms Deep. So he simply sent them all to fight Theoden.


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

[User] ELI5: How can a country like Venezuela, with more oil than Saudi Arabia be broke?

[Assistant]
Mostly poor planning.

Venezuela's government wanted to help the poor, so they put a lot of money into social programs.
This included money that was supposed to be going to the national oil company that makes up most of their income.

When the oil company people protested, Hugo Chavez responded by firing a bunch of them, and replacing them with people loyal to himself.

So, since like 2006, the amount of oil Venezuela has been producing has been decreasing.

On top of that, the government decided to fight an economic recession by setting a price that everything must be sold at, along with how much people need to be paid.

This price was so low that it meant that companies couldn't afford to sell that much, so people with more money (from the higher pay) paid more for the stuff that was there, driving prices up.  This kept occurring, and the resulting inflation broke most structure in the nation.

Since Venezuela's currency became worthless, and the amount of income in other bills dropped with the loss of oil, the government has needed to step in and keep paying for food and stuff for the poor.  What this meant though is that the government has just been pushing the problem down the road, rather than solving it.

Which, after years of trying to deal with the problem in front of their face, has crashed their economy entirely.


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

[User]
ELI5: What is the closest thing we have to a 100% efficiency machine?

Apologies if this doesn't fit in the sub, first post

I know that machines can't have 100% efficiency, but what is exactly do we have that actually comes very close to a perfect machine?

[Assistant]
The highest efficiency machine we can produce is one that produces heat, so, a space heater. Those actually are 100% efficient at their goal, because even the energy turned into other forms like sound, eventually make their way to random molecular motion, aka, heat.

As for heat engines, where we want to make motion. The efficiency of those machines is capped by the Carnot cycle. The Carnot cycle efficiency is determined by the temperature difference between the hot side, and the cold side, so theoretically, you can make it arbitrarily high, but in practice, we don't get quite that high (~60%).


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

[User] ELI5: How can human smugglers illegally ship migrants to a different country? Can any ship just dock at any harbour and unload "goods"?

[Assistant] A ship can deliver cargo anywhere if they have approved customs paperwork to do so. While there, they can sneak something extra off the boat, or include something extra in the container with the cargo.


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

[User]
ELI5: Why it's supposed to massage the face cream using a circular motion? ( often upward motion too)

.. it's not absorbed well if it's massaged.. let's say horizontally?

[Assistant]
Or else it gets the hose again.

Horizontal or vertical massage is less likely to spread evenly, also the massaging itself is beneficial (potentially more beneficial than the cream, some studies have suggested its daily massage thay actually helps the skin long term not the cream at all).


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

[User]
ELI5: Why does your body discard excess protein, but will cling to every last bit of fat that it consumes?

If you eat more than a certain amount of protein per hour, your body rejects whatever it cannot absorb. Why is there no "threshold" for the amount of fat you can consume in an hour? You seem to just hold on to every bit of fat you eat. Can someone set me straight on this?

[Assistant]
You don't get fat from eating fat.  You get fat from eating more calories than you expend (plus a dozen other factors).  Fat is pretty calorie dense, so it does help power the body and, of course, add fat to it.  But it isn't that you eat fat and it passes unchanged into your hips.

The body adds fat every chance it gets and only begrudgingly sheds it because we *used* to live in a world where you could never be sure of eating regularly, so you packed on fat in times of plenty so you'd have an extra source of energy when times were bad.


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

[User]
[Harry Potter] What was the Soviet Union's wizarding community like?

It is implied the muggle governments are aware of their wizarding counterparts. However, the existence of a sub-group of humans who are born with abilities far beyond those of normal humans seems like something which would not be tolerated by communist ideology. How did the Soviet Union deal with its wizarding community? Did they hunt down wizards and witches? Or did they just leave them alone?

[Assistant]
Official Wizard policy is that, should the risks of revealing the existence of magic be too great, then they simply will not cooperate with their Muggle counterparts.

The Magical Congress of the United States of America (MACUSA) notably does *not* cooperate with the federal government due to the founding of the Magical Congress being a direct result of the Salem Witch Trials, and prior to their using the Woolworths building in New York City, they had to abandon four other governmental headquarters due to fear of No-Majes. They also refused to outlaw alcohol when the federal government brought in Prohobition because "We have enough to deal with".

If anything, the Russian Magical Community isolated themselves after the Red October due to fear of persecution from the Communist government.


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

[User]
ELI5: If a can of pop can have 9 tea spoons of sugar in it, then why would a cup of tea with 4 sugars in make me feel sick, yet I could chug a litre of pop and feel fine?

Is there something done with the sugar to stop it making you nausiated?

[Assistant] Carbonation. The co2 becomes carbolic acid and neutralizes the sweetness of the sugar. Soda is acid enough to damage the enamel of your teeth, and sweet enough to give you a whole host of other problems. And yet, since it's both at the same time, it's perceived as neither. Some sodas of course also use orthophosphoric acid and citric acid as part of the recipe.


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

[User]
ELI5 Does a dislike of warm weather has anything to do with the person's weight?

I am overweight and I hate any weather above 25C. I remember preferring spring,  autumn and winter even when I was a child and not overweight.

[Assistant] It has more to do with your comfort than weight because you are likely associating warmer weather with discomforts such as: more revealing clothing, sweat, more difficulty at exerting energy. 25 degrees is a nice summer weather and for most people, unless you are on the beach, anything higher than that would be generally associated with discomfort. So yes and no.


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

[User]
ELI5: What is "non negotiable bearer bonds" and what would Hans Gruber have been able to to with all those bearer bonds?

I was born in early 2000's and have not heard yet in any form or type. Also I wonder how much would it worth in today's currency?

[Assistant]
Bearer bonds are "payable to bearer upon demand". So person A buys a $1000 bearer bond from an issuer (company, railroad, etc).  Person A owes person B $1000 and gives them the bond as payment. Person B wants some guns/drugs/whatever and Person C sells them the whatever in exchange for the bond.  This can go on for many transactions.  In the end, Person X now has the bond and wants cash.  They can take it to their bank and exchange it for cash and the bank gets the money back from the issuing company.  The US government caught on to drug dealers moving large amounts of money with them in the 1980's and made bearer bonds illegal to issue to stop this.   People can still cash in the existing ones, though.

TL;DR - They are a way to make cash like transactions but much harder for police to trace.  They can also have values much greater than currency so money can be more easily moved across national borders untraced, by carrying them as you travel.


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

[User] Are high frequency trading careeers "cheating" and they do not create value but just "push money around"?

[Assistant]
They add liquidity to markets, but some say they increase market volatility.  From Wikipedia:

The effects of algorithmic and high-frequency trading are the subject of ongoing research. High frequency trading causes regulatory concerns as a contributor to market fragility.[52]Regulators claim these practices contributed to volatility in the May 6, 2010 Flash Crash[58]and find that risk controls are much less stringent for faster trades.[16]
Members of the financial industry generally claim high-frequency trading substantially improves market liquidity,[12]narrowsbid-offer spread, lowers volatility and makes trading and investing cheaper for other market participants.


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

[User] ELI5: How can the Task Manager in Windows or Force Quit in macOS close frozen, suspended, unresponding programs instantly. What do they do different than clicking the X button in the corner?

[Assistant] They forcibly stop allocating system resources to the program, instead of politely asking the program to relinquish those resources once its finished. Its the difference between asking a drunk patron to leave the bar vs grabbing him by the collar and tossing him out the door.


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

[User]
[Freespace]What most likely happened to Earth following the destruction of the Lucifer?

Earth has been cut off from the rest of the Galaxy due to the collapse of the Jump Node caused by the destruction of the Lucifer.  Would Earth be capable of surviving with only the resources of the Sol System to maintain them?

[Assistant]
Earth actually did fairly well after the Shivan threat.

Yes limited recourses became a bit of a problem. But in terms of the essentials earth was pretty well off. There was some limited rationing of food until several thousand industrial facilities which had suddenly become obsolete were leveled or retooled towards food production.

The only tragedy is that after it was decided that the jump point would never reopen slowboats were the only way to recolonize the rest of the galaxy. It wasn't until well after the ark ships departed that the human/vasudan made Knossos gate was activated and reestablished the subspace connection with earth.


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

[User] [X-Men] If Charles Xavier had used his powers to their full extents without any limitation, how powerful would he be?

[Assistant]
He could wipe out all of mankind when attached to Cerebro, since he could literally tap into everyone's brain at once.

This is just a potential feat of his. Hard to say how actually powerful he is, since he's not really limiting himself he's just not actively going all out.


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

[User] By what mechanism does borax kill ants?

[Assistant] Borax upsets their digestive system and causes death due to dehydration and starvation. According to Jonathan Hatch ("How to Get Rid of Argentine Ants" ), dehydration and recrystallization of the boric acic lacerates the digestive system of ants and their larvae.


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

[User] [Roger Rabbit] alcohol makes Roger go bat shit nuts. But, we see other toons like Hank Hill and Rick Sanchez drinking all the time (in Ricks case, absolutely smashed!). If we assumed that Rick and Homer exist in this universe, would they react the same way, or are they more immune?

[Assistant]
They're both going for different kinds of humor. That's actually the explanation; we see a couple times that a toon's behavior is totally informed by their... for want of a better word, their routine. So some toons are the type to melt when they're embarrassed, turn completely pale when terrified, reach into pockets that weren't there before and pull out something that couldn't possibly fit in there... et cetera. And some of them aren't.

I would assume the guys you're talking about find lodgings in Cool World.


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

[User] How do flash floods happen?

[Assistant]
If you have ever had a potted plant that you forgot, or left unattended over vacation, and came back to it bone dry, then added water, you probably noticed the water didn't soak into the soil right away. Maybe you even had the water flow over the edge of the pot?

Its the same idea on a larger scale. Long periods of drying out will cause the soil to be hydrophobic until thoroughly wetted. If you have massive rains, the water doesn't soak into the ground fast enough and instead just runs down hill. A sufficiently hard rain will get you a flood.


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

[User]
[Star Wars] Why did Darth Maul survive being cut in half by a lightsaber but Snoke did not.

Snoke seems like a much more powerful Sth than Maul.

Edit: Thanks for all the answers guys, my knowledge of the extended universe is obviously lacking, it's just something that kind of bothered me.

[Assistant]
Snoke isn't a Sith. He's part of a completely different tradition, and even mocks them for being petty fools.

That being said? Maul was young, and Snoke was old and feeble. The area in which they were both bisected is also different - Maul got a swift cut right at the hips, Snoke got cut higher up, where more vital organs are.


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

[User] [Star Wars] Were the Jedi paid for their services?

[Assistant] They were paid the same way a monk is, they have funds to use, however it's not really theirs, it's more to use on whatever they are assigned to. So for example you're a jedi librarian and you're given a bit of cash, you are already provided robes food and shelter, so you don't gotta worry about that, you just use your budget to improve the library, or maybe give it to some homeless people. For the most part though, people don't like to charge the jedi, afterall the jedi are heroes and help the community alot, so the rich who already donate don't mind and the poor don't mind helping the jedi either. Other's like Ahsoka may be given some amount of money to bribe someone for  buying info and may use the leftover for a small bracelet or charm or something, but that would be frowned upon. Jedi are a minimalist society, hence why they really only own their robes and lightsabre, maybe a space ship if they're important. That's why the jedi masters in hiding kinda live in shacks. Both Obi-Wan and Yoda live in some crappy shack in the middle of nowhere because they don't value money or possessions, they just get all spiritual and they're good.  So long story short, you get paid spiritually and with training, but not monetarily.


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

[User] [Captain America: Winter Soldier] Why did HYDRA try to kill Fury when he was in a SHIELD vehicle? Wouldn't they know it was bulletproof, could fly, etc.? Why not cap him in the john?

[Assistant] That's why they came prepared to counteract all of Fury's vehicles features.  They rammed the car breaking the flight system and brought the battering ram which broke through the window, Fury barely escaped and only because he is a highly trained badass.  If they try to "cap him on the john" then they would either have to try to kill him at SHIELD HQ which is a heavily secured facility, or at his house, which would most likely have a shit load of security features and maybe an escape tunnel or 2 which seems highly likely seeing how serious he took his personal security by having a heavily armored flying car.


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

[User]
CMV: Friends is NOT funny and its Awful

I have NEVER understood why anyone finds this show funny. I was born in the 90s, so I recall my mom watching it at the time and even when I was toddling, I thought the show was totally asinine.

I have never witnessed such a vast array of unlikeable assholes as can be found on this show. Where to start? Rachel is selfish and annoying. Joey is misogynistic and stupider than a toddler. Chandlers so freaking obnoxious. Where to even start with Ross??? I think Monica and Phoebe are alright, but theyre not funny enough to carry a show.

Why do people like this!? Im pretty sure Ive also heard they NEVER had black people on the show when they lived in NEW YORK CITY, which is so deeply messed up.

Whats the deal folks? Change my mind if possible; Im not honestly sure it is!

[Assistant]
1. They wrote 6 characters who have vastly different personalities, have vast different backgrounds, and who are of equal importance to the show. They literally got paid the same amount starting from season 3.

2. They helped normalise homosexuality, as well as conversations surrounding many other social issues.

3. The fact that you hate the characters is testament to the good writing.


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

[User]
ELI5: What is an RSS Feed, and how does it work?

Hi everyone, I manage a small business and we're trying to increase our web presence. Social media, blogging, SEO and a new website- we're pretty much revamping everything. My latest project has been setting up a blog and I keep coming across RSS Feeds. What are they, what do they do? How are they helpful?

[Assistant]
An RSS feed is basically a way to easier send content to your audience.  Let's say you have a blog you update every 2-3 days, but can occasionally be inconsistent on.  If you have an RSS feed (most Wordpress-like sites have this built in), people can put the link to your feed into an RSS reader (such as Feedly) and get your content automatically at a time of their choosing.  People still get your message, without simply checking your site and hoping for an update.  It doesn't just have to be type-written content either...podcasts operate the exact same way.

Does that help?


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

[User]
If an isolated system reach a microstate where it has a macroscopic velocity, doesn't it violate the law of conservation of energy?

I know this is very, very, very unlikely edge case, but let's say that an isolated system, with an incredible luck, reach a microstate where the direction of their microscopic speed synchronise, in such a way that the system has a macroscopic speed. This mean we have a E=Ec (U=0 and Ep=0 too), yet the system is isolated so it should have a E=W+Q=0. I was wondering where the mistake was in my reasonning.

[Assistant]
The mistake in your reasoning is in the process from going from a stationary system to your edge case. That macrostate can never happen, for fundamental (not probabilistic) reasons. Consider the macroscopic system as simply a gas of particles. For simplicity, we can just think of the case where all the particles have the same mass (but this argument can easily be extended for the different masses case by considering momentum conservation). Initially, there is 0 average velocity in this mess of randomly-moving particles. Now say your desired incredibly lucky state has all the particles moving in the +x direction. Do you see why there cannot be any series of collisions that takes you to this state? At the beginning, half the particles will have a negative x-velocity. To make one of these particles get a positive x-velocity, another particle has to collide with it and lose some of its own positive x-velocity. So we can never make all of the particles have positive x-velocity! The same is true in the other dimensions.

Here's a cute and more intuitive proof if we just considered elastic collisions: in this case, all collisions are time-symmetric. So, we can simply start with your end case of all the particles moving in the direction with the same speed. How on earth can a series of collisions go from this to a stationary system? Firstly, this idea already shows you that there must be some small variations in the speed or we could never leave the synchronized state. But even then, any time you try to make a particle go in the backward direction, you have to make another particle speed up in this forward direction.

tl;dr: It can't be done because momentum must be conserved and so the total net speed cannot change unless an external force influences the system, in which case EW+Q anyway.


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

[User] Can water really be broken down and used as fuel? If so, why aren't we using water as fuel for everything?

[Assistant]
We don't use water as fuel because it isn't a fuel. Hydrogen is a fuel, but you only get it by breaking water, and the energy released is necessarily less than you put in. So in this sense water/hydrogen are being used like a battery.

There are several economic reasons for restricted adoption of hydrogen storage, like the explosive risk, need to compress, metal embrittlement, and cost of fuel cells.


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

[User]
Countries that developed after political liberalization?

Are there any countries that developed after political liberalization - i.e the modern, rights-oriented democracies that we have today. China, South Korea, Russia and Singapore had either repressive dictatorships or "soft" authoritarianism. People could argue about Japan but one of the most important component of development - human capital and education- was developed prior to that. Like Germany had its infrastructure destroyed but thanks to human capital was able to spring back up. Other countries that escaped the middle income trap- Israel and Taiwan, don't fit this either because of one reason or another. Britain didn't bring much of liberal reforms (like wages/work conditions) until after significant gains from the industrial revolution and colonialism. Same can be said for USA, but I'll be looking for more recent examples preferably. What's remaining is probably countries that leveraged a scarce natural resource (OPECs, Nauru, etc), I don't know a lot about them but it doesn't seem to be the case among these either.

So, any examples?

[Assistant]
You're going to have to clarify what you mean by bit development and liberalization; neither are binary concepts, and both seem to assume a linear path of progression for all countries.

For instance, labour laws are not the same as liberalism, and in fact are a newer form of the imposition of state power.

Colonialism and trade did create wealth in both the US and Britain prior to, say, the American Revolution, but then that was true for the ancient Phonecians and Greeks.   Certainly, those societies were still mostly agrarian, and would not be developed by our standards.