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

[User]
Can a country print money to a certain degree, without it leading to inflation?

Let's say a country wants to improve its educational system.  Could it just pay the teachers higher wages, to attract more professional workers, and print money to renovate or build new schools? Would that lead to inflation?

[Assistant]
The answer is yes, but not in the way you mention.

Most economies grow over time. That growth is a deflationary force. All else being equal it pushes prices down.

That can be offset by the long-term inflationary force of money creation. So, it is possible for a country to steadily create new money with a long-run inflation rate that is close to zero.

However, kelkokelko is correct that funding things like building schools through money creation is a bad idea. In developed countries money creation is generally deal with by Central Bank. Those organizations are quasi-autonomous. The helps deal with the problem that politicians often want to reduce interest rates to increase their own short-term popularity.


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

[User]
ELI5:Why it would take you months to get in shape and 1-2 weeks to lose it.

it's really hard to build up some muscle and lose that fat around your belly , you stay on diet and work-out regularly for a long period of time. but once you stop ! it take much less time to lose what you've built.

[Assistant]
We humans were not always living in conditions of plenty. There was a time, and some still live this way, when we didn't know where our next meal would come from, or when it would be. To conteract this, our bodies have adapted in several ways to survive the lean times, and maximize our ability to make it to the next meal.

The two adaptations that are most relavent to this question is the storage of fat, and the limitation of muscle growth. Fat deposites are our bodies way of storing energy for later, when there is not enough food to survive on. Whenever your body finds itself with a surpluss of calories (like when you have that double quarter pounder with cheese) it converts some of those calories into fat, which is stored somewhere in your body, usualy under the skin where it also insulates you, to help regulate your body temp.

Muscle is expensive, in terms of calories. It costs lots of resources to build, and just as many to maintain. Muscle tissue also burns many more calories than most other tissue, even at rest. Your body will only build more muscle when it is exposed to conditions that strain the upper limits of your current muscles abilities (your work-outs). When you stop working out, your body no longer needs this expensive tissue and will divert resources away from it, allowing it to shrink, or sometimes even atrophe. This tearing down of muscle and build up of fat is much easier and, therefor, faster for your body to achieve.


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

[User]
ELI5 why General Petraeus needs to resign over this affair?

Cheating can cause problems for elected officials due to their allegiance to their constituencies, however I am at a loss as to why an individual of General Petraeus' skillset, history, and critical engagement in warfare strategy would be subject to this scrutiny.  He is not elected and does not answer to the public.  Why did he have to resign?

[Assistant]
A large reason is because the CIA doesn't want its top executive to have been black-mailed should it ever come to that over this affair.  It's almost standard practice.

Also, he was pressured to resign by the FBI, who were the initial group to find out about the affair in the first place.


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

[User]
[I Am Legend] Questions regarding the scene where Robert Neville got trapped.

Did he fall for one of his own traps?

Did the Darksiders move the mannequin or was Robert Neville just having an insane episode because it was his birthday?

Or did the Darksiders move the the mannequin and set up their own trap?

[Assistant]
The darksiders observed his trap that he used when saving max. They reverse engineered it and put it in the water. They then set the mannequin there knowing it would attract Robert.

Robert saw the mannequinn/friend in a place it had never been before. He *knew* this was *impossible* since Robert hadn't touched it. In his frightened panicked state he shot it. Investigating, he got stuck in the trap. This is one of the first hints that the darksiders are still intelligent and not mindless predators.


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

[User]
Why is existence not a predicate?

I want to understand why existence is not a predicate.

This is what I understand: Existence in English seems to work like a predicate, but for some reason it is not a predicate when it comes to logic. My understanding of predicates is that they are properties which are ascribed to something.

Help me understand.

[Assistant]
Short answer, it's because unlike other properties, it doesn't *add* anything. Compare "A blue ball" and "A blue ball that exists". The "exists" adds nothing that isn't already there, because its existence is *just* the presence of properties, in this case the property of being blue, and whatever other properties are commonly ascribed to balls.

Of course, that isn't uncontroversial, but it gives you a rough idea.


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

[User] How come we get no energy from water? Calorie-wise that is.

[Assistant]
I can answer longer if this isn't what you're looking for.

Take carbohydrates for example, there is a lot of energy stored in the carbon-carbon and carbon-hydrogen bonds. Our cells break these bonds and reform them with oxygen we breath to form CO2 and H2O molecules which are at a lower energy state.

H2O in water is already at a very low energy state and our body has no process by which to breakup H2O into even lower energy components and get calories from it.


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

[User]
ELI5: Why did the SEGA Dreamcast do so poorly?

I remember playing it at a friend's house, and it seemed just fine, and I am told it had a respectable game library?

[Assistant]
So the first strike against the Dreamcast was that SEGA had already flooded the marked over the past half decade+ with far too many half baked pieces of hardware.

The Sega Game Gear(Sega's attempt at a handheld) failed miserably because it was bulky and the battery life sucked.

Then, two major add ons for the Sega Genesis(or Mega Drive), the CD and 32x, were released, and failed miserably.

The Saturn was the next product to come out from Sega, and it too did absolutely atrociously in North America and the European Union, although it wasn't a complete failure in Japan.

So at this point, Sega's reputation is pretty poor; it's released 4 consecutive failures. It doesn't have nearly the developer support that Sony and Nintendo have either.

Then they release the Dreamcast. They go for a first to market strategy in Japan, releasing the console on Nov. 22, 1998, and it works, as the Dreamcast has strong initial sales in their domestic market. That was a two year jump on the next console(the PS2). They released in NA and EU a year later(still one year ahead of Sony), and although the launch was successful, there were several key reasons the system ended up sinking.

1. Sega had a poor reputation after the failure of their previous four attempts, especially in North America and Europe.

2. Sega chose to use a proprietary format for their discs(GD-ROM), instead of the DVDs that the Xbox and PS2 used.

3. The Dreamcast had weaker hardware than it's competitors. Being released two years early gave it a first to market advantage but all the consoles released afterwards were more powerful.

4. The Dreamcast had poor third party support. There were many gems(Shenmue why you no trilogy?!), but the Dreamcast has ~670 games while the PS2(according to Sony) has 10,000+. A huge thing was that EA Sports titles never ended up on the system. As much as NHL 2k5 is one of the greatest sports games ever, Sega's sports games have always been second fiddle to EA and the Dreamcast era was no different.

4. Dreamcast lacked big franchises to draw in users(Sonic Adventure was terrible). People had to be sold on the merits of the games being made, not on the merits of it's predecessors. The PS2 had the advantage of series like MGS and Final Fantasy. The Gamecube had a hardcore fanbase of dedicated Nintendo fans who bought the system specifically for the purpose of playing Super Mario Sunshine and Windwaker. The Xbox got lucky in that it launched with a killer app in Halo, but it was being marketed by Microsoft, the then biggest company in the world.

As soon as the PS2 launched it slaughtered the Dreamcast in sales(it was a DVD player and had more games), and then the Gamecube came out and drew all the Nintendo fans out of Sega's revenue stream, and the Xbox came and got all the hardware nerds. Things were immediately bleak. The only things Sega had going for it were a small stable of AAA titles and online play. When Xbox Live came out the entire system became redundant unless you just absolutely had to play Shenmue or Skies of Arcadia.


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

[User] ELI5: If lesbians aren't attracted to men then why are they attracted to butch women who look like men?

[Assistant]
Two reasons:

1. Confirmation bias. Two femme lesbians are less likely to be seen as a couple, so you don't notice them as much or assume they're just friends.

2. Butch is a style, but it doesn't actually stop them being women. A straight dude wouldn't want to date a man no matter how effeminate he was, it's the same for lesbians who like the butch style - the woman is still a woman and that's what lesbians like.


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

[User]
[Evangelion] How does the government/media explain the Angels to the general public?

What does the average joe living in Tokyo-3 know about the Angels? I remember it's stated that the public believe the Second Impact was caused by a meteorite. Is there a similar cover-story in place to explain the regular Angel attacks on the city?

What reasons do the Japanese government give for the fact that they have a huge fortress city which houses giant robots, who are piloted by children for the sake of fighting off weird kaiju that appear regularly to attack the same city?

[Assistant]
I think it was general knowledge that the Angels reaching the Geofront would have caused Third Impacy somehow, but the details (Second Impact, Lilith, humanity being Lilim etc.) are hidden

At the very least, we know that the Angel attacks are global news events, and the entire world was willing to expend massive resources to help in Tokyo-3s defence. Even though SEELE was pulling the strings behind the scenes, they still had to justify this massive expenditure to governments, militaries and the general public.


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

[User]
How does period life expectancy adjust when cohort life expectancy goes down?

My understanding is that when cohort life expectancy grows, period life expectancy lags because period life expectancy is measuring life expectancy of all existing cohorts, whereas life expectancy for the new, youngest cohorts would be expected to be higher.

We've just gone through a pandemic where period life expectancy declined in the US two years in a row. Presuming SARS-Cov-2 doesn't go away, and we have a new added cause of death at 2021/2022 rates, would we expect a similar downwards lag?

I'm wondering if we would expect period life expectancy to stay the same as it was in 2021, other things equal? Or would it continue to decline further?

[Assistant] Period life expectancy is a snapshot of today. Cohort is a prediction of the future. Period life expectancy would only go down further if more people died. If COVID and everything else stays constant, period life expectancy will stay constant, and cohort life expectancy will come down to match.


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

[User]
ELI5: why can't you divide by zero?

According to logic, if division is splicing a number into equal parts, dividing by zero would be 0 parts, and the result would be 0, right?

[Assistant]
Okay so say you have 10 apples.  You can put those apples into 10, 5, 2, or 1 group/s quite easily.  You could even put them into 4 groups by splitting 2 of the apples in half.  How many apples would be in those 0 groups?  How do you put 10 apples into 0 groups?

The answer is that you cannot physically put those 10 apples into evenly into 0 groups.  So the answer is undefined.


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

[User]
Why is the chemical formula for Acetic Acid written with repeated elements, rather than subscripts denoting multiple elements?

Why is it written as [**CH**3**COOH**] rather than [**C**2**H**4**O**2] or something like that? Are there other compounds with chemical formulas like that?

[Assistant]
Yeah, it's written that way to make it clear what the structure is. This form of writing formulas is common in organic chemistry just because it's more clear what exactly you're talking about.

In this case, acetic acid consists of a methyl group (CH3-) and a carboxylic acid group (-COOH), so writing it as CH3COOH makes it clear what isomer of C2H4O2 we're talking about.

Most, if not all, compounds in organic chemistry are written like this.


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

[User]
ELI5: How do bruises heal themselves?

When you get a bruise, the black and blue spot you observe is a result of burst blood vessels beneath the skin. Where does the blood go as the bruise heals? What happens to it?

[Assistant]
To know why it heals you have to know that a bruise is just a bunch of broken blood vessels in the area of impact that are leaking blood.

Our body can fix this because it's a giant pump and filtration system. As the broken bits heal our body is continuously pumping blood/fluids through and around the healing area which break the bruise (leaked blood) down and put it into the filtration system to be cleaned.


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

[User] [General Fiction] Who is the worst fictional President of the United States?

[Assistant] In Judge Dredd, the last President of the USA started the Doomsday War with the Soviet state.  He was so terrible that the citizens threw him and the Constitution out and replaced them with the Judges.


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

[User]
ELI5 How do folks make sun dried tomatoes without bacteria or bugs ruining the tomatoes?

Thats pretty much the post, I have always eaten them without knowing how they are safe to eat.

[Assistant] They're treated with salt before being laid out to dry.  Then since they're losing vast amounts of their water during the process, they're less hospitable environments for bacteria to grow.  Between losing so much water and containing a bunch of salt, bacteria really don't have a chance.


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

[User]
[DC/Marvel] Do superheroes have poor communication skills? It seems as though every time two superheroes meet (especially if it's their first time), they fight each other immediately.

Superhero A meets superhero B.

A demands what B is doing here, to which B tries to explain.

A ignores the explanation and starts a fight with B. B doesn't try again and instead fights A.

A/B wins the fight, or something proves that B is trustworthy.

Why are a lot of superheroes so easily provoked? Why can't they continue to try and explain, rather than fighting back? They have every right to defend themselves, but to fight back?

[Assistant]
When you're a hammer, every problem looks like a nail.
Most situations these folks face end up being solved by a judicious application of their powers in order to get what they believe to be the right thing to happen.
Most times, someone trying to explain is stalling for time, and trying to explain yourself just wastes time.


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

[User]
ELI5: Why does drinking cold water not burn a ton of calories?

Science class taught me that a calorie is the energy required to raise the temperature of one gram of water by one degree Celsius. Since energy cant be created or destroyed, why cant we get skinny relatively quickly by drinking a bunch of cold water?

[Assistant]
1 pound of fat is roughly 3500 nutritional calories. Each calorie we talk about in nutrition is a kilocalorie, or 1000 actual calories according to the scientific definition you provided.

Lets assume you have an 8 oz glass of water at 5 degrees Celsius, which is roughly the temperature of a refrigerator. Your internal body temperature is 37 degrees Celsius, so this is a difference of 32 degrees. An 8 oz glass of water weighs 240 grams.

Raising one glass of water to body temperature therefore burns about 7680 calories (240 grams * 32 degrees). If you need to burn 3.5 million calories (3,500 kilocalories * 1000 calories/kilocalorie) to burn one pound of fat, you would need to drink 455 cups of water to lose just one pound.

You would probably die of electrolyte imbalance before you made any tangible difference in your weight by drinking water.


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

[User]
[Star Trek - Alternate Reality] Why hasn't Scott's transwarp equation made Starfleet obsolete- or entirely different?

WARNING: *Into Darkness* spoilers follow. Read at own risk.

Khan was able to teleport straight from Earth to Qo'noS and Scotty was able to beam aboard during warp, so the Prime Universe limitations seem to have been stretched significantly, if not outright broken. As witnessed during Spock's clever destruction of the USS *Vengeance*, it's also possible/easy to engage in combat by simply beaming torpedoes onboard.

What do ships have to offer that they've essentially retained their role despite the advances in teleportation/beaming technology?

[Assistant]
> it's also possible/easy to engage in combat by simply beaming torpedoes onboard.

No, it's not.  Khan had willingly lowered his shields and allowed the torpedoes to be beamed onboard; further, that had nothing to do with transwarp, as both ships were in normal space at the time.  Any Starship captain worth his salt is going to keep his shields up during combat, and if your shields have failed to the point where your opponent can beam torpedoes aboard, then it's not going to really matter much anyway.

The transwarp equation allowed for a genetically engineered superhuman to make a one-time use device that was easily traced to its destination.  He was unable to bring any cargo with him and the device was quite large, making him vulnerable when he used it (albeit he  solved this by being in a gunship).

Here are the advantages of the transwarp device Khan used:

1. Instant transportation
2. Long-distance transportation

Here are the disadvantages:

1. Vulnerability during use
2. Traceable
3. Does not allow you to beam to places you do not have the coordinates for
4. One-time use
5. Cannot go into space
6. Personal use only

Here are the advantages to a starship:

1. Able to actually go into space
2. Able to beam to places without prior knowledge of coordinates (as you are in a ship and capable of finding said coordinates in real-time)
3. Not vulnerable; surrounded by a massive starship
4. Can beam and move cargo or multiple people at once
5. Reusable

The disadvantages, of course, being that it take a few days to travel.

Starships offer a better advantage in almost every way other than instantaneous transportation.  It is a proven science that is superior in scale, protection, and engineering than the use of personal devices for long-distance transport.


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

[User] [WorldWar] why is Sam the only character able to logically deduce things about the Lizards, the other characters keep being amazed by obvious things like that every lizard doesn't know how all their technology works, or that they can eat earth food?

[Assistant]
Sam is a science-fiction fan, so he's probably spent hours imagining an alien contact every day for his whole life (like most scifi fans). So when they do come he is (a) ready to learn and (b) has researched and kept up with the latest theories on aliens. His guesses just turn out to be correct, and he snowballs from there to become the biggest expert on the Race.

Or are you asking why everything goes right for Sam?

He is basically a Turtledove stand-in. He gets to do herioc adventures, despite being seemingly unqualified, and lucky that his guesses work out. He even bangs the hot girl after her physicist lover is forced by a completely unreasonable government to move across states for a completely idiotic reason, culminating in Jens' attempt to betray the U.S. to the Race, thus getting him out of the way and avoiding any unfortunate questions about Sam's character.


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

[User] Why do things appear darker and more colorful (e.g. stones) when they are wet?

[Assistant] The surface of many objects is rough on a microscopic scale, which is in large part responsible for the bright diffuse reflectance. When the microscopic roughness forming the surface is coated with water, the water fills in the tiny gaps which are otherwise filled with air. Because the difference in refractive index between the water and the stone is much less than the difference between the air and the stone, the wet rough interface will scatter less. There is also a new interface created (air/water). However, because the new boundary between the air and the water (covering the stone) is fairly smooth, it will not scatter light very much.


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

[User]
[South Park] What, exactly, is the mechanism that maintains Kenny's immortality?

If you don't know, what's your best guess?

[Assistant] Iirc, it is due to his parents going to Chtulu cult meetings while his mom was pregnant with him. When he and the rest of Coon and Friends were banished to the Lost City of Ry'leh, Kenny/Mysterion said that the city felt...familiar.


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

[User]
Why does vision black out when the eyes are fixed on a single spot?

If you've never done this, give it a try. It takes a lot of willpower. You have to hold your eyes perfectly still and not let them go out of focus. It should happen immediately. Your vision should grow dim with bright lights like you get when you close your eyes.

[Assistant]
Your eyes are more or less designed to appreciate movement. When something sits on the **exact** same spot, which is difficult to accomplish by the way, a few things happen due to overstimulation. I'll explain this further pretending that cones are much larger than they are:

Let's pretend that you have one cone (ConeA) focusing on a volleyball. As you focus, with no eye movement, ConeA inhibits (see lateral inhibition) the other cones around it. Overstimulation of this cone results in your brain ignoring the signal. Now the ball is black. Once you move, it becomes understimulated while the previously inhibited cones are no longer inhibited (the effect completely breaks once you move your eyes). This results in a negative afterimage once you move away and stare at a white wall.

Motion stops the above effects from happening, because motion is what our eyes really care about. Motion is danger, food, and a bunch of other things that are important to our survival. Stable objects are boring.

Still, to avoid this effect when looking at a stable object our eyes developed microsaccades, tremors, and drift. These help us focus on a stable object without it disappearing, and they're pretty much uncontrollable. It's possible to get past this in certain conditions, but unlikely in everyday situations.

Edit: Let me know if you need/want more depth or simplicity, or if that's not what you meant! Always happy to re-answer if you didn't get what you wanted.


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

[User] ELI5: What does the weather forecaster mean by dewpoint? How does it relate to humidity?

[Assistant]
There is pretty much always water in the air. Humidity tells us how much water is in the air, relative to how much *could be* in the air.

The amount of water that *could be* in the air depends upon the temperature of the air.

So, let's say it's 75 degrees out and the humidity is 80%. If the temperature dropped, the humidity percentage would go up, even if the actual amount of water in the air did not, since the maximum amount of water that *could be* in the air has decreased.

So, what happens when the air cools down so much that it hits 100% humidity? If it cooled down any more, there would be more water than the air can hold. At this point, the water in the air drops out as a liquid, forming fog or dew or rain, so that the humidity never rises above 100%. The temperature where this happens is the dew point.

For almost any amount of water in the air, there is a temperature where it will reach 100% humidity and liquify. So, for any humidity/temperature pair, there is a dew point where the water in the air will start to drop out.


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

[User]
[mcu] is what the avengers do at the beginning of age of ultron murder?

im having this debate with someone and to me it is. they didnt have to kill most of them, especially they didnt have to do it while joking, and showing no remorse afterwards.

sure most of them dont have problems with killing but my point is that they kill them even when they didnt have to. they knew the base capabilities and could have stealth their way in or used the iron legion to dispose of the most of the goons in non lethal ways or used night night guns but didnt. it was literally a massacre.

[Assistant]
Hydra is classified as a terorrist organization. It has aided or personally caused millions of deaths and is a major enemy of government organizations, and the people they killed were wielding illegal alien weaponry. Avengers is a vigilante organization granted general policing powers by governments and SHIELD. As such, legally, their deaths count as killing, not murder.

In terms of why they did this, HYDRA is a terrorist organization that has aided in or has killed millions of people. They have no reason to pussy foot around as that may let their higher ups escape with weapons that could kill millions more people.

And we saw that was what the higher ups were trying to do.


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

[User] Which stimuli reactes the fastest? Visual, auditory or tactile?

[Assistant] Our hearing is the fastest.  There is an excellent radiolab podcast where they tackle this, here is a clip from the episode, "Hearing is our fastest sense. (Who knew?!) Horowitz says that it takes our brain at least one-quarter of a second to process visual recognition. But sound? You can recognize a sound in 0.05 seconds. And our brain is so adept at hearing the differences between sounds, we can sense changes of sound that occur in "less than a millionth of a second," according to Horowitz's book. Why this need for auditory speed? It's our evolutionarily-shaped emergency response system. It let our ancestors hear a twig snap in the woods at night, when all was supposed to be quiet and they couldn't see. Yet, for most of us, we're wired to tune out non-essential sound, so the world doesn't feel like a sensory overload".


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

[User] [Mario Bros.] What exactly are coins, and where do they go when Mario touches them?

[Assistant] The Mushroom Kingdom has very good tailors. You need your pants to have pockets that are bigger on the inside than the outside? No problem, *really* common request from adventurers and heroic types, they're only 45 coins. They're *giant gold coins*, after all, and it's not like making magical overalls defies physics any more than anything else in this place.


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

[User]
[Batman] Would Riddler stop his criminal activity if Batman simply said "You're smarter than me". Does he have any goals or aspirations aside from proving he's smarter than Batman?

In the Arkham games, it was honestly kind of hilarious how much time, money, and effort Nygma dedicated to trying to prove he was smarter than Batman. Most of the other villains had some kind of other goals in life but it seemed like Riddler literally woke up every day wondering what puzzle he could make that Batman wouldn't be able to solve.

Could Batman shut him up forever if he just said "Riddler, you're smarter than I am and always have been" just to give him the validation he desperately needs?

[Assistant]
Sadly, no. The combination of his Narcissistic Personality Disorder and his Obsessive-Compulsive Personality Disorder means that he can't just accept someone just saying that he's smarter - he *has* to prove it.

This came up in the comics twice with the first time being where he almost got away with committing a crime as he didn't leave any clues... and rushed back to the scene to leave behind a calling card, to his great distress.

The second time was more interesting. His fortune was wiped out by repeated failures so he attempted to commit crimes without his Riddler gimmick, just to get back onto his feet. When Batman showed up to arrest him, he revealed that he had left clues subconsciously telling Batman what he was doing, to his great shock.

This finally got Nigma to admit that yes, he *was* crazy and he needed treatment, being one of the few times he voluntarily went to Arkham Asylum. By the time he was next seen, he went legit and became a PI.


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

[User] [DC] Is Captain Marvel (in Marvel form) legally a minor?

[Assistant] Yes. The law does not take biological maturity in mind when it comes to consent laws only chronological maturity from their DoB to whatever the date was when they performed tasks only legally allowable to adults only.


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

[User] What is the anatomical difference between an achy pain and sharp pain?

[Assistant] Sharp pains and achy type pains are carried to the brain for interpretation by different types of nerves. Sharp pain is carried over Type A-delta nerve fibers which are much thinner than Type C fibers which carry, achy, dull and chronic types of pain.


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

[User]
If coronavirus is spread by people coughing and sneezing how are asymptomatic people spreading it when they don't do either?

I've heard a lot about asymptomatic people spreading it without realising they even have it - but the news says coronavirus is spread by people coughing and sneezing. So how are they spreading it when by definition asymptomatic people don't cough or sneeze?

[Assistant] Spreading by bodily fluids such as saliva can even be passed through family if you share a drink or use the same spoon. Sometimes random coughing or sneezing (due to dust, allergies etc)  without covering your mouth leaves droplets in the air or on surfaces and other people might come into contact with it especially in public places!


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

[User] Why can't we know the velocity and the position of subatomic particles at the same time?

[Assistant] It's not that we can't know them at the same time, it's that we can't know them to *arbitrarily high precision* at the same time. This is the uncertainty principle, which comes about because position and momentum (related to velocity) are non-commuting operators. One very loose way of thinking about this is to use the fact that particles can be described in terms of waves. A particle that passes through a narrow gap (small uncertainty in position) will diffract out widely, meaning that there is a large uncertainty in its momentum.


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

[User]
In the 'Two Slits' experiment when only one electron is fired, how does it produce the pattern that it does?

If there was only one electron that was exhibiting wave-like properties, then shouldn't there be an chance that it could end up anywhere on the 'back wall'? How could one single wave produce a pattern as if there was a cancellation at certain points caused by the interaction of two waves?

[Assistant] The electron is a travelling wave packet, and when the slit width is on the order of the deBroglie wavelength of the electron, it will diffract just like a wave. Since the electron's position wavefunction is a probability distribution, the pattern takes a lot of iterations to become apparent.


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

[User] How is real-time traffic determined with applications such as Google Maps?

[Assistant]
Departments of Transportation have traffic survey systems.  You can see them while driving around.  Usually you see pairs of magnetic pickups in each lane, or a CCTV video camera pointed at the highway.  By timing how long vehicles take to pass from pickup 1 to pickup 2 you can detect the traffic's velocity.  Average out the velocities and frequencies of detection and you can figure out how crowded the traffic is and how traffic is moving.  They also take police/fire reports of accidents and plot them.

Traffic information services pull data created by the DOT and other traffic indicators like how many cell phones a cell tower placed by a highway sees.  This is fed to whatever subscriber system requires it.

Aircraft and Ships actually transmit their positions, and anyone with the right equipment can pick that information up.


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

[User] ELI5: When someone in a biohazard suit exits a environment where dangerous pathogens are present, how is the suit sterilized so it can be removed?

[Assistant]
If that's deemed necessary, a decontamination room where the exterior of the suit is sprayed with a powerful sterilization solution that will kill everything.

The suit may then be subjected to further cleaning after it is removed, depending on the severity and viability of the pathogen.


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

[User] ELI5: How did the western world lay underwater telegraph lines as early as 19th century with their level of technology?

[Assistant]
The Victorians (as we call them this side of the pond) were actually pretty good at organising large scale engineering projects. These were the same people who built railways across the world too.

Without underwater cables it would take weeks or months to have a decent international conversation so given the importance of a telegraph link, and the fact that the technology existed (The first telegraph was about 100 years earlier, and the first transatlantic ship was about 300 years before that), the rest was a question of will.


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

[User] ELI5: Why is it impossible for PS1 games to be HD remastered? Is it not possible to just redo the textures?

[Assistant]
Former game dev here,

It's not impossible, there's just no profit in it for the amount of work involved. The studio would be selling to a tiny niche who would want such a thing, and they can't possibly charge enough to turn a profit at a price the market will tolerate.

On the technical side, game code for a console is incredibly specific to that console. What you suggest would require a near complete rewrite from scratch of these games, and recreation of all art assets - which would require a full scale dev team to port to a modern platform. That, and not only would the code have to be ported, but redesigned to work with modern graphics on this other, modern platform. And then you would of course require full scale play testing to find and fix bugs and ensure the game experience is faithful to the original.

It costs ~$10m to make a low end AAA title, and these ports will cost at least as much, likely ~$20m per title. And if you're going to improve the video quality, it's inadequate to go with an incremental improvement, you might as well go all the way, so the effort required would be demanding, escalating the price. Anything less than what is expected for an exalted title on a modern platform would be a complete market flop. And again, this is for a niche market. Buyers don't buy the same experience again, unless you're Nintendo.


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

[User]
How did the astronauts take off the moon?

It seems like the launching of the rocket from the Earth is not an easy thing. Any little error or deviation can delay the launch.
But how the hell without any equipment, launch station, etc did they manage to leave the moon?

[Assistant]
A rocket engine. But the trick is that the rocket stage that took off the moon only needed enough fuel to bring the Astronauts (and soil samples from the Moon) back to Lunar orbit, where the much more powerful command-service module (CSM) was waiting to bring them back to Earth. Also, the descent stage of the lunar lander acted as a sort of "launch station" and was left behind.

Also, it should be noted that there are many different types of rocket engines. The ones used to take off from Earth are very maintenance-intensive, because we can afford them like that. For example, they're powered by liquid oxygen and liquid hydrogen, which have to be stored so cold that they literally boil in the tanks and have to be replenished continuously during the countdown.

The kind of engine used in the Lunar ascent stage uses hypergolic fuel. This basically means storing two different chemicals that ignite on contact, then making them come into contact on purpose - they don't require an external ignition source, which removes a possible point of failure. Much easier to operate, but much less powerful than a liquid oxygen/hydrogen engine - but that's fine, because gravity is much weaker on the Moon.


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

[User] [Dragonball] Why don't people just wish for Goku to die?

[Assistant]
Shenron's power is technically only equal to that of the current Guardian of Earth. So the Dragon is unable to grant the wish of killing someone if their power level is higher than that of Kami/Little Green.

Similarily, to grant a wish like teleportation on a stronger entity, the entity must willingly accept it.


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

[User] [Adventure Time] Do donut-people in the candy kingdom have a digestive system that goes down both sides of their donut hole, or only one side?

[Assistant] It's likely they don't even have a digestive system. Given that everything they eat is also candy matter, it's possible they just absorb it. Like how Cinnamon Bun ate Princess Bubblegum's "perfect sandwich" but less gross.


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

[User]
[Treasure Planet]How did Captain Flint make world spanning portal creator?

How did he keep it from his crew? Why didn't Silver and the rest of the crew know about it?

[Assistant] He didn't. Treasure Planet itself was in fact an ancient space station created by a precursor race millions of years ago who were capable of opening portals. The map was a control device for it-- a sort of navigational device used by this race that described their coordinates relative to the nearest portal planet.


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

[User]
[Marvel] - What kind education can I expect to get at Xavier's school for the gifted?

I'm a young mutant who just developed the ability to leak a foul smelling purple gas from my eyes.  That's it... nothing else... oh and I can't control it.

Prior to this, I was an honor student in my sophmore year.  My dream job was to be a chemical engineer like my hero, Dolph Lundgren. I was in all of the AP sciences and math classes in school. I was in multiple clubs like the debate club, french club, etc.  I was also bowside on our coxless team.  The way I planned it out; If I stuck to the books like I had been, continued to do the volunteer work at the local shelters.  I would've been a shoe-in for valedictorian.  I might've even gotten into C.I.T or M.I.T...

About my "ability"; while the gas I secrete isn't harmful... it does smell like someone wrapped a cheese wheel up with hair and tossed it into a fire... and anything the gas touches, leaves a foul smelling (again, non-toxic) oily residue behind.

Needless to say, I can't go back to my school.

While I appreciate the Xavier institute coming to me, and inviting me into their school; I don't know anything about them. In fact, prior to my "mutation".. I never even heard of it.  The school I'm in right now is a co-ed prepatory school.  I understand that Xavier himself is a professor there along with Hank McCoy (I've seen his name on some papers I read)... what's the rest of the education system like?  Is there a rowing team? I'm assuming it's accredited, right?  Are SATs done here or do I have to go off campus?

I guess what I really want to know is; will this stupid eye gas (again... non-toxic) prevent me from becoming a leader in the field of chemical engineering?

[Assistant]
First and foremost what you will be learning at Xavier's school is how to control your power. Even if that isn't by means of willpower, he will help you figure out what it would take (think something like Cyclops' visor).

Other than that, it is truly a school and you will be able to continue your education. It's even possible that you might get an "in" to one of your desired Universities.

It is entirely possible that you could become a leader in the chemical engineering field. You've just gotta get some help figuring out your stink-eye thing.


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

[User]
[Batman] How did Bruce Wayne explain Jason Todds death to people who did not know they were Batman and Robin?

When Jason Todd as Robin was killed by Joker in Death In The Family, and before he came back to life, how did Bruce explain his death to others?

Id imagine that as Batman, he explained to allies who did not know he was Bruce Wayne, like Commissioner Gordon, that Robin was killed by the Joker, but what about explaining what happened to Jason as Bruce?

Was he known to be Bruce Waynes ward before his death? If so, what explanation did Bruce come up with for what happened to him in order to cover up the truth that they are Batman and Robin?

[Assistant] He told the truth. Jason Todd went to the Middle East to search for his birth mother, and he and his mother were killed by the Joker, who was living there at the time. The next week Superman and Batman stopped the Joker from murdering the UN, which would have pushed "Bruce Wayne's adoptive ward dies overseas" from the headlines.


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

[User] When a child get's an organ/limb transplant, will the transplanted organ/limb grow with the child? If so, will the organ/limb grow according to the donor child's body genetic makeup or the recipient's?

[Assistant] Some organ transplants (such as heart transplants) need to be reasonably size-matched between the donor and the recipient. That means that a baby can only receive a heart from another baby - there's no room to stick an adult heart in. In these cases, yes, the organ does grow with the child. When they first started doing heart transplants, they weren't sure if this would be the case or if they would have to re-transplant every few years as the child grew, but it turns out that the heart will grow. The donor heart maintains its own DNA (hence the need for organ recipients to take anti-rejection medication for life), and would grow according to the donor's genetic makeup. That being said, the organ would also be receiving input cues from its environment (i.e., the recipient's body) that may influence how it would grow.


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

[User]
[Marvel] What are/were the demographics of SHIELD/Hydra?

What percentage of SHIELD were Hydra? How many of both sides survived the unmasking (in winter soldier)? How much money did they have?

[Assistant]
You might want to look up Agent Coulson and his team to get an idea of where SHIELD stands following the emergence of HYDRA.

But to give you a little overview, both organizations were pretty badly hit in the wake of the Helicarrier launches. A huge amount of SHIELD agents were killed by their former friends when HYDRA emerged, and many of those who weren't found that what remained of SHIELD wasn't worth serving any more. Some, like Maria Hill, went to work in the private sector, while others just took the opportunity to retire. Certain high security compounds became totally sealed off and were able to make it through unharmed, but others, such as "The Fridge," where a number of highly dangerous powered individuals were held, were compromised and the prisoners allowed to escape. Some of those compounds that made it through eventually splintered off into separate groups, like Gonzalez's "SHIELD" which borrowed the name of its parent organization.

Coulson was appointed to Director of what remains of SHIELD, and he's done a fantastic job rebuilding the organization... but it's still small. Very small. They do not have the reach or the resources to perform the kind of feats we saw them doing in prior incidents. It took basically all of SHIELD's resources to reactivate the old helicarrier, as you no doubt recently saw. Running short on man power has been a huge problem, as a lot of former agents just have no interest in returning to SHIELD, and Coulson still doesn't have a lot of trust after his apparent death. As a result, he's been forced into doing some things that the old SHIELD would never have considered, like hiring freelancers and putting together teams of superpowered people who might otherwise have ended up on The Index. Still, SHIELD is surviving, and arguably it's been a real rebirth in the wake of the Winter Soldier incident; they're no longer as big brother-y, and have reaffirmed their goals in protecting humanity.

HYDRA started off in a very strong position, having seized so many valuable assets from SHIELD, but they've suffered a lot of setbacks lately. Almost all of HYDRA's leadership has been taken out, and Baron Strucker was one of the last remaining. But HYDRA is nothing if not persistent, so only a fool would say we've seen the last of them. Cut off one head, and all that...


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

[User]
[DC] What is the speed force and why is it so powerful?

It seems like it's the answer to all of flashs problems. Watching the flashpoint paradox movie, zoom says there's not enough speed force for both him and the flash both to heal using it or move as fast as one another. I've also seen it being used to explain things like flash carrying people without them getting hurt etc.  So what exactly *is* the speedforce?

[Assistant] You've probably already been taught about it as kinetic energy. The Flash's speedster abilities stem from his ability to control any kind of motion, even things like molecular motion (i.e. temperature). He can control motion of any kind at both large and small scales, and he can do a lot of weird things with this power because motion is so integral to the laws of physics in our universe.


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

[User]
[Warcraft] Why didn't the Night Elves join the Horde at the end of the third war?

We see in World of Warcraft that the Night Elves are on the side of the Alliance, rather than the Horde.

Wouldn't it make more sense, that because of the Orcish shamanism, the Tauren drudic culture, and the Darkspear Trolls' connection to the Loa, that the Night Elves would have more in common with the other members of the Horde? These races not only have a connection to the more spiritual and primal side of Azeroth, but they are all considered savage by the races of the Alliance (Grom Hellscream himself comments on the Night Elves' savagery).

I get that the Orcs tend to be incredibly industrious, but so do the Gnomes and Dwarves (though with more elegance than the Orcs), that's not much of an issue with the Night Elves. There's also the fact that the Night Elves and Tauren have shared Kalimdor, and both are the only races (before Cataclysm) to possess any Druids.

Is it because the Orc's defiling Ashenvale was *that* unforgivable? Even if that's the case, the Orcs and Humans banded together after the events at Stonetalon Peak (and both fought the Night Elves as the Legion invaded Kalimdor), and then everyone teamed up at the battle of Mount Hyjal.

[Assistant]
Ok so there's a lot of reasons why the Night Elves didn't join the Horde.

The big one is that the orcs defiled Ashevale and then killed Cenarius -AKA the best friend and mentor to the leadership of the druids , and a highly respected demigod.

Also the trolls and night elves are ancient enemies - so that's a black mark right there.

Also the Forsaken are as opposite to the Night Elves as you can get.

Basically while the Alliance has some of the same problems as the Horde, it has less of them and less baggage attached in recent history as well.


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

[User] ELI5: Why is wifi free in cheap hotels, but paid in expensive ones?

[Assistant] Because people who stay at cheap hotels are more price sensitive and people who stay at expensive hotels are less. If you're shelling 200 bucks a night for a hotel room, you either wouldn't mind paying 12 more bucks for wifi or you're on a business trip and you have a company credit card. Where as if you're a broke college kid booking hotel rooms for your road trip, you either won't pay for wifi or you'll book at a hotel that provides free wifi.


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

[User]
Does your DNA alter throughout your lifetime?

Does everything you come in contact with in your life alter your DNA chemistry in any way? All of your experiences? All of your emotions? Physical damage? Healthy or poor eating? Hygiene?

UPDATE: All of this is amazing you guys. I appreciate all of the effort you all put in to explaining. Its truly amazing; the human body.

[Assistant]
By and large your cells are doing their level best to prevent your day to day experiences from having any impact on your DNA. Just about all chemicals you ingest/inhale from whatever sources (food stuffs, drugs, smoke, oxygen, bacteria) will have some impact on your cell's DNA. Plus some other sources of damage such as ionising radiation like UV light or skin contact of chemicals.

Any time any foreign chemicals can get to your DNA they have the potential of reacting with it and causing changes (damage). Because this is an ever present and continuous risk your cells contain a whole suite of repair systems that detect any damage and put things back as they were. But these systems are not perfect so over your lifetime your cells will pick up random changes just from your day to day exposure to your environment.

 This is also the cause/basis of most cancer, if you're unlucky some cell(s) in your body will end up with the right pattern of damage to send the cell cancerous. In large part the DNA repair systems are there to prevent this happening.

All that being said there are some legitimate changes to you genes that happen in your lifetime. Our immune system has a cassette of genes used to generate antibodies. In our antibody producing cells this cassette of genes is randomised and this allows us to produce cells with near infinite variations of possible antibodies.

Alongside this we also have epigenetic changes. These aren't changes to the DNA sequence,  instead these are tags that can be added to genes to control how they are expressed. This pattern of tags is available to be edited during your lifetime and it does respond to environmental stresses. One good example,  starvation has been shown to have a marked epigenetic impact on people's genes and it has been shown mother's will pass on their epigenetic markers to their kids.


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

[User] [ATLA] Can anyone actually see the ball of air that Aang travels around on?

[Assistant]
Yes. Well, technically no, not the air but the dust and condensation the air picks up and moves around. Like a tornado.

Sitting on a ball of air means that air has really high pressure. That pressure is going to grab whatever it touches. That ball is going to condense any moisture in the air.

Yeah, itll be visible.


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

[User]
Why are the dynamic linker and the link editor both called `ld`?

On my system, the dynamic linker (used when loading the program) is named `ld-2.29.so`, and the linkage editor (the last step of compilation) is named `ld`. Is there a reason these two separate things are both named ld? It caused be a lot of confusion initially.

[Assistant]
Historical incidence. `ld` originally was short for `load` but it's purpose evolved over time but it's name never changed.

They are both linkers. The `ld` executable is the static linker and `ld.so` is the dynamic linker. When you consider that they do the same exact job, just at different times, the suffix is actually quite accurate.


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

[User]
ELI5 Brain fatigue

Why can't I study for hours on end? Why does my brain feel weary and unable to learn after hours of work, and why does taking a break help?

[Assistant] While it is working, your brain (and the rest of you, but especially the brain) produces adenosine, a chemical which slows down your thinking, among other things. This forms a homeostatic feedback loop that keeps physical and mental activity at a reasonable average level so that you don't overwork and injure yourself. Your body breaks down adenosine *almost* as fast as it is produced, which causes it to build up throughout and make you tired until you go to sleep, at which point you break it down faster than you produce it. This is why stressful physical or mental work causes you too feel dazed and sleepy. As a side note, caffeine stops adenosine from working but **not** it from being produced, which is why caffeine will not make you more awake when you are already tired and why you feel very tried all of a sudden when the caffeine wears off.


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

[User]
Do black holes gain Mass when absorbing photons? Like light, microwaves, ect.

If so, how much mass is gained from the night sky over time? How does that compare to the mass lost to hawking radiation?

[Assistant] They gain energy, so they gain mass. For all black holes we know this exceeds the energy loss from Hawking radiation at the moment - even the cosmic microwave background is exceeding it, light from stars is added to that, and of course you typically have at least some infalling matter. Hawking radiation will only "win" in the distant future. Small primordial black holes (if they exist) could emit more radiation than they absorb.


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

[User]
[Samurai Jack] What was that dark, smokey stuff Ashi's trainers dump her into early on inseason 5? It looks like it coats her body somehow, but surely it wasn't just hot coals.

Any ideas?  The idea of dumping a child into hot coals is ... yeah.  That's some ancient Assyrian shit.  And I'm pretty sure 3rd degree burns all over your body don't result in a slick black body suit, so what in the hell WAS that stuff?

[Assistant]
Nope, it's hot coals. But remember, the children were all conceived of in a grand magical rite; either Ashi herself was supernaturally resistant, the coals were somehow magical, or a combination of the two. (Given the fate of her sisters, I'd probably attribute more to the coals than the kids; they didn't seem particularly able to withstand punishment any more than anybody else, unless it was maybe just fire resistance they had)

But yeah, that's charred skin she was sloughing off there, or more accurately scarred skin grown over ash. That she had enough real skin underneath to not be a giant walking scab is also signs of magical involvement.


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

[User]
ELI5: Why no nuclear *research* subs?

There was the NR-1 but it was decommissioned in 2005. It was extremely useful for longterm expeditions as a sort of mobile habitat. We now have a fleet of something like 71 nuclear subs, none of which have ever been used in battle. Can we really not spare *one* for scientific use?

[Assistant]
They have been used on occasion.  They are **warcraft**, expensive ones, designed precisely for the mission of guarding a nation.

We can further lament that far too much is spent on weapons, that not enough is allocated to fundamental research for the betterment of mankind.


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

[User]
How would a planet having two suns affect the temperature? Could a planet with two sons be habitable by humans?

There are planets with two suns, like those in the Kepler-47 system, and how does that affect the overall temperature of a planet. An info graphic I saw listed the "habitable zones" of Kepler-47, what does that mean? (Bonus question : what would that look like sky wise? Would that look similar to Tatooine in Star Wars? Or would be different?)

[Assistant]
It really depends on what kind of solar system we're talking about. A binary star system with a planet could easily be a planet orbiting 1 star, with another star orbiting that first star at an extreme distance. That planet would still be in a binary star system, but the second star would have almost no influence on it.

If however we were talking about a pair of stars that orbit each other closely, it's unlikely that a planet orbiting both of them, at the center of mass, would be very stable. The problem here is that both stars would have to be extremely close in Mass for the gravitation to be stable for a long time.

Of course , as is usual in planetary science, Kepler 47 breaks this notion. But keep in mind that both the planets in that system are high mass considering their distance to the stars. The inner planet is three times the size of earth, and insanely hot. The second planet, the one in the habitable zone, is a gas giant. So no habitation here either.

As for your final question about sunsets, you would see two sunsets that went down together, although the orientation of both Suns would change over time. The second sun is much smaller than the first though, and very close to it, so the tattoine reference is a bad comparison.


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

[User]
ELI5: Why is it that we buy cars from dealerships and not directly from the various automobile producers?

Has it always been like this? Was there ever a time where we didn't have to go through dealerships to buy cars?

[Assistant]
In the early days of the automobile manufacturers did sell directly to the consumer.  Then automobile sales began to boom.  Manufacturers didn't have the capital to create enough dealerships to sell all their cars in every city across the nation so they franchised out to dealerships.  This helped car manufacturers reach consumers fast and get into areas where it wasn't feasible to just sell their cars.  They could franchise their brands to dealers who sold competitor brands.  This allowed continual rapid growth for sales while keeping capital to a minimum.

These franchises feared automotive companies would be able to undercut them if they ever decided to build their own dealerships.  So they successfully lobbied politicians to create laws prohibiting direct sales.  This was done with the belief these laws would protect the small franchises from the large corporations and the belief that dealerships created local jobs.  There was also the belief that dealerships created a more personal experience and lowered prices by creating more competition.  These dealerships also banded together into networks and fought against OEM's if they tried to create their own dealerships.  Not all states outlaw direct sales, and the Big 3 in the past have tried to sell direct in those states.  Yet their own massive independent dealer network would freak out whenever it happened and would threaten to disrupt sales across the country.  So even in states where it's not illegal to sell direct the major manufacturers still sell through dealerships due to threats from other dealers if they don't.

Of course opponents to these regulations see dealerships as nothing more than useless middlemen, especially in an age with so much information available to the consumer.  Why shouldn't cars be sold like most products?  A person can go to an Apple store or Best Buy to get a new Macbook.  Heck, they could buy one from the comfort of their own home by buying one online directly from Apple or an Apple dealer.  Why can't a person do that with a car?  If dealerships truly lowered prices then they have nothing to fear.  These laws appear to be useless regulations that provide little benefit to the consumer while adding costs to the process of buying and owning an automobile.  Why not let the consumer decide what they value instead of being told how to buy a car?


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

[User] [Star Wars] Who was stronger in the Force Anakin or Luke?

[Assistant]
If we are going by the old EU Anakin is stronger in the force, but because he was conflicted in his views could never fully utilize either side of the force. In the new continuity it is technically still unknown. Although we know Anakin and Luke were both strong we don't know how strong Luke was because Lucas had not yet created midichlorains.

In short, Anakin but he couldn't use all of his power.


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

[User]
[Warhammer 40k] How is it even possible to fight Tyranid Hive fleets when they contain so much mass they could literally de-orbit target planets without even landing on them?

The Tau I could see managing something (albeit at great cost due to their relatively low numbers) due to being able to adjust their weapons to be exactly as efficient as necessary, but for say... a Space Marine, a lot of their weapons put out way more energy than is necessary at times, and they're bound to run out of ammo.

Do many races beyond the Necron have weapons that can reduce the targets to submatomic particles?  Because even if the targets were atomized surely the Tyranid could still hoover that up while swarming the entire planet after a victory.

Are the fleets not quite as dense as depictions on galactic maps tend to indicate?

[Assistant]
This would be why they often dont. Afaik, only a few successful defenses of major tyranid attacks are covered in the lore. Baal was definitely an unconventional victory, but the hive fleet was legit defeated in Ultramar so thats at least one.

The short guide to repelling tyranid invasion is trying to last-out the ground war until another friendly fleet can reestablish orbital supremacy. If you cant eventually win the war in space, you just cant win the war on the ground against tyranids.


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

[User]
Assistant professors competing against post docs for tenure track position

I just received an email from my department (top 5 in my field) inviting graduate students to sit in on faculty search presentations. I noticed that some of the applicants were post docs while others were already established assistant professors at other universities.

I would assume that if an assistant professor has locked in some big grants, it would be near impossible for a post doc to receive an offer. This is a bit disheartening as a graduate student because it seems like the chances of getting a tenure-track position at a good university are even more tenuous if one must compete against applicants who are already assistant professors.

For those of you familiar with the faculty search process, how are post docs and assistant professors compared?

[Assistant]
Varies enormously by candidate.

Postdocs are all potential, assistant professors have a faculty track record.

If the faculty member's track record is good (grant support, senior authorship on publications) - they're highly competitive as a known, successful quantity. Perhaps the new institution offers a better opportunity or fit (professional or personal) and they're an easy first-choice hire.

However, if their track record is bad - they're viewed with prejudice as having "failed" once, what's to change? If they're going from a high tier institution to a lower tier, there will also be questions about whether they couldn't hack it, or lacked ambition (the candidate can address these questions very successfully, but will need to say something about their decision).

Good faculty members definitely have the leg up when in comes to relating to other professors as peers, and they (generally) have a far better sense of how to present their work, questions, and other considerations from a perspective that will gibe with the expectations of a professor. For example, they can inquire more competently about institutional support, submitting grants through the university office, and have a better sense of how the overhead and budgeting work. They also will have higher expectations in terms of differentiating themselves from the work of their own former supervisors, which postdocs don't need to do as aggressively (vision should still be unique, but all preliminary data can be from the mentor lab leveraging his/her resources and collaborations).


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

[User] ELI5: Where do all the massive amounts of bones and skulls come from in major catacombs such as the ones in France and why did people use these catacombs instead of conventional graves?

[Assistant] They didnt get put in the catacombs right at death.  They'd get buried first, but graveyard space was limited and when people were buried, it wasn't for forever.  After a few years, those people were dug up and their bones were put into the catacombs for long term storage.  So when you see the massive numbers of skulls and bones, that came after this was done for decades or even centuries.


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

[User] [General Sci-fi] In space warfare, what is the difference between rocket, missiles, and torpedoes?

[Assistant]
Rockets are typically unguided. Missiles are larger and have some form of guidance to them. Torpedoes are essentially giant missiles with larger payload and more range.

For instance, you'd use rickets for large area effect. Missiles for fighters/bombers and maybe small capital ships. Torpedoes would be reserved for capital ships where you needed to punch through large amounts of armor/shielding over greater distances.


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

[User] Can you melt wood?

[Assistant]
Wood will pyrolyse or thermally decompose into simpler organic (carbon based) molecules. These are given off predominantly as gases. As this happens you gradually get a more carbon rich solid; charcoal. So no it doesn't melt. Even further and you'd end up with something you could probably call carbon which would then melt at 3550 degrees C.

The point is, wood is a complicated material both structurally and compositionally. So trying to apply to it an understanding of the effects temperature has on materials that is normally used for simpler materials (such as the elements) doesn't work. Wood is not made up of lots of indistinguishable hard spheres and so it won't have a simple phase diagram that nicely transitions to solid, liquid or gas.


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

[User] ELI5: why does gum get so tough after drinking water while chewing it?

[Assistant] It's not so much the water as the temperature. Basically, the long strands that make up chewing gum and give it its elastic consistency seize up when it gets cold; the water is cold enough to make the gum less elastic, which makes it much harder to chew. (A side note of this is that gum becomes much easier to get out of hair when it's cold. It's for that reason that it's often recommended to use cold water to get gum out in case of a chewing mishap, because warm or hot water will just make the gum runnier and let it spread further.)


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

[User]
why should we trust our Intuitions

Is there any reason at all to believe in our intuitions of the external world,  Objective morality, and free will?

[Assistant]
That depends in part on what you mean by 'intuitions'. Herman Cappelen has a relatively recent book about the issue, *Philosophy Without Intuitions,* where he considers some possibilities and argues that 'intuition' doesn't pick out anything distinctive. If you have a specific view of intuition in mind, you might elaborate on it a bit.

But if you're asking the more basic question about what our evidence is regarding the existence of the external world, in metaethics, or regarding free will, then obviously the literature on all of those topics is immense.

Some quick recommendations are: John Greco, 'How to Reid Moore' for an interpretation and defense of Moore's proof of an external world, Russ Shafer-Landau, *Moral Realism: A Defence*, for exactly what it says on the tin, and several of Alfred Mele's books (*Free* or *Free Will and Luck)* for arguments against skepticism about free will.


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

[User]
[Dragon Ball Z] How strong is King Cold in relation to other characters?

We only see him briefly before he is dispatched by Trunks. What character is he comparable to in terms of strength?

[Assistant]
Stronger than Yamcha, weaker than Goku.

Edit: Actually, probably around ssj Goku's level if not a little stronger. It's implied that Frieza got stronger with the upgrades and that King Cold is a couple notches above his son's final form, in order to keep him in check. They appeared pretty soon after the Z Fighters arrived to Earth, so their training wouldn't have progressed too far.


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

[User]
ELI5: The difference between European-style football and South American-style football, and what I should look for in the final game of the World Cup.

I heard on NPR recently that Brazil (and other South American teams) play a different style of football (soccer) than European teams. I'm not savvy enough to notice the difference all by myself.

So what are the differences, and when I watch Argentina vs. Germany, what should I look for to see the differences for myself?

[Assistant] I would say that's incorrect from NPR. It's more that most nations have a traditional playing style e.g. Italy: deep defensive line and counter attacking, brazil: attacking with lots of flair, England are stereotyped as playing long balls up to a target man. Recently Spain have been defined by their possession based short passing tiki-taka game. You could vastly generalise by saying European teams are more defensive than South American teams but as football has globalised all the styles have kind of merged and styles have become less nation specific. Changes in style nowadays are more depend on the managers mentality rather than the origin of the team.


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

[User]
CMV: There is no point in living if Death is Eternal Oblivion

 I was raised in an environment where I was always around my very conservative, very christian Grandparents who would constantly push their views on me, and as a child I accepted them and practiced Christianity on the daily.

As I have grown up (I am now in High School), I have increasingly begun to take on more agnostic views, and I have increasingly found a lack of a purpose to living. I am not suicidal, but I have moments where I'm exhausted and simply tired of life.

That being said, I believe there is a lack of point in being alive in the case that Death is eternal oblivion because you would have no recollection of the things you did, the people you talked to, what you experienced, what you accomplished etc. You would simply cease to exist, and to "You" - your life never happened. I wrestle with this thought every day, the thought of pointlessness, the thought of lacking a purpose in life.

I have no idea if this is something that I specifically am wrestling with, or if this is something that everybody wrestles with, and I would love to hear some differing opinions.

[Assistant] Why do you care about what happens after you die though? Is eating a good sandwich suddenly terrible because the sandwich is a finite size and you'll eventually finish it? No, you just enjoy the sandwich even if it will eventually totally be eaten. Life is kinda the same. What happens after you die shouldn't change what you do on a day to day basis because frankly, worrying about after death is a meaningless pursuit.


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

[User] [Naruto] Why did Konoha go back to the 3rd Hokage after 4th died rather than choosing a 5th?

[Assistant] The 4th had not named a successor and in the aftermath of the ninetails attack it was wiser to have the 3rd step back into the role. He was well liked, already familiar with governing, and although he was older he was still strong, strong enough to keep their enemies at bay while a weakened Konoha recovered from the attack.


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

[User] Why does the Curiosity Rover have such a poor computer/limited data storage?

[Assistant]
There's a few reasons for limitations on the computing technology that goes into space.

For starters, various things need to be custom built. A store bought hdd won't work in a vacuum (or when weightless) for a few reasons, and you wouldn't trust something off a best buy shelf to survive the possibly bumpy ride and landing. SSDs, like all solid-state transistor technology that goes into space, has to be radiation-hardened, to prevent components from being destroyed (or states flipped) from particle or cosmic ray strikes. This problem is exacerbated with higher density devices, as it becomes more likely something will get hit when the spacing is closer.

And then there's more pragmatic concerns. Power consumption is a big one. The whole rover runs on not much more than a few hundred watts. People have desktops with bigger power demands then the entire rover. So is simplicity. When you make a $2.5 billion dollar space faring robot your harddrive **can. not. break.** You don't want anything more complicated than it absolutely has to be.

So you're not going to go with the newest piece of tech, you're going to go with something that's tried and tested. And you'll want to run your own tests on the entire system well before you launch it. So it certainly won't be state of the art by home consumer standards as of now, when it finally arrives.


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

[User] Is there a limit for how many frames-per-second we can capture or display with cameras or screens?

[Assistant]
Currently, the limiting factor is the speed of transferring data out of the camera sensor or into the display. A 1080p sensor at 240fps, at 12 bit color depth, is already running at 1920x1080x240x12/8 = 746MB/s - that's a lot of data to handle! To be able to record continuously, it must be compressed and recorded to storage at that speed. Higher framerate cameras usually don't compress in real time, as that would require immense processing power, but instead dump the images uncompressed to RAM, in a short burst until the RAM runs out, and compress afterwards. For example, the Chronos 1.4 can record only 8 seconds (720p 1500fps), before its 16GB of RAM runs out. Light sensitivity is also a challenge, as high frame rates require short shutter speeds, therefore requiring the sensor to be very sensitive, or the subject to be extremely bright.

I guess theoretically we might reach some barriers. For example: even if your sensor can detect and perfectly accurately count each and every photon, for a 12 bit image you need 4096 photons to hit a pixel during a single frame to make it white. With extremely short frames and small pixels, your average light intensity might not be enough even for a perfect sensor.


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

[User] [Minority Report] Why did a shady body part chop shop keep two identical meals in the fridge for the protagonist to eat, one rotten/spoiled and the other fresh? Isn't that just cruel to someone who just had eye surgery and is dying of hunger? Is he just messy or lazy or a slob?

[Assistant] Well for one the Doctor did have a grudge against the protagonist. And for two the ropes tied to him led to the fresh meal but because of him falling he pulled it down and was unable to correctly guess the food that hadn't spoiled.


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

[User] ELI5: How does facebook update itself, yet i've never seen it go down for maintenance?

[Assistant]
Each time you visit facebook, you're hitting one of their hundreds (if not thousands) of servers.

Knowing that, they're probably doing rolling updates across their entire server farm.

For example, if facebook is served by 1000 servers, they might bring down 250 of them for updating, while keeping the remaining 750 up to handle visitors.  Once the original 250 are updated and running again, they'll bring down another 250, so on and so forth.

So at no time are all of their servers down for maintenance.


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

[User] Eli5: If caffeine blocks the chemicals that make you tired, how does coffee sometimes you more tired than before?

[Assistant]
Caffeine blocks the chemicals that make you feel tired from being detecting your brain, however, it doesnt replace these chemicals (adenosine).

These chemicals continue to build up and when the caffeine begins to wear off, the chemicals flood the receptors leading to an increased level of tiredness, much more than you felt prior to consuming the caffeine.


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

[User]
ELI5: How do games with 2-bit color have transparency?

2 bit color gives you four possible colors. Pokemon Red and Blue use white, light grey, dark grey, and black. But the sprites also have transparency. Where is the "transparent" color stored? (edit: since all 4 bits are already taken?)

For instance, in RGB that also includes transparency, the colors are stored with two extra alpha bytes (Red,Green,Blue,Alpha) vs without transparency as just (Red,Green,Blue).

[Assistant]
One of the four "colors" is allocated as transparent.  There's another bit that can say what transparent should be represented as, which in Pokemon's case is represented as white.

So for Pokemon, the color scheme is not white, light grey, dark grey and black.  It's transparent, light grey, dark grey and black.  Transparent is represented as white.

Backgrounds don't need transparency, so they can get the full white, light grey, dark grey, black color scheme.


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

[User] How do bones turn to ashes during cremation?

[Assistant]
They mostly dont. The cremation process leaves behind ash and bits of very dry bone. That is grinded to produce the final product after remains of the knee and hip replacements etc that old people tend to have are removed by hand.

Source: worked at a cemetery and crematorium one summer years ago. Learned also that cardiac pacemakers tend to blow up loudly in the oven.


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

[User]
ELI5: Why don't we cover the Sahara desert in solar panels to power the earth?

It's a lot of unused empty space that sees a lot of sunlight could we not even use some of it to generate power?

[Assistant]
Because the Sahara desert isn't where we need the electricity.  Solar panels require a lot of space per watt, and then transferring that energy to someplace that will pay for it causes lots of energy loss.

There are more profitable deserts in southern California, closer to people who will pay for electricity.


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

[User]
ELI5: why are clothes that are hung to dry crunchy/stiffer than clothes dried in a dryer?

As a lover of soft fabrics, I am curious why even 100% cotton feels stiff or crunchy when hung to dry. Some fabrics are more susceptible to this, others are fine.

[Assistant]
The heat and tumbling action inside dryers helps relax the fibers in clothes so they feel softer. Unless there is a breeze, hanging clothes remain stationary so the fibers dry in a locked, stiffer state. This is why a steam iron needs to be hot to help the steam penetrate and loosen the fibers within wrinkles.

Too much detergent without enough rinsing and hard water can also cause clothes to be crunchier/stiffer.


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

[User]
[The Elder Scrolls] Can I, a non-Khaijit, use Moon Sugar in my cooking safely?

Legality aside, a Khajiit friend of mine got me a bit of Moon Sugar when he last dropped by. Now, I don't wanna end up a skooma addict but like, is this stuff okay to use in, I dunno, baking in place of regular sugar? Hell does it even taste like regular sugar? Khajiit all swear it's really sweet but you know, their taste buds are totally different than ours. Khajiit and Argonian food is always waved off as being too drastically different for us to eat.

[Assistant] Absolutely. Moon Sugar is an integral part of certain recipes, in fact, like Elsweyr Fondue and Lavender Dumplings. Neither of which cause any unpleasant effects from their consumption even in non-Khajiit. Both recipes, in fact, give a bit of a boost to one's magicka. It seems that cooking with Moon Sugar, probably due to a combination of the actual cooking process and the fact that you're not just eating it straight by itself, reduces or even nullifies the unpleasant side effects while still adding pleasant ones.


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

[User]
If you shifted enough electrons through a ring-shaped electrical circuit, would the mass of the moving electrons ever produce rotational thrust?

All there in the title! Dropped out of science after high school chemistry, so that's why I am asking such a silly question.

[Assistant] The mass of electrons would probably never do it, just because there's a factor of 1836 between the proton mass and the electron mass. So, for metals with at least 20+ nucleons, for each metal nuclei, you'd need 400 electrons to have about 1% as much mass. An easier way to induce a torque would be to simply apply a magnetic field through the ring by ramping it up, inducing a current, and thus the electrons will rotate in one direction, the metal will rotate in the other direction, and the net rotation will conserve momentum and generate the appropriate counter magnetic field. So long as the magnetic field in the loop is changing, a current will be induced in the ring.


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

[User]
[John Wick] Why was John so easily ambushed in the beginning?

And why didnt they kill him?

[Assistant]
John had settled into a normal life and thought things were going well, then he was grieving Helen's death. His own safety was the least of his concern.

They didn't kill him because they were dumb thugs who took pride in the fact they could beat and break regular people and get away with it.


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

[User]
Eli5; Asked by my 7 year old; Could you Swim in Marbles?

Inspired by Scroge McDuck, of course. We were discussing how you could not swim in gold coins because they stack together and form into a more solid entity, and are not fluid like water. And then we were talking about ball pits and she asked if she had gold marbles in a swimming pool could she swim in those?

I answered no originally but then realized, I don't know for sure.

[Assistant]
The problem with gold specifically is the density.  Its eight times denser than glass and 19 times denser than water.

You could probably work your way through glass marbles, but gold marbles will collectively weigh many thousands of pounds and youd struggle to move them by hand at all.


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

[User] Why does an ideal fuel:air mixture not burn completely, in practice? Why do the "lean" mixtures used in road vehicles not burn completely, either? Is there leftover oxygen, as well? If so, why is secondary air injection needed? Thanks.

[Assistant] While the ratios of your input may be perfect, vaporization and actual physical mixing of the fuel and oxygen are never perfect. Think of it like a campfire. You have plenty of oxygen around to burn the logs, and plenty of heat. Why don't they combust immediately? It's because the reaction can only happen where the fuel and air are in contact with each other.


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

[User]
[Futurama] Would Fry have had to pay for the prank pizza at the beginning?

Like, he just goes with the prank and kicks back with a six pack and chows down. Would that come out of his pocket even though someone ordered it as a joke?

[Assistant] Technically yes, but it could be written off as any other prank. He technically stole it, but it likely would have been seen as a regular messup or whatever. Then again, it's very like Panucci would have dicked him to make him pay for it anyway.


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

[User]
Is the soil underneath cities nutrient rich, poor or normal?

I was just thinking the other day about the soil underneath cities.

A lot of cities have trees and plants growing in the ground and it occurred to me that cities completely stop the natural cycle of dead things decomposing in the ground replenishing nutrients. On the other hand, they don't have much growing there, so the nutrients are not used up much.

So my question is, is the soil underneath cities nutrient rich, poor or average compared to countryside?

[Assistant] Nutrients are really only applicable to topsoil (the dark layer of soil ranging in depth from inches to a few feet).  The foundation of any building or even a road will be deeper than the topsoil layer so the question is mostly moot.


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

[User]
[MCU] Are there any passive properties to the Infinity Stones?

Does just wearing the gauntlet give Thanos any additional abilities or does he have to actively use the stones?

[Assistant] Ill bet the Gauntlet is designed to prevent non-deliberate use, since the Stones have a habit of backfiring on users.  Otherwise the Power Stone would have him constantly surging with energy and resisting explosion.


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

[User]
[Star Wars] If i'm on the ground and shooting at an x-wing or a TIE fighter with a blaster rifle, am I likely to do enough damage to bring it down?

Besides aiming for the pilot if possible.

[Assistant]
Barring extremely lucky hits or extreme volumes of fire, no. This goes for unshielded craft too. They are made for war, after all, and need to be able to shrug off at least small-arm fire.
You would have better results with a laser cannon, who essensially are a more powerful (and larger) blaster.

Would still need a solid dose of luck to hit a fighter with a single cannon, though. This is the reason they are usually used in pairs or groups of four, and that there usually are many batteries of them working together to flood the air with fire.


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

[User] [Marvel] How might events have played out differently if Bruce Banner had retained full control of his Hulk form from the very beginning?

[Assistant]
he'd be captain america+supersmart.

The Captain was "made" from the same stuff.

For all we know, some secret lab is staffed with People who are secretly Hulk-like beings.
Would be funny to see if a Villain does the "break into top secret lab" routine, throws a few scientists around who then stand up and grind him into paste.


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

[User]
ELI5: Why does pointing a fan outside work better for cooling a room down?

As opposed to pointing it inside, which always seems to feel better.

[Assistant] A room which has heated up throughout the day can be effectively cooled by moving the hot air to the outside and replacing it with slightly cooler air. The only reason why it feels cool to have a fan blowing on you is due to the latent heat effect of the evaporation of moisture on your body. As the water evaporates, it takes energy from your body in the form of heat which is why wind chill can often make a day seem colder than it actually is.


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

[User]
[Marvel] Spiders-Man is thousands of spiders in a hivemimd that all think they're Peter Parker. If Thanos snapped his fingers, would half of the spiders get snapped or would all of them have to go because they're the components of a "single person"?

In the same way that people's clothes and prosthetics would get snapped even though they weren't technically part of them, they were a part of their identity. Would Spiders-Man be considered a person that would have the spiders count as their "identity"?

[Assistant] We're essentially just a mass of various living cells working together to form a human. Just like how people didn't partially perish or just our brains didn't turn to smoke, the hive-mind Spiderman would likewise disappear.


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

[User]
ELI5: Why does so much stuff cause cancer?

Everyday I seem to read 'scientists have discovered X causes/linked to cancer'. Why are so many things we eat, use and interact with on a daily basis linked to cancer?

[Assistant]
Cells are always dividing and reproducing.  Many (not all) cancers are caused by a cell having a random mutation that causes them to reproduce much faster out of control.  These cells continue to build up too rapidly until they form a lump, or tumor.

There is always a low risk of cancer at any time for any cell.  These mutations can just happen.

When something harms your body by damaging cells, your body reacts appropriately by increasing cell regeneration to heal.  Increased cell regeneration = raising the odds that a cancerous mutation can develop.

Sustained activity of destroying cells, like regular smoking for many years, keeps your body in a perpetual state of rapid cell growth.  Your body can continue to produce cells too rapidly until one mutates poorly and they develop a tumor.

In the end, strictly speaking statistically, virtually anything that damages cells in your body can be linked to increased rates in cancer.

I'll also note here that not all cancers work like this, but many do.


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

[User]
[Batman] How long did Bruce train with the League of Shadows?

Additionaly, if it was long, why didn't he have any of clue of the League's true intentions? Did Ras intentionally keep him in the dark? Wer all new recruits kept in the dark?

Did Bruce think like "Ohh these guys are training me to be an assasin. I guess they use their abilities to help people."

[Assistant]
IMDB cites the movie novelization of Batman Begins and it mentions his training time with the league of Shadows is just under a year.

> Later, [Bruce] reckoned that he had been at the monastery just under a year and that, after the initial period of adjustment, he was happy in the rambling building above the glacier.

Let's just remember that Bruce was already in good shape, had already trained martial arts like Jiu-Jitsu and Kung Fu, and he's supposed to be a genius. Seemed like Ra's was focusing on teaching him stealth, theatricality, and how to properly engage groups of opponents. Bruce already had a good foundation going into the training and it would have come fast for him.

Not sure how to address your other question. Maybe Ra's knew Bruce wouldn't be cool with the idea of being an assassin at first and hoped to convince him by the time of his final test. So he kept him in the dark.


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

[User] [most sci-fi films, including Guardians of the Galaxy] Why do the projectiles shot by guns move so incredibly slowly? Presumably, they either take place in the future or they're more technologically advanced than we are (despite existing "a long time ago...")...but can't beat gunpowder guns.

[Assistant]
Your star lord scene has a whole segment cut out. Korrath doesn't shoot until after Star Lord starts his attack. Star Lord is already diving because he predicts Korrath's obvious incoming shot, he's not diving after Korrath pulls the trigger.

Probably the best specific example is Dune. In Dune people have personal shields that'll stop fast moving projectiles. These shields will react explosively when hit with energy weapons which is usually an undesirable outcome. Which is why in Dune melee weapons like swords and knives have made a big return, as well as fighting styles where people *slow down* their attack at the last moment to move through shields.

Your point about mini guns and jedi is correct. In the movies jedi run away frequently when Droideka (the rolling robots) arrive because they shoot so fast the jedi have trouble deflecting. Along the same lines, none of the jedi successfully defended against clone troopers pouring in volume fire during order 66. Some deflected a few shots but all were overwhelmed.

Star Wars blaster weapons aren't lasers but fire bolts of energy contained in globs of Tibanna gas, blasters indeed have a fairly low projectile velocity. There are still black powder weapons and non blaster guns in the star wars universe.

It's worth pointing out though that many of the defenses that fail against military grade blasters like personal shields and storm trooper armor are pretty much 100% effective against lesser weapons that would be similar to 20th century small arms.


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

[User]
ELI5: How does engine angle in a V setup change the characteristics of the engine?

For example, is a V 90^o better for torque than a V 60^o ?

Edit: I mean the cylinder bank angle, not the rotation of the engine itself.

[Assistant] None of the answers really do justice.   There isnt any difference in the bank angle with regards to power or torque.   Balancing the engine at different bank angles is different but doesnt mean one angle is necessarily better/worse than another.  The biggest reason is packaging.  Fitting the engine in a specific sized engine bay will dictate things, the type of valve train changes the head size and the spacing requirements.   This is why you see so many solutions in industry from inline cylinders, 30 degrees in some front engine V6s. 60 degrees in others, 90 degrees in American style V8s and even 180 degree flat boxers.   All different solutions to the packaging problem.


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

[User]
[X-Men] Do mutants still receive other forms of discrimination?

I remember one scene in the 90s X-Men cartoon where Storm travels back in time and receives racism for being black. She sees it as quaint for being discriminated against her skin instead of her powers.

This bugged me. From everything I've seen, one thing doesn't cancel out the other. It just piles on. She'd get hate for being a queer (?) black mutant woman, not just a mutant.

So, how is it in the comics?

[Assistant]
Iceman was revealed to have hidden his homosexuality because he didn't want to be persecuted for it in addition to being a mutant.

Magneto still faces anti-semitism as does Shadowcat.

It's just that anti-mutant prejudice is a lot more accepted by society so that's most of what they face.


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

[User] ELI5: Why do some people smoke all their lives and drink and not get cancer and live a long time while others who don't drink or smoke die early of cancer or other illnesses?

[Assistant] The same reason some people play powerball and win. It's all a ge of odds. Smoking dramatically increases the odds of getting cancer, but the odds were more than 0% before and are less than 100% after smoking.