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

[User]
Is it possible for meteoroids carrying microorganisms from Earth to travel to another planet, such as Mars, and seed life onto them?

And if possible, how likely is a situation like this to occur successfully?

[Assistant]
What you're asking is basically the panspermia theory, that says life can spread between habitable planets when carried by meteors. Research has been done about this by taking extremophiles into space and exposing them to vacuum, radiation, extreme temperatures and direct sunlight. Survival rates were good enough.

The weak link in the theory is atmospheric entry. When the meteor burns up, any lifeforms it carries would be vaporized and destroyed. A possible exception is that lifeforms are carried in very deep a crack in the rock that isn't reached by the hot air outside. ESA has discussed experiments about atmospheric entry in these conditions but none have been performed yet.


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

[User] Could a gas giant have an atmosphere? Where would the border be between "planet" and "atmosphere"?

[Assistant] Gas giants have very thick atmospheres, that is what the gas is. They are often said to lack solid surfaces, so the distinction between sky and ground may be less clearly defined than it is on our planet, though they may have a solid core.


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

[User] I'm going to University in September (UK) to study Economics and am planning on learning some form of coding over the summer as I have a long break and want to do something productive. Does anyone have any advice on what would be the best language to learn that would be applicable to my degree?

[Assistant] I studied in the UK and we used Stata and R/ R studio Highly recommend the latter as it is free therefore easy access for you and your university and any potential employers which makes it very popular!


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

[User]
[Harry Potter] Dumbledore and the elder wand

So, ignoring the elder wand (and the other hallows) in the specific plans to defeat/trick Voldemort in the end...

How important was the elder wand to Dumbledore and his abilities in general?  We are essentially told that Voldemort is the most powerful wizard, except for Dumbledore, though it seems pretty close.  However, during this period, Dumbledore possesses/uses the elder wand as his wand.

How close of a match would the two be if Dumbledore never had the elder wand?  How would the duel inside the department of mysteries gone if Dumbledore had a "regular" wand (lets still assume the "regular" wand is his and "matched" to him properly etc.)?

[Assistant]
Dumbledore was apparently able to defeat Grindlewald while Grindlewald held the Elder Wand, which is supposed to be nigh impossible.

That alone would put Dumbledore up near to top of the list of wizards who ever lived, and even higher up the list of currently-living Wizards.

There's a reason Dumbledore is the only one Voldemort ever feared.


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

[User] Does it take more energy in transmitting electricity uphill than it does downhill? Is the loss during transmission more in one of the two directions?

[Assistant] Very, very small difference, so small because gravity is so much weaker than electricity. An electron going through a potential of one volt is a convenient measure of energy called an electron-volt (equivalent to ~10^-19 Joules). An electron moving up one hundred meters requires an energy of about 5 billionths of an electron volt. So in terms of circuits, the voltage required changes by billionths.


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

[User] There is no possible world in which the world does not exist. Does that mean that the world necessarily exists?

[Assistant]
If we follow Lewis' conception of necessity and possiblity, then something similar to what you are talking about does follow.

According to Lewis, we analyze "Necessarily x" as "In all possible worlds, x". That means we would have to understand "The world necessarily exists" as "In all possible worlds, the world (that world?) exists", which would obviously come out as true.

But let's not get carried away with the result, which does not establish anything very interesting by itself. It does not, for example, establish that *this* world necessarily exists, or (generalized) that any particular world existst necessarily. Likewise, it does not establish that there are no empty worlds. Since in Lewis' framework, worlds are described in terms of sets, they don't "disappear" if they are empty.

But Metaphysics has moved on quite a bit since Lewis. While his account is still a useful way to analyze necessity and possibility, philosophers have become more sceptical that it's all there is to say about modality. Kit Fine, for example, introduced the notion of a non-worldly necessity in his paper "Necessity and Non-Existence" (2004). According to Fine, there are certain facts that are true regardless of the world at which they are evaluated, like your statement of "The world existst.", but there are also statements that do not need a world context to be meaningfully evaluated, like "2+2=4". You can see that, while "The world existst" is true in all world contexts, and thus necessarily true, it is not true regardless of there being a world context, and thus not (what Fine calls) transcendentally true.

There is good reason to think that there is more to modality than possible worlds, and you should not therefor put too much weight on your result. But it is a correct result, given Lewis' account.


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

[User]
[ATLA] Why did the Lion Turtles unconditionally help and protect the humans?

Humans have the troublesome habit of destroying nature and starting fights everywhere they go. Why did the Lion Turtles give them protection and bending powers in the Spirit Wilds, even if the humans were destroying the wilderness?

[Assistant]
Humans have practically unparalleled abilities of creativity and ingenuity, and the lion turtles wanted to cultivate that.

It's also worth noting that nature is pretty good at destroying the natural world.  Humans can destroy an entire forest, but so can a fire, or a volcano, or a tsunami etc.


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

[User]
[Superman] What is the easiest way to Kill a Kryptonian?

Completely hypothetical I have no wish to do harm to any Kryptonian at the moment. However they do pose a rather serious threat so what would be the easiest way to kill one if I was say a billionaire with a lot of friends in high places.

[Assistant] Easiest is relative, but the most reliable way would be a red-solar lamp to weaken them, and then some sort of kryptonite blade to finish them off. That's assuming you don't have access to anything magical.


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

[User]
[Man of Steel] [SPOILERS] What exactly is the Codex?

At first I thought it was just an ancient fossil of an early Kryptonian, but later it's said to contain the genetic material of all Kryptonians. This really got me confused.

The first interpretation I had makes sense for being a cracked skull, but then it lost the purpose.

[Assistant]
Think of it this way: the Kryptonians are master geneticists, capable of genetic engineering on a level as complex as themselves, and possibly even creating entire new species to suit their purposes. It's likely that they discovered, in their development of advanced genetics, that the best way to store genetic information is in bone, organically. They tried digital data, they tried their mass storage technology (the Superman USB drive that was sent with Kal El), but in the end the old ways, the ways tried and tested by natural selection, are still the best.

So let's say you have to store incredibly important genetic information meant to represent the future of your species on a piece of bone... what bone do you use? If it were me, I'd find the skull of an ancestor, for the sake of connecting our future to our past and  for it to be a physical incarnation of the concept of biological/genetic progress. You take the well-preserved skull of a Kryptonian hominid, an ancestor representing where the Kryptonians came from, and you encode the DNA into that skull, to represent the future of the Kryptonian race. t's not just the most functional scientific method, but it's also a powerful metaphor.


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

[User]
ELI5: why on videos of Jupiter can you not see cloud movement like you can on earth?

We can see clouds moving over our planet, but every video I see of Jupiter I dont see movement in the clouds/swirls. Why is that?

[Assistant]
The cloud bands you see on Jupiter are huge. The red storm you can see is larger than the entire Earth. Even with very high speed winds, the distances involved mean that the clouds are barely going to look like they are moving.

When a single pixel represents 100 miles, a cloud moving at 100mph is going to take an hour to show one pixel of movement.


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

[User]
[SCP] Why would ANYONE work at the foundation?

I mean, it's literally the most dangerous thing you can work with, period. People meet fates worse than death so often that simply dying seems merciful. What kind of payment or motivation drives the staff?

[Assistant]
>I mean, it's literally the most dangerous thing you can work with, period.

Prometheus labs collapsed in an orgy of unsafe crosstesting and Apeture-science-level poorly concieved ideas. The Chaos Insurgency flies blind, with their cells ping-ponging off each other on suicide missions ascribed by poorly understood, possibly non-existent higher-ups. The GOC routinely gets into literal wars with supernatural forces. Fucking up at Marshall, Carter and Dark can get you turned into a blood-bag that the higher-ups will use to extend their life. And good things rarely happen to people caught up in the Sarkicists, the Mekhanites or the Fifthists.

 The Foundation is, in all honesty, a reasonably safe environment if you want to be on the cutting edge of research and development, in that it's at least nominally run by humans in service of human interests, with a strong culture of workplace safety and cautious, trial-and-error based analysis. If you've become aware of the anomalous world, and you want to throw in with any faction, I'd argue that the foundation is the least likely to get you killed as a matter of course.


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

[User] [Star Wars] Aside from the turrets on clone gunships and the Death Star, why aren't laser beam weapons more common?

[Assistant] They're sophisticated, maintenance-intensive, power-hungry and prone to overheating, and not much more destructive than an ordinary particle gun. Why bother with them if your shipborne turbolasers can already slag entire cities?


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

[User]
[Star Wars] How did the Death Star blow up planets?

The primary weapon of the Death Star was a massive LASER array. LASER's don't have any kinetic force and only cause changes in temperature. Shouldn't it have just melted the planet instead of causing it to explode?

[Assistant]
The primary weapon of the death star was NOT a purely laser weapon. Whilst referred to as a 'superlaser' this can easily be a slang term for the weapon, or a reference to a single portion of the weapons design. The characteristics of the weapon, such as the speed of the beam (which is much much much much much slower than the speed of light which a laser beam would travel at), and the 'converging' beams (which laser energy cannot do) show this amply. The same goes for the 'turbolasers' on Imperial Star Destroyers and other warships.

As far as the effects, pump enough energy into something and it'll go boom. Doesnt matter if its an energy based weapon on not.


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

[User]
ELI5:Why is the human body not sensitive to radio waves?

Why are humans not able to see,feel or hear radio waves? We are sensitive to the rest of the waves in the EM spectrum. If EM waves are composed of oscillating magnetic and electric fields, why am I not electrocuted by the electric constituent of the Radio waves?

[Assistant]
Radio waves have wavelengths of several feet, so humans are virtually transparent to radio waves, like glass is transparent to visible light. If you have a piece of conductive metal the right length (an antenna), the waves WILL interact and make electricity move in it. Because the signal is so weak and humans are not as conductive as metal,  we dont notice any effect.

But if you stand really close to a powerful transmitting antenna, it can heat up your body (microwaves were discovered this way when a technician noticed the chocolate being melted in his pocket).


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

[User]
[Borderlands] Why are there so many Psychos on Pandora.

As in, I understand that Pandora isn't exactly the best place to live but that doesn't explain why there are so many people who have just gone completely insane.

[Assistant] Some of the companies that came to Pandora to mine its resources used prisoners and mental patients for manual labor. When the resources ran out and the companies left the planet it was more cost effective to leave behind much of the used equipment and all of their "labor force". The now free prisoners and psychopaths over ran the remaining population of people who moved to Pandora to make a fortune for themselves similar to people who flocked to California and established boom towns during the gold rush. When the companies left Pandora the whole world went to shit.


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

[User]
[Star Wars] Is it really more economical to 'farm' moister on Tatooine than ship it in from off world?

Like spaceships seem to be all over the place, wouldn't bringing in some ice from Oort cloud be cheap and easy?

[Assistant]
I mean, people are doing it.  They're not exactly getting rich off it, but they're surviving, so there's at least enough of a market to support that.
Likely the situation is that nobody on Tatooine has all that much money, so bringing in small scale water shipments isn't really worth it, and doing something large scale would flood the market and crash prices such that it wouldn't support itself.


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

[User]
Why doesn't the n-body problem make the rotation curves of disc galaxies unpredictable?

The difference between the observed and expected rotation curves of disc galaxies is explained by the presence of dark matter.

But how do we even have a predicted rotation curve for disc galaxies?

Doesn't the n-body problem mean the radial velocities of the stars in a galaxy are completely chaotic and unpredictable?

[Assistant]
The n-body problem doesn't mean that trajectories are completely ~~chaotic and~~ unpredictable. It just means that there is no known analytical solution for 3 or more bodies. We can still do numerical simulation to an arbitrary degree of precision -- limited only by our computational resources.

The general technique is to calculate the two-body solution on every possible pair of bodies in the simulation, and sum the effects on each body for a given time-step. The number of calculations is proportional to *n^2*, so it becomes time-consuming very quickly. Various methods are used to approximate the result with less complexity.


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

[User] How likely is it that digital data we have right now (of music, movies, pictures, etc) are preserved and recoverable thousands of years into the future?

[Assistant] Such a question is difficult if not impossible to answer. There are too many variables; what country are you talking about for example, as a war or conflict could destroy data storage infrastructure.  Which company because of how likely they would be to preserve data through acquisition or financial ruin. What is the nature of the data; financial data is virtually assured of destruction within the next few decades simply for legal reasons. Ultimately the web of supposition becomes too thick for any level of reasonable conclusions to be drawn.


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

[User] ELI5: If there is such a dire global shortage of helium, why do we still use it to fill up balloons?

[Assistant]
The "helium shortage" is actually a reaction to massive helium stockpiling of the US starting with the Helium Act of 1925 for use in airships and later on as a coolant during the Cold War and the Space Race. The idea was that it may be a critical natural resource similar to oil, but the progression of technology determined that it wasn't really that important and it was decided that the billion cubic meters of the gas we had collected should be sold off.

This dramatically dropped the price of helium for decades, as the US government was selling a seemingly unlimited supply off at bargain prices. The "shortage" is that the US is coming to the end of their fire sale of helium which means the price will begin to rise to the actual cost of production, which means applications designed around the historically low cost of helium now are looking at a big price bump.


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

[User]
Eli5: How are the different types of "athletic" muscle different?

I've seen so many different builds on the "muscular" spectrum, ranging from barrel-shaped power lifters, to wiry, waifish dancers and acrobats, to really chiseled and defined bodybuilders. I know they're all strong and ripped in their own way, but what's the difference as far as approach and training?

[Assistant] You pretty much answer your own question. Power lifters need to have high force output which is accomplished by large muscles, dancers need long, lean, fast twitch muscle for quick movements and lots of flexibility. Your primary training is always by doing the activity you are training for, weight lifters lift larger weights, runners run, climbers climb. Each group targets strength training in a similar philosophy as the sports they are training for.


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

[User]
ELI5, Why is the amount of water required for producing something (food, clothes, etc..) used as a measure of sustainability?

I get that if its produced somewhere where water is scarce its important not to waste it but where I live freshwater is incredibly abundant why does it still matter?

[Assistant]
Industrial production tends to use massive amounts of ressources. If not well managed, even the most abundant of ressources can become depleted given enough time.

Another reason is that industrial processes often cause pollution and if not managed (often mandated by law), polluted water could be dumped back into the environment. The water may not be reusable without (heavy) treatment, therefore not sustainable for the long term.

Another reason could be that a big corporation could set up shop in an area, exploit the ressources without caring about the environment. Once the ressource is depleted or the market has dried up, the corporation leaves. The local inhabitants are now left economically deprived in a degraded environment which could have been better preserved when the moneyed corporation still had an interest in the area.


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

[User]
[MCU] Why was Sandman in "sand form" through out No Way Home?

Through out the entire movie, when not fighting Marko stays in this humanoid sand form, unlike Spider-Man 3 where he can give himself colour and appear like an ordinary person.

Was this some sort of voluntary choice or was this the reason he "needed" to be cured? Cause if it was the former, I don't really understand why he had to br cured, unlike Norman, Otto and Connors, his powers didn't have an effect in his personality, the same you could say about Max to a lesser extent, both can control their powers and could live normal lives.

In fact, taking his powers would make his life worse since he is a wanted criminal and would have more trouble slipping awat and visiting his daughter.

[Assistant]
I figured Flint didnt feel comfortable walking around as his normal self in a strange new universe with magic and crazy technology, a different Spider-Man, and two of his NYCs most dangerous criminals hanging around alongside a giant lizard and some dude with electricity who all died fighting a superhero.

As for his powers getting taken away, it doesnt seem like MCU Peter was making him a cure or planned to, but when all hell broke loose and Flint left he and the other Peters couldnt take the chance he would cooperate after hed already been stuck there so long, an assumption proven correct. Given some of the other things going on it seems like he came back from 2024 like Raimi Peter did, so its possible the latter would seek him out to make sure he is handling the transition alright. Electro also definitely needed his powers taken away, as we see in TASM2 they were severely warping his mind-he may have been more stable in the MCU with its energy, but coming back theres no guarantee.


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

[User]
What CPUs do cars run on?

Sorry if this is the wrong sub for this. But yeah, do cars have brand-name CPUs from Intel or AMD? I just got curious, because I was thinking about it, and when it comes to futureproofing for vehicle-to-vehicle communications, they would want some decent hardware in there. But then again, I'm sure cars in the 80s and 90s had some Atari-grade CPUs to handle whatever KBs of data they had to process.

[Assistant]
Broadbrush info - there are exceptions...

1. There are no x86 (Intel/AMD) processors, they take too much power and get too hot and they're a bit fragile in an auto environment
2. Japanese cars use NEC, Hitachi (Renesas) etc.  American cars use US brands, the Germans use European brand like Infineon.
3. In the past all the semconductor companies designed their own CPUs but these days they almost all license ARM cores.
4. Most of the CPUs in current cars are actually 8 and 16-bit and mostly do simple jobs but the overall trend is toward 32-bit ARM processors.
5. It's a massive and growing market so the manufacturers are desperate to get their chips in cars but the software is growing 10x faster so the tools are more important than the CPU - ARM has the biggest tools and engineer base.


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

[User] ELI5: How do people initially determine the amount of protein, carbohydrates, and fat in a food item?

[Assistant]
Foods are pretty complex, so the tests used also get complicated pretty quickly, but there are a couple basics.  For fat, you can weigh the food first, then wash out the fat with special liquids (solvents).  You can remove the solvents from the fat to get the weight of fat alone.

For protein, people usually look for the element nitrogen.  There are specific measuring methods to get the amount of nitrogen in the sample, and then a mathematical formula is used to convert that to an amount of protein.

Carbs are kind of assumed to be what's left over from the other two kinds of tests.


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

[User]
Why do our eyes involuntarily shut when we hear loud sounds?

For example when hammering nails, i mean wouldn't it be better to look for the source?

[Assistant]
Survival.

Loud sounds are often the result of things hitting each other. Falling rocks, someone getting creative with a hammer, etc.

These types of loud sounds often send chunks flying, so we evolved to close our eyes to shield them from any shrapnel that may get sent flying.


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

[User]
CMV: Service animals should have some kind of required verification, such as official papers or even a special badge or tag for their harness.

Yes, I understand that "WORKING DOG: DO NOT PET" harnesses are there, but anybody can buy those. I've seen many a fake service dog wearing such a harness--I know these were fake service dogs because these dogs barked at everything, jumped at people, and a few have tried to eat the food out of my hand at the bus plaza when I was minding my own business. It sucks that these owners make real SD owners look bad.

I've seen many videos of people's SD's being denied because they don't have any kind of paperwork. Service animals don't have that, and legally you can only ask two questions about the dog. The thing is, not a lot of people know this, and lots of them will deny entry to these handlers and even harass them.

Having actual paperwork (or something less cumbersome) would eliminate the problem of only asking two questions and the ignorance surrounding that rule, and would deter fake SD owners. The papers don't need to have the person's issue or anything. They could just have the answers to those two questions and some kind of government stamp, or even something similar to an ID with the animal's picture.

I feel like there's an obvious issue with this that I'm missing, or else this would be the standard.

[Assistant]
Actual service animals do have paperwork certifying them as service dogs. The law makes it illegal to ask for that paperwork (Americans with Disabilities Act). People take advantage of this and claim all kinds of animals are service animals that really are not.

Also there are other type of animals that are not service animals, but are outfitted similar and have similar names like comfort animals etc. These animals are not service animals and not protected under the ADA, but people also take advantage of this.


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

[User]
Planets can have rings. Can stars have the same sort of rings?

I don't think Sol's asteroid belt would count as a ring because, I assume, it's not nearly as dense as the rings around Saturn. Can a star even have a ring so dense as to be very visible?

Thanks in advance!

[Assistant]
It is definitely possible.

First, a solid celestial body would have to enter the star's sphere of gravitational influence. Then, it would have to pass through the Roche limit. That's the distance where the tidal forces will rip the object apart.

If the object wasn't on a collision trajectory with the star before disentegration, then it will form a ring around the star.


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

[User]
[Avengers] What is the origin/ purpose of the Tesseract? How did it end up on Earth, and why hasn't anyone from Asgard come down to retrieve it?

A friend and I were watching Avengers the other night, and she would not stop asking about the tesseract. Any help would be much appreciated.

[Assistant]
With regards to it's origins, the tesseract is almost certainly an alternate/cinematic universe incarnation of the "Cosmic Cube", a number of which can be found in the mainstream Marvel universe. From Wikipedia:

>The Cosmic Cube is a containment device created by various civilizations throughout the Marvel Universe at various times, including the Skrulls...

>These matriceswhich may or may not actually be shaped like a cubeare suffused with reality-warping energies of unknown composition that comes from the realm of the Beyonders.

Additionally, you'll notice that someone from Asguard did come to retrieve it. His name was Loki and he was the main antagonist for the film.

Odin, of course, cannot be personally responsible for every powerful artifact in the Marvel Universe. He simply takes them into his possession whenever necessity requires that they be protected. In so far as the tesseract is not used for substantial, world altering harm, Odin has no reason to retrieve it.


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

[User]
Would it be possible to put a satellite in joint orbit around the Earth and the moon in a figure 8 pattern?

And has it been done?

[Assistant]
This is called a free-return trajectory, and it has been done. But it's temporary in nature, it can't keep up with the Moon's orbit. The angle of the elliptic would stay the same relative to the Sun, but the moon would keep moving along in its orbit. Once the moon passed by, the elliptic wouldn't be aimed at the moon anymore and it would just be a long ellipse instead of a figure-8. A satellite on this path would probably crash into the moon when it came back to the same part of the orbit a month later.

All of the Apollo moon missions were put on an orbit like that so that if anything went wrong, they could just "not do anything" and the spacecraft would naturally orbit back towards Earth by itself, passing around the moon harmlessly. The astronauts would then make minor corrections so that they would proceed to reentry into Earth's atmosphere.


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

[User]
ELI5: Since F=MA, is no force applied to a wall when leaning on it?

Similarly, if a truck were trying to remove a tree stump with a chain,and the chain is pulled tight but neither the truck nor the stump were moving, is the force 0 since there is no acceleration? Where does this energy go?

[Assistant]
F=ma is not actually the expression.

NET force = ma

The combination of all forces will result in acceleration.

If the combined forces result in zero of net force, no acceleration occurs.  Even though they're are multiple, and often very strong forces present.


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

[User] ELI5: Why do I fall asleep at work/school/want to be awake, but can't fall asleep when I want to sleep?

[Assistant]
When you're doing something you don't want to be doing, your brain tries to escape by putting you to sleep.  This is the other side of being wide awake when you're doing stuff that really interests you - your brain has the energy and focus you didn't think was there.

Also, there's a part of your brain called the ARAS: the Ascending Reticular Activating System.  It's basically a novelty addict, and it tries really hard to keep you awake and going when there's things around to keep it interested.  Cut off all the stimulation and interesting things, and it'll lay off and let you go to sleep.  Turning off the lights and cutting out sounds help to stop feeding it stuff to keep it going.


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

[User] ELI5:What is plastic made of and why do we make so much of it?

[Assistant]
Plastic is made of dead dinosaur food: let me explain!

Plastics are a general category of different materials: Plastic bags are made of polyethylene, bullet proof glass is made with polycarbonate, teflon is good for slippery chemical resistant coatings, polyester is often used in clothes, PET is used in water bottles, PVC is used for pipes. What all these materials have in common is they are generally big long tangled chains of carbon and hydrogen atoms (with other elements mixed in).

Oil is often used as the starting material (feedstock) of plastics because it also is made of long chains of carbon and hydrogen. It can be reacted in different ways to rearrange the chains to form different plastics.

Oil is made of decomposed biomass from a long time ago that has been transformed by time and pressure below the earth's surface.  That biomass is mostly plants and the like from long ago, and could've been eaten by dinosaurs.

Plastic as a category makes a great material in many applications because it's cheap, light, and relatively resilient. As an example, think of disposable medical syringes. It's easy to make syringes by molding molten plastic. It's cheap, so we can just throw away the syringes instead of cleaning and reusing them. It's light: imagine the weight of glass syringes and the cost in shipping them. It's durable: imagine dropping a glass syringe versus a plastic one.


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

[User]
Why does shaking a can of carbonated beverage increase its internal pressure?

If you shake a can of coke before opening it, it will froth up and release as high-pressure foam.  What's happening at the molecular level that causes the compressed carbon dioxide in the liquid to decompress faster after agitation?

[Assistant] shaking the bottle creates tiny bubbles and these act as nuclei for bubble formation when the pressure is released. Without these nuclei bubble formation is mostly by heterogenous nucleation on the bottle walls, and that is slower.


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

[User]
[Lord of the Rings] Would it be possible to encase the One Ring in anything to prevent its power?

Either prevent or reduce the power of the Ring, or the ability for the ringwraiths to find it?

[Assistant]
Tolkien geek here.

This is actually addressed in the books. The suggestions include:

1) Sailing it to the undying lands. This wouldn't work because the 'gods' of middle earth aren't to happy about dealing with mortal affairs. The ring is made of middle earth, and therefore it belongs their. This isn't their fight its middle earths.

2) Drop it into the middle of the ocean. There are 2 reasons this wouldn't work, and both are given. The first being Sauron is immortal, and oceans aren't, or "What lies at the bottom of the ocean may one day be a mountain peak". Also in the Silmarillion. When one of the silmarils is cast into ocean it is thrown back by Ulmo.

3) Building something around it. Really no. The 'lore' (see skill) to build the ring is really only known by a handful of people who all left for the undying lands, and the rings they made were powerful but kinda knock copies of the real ring. So the only person who can build a box to contain it, built the ring... Well technically Morgoth probably could, but he's worse the Sauron.

4) Just keep hiding it in Rivendale. This doesn't work either. While the Nazgul have trouble entering Rivendale with elvish magic and all that. A entire army of orcs wouldn't, because well 25 million orcs verses 300-500 elves is going to be a wash. Because that's how numbers work.

:.:.:

Ultimately the fellowship was formed because Time was on Sauron's side. The longer it took to deal with the ring the easier it would became for Sauron to get it back. Sauron wanted his enemies to be weak, and divided. He wanted them to take a long time to deal with the ring while he quietly crushed Gondor and Rohan.


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

[User]
[MCU] Question about the Bifrst

If Odin's staff can be used to open the Bifrst, as seen in Thor 1, why does Hela need Heimdall's sword?

[Assistant] It's more that Odin can do it, because he's REALLY powerful. It's not the staff doing it, as much as it was Odin focusing his power through the staff. Hela wasn't quite as powerful as Odin, and thus needed an additional tool to make it happen.


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

[User]
[Harry Potter] If I attached a strap to my wand, would the Disarming Charm still work? Would the wand try to fly back but the strap stops it, or would the spell also loosen the strap to do its effect?

I'm not talking about any old Velcro strap, I'm talking about a strong, tight leather strap with a metal buckle or something else durable and not easily shaken.

[Assistant] Expelliarmus isn't the "yank really hard" spell, it's the disarming spell. Its metaphysical nature and capability remains no matter what you do, because it's magic. You might get your wrist mangled if you had a leather strap around it, or your hand might come off, or your wand might have a "spontaneous" magical reaction with Expelliarmus and phase through your hand.


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

[User]
[SCP] do the employees of the foundation have vacation days?

Title says it all. I know that these guys are working with the most dangerous things the cosmos has to offer, but they _have_ to have at least some form of vacation days or days off. Right?

I hope this isn't a question that leads to a [REDACTED]. I'm just curious...

[Assistant]
For the most part, yes. Lots of SCP folks have regular schedules, sick days, PTO, all that jazz. The main exception would be crews on tasks that require deployment away from civilization (like the mobile task forces tasked to ocean anomalies, requiring extended time at sea) or ones with mandatory brain-wiping before departure (like the Montauk Procedure crew), who work more like an oil rig crew, with X number of days on alternating with X number of days off.

And then there's the D-Class Personnel. They work non stop from when they get recruited until they get retired, at which point they take a vacation from being alive.


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

[User] ELI5: If a person is convicted of a crime and gets imprisoned, and then escapes, but then it's proven that they never committed the original crime, can they still get in trouble for escaping?

[Assistant]
Yes and no. Escaping from a prison facility is a felony. And any additional crimes committed during the escape are also still punishable. But if the escape didn't hurt anyone or property and you were found to be innocent while you were on the run it is unlikely that a prosecutor would file charges as long as you were cooperative. It is also likely the facility would insist that you divulge the details of your escape so that they can prevent further attempts.

It would likely also require that you don't file a civil case against the state.


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

[User]
In your gut how do Dandritic cells differenriate between commensal and pathogenic bacteria?

I have been wondering this, I mean can they differentiate. Dandritic cells penetrate their membrane extensions through epithelial cells of gut and react immediately if the sense a pathogenic bacteria, does it react the same way if it senses commensal bacteria??

[Assistant] They can't tell the difference between commensals and pathogens if they are at sites we normally expect bacteria - i.e. in the intestine or on the skin. Your DCs will have a minor response to either. It's not until a pathogen causes disease causing cell damage or bacterial toxins being released, that your immune system including DCs will try to mount a protective response in these sites. So in that way it's about the site and context surrounding the bacteria. If you cut the skin and a commensal bacteria gets in there it will be attacked and killed just like a pathogen.


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

[User]
[Harry Potter] Why didn't Voldemort hire a muggle assassin to kill Harry?

I've only seen the movies (please don't hate me), but it seemed to me when Harry, Ron, and Hermoine were running from Voldemort's thugs they only worried about wizards attacking them. The easiest way to kill Harry (as far as I can tell) while he was in the muggle world would have been to hire a sniper or simply some dude with handgun to run up and pop a cap in Harry. Why is this method not feasible?

[Assistant] Voldemort would be the absolute last person to trust a Muggle with a task that important, or even be seen cooperating with one. Muggles are worse than dirt to him. Now, an Imperiused Muggle? Maybe. But then the question becomes about how much direct control there is under the Imperius curse? Assuming that Voldemort knows next to nothing about firearms, could he direct someone under his control to operate one? Also, Voldemort has no way of knowing what kind of charms Harry may have guarding him. It's possible he wouldn't even attempt it, assuming that Harry would have already protected himself.


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

[User]
Is Mt. Everest the highest point on earth ever to have existed?

AFAIK, Mt Everest is the highest point above sea level, and the Himalaya are still rising. But is there geological evidence for a mountain that was even higher, that perhaps eroded or blew up in an eruption?

[Assistant]
It's impossible to say for sure. The tallest mountain ranges generally form early on in the collision between tectonic plates, before they can slow each other down. This phase of mountain building involves the sedimentary rocks on the edges of the colliding plates. These rocks are soft and vulnerable to rapid erosion, meaning the mountains they push up erode away quickly.

Mt. Everest is a perfect example. The upper 6,000 feet of the mountain are sediments deposited off the northern coast of India 400-500 million years ago. These sediments are mostly limestone and mudstones, which are extremely susceptible to erosion.

Once the sedimentary cover has eroded off, the core of harder igneous and metamorphic rocks remain, but by then the energetic first stages of collision are over, and their rate of uplift is slow enough that erosion can keep pace.

Several mountain ranges may have reached the altitude of the Himalayas in the past. The Appalachians, which involved three large continents with a lot of momentum colliding may have pushed up a spectacular mountain range. Other remnants of this mountain range can be found in the Caledonian Range of Scotland and the Atlas Mountains of Morocco.

The Rocky Mountains of the western US may have also been a much higher mountain range. Between 100-60 million years ago, three separate microcontinents collided with the western coast of North America, then in Idaho, Utah, and Arizona. Each collision pushed the region higher, and what is now Nevada might have been part of a plateau of comparable altitude to Tibet. However, something funky happened with the oceanic plate subducting behind the mountain ranges, and starting about 20 million years ago, the entire area started ripping apart, creating the current landscape of low mountain ranges (6-10,000 feet) separated by valleys not much above sea level.


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

[User]
Why can we ignore the imaginary part of the simple harmonic motion displacement equation?

If you derive the displacement of a mass on a spring from the first principles F = mx''(t) = -kx(t) then you get the equation x(t) = Acos(wt) + iBsin(wt) where A and B are real constants and w is the angular frequency (sqrt(k/m)).

Why can we eliminate the second half of the equation? Is it ever used?

My working for the derivation is as follows, there may be a mistake as google is fruitless:

F = mx''(t) = -kx(t)

x''(t) + kx(t)/m = 0

let x = e^nt

n^2 e^nt + k/m e^nt = 0

n^2 + k/m = 0 as e^nt =/= 0

therefore n = +/- (-k/m)^0.5

x(t) = c1e^iwt + c2e^-iwt  (Substituting w for (k/m)^0.5

Applying Euler's identity:

e^iwt = cos(wt) + isin(wt)

x(t) = c1 + c2)cos(wt) + i(c1 - c2)sin(wt)

x(t) = Acos(wt) + iBsin(wt)

[Assistant]
Once you get to the general solution you have to get the particular solution by applying the initial conditions. Say you know the position and velocity at t=0. This first means that A has to be equal to the initial displacement x(0). Looking at the derivative you have

X'(t=0) = iBw

So unless you have an "imaginary" initial velocity, which is an unphysical thing, B must be a function of 1/i, or in the case of 0 initial velocity, 0/i = 0.

In short, you'd need an imaginary displacement or velocity as an initial or boundary value for B to end up nonzero (or A to be imaginary).


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

[User] ELI5: Why don't all MLB baseball fields have the same dimensions?

[Assistant]
There are many dimensions that are the same, such as distance between bases, distance from the pitcher's mound to home plate, height and slope of the pitcher's mound, the minimum distance to the outfield fence, etc. These standardized dimensions are the most important to the actual play of the game.

The areas where fields are different can be broken into two categories: foul territory and the outfield fence. Both came about in the early days of baseball due to the fact that stadiums had to be located in less-than-perfect locations, and flexibility in fence locations could help equalize fields on different shaped/sized lots (the "Green Monster" outfield wall at Fenway Padk, for example is very tall to make up for the fact that it is rather close-in to home plate, which is due to the fact that the stadium was constrained by a street on that side when it was built). Foul territory was influenced the same way. Odd-shaped lots caused there to be areas where the stands were very close to the a tion, but the strict 90 degree geometry of the baseball diamond sometimes created gaps between where the stands were and where a grandstand that foloowed the property's contours might be.

As baseball became an ever-larger business, these designs became more about local history or creating advantages for the home team (an unusual corner in an outfield fence can cause a ball to careen in a direction a home-team player could anticipate, but that might surprise a visiting outfielder) but there is no outcry for dimensions to become more standardized--in fact, these idiosyncrasies are seen as adding to the charm of the individual parks--so stadiums continue to add their own character through unique outfield and foul-territory dimensions.

These playing differences can be attributed to two simple quirks of baseball. First, the area out of bounds (foul territory, or the area not between the first and third base lines) is still a usable part of a baseball field. And secondly, since offense and defense are played in turns, but by the same set of players llaying both sides, a team can be built according to strengths that take fhe park shape into consideration.

For reason 1: a ball hit into the air and caught in this foul territory counts as an out, so it's construction makes a difference in how a team is positioned and how batters approach their at-bats. On fields with a lage amount of foul territory, more pop-ups will be caught for outs. A pitcher might be more willing to trade a small chance at a long hit in order to try to cause the batter to hit a pop-up into foul territory for an easy out, while the batter will not swing at as many close pitches to avoid fouling a ball into the air in-bounds that may be caught for an out.

On fields with small foul territories, a pitcher won't be able to rely on a as many pop-outs, and may pitch a batter in a way to cause more ground balls to be hit. Batters, on the other hand, will be able to swing more freely because it will be easier to deflect a close pitch into the stands rather than into the air above the in-bounds foul territory of the playing field.

For reason 2, a team with a large outfield can afford to spend less on pitcher's because lesser-quality pitching will be masked somewhat by a more difficult distance to hit a home run. This team would spend more of its budget on fast outfielders who could not only cover the larger area and reduce doubles and triples afforded by the larger dimensions, but who could run faster when batting to stretch singles into doubles or doubles into triples in the larger outfirld, against players no accustomed to covering such an expansive area.


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

[User]
Where does the endless flow of electricity come from in an electrical generator?

Mechanical rotation in a generator (fueled by flowing water, wind power, diesel burning etc) creates electricity.
But the coil of wires and magnets rotating inside the generator is finite in mass, even though the electricity generated is endless. So where do the electrons/electricity come from?

[Assistant]
Short answer: The electrons just wiggle back and forth, being pushed by the generator.

You might have the misconception that electricity works by sending electrons to whatever device uses them and that the device eats them up, like electricity worked the same as burning natural gas for your water heater. But it's quite different. The number of electrons in the generator and all the wires going to your outlet does not change, and the electrons are already there to begin with. The usefulness of electrons comes from their bulk motion. A generator is just creating the force to push those electrons back and forth, and when you make a complete circuit by plugging a device into your outlet then the force of that push is transmitted to your device.


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

[User]
[Bruce Almighty] Could Bruce have remained god?

Ok so Bruce learnt his lesson and handed back the powers. But what would have happened if Bruce was less inclined to do that? God says he gave him *all* of his powers, does this but Bruce on par with God? Could he have kept the powers even against God's will?

[Assistant] No.  God never actually gave Bruce all his powers.  God used his own powers in a way that it appeared to Bruce that HE was doing everything.  Basically, Bruce wanted a monkey to appear, so God made a monkey appear in exactly the way Bruce intended.


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

[User] [DBZ] Why are all the fusions so arrogant?

[Assistant] They seem to take on the flaws of both fighters as well as multiplying their powers. Piccolo points that out to Vegeta in Dragonball Fighter Z when talking about Gotenks. Perhaps they get magnified like the power does. So Trunks and Vegeta's habit of taunting enemies gets magnified.


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

[User]
Why cant we dissolve toxic or radioactive material to make it harmless?

Im curious.. basically everything known to human has a specific arrangement of atoms or molecules. Why are we not able to lets say split up oil or plastic into an endproduct harmless to earth and its creatures?

edit: thanks everyone for your long and detailed answers!!!

[Assistant]
Dissolving it, melting it, etc. doesn't really affect it on the nuclear level. The nucleus of each radioactive atom remains unstable after you do these things.

In fact, now you've potentially made it *more* dangerous by melting it or dissolving it in solution, because it's free to flow around (assuming it started as a solid).


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

[User] [Last Airbender] What cant Waterbenders hurt their adversaries by sucking the water out of their eyeballs, collapsing cells, bursting their bladders or otherwise affect water within a body?

[Assistant]
They can. It just takes a lot of focus and energy to specifically target the water within an animal, and thus it's very rarely done. It's easier to get water from plants, as they have a weaker Chi, and thus have less resistance to waterbending.

Basically, the life energy of a human makes them a bit more difficult for a waterbender to focus on. So usually just freezing them  is easier.


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

[User]
[The Hunger Games] Whats happening in the rest of the world while America / Panem is going through with the Hunger Games?

I mean, theyve basically become an even more violent and brutal North Korea. Havent other countries tried to stop this? If not, why? What does the political climate of the rest of the world look like? How are they faring?

[Assistant]
England is ruled by an isolationist-fascist regime.

Japan in run by an AI-based nanny state that conscripts people with PTSD to work as detectives.

Australia is ruled by warlords and some very creative mechanics.


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

[User] CMV: Brand loyalty is useless, and is currently used as just another bullshit tribal marker.

[Assistant]
> Who cares what brand something is?

Consider you find a mechanic that did a good job for a fair price. The next time you need your car fixed, do you spend a lot of time researching mechanics, or do you draw from past experience and use a *known* good mechanic? Perhaps the mechanic will be drunk the next time he works on your car and make a huge mistake. However, it's more likely you will be treated the same as the last time you went. The mechanic is the brand, and loyalty saves you time, effort, and risk when using mechanics.

Brand loyalty saves us from the worthless and time-consuming task of copious amounts of research before every purchase. If we know a brand to be of a consistent quality in the past, then it's reasonable to assume the same quality in the future.


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

[User] Do any other species besides humans bury their dead?

[Assistant]
Elephants have been seen using sticks and other plant matter to throw onto and partially bury their dead friends and relatives. They also show behavior similar to humans visiting graves of loved ones, such as stopping by old skeletons when they pass by and caressing them with their trunks. They've even been seen "burying" other animals and enacting typical mourning behavior, at least one of which was a sleeping human who had a very rude awakening.

Elephants are crazy smart, man.


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

[User]
ELI5: what causes death from old age?

Why is it humans rarely make it to 100 let alone 100+ what is it that gives out to cause death assuming no illness and why is it so rare for humans to live to that sort of age but some animals have been known to live way over 100.

Edit: ok so I get that basically our bodies stop bring able to repair themselves/keep parts working but why is it that some animals can do it for far longer?

[Assistant]
You don't actually die from old age. Most people die from Pneumonia or some other complication that has to do with aging.

Bust basically your bodies cells are constantly dying. Your entire bone structure is replaced every 10 years. Your skin gets replaced roughly monthly.

As you age you replace dead cells less and less effectively. Until you cannot replace cells effectively in a key place and you die.


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

[User]
[LOTR] How important is a Wizard's staff?

If something broke Gandalf's staff could he make/acquire a new one (without dying that is)? Is he significantly less powerful without it? He can still do some magic right?

If a non-wizard with some magic got a hold of it, like Galadriel or even Aragorn could they use it to become more powerful?

Saruman accuses Gandalf of greedily wanting the staffs of the five wizards, would Gandalf actually be stronger while duel wielding staffs? Could he use five at once?

[Assistant] A Wizard's staff is as important as a king's crown. It has no intrinsic power to speak of, but it has great symbolic significance. We see that the Wizards can get by fine without staffs when necessary - Gandalf breaks his in Moria and is still able to fight the Balrog afterwards - but they are very reluctant to part with them. Gandalf casts Saruman out of the order by breaking his staff, for example. Some like Wormtongue evidently believe that the staffs have inherent power, but Wormtongue also thought that the palantir was a worthless rock and threw it out a window, so his opinions on magic cannot necessarily be trusted.


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

[User]
When a person gets more flexible by training, what is physically happening to their joints?

Besides the obvious like losing excess fat that's "in the way" such as on the stomach, which limits spine flexibility.

[Assistant] IIRC, nothing is happening to the joint. However, the muscles around the joint and connecting tendons are being used more which makes them more pliable and stretchable. If somebody had a lot of fat, losing it would also get rid of the obstructive fat; like taking off a really puffy jacket.


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

[User]
Just got my PhD. Now what?

It all feels less spectacular than it should.

I loved my field when I decided to pursue a PhD. And then I started getting worn out. I dropped out because I was having too much trouble working with other graduate students.

I found a job in the field, and seeing how my profession works in practice killed any last passion I had remaining for the subject.

I ended up losing my job during the pandemic and decided to finish my degree. It was the easiest option, and an option that meant I could stay at home. The passion never came back, but I was able to finish writing and defend my dissertation.

So, now what? I'm working for my advisor and will do so for the next couple of months. I hate every minute of it. Doing anything feels like a hassle. The thing I hate doing most is *writing*, which is not a good omen for a future academic career. I can't imagine doing this for the rest of my life. I feel trapped.

I know I can't be the only person who's gone through this. How did you pivot to something else? How do you find meaning in your work?

[Assistant] Dont try to find meaning in your work, find meaning in your life. Find something that pays well enough with a better work-life balancefor me this year it meant going from a post doc to a government job.


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

[User]
How do metal detectors work?

To clarify, why does not all metal set off a detector? Such as zippers on jeans, or metal buttons? Do these detectors not detect certain kinds of metals, or do they just need at least a certain amount?

[Assistant]
A metal detector makes a varying magnetic field in an area using an electromagnet. Conductors such as metal will temporarily block magnetic fields from entering them due to the skin effect. The driver used to power the electromagnet will be affected due to the presence of large amounts of metal, since it has less space to fill with magnetic field. The power being supplied to the electromagnet will be noticable different, but the amount of difference depends on the conductivity and volume of the material, as well as how close it is to the electromagnet. The distance issue is why an airport security officer will sometimes use a hand wand, since it can be placed much closer to the body.

Conductivity varies a lot between metals. The skin depth is proportional to the square root of conductivity. Stainless steel is 45 times less conductive than copper, so the thickness of stainless steel that is "invisible" to a metal detector is 6.7x more. These thicknesses will still be incredibly thin, at 1MHz the skin depth of stainless steel is 0.5mm.


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

[User]
ELI5: How do scientists determine the possible habitability of exoplanets?

With the search for possible Earth analogs in our universe going on still, how to scientists determine whether or not a planet is habitable even tho often times they can't physically see the planet?

[Assistant]
They can tell how bright the star is fairly easily. From this information they can determine how much energy the star is putting out. Then, they look at how fast the planet is orbiting around its star by measuring how often the planet causes the star's light to dim or wobble. From information about how fast the planet is orbiting they can determine how close it is to its host star.

Now that they have the energy output of the star they can determine if the planet is in the range where water can be liquid. If the planet is too close then all water will evaporate but if it's too far then the water will all freeze.


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

[User]
[Fallout] Who are these Dunwich guys that bought a building near my company?

I'm a wealthy corporate businessman looking for a little dirt on my neighbors just in case we need to expand some. Thing is, I found nothing on them. I mean, NOTHING. Just who are these guys?

[Assistant] Take the advice of an experienced private detective.  Drop it just sell the Land for whatever you can get and move as far away from dunwich as you can get.  These guys make mobsters look like puppies.


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

[User]
The validity of cardinal utility?

Ordinal utility makes sense: someone can value *x* either more or less than *y*.  However, I don't know how cardinal utility makes sense.  Cardinal utility means someone can value *x* at 10 "utiles," *y* at 11 utiles, and *z* at 23.1 utiles.  How does it make sense that goods can be numerically valued and measured in "utiles"?  It would be silly to say "I value a TV at 10 utiles, a house at 11 utiles, and a car at 23.1 utiles," wouldn't it?  So, how is cardinal utility a valid strarting place for scientific inquiry?

[Assistant]
Yes, that is the problem with cardinal utility. That's why economists don't like using it much these days.

For that reason economists today think of utility functions different to the economists who first began using utility functions. Rather than thinking of them as representing an amount of utility, they think of them as representing an ordering of preferences.


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

[User]
ELI5 Why it's called a semi truck.

If that's semi, what's a full truck look like?

[Assistant] The "semi" doesn't refer to the truck. It's called a semi truck because it's built to carry what's known as a semi-*trailer*: a trailer which doesn't have front wheels on it, because it just slides on top of the truck. (There are full trailers that do have front wheels, but they're much rarer.)


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

[User]
[Dune] Would a AI/robot fleeing into unknown space provoke humanity into pursuing it?

OK, so here's a question. I'm semi-familiar with Dune, I've seen the movies, skimmed some of the books and read discussions of them, so my insight is limited.

I get that general-purpose and networked computers are total taboo and not allowed (though Ix did eventually start using simple computers to get around certain tech' problems), any automation is highly limited and analogue (if present at all), however humanity also seems restricted to a specific area of space and doesn't care to expand.

Taking that into account, if an AI/robot was discovered or sighted at the edges of Known Space, it didn't take any aggressive action towards humans, didn't seek to interact with them, and was solely interested in leaving human space and never returning, would humanity attempt to pursue and eradicate?

I guess what I'm asking is, the Butlerian Jihad applies to everything in human space, but would they travel far from their sphere of influence to destroy a thinking machine if no further contact was anticipated, or if that same thinking machine said it actively wanted to avoid them? How deep is their taboo and hatred? Would they be able to ignore such a thinking machine if they'd never see or hear from it again, or would humanity/the Spacers Guild/The Sisterhood/someone else absolutely go out of their way to destroy it?

Any thoughts, examples or opinions appreciated in advance, I'm just trying to get a grasp of some nuance here.

[Assistant] Given the premise that "thinking machines" would evolve and outpace mankind, they would have no other choice than to seek out and destroy any and all existing AI. The initial intent of said AI has no bearing on this. No matter how far, or how many generations pass, the hunt would never end until the task was done.


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

[User]
Cmv: lawn work is unnecessary

This isn't out of a hate of lawn work or anything like that, I just purely do not understand why we decided that half- decapitated grass is the status quo. Why is this normal? Who made this decision? Can I have a yard of cloves and flowers and ferns instead? I think that there are so many other ideas of what could make a "lawn". Why did this start and why can't we change this idea. I would rather every house have a field of flowers or something. I really do not get any of this. Does this keep insects away? Fight me.

[Assistant]
Historically, grass was a sign of wealth.

If you owned a farm, every square inch was valuable. "Wasting space" was a luxury of the rich. Hence, grass.

You are correct that in the modern day, it isn't strictly necessary. You could put any number of plants there. You could make a rock garden. You could put down astroturf.

But much like the wedding cake, the wedding dress, and high heeled shoes, that which the rich used to do, became the norm for everyone, once everyone could afford it.


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

[User] Eli5 why does wet sand stick together?

[Assistant] Damp sand sticks together because water forms little grain-to-grain bridges. Surface tension--the same force that lets some insects walk on the surface of a pond--acts like rubberbands between the grains. Adding water to damp sand fills spaces between the grains. The bridges vanish and the sand begins to flow more easily.


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

[User] [Genral] Who do the number of superheros increase exponential after the first one appears?

[Assistant]
They was never a time without heroes.

Remember Hercules? King Arthur? The Amazons and Atlanteans have been around as long as there have been people, if not longer. There have always powerful men and women ready to take on the evils that threaten mankind. When the times are dark, new lights are lit to push it away.

What has made it look like seemingly massive numbers of them existing is the dawn of media. You can now hear about heroes from all over the world who once would only be famous in their immediate area. WWII also seemed to be a catalyst for superbeings to come out of hiding, no longer able to say they must stay isolated when the world teeters on the edge of collapse. Lastly heroes are now more organized than ever, with groups like the Justice League reaching world wide and recruiting all heroes who want to help.


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

[User]
How can some animals "smell" fear?

I'm sure you've all heard it before, but how do you scientifically explain it?

[Assistant] They don't. Most mammals have good eyesight and are very good at reading body language, and that's what they're responding to. Cringing, backing away, jerky movements, high-pitched noises, and certain eye movements are indicative of fear/distress in a lot of mammals (and more importantly, their prey).


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

[User]
Professors with a research interest on the Phenomenology of suicide

Thought it'll be easier if I asked Reddit.

Hello, I am currently an undergraduate student at the University of Alberta (Canadian citizen) studying a double major in Psychology and Sociology [with a minor in Philosophy and an Applied Social Science Research Certificate]. I just finished my 2/5 year, and am beginning to panic a bit ....

My interests are along the lines of Existential based depression, anxiety and suicide; Phenomenological Existentialism; and social influences on suicide (particularly amongst men and the LGBTQ community).... I'm looking to get an MA and/or PhD in either Sociology or Psychology with a research interest along the lines of "Phenomenology of Suicide"

I was wondering if anyone knows of a professors (those seeking to supervise graduate students) with a research interest in suicide, depression, anxiety, and/or phenomenology. (my focus is on Canadian and United States Universities, but I'm open to ones from Europe as well)

[Assistant] Try looking up Anna Mueller. She is currently at the University of Chicago but is moving to the Sociology department at Indiana University next year. She studies the phenomenology of suicide in adolescents, particularly suicide clusters.


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

[User] [Marvel] Galactus is suddenly erased from existence. What are the consequences?

[Assistant] This actually happened, Galactus got sucked into the Ultimate Universe and no longer exists in the main continuity. The main heroes never noticed it, the Ultimate Universe got rocked, but came out fine.


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

[User] Why do people's noses get runny when they go out in the cold?

[Assistant] The blood vessels in your nose also expand to keep up with their job of warming up the air that you breathe in before it goes further down your respiratory tract. That in turn further activates your mucous producing cells, who among other things help moisten the air you breathe. All of this results in a runny nose!


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

[User]
[General Science] It is 7286CE and you are 1 of 280 billion human brains uploaded to a Noosphere centre orbiting around the planet Mars.

7286CE: you are 1 of 280 billion human brains uploaded to a Noosphere centre in Mars' orbit.

An ET berserker probe swarm hell-bent on destroying all sentient life is enroute to our solar system. From observation, it would appear that the swarm is destroying all advanced forms of life.

Do you recreate physical bodies and leave or what do you do, bearing in mind that our species is still only capable of interstellar manned travel speeds of 0.01%lightspeed - and the swarm is unmanned and capable of much higher speeds?

[Assistant] Why recreate physical bodies that can only attempt escape at an ineffective speed of 0.01 lightyears (that's a distance not a speed btw so lets assume you meant 0.01% of lightspeed) when you already exist as digital information capable of being broadcast as light at lightspeed. That's just asking to get genocided.


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

[User]
ELI5: What is a think tank and what do they do?

In political news stories you often see mentions of "think tanks" that lean either left or right.  I'm curious what exactly a think tank is.  How are they formed?  How are they funded?  What do they do?

[Assistant]
Think tanks are a specific kind of lobbyist organizations that advocates for certain things by employing university level academics to write white papers, policy documents and model legislation. These documents are, of course, the same documents that governments themselves prepare as part of the legislative process, and think tanks contribute their documents to relevant governments free of charge in the hope that the government will adopt the think tank version in whole or in part, rather than writing their own version.

Obviously, as a type of lobbying organization, they may be general purpose and lean towards a broadly leftist or rightist agenda, or they may be single issue or specialist focus in which case they may not really align fully with either party. But they will almost certainly have some viewpoint that they are pushing for.

Like all lobbying organizations, they get started by various people or organizations that want to lobby for a particular viewpoint and who like the think tank model. They are also funded in a whole variety of ways, some by various industries, some by various individuals or foundations, some by political parties, and some are even partly publicly funded.


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

[User] ELI5: What does caffeine acctualy do to your body in order to keep you awake?

[Assistant]
There's a molecule called Adenosine. As you go longer without rest, it builds up in your nerves. If adenosine were to dock with adenosine receptors, you would feel drowsy and tired. Caffeine comes in and docks with the adenosine receptors, preventing actual adenosine from binding to them. No binding = no sleepiness and more alertness.

Over time the caffeine you have is metabolized or gotten rid of, and you get tired again.


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

[User]
[Star Wars] Why didnt the First Order just send TIE Fighters to destroy the rest of the Resistance ships?

Kylo and two TIE fighters destroyed an entire cruiser by themselves. With an entire fleet of Star Destroyers, including Snokes personal ship, they should have had enough TIE fighters to turn the rest of them into space dust as opposed to firing from a distance and waiting for their fuel to run out.

[Assistant]
The reason they pulled Kylo and the other fighters back in the first place is that the Resistance had pulled enough distance that the cruisers couldn't support the fighters any longer, which puts them at greater risk.  With no powerful need to destroy them immediately rather than in a few hours, there's no reason to throw away those ships and pilots.

The other bit is that it opens up an escape opportunity for the Resistance.  If the First Order launches fighters, the fighters make the transit to the Resistance ships, then the ships jump away, the First Order has to recover fighters before they can jump as well.  That gives the Resistance a window of time in which to make a second jump and break the hyperspace tracking lock.

Now they couldn't actually do that because they were too low on fuel for two jumps, but the First Order didn't know that for sure, and so had to take that threat into consideration.


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

[User]
[Star Wars] What would have happened if Luke Skywalker had joined Darth Vader to kill the emperor and rule the galaxy together?

I've always wanted to see this in the movies even though it would mean Luke would fall to the dark side or Vader would come back to the light.

[Assistant]
Striking down the Emperor in anger and in the quest for power completes Luke's fall to the dark side. He is probably severed from the force ghost advice of Obi Wan and Yoda, and gets real dark as Vader's apprentice.

Things start as a standard master-apprentice affair between Luke and Vader. The presence of the dark side and the corrupting influence of Sith training erodes anything resembling a father-son relationship.

Like Vader did under the Emperor and like the Emperor did before him, Luke trains secret Sith apprentices and Vader does the same. Luke probably wins, assuming his eventual Jedi Master strength level translates to Sith Lord power. Luke rules in the place of the Emperor.

With his new apprentice, he consolidates power and rules as he sees fit, which is likely to establish rule by the power of the Force. Luke probably doesn't keep the anti-human prejudices of the Emperor, in which case the Empire becomes more inclusive. Still, it's rule by force and strength, it's a dictatorship, and Luke's rule bears all the trademarks of any other Sith rule.

It's not the worst outcome for the galaxy, but certainly not the best.


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

[User]
[ASOIaF] What if Renly Baratheon took the throne?

Renly wipes out Stannis, marches on Kings Landing with his massive host, seizes the city and takes the throne. How will the War of Five Kings play out?

[Assistant]
I believe he had agreed to let Robb remain King of the North, didn't he? So, once Renly took the south, he'd be just sort of done. Robb would've been able to focus on the North.

I think the Greyjoys hadn't invaded at the time Renly was killed. If there was no war to distract Robb, and no reason to send off Theon to get an alliance with Balon, there would've been no war in the North. Even if so, if Robb's host had been at Winterfell, it wouldn't have been sacked.

It's hard to say what would've happened with the Freys. Robb may have gone through with his marriage contract (he met Jane Westerling on the field of a battle that wouldn't have happened), or he may have met her elsewhere or met somebody else and fucked it up anyway. However, without the war, Robb wouldn't have been in a position to get himself killed regardless, and the Lannisters wouldn't have been there to back the Frey in Robb's killing. So breaking a marriage contract would have had little impact on the anyway.

Only question is whether the realm would be any better prepared for either Dany or the White Walkers when those come into play. (I haven't gotten that far in the books yet, incidentally)


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

[User] ELI5: Why do sapling trees not lose their leaves in the winter while adult trees of the same species do?

[Assistant] Some like beeches hold onto dead leaves to collect snow at their base for added water when it melts. Saplings in general hold onto their leaves longer than the larger trees to get some last minute sugar from the sun without the shading of the larger trees.


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

[User] ELI5: why is it that things like ribbons curl up when dragged up against a sharp object like a scissors?

[Assistant] Imagine folding a piece of piece of paper in half, then opening it up.  The crease down the middle remains, and the paper no longer lies flat.  Imagine creasing the paper once every inch across, now it will curl up a bit.  When you drag a ribbon across a pair of scissors, you are creating one continuous crease.  This makes it curl up!


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

[User]
[Star Wars] Had Anakin Skywalker never been burned and used the suit, would Luke learn of his identity much earlier?

So after the Obi-Wan and Anakin battle, Anakin is left burned and near limbless. This prompted for him to have to use the iconic Darth Vader respirator suit.

Luke eventually learns of his heritage later on...and the rest is history.

However... what if things went differently??

**SCENARIO:** Obi-Wan manages to knock Anakin out and leaves on the ship. He drops the babies off to their respective future homes. Anakin wakes up, somewhat humbled but furious. But he continues his path , secretly, as Darth Vader.

Anakin now does not need to hide his appearance and keeps his full name for the public.

Luke grows up and notices this man on the news who he looks strikingly similar to, especially in the eyes and hair. Not to mention, they share the same last name. And he starts asking questions.  Will he learn early on? Who will tell him? Would it change anything?

[Assistant]
We know from Legends that Sidious was grooming the public perception of Anakin to be a post war hero. he was publicly seen as the only good Jedi, the one who did what had to be done, while not letting the Meek suffer needlessly. what's more after his assault on the Jedi Temple he effectively crushed a Jedi coup d'etat and saved not only the republic but the chancellor. Anakin losing large portions of his body mass, as well as his defining features was a terrible loss to the Sith cause. it's severely weakened anakin's connection to the force and effectively demolished all previous work done by Sidious towards the perception of Anakin. if you read the Darth plagueis novel it would be a similar master apprentice reflection of the book, we're Sidious was the background master puppeteer, and Anakin was the political Poster Child for the postwar era.

If Anakin had retained his Skywalker Monica, then it's entirely possible that through Imperial propaganda of anakin's face, and the extremely well known name of Skywalker, that the idea may have cropped up to young luke.


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

[User]
ELI5: Why is space black?

Why is space black?

[Assistant] Color comes from light, light directly from a source or light reflected/scattered off a surface. where there is no source or no surface there is no light. Space is a vacuum so there is no source and there is no surface, so there is no light in space. That makes space black.


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

[User]
What happens to electricity pushed onto a grid beyond that grid's capacity to use it?

With the ascendancy of renewable or otherwise privately generated electricity, many electric companies allow electricity produced in excess of private use to be 'pushed' back onto the wider grid, even paying for that generated electricity in many cases.  It makes sense to me that, most connected users being net-electricity-consumers, whatever electricity I push onto the grid is just used by someone else connected to the grid.

My question is, what happens once private generation exceeds grid usage?  Where does 'unused' electricity go?  What method or mechanism is used to shed excess energy in an electrical grid?

[Assistant]
The grid is composed by several sections that can be opened, closed and rerouted to match supply and demand without putting too much current in the grid. If you put too much current elements of the grid would fail (transformers, breakers, even cables that could melt).

Depends on where the electricity is coming from you can disconnect that section not to overload the rest of the grid. The same can be done with demand (if an area is pulling too much current it could bring the rest of the grid down).

Grid management will make sure that excess current is disconnected from sections that can't support it. With power companies those loads are negotiated every morning and planned carefully during the day.

With home generation that production can also be predicted but contrary to the power plants, that current can't be disconnected easily, at least not without causing at least some local issues.

So there are two methods, either you get power plants to reduce production (which is not that a fast thing to do and after the bidding is done in the morning prices are already set) or you disconnect other big renewable generators (wind, and solar farms). Those can be disconnected from the grid and the energy is just lost to heat.


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

[User] [Wicked] How on earth can Fiyero fall in love with Elphaba so quickly and want to lose his life for her when they only knew each other for a semester or 2?

[Assistant]
2 semesters is nearly a year, so that's a reasonable amount of time to know someone.

Elphaba was the first person in his entire life to truly challenge him. Look beyond his looks and actually care who he was. In a sense she was the first person to ever know him.

Also he was a vapid teen up until then, so let's not be so surprised that he was ready to do something so dramatic.


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

[User] [DC (Green Lantern/ Superman)] do you have to have permission from a kryptonion to send someone to the phantom zone? Could Hal Jordan, or any of the other lanterns, send a villain to the phantom zone?

[Assistant]
I think Superman's got the only Phantom Zone doorway so you would have to ask his permission to use it.

Or sneak/break into his Fortress. Good luck with that though. You'd have a tough time just lifting the key to the front door, let alone getting past the robot butlers.


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

[User]
[LotR] How old can Orcs get?

Assuming they weren't murdered, or fell ill from poison or disease?

[Assistant]
> They could be slain, and they were subject to disease; but apart from these ills they died and were not immortal, even according to the manner of the Quendi; indeed they appear to have been by nature short-lived compared with the span of Men of higher race, such as the Edain.

~Morgoth's Ring "Myths Transformed"

So they weren't immortal, and were apparently short-lived compared to Men of "higher race". What does higher race mean in this context? Tolkien mentions the Edain, but the Edain of the First Age had an average lifespan of 70-100. The problem with Orcs living shorter lives than the original Edain is that we have one documented lifespan of an Orc: Bolg. Bolg's father, Azog, was slain in 2799 TA, and Bolg himself was killed at the Battle of the Five Armies in 2941 TA. So Bolg must've been at least 142 at the time of his death, which means that either he was just an exceptionally long-lived Orc or that Orcs live longer than the Edain of the First Age. So in that case, Tolkien might've been referring to the Numenoreans, direct successors of the Edain. They lived 200-400 years, depending on their bloodline, so if Orcs are living to around 150, then they would be "short-lived" compared to the Men of "higher race".

So in other words, Orcs could live to the age of 140+, but they probably didn't live much longer than that. And it's likely that few Orcs actually made it to Bolg's age, considering the violent nature of Orcish society.


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

[User] eli5: why aren't more portable devices waterproof by now? It seemed like the direction things were going a few years ago.

[Assistant]
Extra cost combined with not much need.

Its a handy feature to have when you need it, but for the most part people aren't trying to use their devices in the rain/water.

Waterproofing all of the seams and openings takes extra time and effort which makes manufacturing more expensive and complicated.


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

[User] If Deadpool can break the 4th wall and change continuity, does that make him the most powerful Marvel character of all time?

[Assistant]
After a character breaks the fourth wall, it's no longer the character's "power level" that matters but the writer's. And the writer always has less power than the company.

For example: the writers on DC's "Batwoman" wanted the titular character to marry her girlfriend, but DC editorial didn't allow it. The marriage didn't happen because editorial is more powerful than the writers.

Deadpool loses all power in the presence of an editor. By the metric of "continuity changing aptitude = power level" the most powerful character in the Marvel Universe is the Editor-In-Chief Axel Alonso. Deadpool can't do anything without Alonso signing off on it, and Alonso can authorize the erasure anything Deadpool has ever done.

However, Alonso is beholden to something even more powerful. Not a character, but a rule. The Math. A book's sales are too low? The math says the book is cancelled. Sales go up during giant bloated annual crossovers? The math says they have to do crossovers.


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

[User] I read that all the cells in your body are completely renewed every decade or so. If you have a transplanted organ, how does the body replace its dying cells?

[Assistant] The cells of the transplanted organ will divide and replace themselves, just like the rest of the organs in your body. The transplanted organ will still be made up of cells 'from the donor' 10 years later. They will never be replaced 'by your own cells'. That's why transplant patients need to take anti-rejection drugs for life.


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

[User] ELI5: What is the deal with Asian people always squatting down to do stuff (eat popsicles, smoke cigarettes, etc.)?

[Assistant] Before the invention and wide distribution of the chair, everyone relaxed like that. A life time of sitting in chairs will make your hamstrings, and the muscles and connective tissue in your thighs, calves, and lower back less supple, to the point of making squatting uncomfortable or even painful. In parts of the world where chairs are less common, most people squat to relax or socialize. Chairs are bad for you. In Japan people traditionally sat on the floor at a low table to eat their meals; watch a traditional Japanese family sit down to dinner and see 80 year olds easily fold their legs under them and sit down.


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

[User]
CMV: Reason is, and ought only to be, the slave of the passions.

The title of this post is a famous quote from the Scottish philosopher David Hume.

Hume's argument, which I think is correct, is that reason alone cannot be an effective guide to human action, because only through "passions" which are Hume's terms for emotions and desires, do we have motivation to act.

That is, in the Humean worldview, reason is an instrumental tool which is only useful when given a motivating direction by passions, which exist independent of reasoned thought.

It has been a while since I read Kant or any of the a priori reason arguments he made, and I am looking to see if I'm missing something from them, or perhaps an argument I have entirely not considered.

[Assistant] The problem is that we cant really distinguish the two. Reason and passion are just combined cognitive processes - youre not just rational or emotional, youre always both. Thus trying to say one precedes the other is a bit like saying cart before horse when in fact its just a horse.


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

[User]
CMV: being fat is an eating disorder too. (TW)

Discard from that simplified statement the obvious outliers, such as those with thyroid issues or other health impediments.

We drink water when we are thirsty, we don't obsessively binge water (again, ignore conditions like diabetes which have a physiological effect on thirst).

Food should be no different. We have energy requirements, so we should eat to meet our bodies' needs.

Excessively counting calories and starving ourselves in order to hit arbitrary weight loss goals, or even good goals in an unhealthy manner, is rightly considered to he an eating disorder. The damage it does to our bodies is immeasurable and well documented.

Similarly, eating obsessively in such a way that we overstep the guidelines our native appetites naturally impose on us is a form of eating disorder.

The prevailing narrative right now is about body positivity, which is quite a noble one. Nobody should be bullied or harassed for their bodies. However, a harmful consensus has emerged where we are now discouraged from speaking negatively about the state of being fat, partly out of fears that we will induce eating disorders in people as they attempt to lose weight.

This fear of calling a spade a spade normalises the deadliest and most common eating disorder in existence right now. We shouldn't be afraid to call being fat an eating disorder in case it causes in an inverted eating disorder.

[Assistant] No it's not really. Grocery stores didn't exist in the natural environment humans evolved in and where all these eating behaviors come from. Your brain wants you to take every opportunity to sit on your ass all day and eat ice cream, because in nature it thinks this is going to be a rare occurrence and you will have to go back to failing to hunt deer tomorrow and that extra fat will help you survive.


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

[User]
ELI5: Why is it when I move my cursor to the right of my screen, it disappears, but to the left it stops at the edge?

Similar question for up vs. down.

Edit: Has to be the fastest answered question ever.

[Assistant] The actual position of the cursor is at the end of the point. That position stays on the screen - on the left, that doesn't allow any of the rest of the cursor (which extends to the right) to fall off the screen, but on the right, the actual position of the cursor can be on-screen even when most of the image is not.


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

[User]
eli5: How do your lungs filter out dust in the air?

I was cleaning out an A.C. Units air filter and it got me thinking. We breath in the same air so how do we clean out our filter?

[Assistant]
Naturally, the hair in your nose doesnt get everything. Big things, like grit or dirt will get caught in your mouth or throat, finer particles will get stuck in membranes further in your lungs and coughed back up as mucus. We catch and spit up most.

When it comes to work, If you can see it in the air, you are breathing it and need a mask. If its a manufactured material, it likely contains toxins you wont cough up.


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

[User] Eli5: why do we not use tooth filling to fill gaps between teeth and eliminate need for flossing?

[Assistant]
Your lower jaw and skull are flexible, and your teeth shift with each bite.

If you connect each tooth to each other with fill material, it would crack them with each movement of your jaw.

Braces are something that take advantage of this by connecting each tooth with strong ductile wire that causes teeth to shift more, and in a restricted direction, with each movement of the jaw.


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

[User]
How come when I chew speariment gum and then drink cold water the water feels so cold that it hurts my throat?

It's really painful and I hate it. What gives?

[Assistant]
At the heart of the minty matter is a protein called the transient receptor potential cation channel subfamily M member 8 (TRPM8), which is expressed in sensory neurons. TRPM8 is an ion channel, a type of protein that regulates the movement of ions across the membranes of cells. Just like only certain keys can open a lock on a door, only certain stimulants can open the ion channel and access the cell. TRPM8 opens in the presence of cold temperatures and allows Na+ and Ca2+ ions to enter the cell. This changes the electrical charge within the neuron and the information being sent from the neuron to the central nervous system, eventually leading to the perception of cold.

TRPM8 doesnt just respond to cold temperatures, though. It also activates in the presence of menthol, a waxy, crystalline organic compound found in peppermint and other mint oils. (It responds to other cooling agents, too, like eucalyptol and icilin. Why, exactly, is unknown; menthol just happens to fit the cellular lock.) In the presence of menthol, TRPM8 ion channels open up the same way they would if the ambient temperature in your mouth dropped. The same hey its cold in here! signal is sent to the brain, even though menthol doesnt actually cause the temperature in the mouth to change. And just like that, the wondrous human brain is tricked by a piece of Doublemint.

Even after you spit the gum out, a little menthol will remain and the sensory neurons will stay sensitized. Drinking anything cold or even taking in a big breath of cool air will cause the neurons to fire again, and the double whammy of the cool temperature and the menthol will make your mouth seem extra cold. Even a hot drink will seem weirdly cool and refreshing.


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

[User]
ELI5 what happens when lightning strikes and the power goes out for a minute or two then comes back on.

It obviously affects the power grid but how does it get fixed so quickly.

[Assistant]
There are grid protection systems, basically big versions of the circuit breakers you have at home, that can be tripped by a lightning strike or other events during a storm.

These big circuit breakers are smart enough to check to see whether there is still a problem (tree on a line or something), or if the problem has gone away (if nothing was damaged by the lightning). If there is no problem anymore, the breakers will close themselves automatically.


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

[User]
Are there any particles that are not affected by gravity?

 And how would scientists go about detecting them?

[Assistant]
No, there are not, and it's actually quite easy to see why.

Gravity is the observed fact that things fall when dropped. This observed fact is a *consequence* of the fact that the geometry of spacetime is curved.

Any object cricket ball, electron, hypothetical magic leprechaun particle moving through spacetime will, well, *move* through *spacetime.* Therefore any object will move along trajectories that are determined by the underlying geometry of the region of spacetime through which they move. Therefore everything falls.


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

[User] [Harry Potter] What would happen if the Wizard community of one particular country decided enough was enough and they would no longer abide by the statute of secrecy, the country's magical authority deciding it was time to publicly out themselves?

[Assistant]
The International Confederation of Wizards didnt intervene in Britain when Voldemorts forces were blowing up bridges and setting giants loose in villages. Voldemort was demonstrably a terrible threat to the Statute of Secrecy, and yet they did nothing when he seized control of the country. Why? Well, because they are a bloated, toothless beurocracy, as you would expect from any large international organization.

While they would certainly oppose any country trying to reveal magic to the world, theres no way they would move quickly and decisively enough to stop it.