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

[User]
Do all wavelengths of the electromagnetic spectrum travel at the same speed?

I keep hearing speed of 'light'. This made me wonder if it is visible light that is being referred to or just any type of electromagnetic radiation?

[Assistant]
Many of the answers so far correctly state that the speed of light *through vacuum* does not depend on wavelength.  In materials, however, this is not the case.  In matter, different EM wavelengths will propagate at different speeds, this effect is called dispersion.

The two parameters that govern the speed of light are the electric permittivity (epsilon) and magnetic permeability (mu) of the medium the light is traveling through.  *You can loosely think of these two parameters as describing how much the medium resists changes in the EM field*.  The vacuum permittivity and vacuum permeability are not dependent on wavelength, and so the speed of light *in vacuum* is also not dependent on wavelength, and so all colors of light travel the same speed in vacuum.

**However**, when light travels through a material, the speed of light *does* depend on wavelength (though we should really be thinking in terms of frequency, with the understanding that wavelength and frequency describe loosely the same attribute of the optical wave).  Materials are made up of charged particles which can interact with the optical wave that is traveling through the medium.  Remember, electrically charged particles have their own electric field and will be pushed around by the electric field of the optical wave, this impacts the electric permittivity and magnetic permeability of the material, so the speed of light in a material will be different than the speed of light in vacuum (since there are charges that the EM wave can push around as it travels through the material).  You can think of each electron as being attached to springs - the incoming EM field can then interact with the electrons, pushing them back and forth.  Continuing with this analogy, the speed of the EM wave depends on how 'stiff' the 'springs' are.  In reality, the 'stiffness' is simply the electric permittivity and permeably of the material.  These two parameters depend on the material, as well as the frequency of light - that is, a low frequency wave will drive the electrons back and slowly while a high frequency wave will try to drive the electrons back and forth faster (sometimes so fast the electron's don't follow the EM field very well).

The index of refraction of a material is related to the permittivity and permeability of that particular material.  More commonly, we use the index of refraction to describe how fast light travels in a material.  The phenomenon you describe in your question is called *dispersion*, which is essentially wavelength dependent index of refraction.  All materials have a dispersion curve which shows the index of refraction as a function of wavelength for that particular material.

**Edit**: if you treat each electron as a harmonic oscillator being driven by an external force, you see that the motion of the oscillator depends on the frequency of the driving EM field. Since the electrons are being driven by the incident wave, they themselves create an EM wave. In fact, using this model, the incident wave is absorbed and the wave that propagates through the medium is a result of how the electrons move - which is frequency dependent (it's also dependent on the shape of the potential well the electrons find themselves in due to their neighbors).


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

[User] [LOTR] Isildur had some magical abilities, which is how he created the Army of the Dead. Do his descendants (Aragorn, Boromir, Faramir, etc.) have any magic of their own?

[Assistant] I think Isildur cursed the Army of the dead with just calling them out on not fullfilling their Oath which had supernatural power, so by not doing what they promised it allowed supernatural powers of the world to curse them. So he didn't exactly create the army with magic, magic just existed in the world.


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

[User]
CMV: For environmental reasons it should be acceptable and even respectable to wear old, worn clothes

The production of clothes consumes resources and generates pollution. Hence one of the things we can do to protect the environment is to buy less new clothes and use our existing clothes for longer. I am not interested in discussing what fraction of our environmental footprint this constitutes. This is just one of many things we can do to help the environment, and every little thing helps.

Unfortunately this is not always socially acceptable. Wearing worn clothes looks like a sign of poverty and can get you discriminated against. This is perhaps especially bad in a professional environment. Customers and business partners can be unwilling to do business with someone whose employees dress like poor people. This is incentivizes employers to pressure their employees and prospective employees to dress up. This is a negative-sum arms race that harms the environment.

We should not discriminate against people who wear worn clothes (within reason). Instead of assuming that the person is poor or lazy, it is better to give them the benefit of the doubt and assume that they might be environmentally conscious.

Fancy new clothes should be thought of as a luxury, not a social necessity.

The environmental benefit may be small, but it is still worth it.

**EDIT 1**: I've given a delta already for the argument that it's good to buy quality clothes that last longer.

**EDIT 2**: Some people seem to think that I am trying to outlaw new or fancy clothes. That is not what I said. I just want it to be socially acceptable to wear clothes that are neither new nor fancy.

[Assistant]
You can wear old, used, and/or repaired clothing and still look respectable.  Plenty of people do, but you probably dont really notice them because they dont look like they are poor.

Dress nicely is usually more about being deliberate about how you present yourself to others than it is about acquiring the latest fashion.   Thats *easier* by just buying new clothes than by keeping old clothes in use, but its not necessary.

Go to some thrift stores or consignment shops, look for some basic clothes that fit you well, and no one will think twice about your clothes.

The biggest problem is that people buy cheap clothes, which wear out faster and are harder to repair.  So the core problem is not that its unacceptable to wear older clothes, its that people dont want to spend the money up front on clothing that will last a much longer time.


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

[User] [It] Is It depressed or a bum? If It is an interdimensional powerful being, why is It content to stay in Derry and more so in the sewers where it gets covered by everyone's excrement?

[Assistant]
From what I've read from other people asking a similar question.

Low hanging fruit and big fish small pond.  Basically Derry is a good thing going for Pennywise, it's small and out of the way, nobody really does anything to stop him or seem to be even aware of his existence past calling the town cursed, people live there and kids are there.

It's just easy living.


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

[User] [ The Walking Dead] How many people saw their loved ones wake up as Walkers during the funeral?

[Assistant] Probably very few if any at all. The zombies are caused by a virus which would need a living host to work. Its possible that somebody contracted it right before they died, but by the time a funeral happened a few days later they would have woken up already.


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

[User] Can you get Vitamin D from the Sun passing through a window?

[Assistant]
Normal soda lime glass (used in almost all windows) transmits no light under 350 nm. Optimistically, Vitamin D synthesis takes place at 280 - 310 nm, with an optimum at 295 nm. This means no measurable vitamin D synthesis through windows.

However, there are also applications of borosilicate glass in modern architecture, which is clearer, stronger, more heat resistent and ofcourse, much more expensive than soda lime glass. Borosilicate glass transmits around 30% of the emitted light at 295 nm. So through borosilcate glass you will form vitamin D, but more slowly.


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

[User] [KingArthur2004] in the movie's timeline the western Romans stay in Britain an extra 57 years, into a time when they were effectively limited to just Italy in our history. What were they doing right in that reality that they did wrong in ours?

[Assistant]
One of three things, probably.

A) The Huns didn't invade or invaded less in the late 4th century (maybe there was a plague that reduced their numbers for a generation or two), which means that Germanic tribes didn't flee/migrate towards the Roman Empire at that time, avoiding the resulting eventual animosity and lootings and sackings until later in history.

B) Someone, somewhere, didn't lose a battle, resulting in more experienced Roman troops still being around or alternatively there was an upswell in patriotism (or money, see option c) that meant more Roman citizens were recruited into the army, thus avoiding the military recruiting a lot of non-Roman mercenaries who would backstab Rome at the first opportunity. Again, this problem of not enough loyal soldiers was probably just delayed rather than mitigated, resulting in Rome holding on for a while longer but still going down.

C) Economy. Someone didn't embezzle as much, or an expensive war wasn't fought (leading back to option b with more soldiers surviving), and the Empire had more money to pay their armies and keep everything in order for a couple more generations. Corruption would always have the potential to take down the economy later, but it might have been delayed a few decades if the right group of people weren't grafting the system at the right time.

Or maybe something else. But it usually boils down to economy or skilled manpower.


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

[User]
Since the speed of light is finite, how do we know that the galaxies shapes are really the way they appear?

For example, the Andromeda galaxy is not situated perpendicularly to Earth, so the light from its northernmost point takes longer to reach us than the light from the southernmost one, which surely creates some distortions?

[Assistant] It does, but it's small and we can account for it when necessary. Galaxies are on the order of ~100k light years in diameter and rotational periods are on the order of ~100s of millions of years so it's a minor effect.


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

[User]
How important is your advisor's name?

I've been working with Professor V. for a few months now, and it's going really well.  We get along, I like the problems he's giving me, and he seems invested in my work.  He's sufficiently well known and well funded, and his students have in the past gotten modest post-docs.

There is another professor in the department, Prof C., who works in pretty much the same area and is one of The Big Names.  He has many students, is out of town a lot, and has gotten students into very prestigious positions after graduation.  I've never spoken to him.

Now Professor V is pressuring me to enter candidacy, he says my work is going very well and I should get started on a dissertation soon.  I'm worried that 10 years from now I will look back and say "I had the opportunity to work with Professor C, why didn't I take it?"  But my option now is to put the brakes on my work with Prof V, and spend this spring working with Prof C, perhaps only to decide we don't get along and end up back where I am now but one year older.

So I ask, how important is it to work with a very prestigious name if you have the chance?  I want to continue in academia, will my career 20 years from now be affected by having worked with a Nobel laureate?  I know my friends and I talk a lot about "this speaker worked with Andrew Wiles, she must be a genius, we should go to her talk" but do professors feel the same way, or is that just because we are young and only know the big names?

[Assistant]
Well. Working for someone famous is not insignificant. There is the direct benefit of name recognition, as you pointed out -- having a famous, respected name on your CV will make it stand out.

There are also fringe benefits. Famous people tend to get more funding and have a better network of people who are eager to do them favors than non-famous people.

But, as you point out, you already have a good working relationship with this other person. So is there a way to have the best of both worlds? Can you do your degree under Prof. V, and include Prof. C on your committee and as a co-author on a collaborative project or two?


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

[User]
[DC] Are the people of Gotham aware of when a change in Robins takes place?

I imagine that it's hard to get a good look at Batman or Robin, so with the changes between Dick Grayson, Jason Todd, and Tim Drake would there be a notable difference? Damian Wayne and Stephanie Brown would seemingly be obvious but the others are all fairly similar in appearance and stature, or at least similar enough so that you wouldn't be able to tell the difference between them when in action.

[Assistant]
Hell, they aren't even sure that the Batman is always the same. There are a lot of people who are *sure* that Batman is actually several different people. The same goes with Robin. When Robin started making his way to Bloodhaven the same thing happened there.

So they end up thinking its fairly probable that they aren't all the same. But the people understand something that is fairly difficult to. Whoever's Batman doesn't matter, its about the title, the mantle.


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

[User] Why does water break electronics?

[Assistant]
Water only damages electronics if they are being powered. If you took your cell phone battery out, dropped the phone into a barrel of water, and then dried it out completely it would still function perfectly.

The reason why powered electronics get damaged is because water is a good conductor of electricity. The water will bridge circuits together and they will short.


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

[User]
[Star Wars] When did the stormtroopers stop being cloned and start being recruited?

In a recent episode of Rebels and in the new teaser trailer it seems that stormtroopers are no longer clones, but rather recruited and trained.  When and how did this happen?

[Assistant]
In the Legends Universe, there was a clone uprising on Kamino about twelve years after Chancellor Palpatine announced the restructuring into the Empire. After that they stopped using Kamino-grown clones.

In the Clone Wars, it's mentioned that Jango Fett's DNA that they had was deteriorating, and wouldn't be sustainable.


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

[User]
ELI5: Why do dogs continue barking unless told/yelled at to stop?

So during the night whenever my dog hears a noise she will start barking and continue to bark even if there are no more strange noises. If I go and yell the command that she knows to be quiet she will settle down (eventually bark again when she hears another noise) but if I don't say anything she can continue barking for 5min+. Why is this? Is she barking to let me know of something and me saying quiet is letting her know it's okay/has the behavior for someone to say something been enforced? Some nights I have had to resort to physically hitting her bottom because she would just not shut up. I don't want to get a bark collar in fear they will never bark again.

[Assistant]
I believe it is because we have been breeding them that way for thousands of years.  Think of them as the poor man's intruder alarm.  Dogs that alert their owners to perceived danger should continue barking until told that it is okay.

I also understand that wolves do not bark (or bark much) and this is the reason why.


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

[User]
[Marvel/DC] What would Ironman's Batman Buster armor consist of?

Tony Stark has specific armor to fight specific people, Hulk Buster, Thor Buster, etc. what would he design to fight the Dark Knight?

[Assistant] Just a regular iron man suit that plays the holographic video footage of Bruce Wayne's parents dying over and over again on loop, and finally when Batman finally snaps. It'll play the rick roll video just to rub salt in the wound.


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

[User] ELI5: if atoms are almost completely empty space and I am made up of atoms, then what is stopping me from walking through walls if the empty space lines up right?

[Assistant]
Electromagnetism! The electrons in the atoms of your butt repel the electrons in the atoms of the chair beneath you, so you don't fall right through it.

It's not a question of "if the empty spaces line up", the empty spaces are almost always "lined up". You cannot fathom how tiny electrons and nuclei are and the vastness of space between them, every picture you've ever seen exaggerates their size. If a proton is a pea, then a hydrogen atom is a football stadium, and the electron is a grain of sand somewhere in that stadium. But the proton and more importantly, the electron have extremely powerful (relative to their size) electric charge.


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

[User]
[Marvel] If SHIELD stands for Strategic Homeland Intervention, Enforcement, and Logistics Division, what are the other Divisions?

I know that the name has been different in the past, but I know this is the current name in the MCU and I believe it is the current name in the comic book universe (616) but they don't say the full name all to often so I'm not sure. Anyway, the name is phrased so it sounds like SHIELD is just the Intervention, Enforcement, and Logistics Division of a larger organization having something to do with "Strategic Homeland."

So, what is this organization that SHIELD is a division of and are there other divisions?

Just for the record I do know about SWORD, but that doesn't seem to be the same organization because of the fact that "Strategic Homeland" is not a part of the acronym.

[Assistant] First off, 'Strategic Homeland' isn't an organization, it's a coupla terms slapped together. 'Strategic' because S.H.I.E.L.D. is involved with a lot of strategizin' (alternately 'because it sounds good'), 'Homeland' = 'the good old U.S. of A.' S.H.I.E.L.D. breaks down as such: 'Strategic' 'Homeland' 'Intervention, Enforcement, and Logistics Division'. What that boils down to is that someone really wanted the acronym to spell 'shield'.


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

[User]
CMV:If Biden gets nominated, nothing will change/get better

Im not participating in this cycle of lessor of two evils. Biden sexually harasses women on live TV. Hes a creep. He is just as dumb as trump, if not dumber. Hes bland af. And offers us nothing but the status quo, which if you havent noticed, fucking sucks. Were pretty much all done with this game. We need change. Some people working 2 jobs and still cant break even. Going broke for a dr visit? Thats insane. I cant take my gf to the hospital or she will pay 500$ copay unless admitted long term. She has a masters degree and 4 state  licenses but only makes 48k a year in NYC which is nothing. +80k in student loans which are getting larger even though we pay them. Those of us who are college educated have been cursed from birth to bare the student loan burden. Out of those who dont have a job, honestly, no one wants to work anymore because there's honestly no point in even trying to win the Red Queens Race. Were drowning in debt. Were getting absolutely slaughtered out here. No one is helping us.  We will do something if nothing is done.

[Assistant]
No matter how uninspired you are by Biden, consider the next presidents influence on the supreme court. Trump and Biden will have very different ideas on how to replace RBG if she passes away or retires in the next 4 years.

If trump is reelected, you're crippling potential liberal bernie-style agendas potentially for decades, even if you succeed in electing someone like that in 4, 8, 12 years or whatever.


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

[User] ELI5: When dealing with emotional trauma like the death of a loved one, or a breakup, why do emotions quickly oscillate between deep sadness and acceptance?

[Assistant] It's like this. Let's say that your computer is broken, you know it's broken, and you are sad. Same with someone else's death or a breakup, you realize it is gone, and there's nothing you can (at least immediately) do about it. When you accept, you get a small amount of time where you're alright because you know there's nothing you can do, you just have to get it over with, but then after a while, you get remembered about all the happy memories you had, and how you want them back, and you wish you could have them back again.


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

[User] [Star Wars] What do the buttons/switches on Darth Vader's chest panel do?

[Assistant] They control his suit. Its primary function is as an environmental suit, to keep the pain of the burns and the scars at bay. It's coupled with the breathing apparatus and a bit more environmental sealing in his mask to make a full environ suit to keep him safe and sterile at all times.


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

[User]
If cancer cells don't respond to signals telling them it's time to die, and thus continue multiplying until they get out of control, do they ever get genetic mutations or faulty replications themselves?

Are there any drawbacks that cancer growths have (for themselves not for the host) as a result of this uncontrolled proliferation?

[Assistant]
Yes, cancerous cells often have dysregulated mechanisms leading to increased mutation rates. If you collect a bunch of cancer cells and genotype them, youll find multiple lineages. The lineages compete for scarce resources, though, so any mutation causing cells to be less invasive or slower to divide is likely to be disfavored and result in that clone becoming extinct as more aggressively growing clones outcompete it.

People who have gone into remission and then relapse often have a cancer with changed genotype and different properties after relapse, since the re-emerging cancer is founded by cancerous cells that have a mutation that made them resistant to the chemotherapy regimen used to drive the cancer into remission initially. Usually a change in therapy is required to achieve a second remission, if possible.


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

[User]
Myth of Sisyphus

I've recently read Camus' work on this and I absolutely loved his work. I'm desperately searching for any other philosophical essays that personify the inevitable struggle of life, and how you have to accept it and move on. If anybody could direct me to something similar, it'd be very appreciated.

[Assistant] In terms of accepting the struggles of life and how to move on, this is essentially the primary focus of Stoicism.  *Meditations* by Marcus Aurelius while not an essay is a great collection of thoughts on accepting one's lot and his place in nature.


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

[User] [Harry Potter] Are spells discovered or invented? If invented, how?

[Assistant]
Invented.

The Bat-Bogey Hex was invented by Miranda Goshawk, famous for writing the Standard Book of Spells, which is basically the quintessential work used in nearly every school of magic.

The spell Sectumsempra was invented by Severus Snape.

The process for inventing spells is likely not easy, and involves a great deal of trial and error to get the correct combination of wand and verbal components in line.


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

[User]
CMV: Magneto from the X-Men Franchise would have stopped MCU Thanos easily.

To start, all you need to do to prevent Thanos from using the stones is to keep him from closing his fist. Since the gauntlet is metal, Magneto should not only be able to keep the gauntlet open, but he should also easily be able to yank it off of him. If Iron Man and Spidey managed to nearly tear it off of him, a man who moved the Golden Gate bridge from a mile away should have no issue with taking the gauntlet.

Now, if Thanos already has all six stones, he can pretty much end anyone instantly. He theoretically could destroy Dormammu if he wanted with just a snap. Therefore, Magneto loses here.

But if Thanos doesnt have all six yet, he stands no chance. Even if Thanos stripped nude to get rid of his armor, he has shown to be able to murder people just by them having too much iron in their blood. He would find a way.

Magneto buttfucks Thanos.

[Assistant]
>Since the gauntlet is metal, Magneto should not only be able to keep the gauntlet open

Only if it is a ferrous metal.  Magneto has power over magnetic fields, which means that he has zero power over objects that are not magnetic (hence the plastic prison).  We have no idea what the gauntlet is made of, but if it is primarily made out of something like aluminum, copper, lead, tin, gold, etc. then Magneto can't do anything.  Magneto is just an old dude that will get his ass kicked.

To your point about the blood, same issue.  Thanos is an alien - we have little evidence that his system uses iron to bind oxygen in his blood or uses it in a quantity that Magneto could take advantage of.  This isn't far-fetched - many animals on earth use hemocyanin rather than hemoglobin to transport oxygen - replacing copper with iron to bind the oxygen.  Copper is non-ferrous and not magnetic.

If he doesn't, then Magneto loses again.


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

[User] ELI5: Why is adopting so expensive?

[Assistant] Somebody has to pay for the hospital bills, paperwork, hours for attorney,  etc..usually the mother can't provide and the adoptee are so desperate for children they will foot any bill to get what they want.


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

[User] ELI5: How come our eyes can scroll when focusing on a moving object, but we can't casually scroll our eyes when not focusing on something?

[Assistant] The control systems for your eyes are *specifically adapted* to help you fix your vision on specific objects so you can see them. There is no advantage to being able to move your eyes arbitrarily, so the control system has no special features to make this easy.


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

[User]
[Star Wars] Other then Luke and Obi-Wan was there a Jedi who fought Darth Vader and survived or was spared.

Title pretty much sums it up. Not bothered if it's no longer cannon just curious.

[Assistant]
Yes, Ahsoka Tano fought Vader.

Although technically no longer a member of the Jedi order at that time (she had left the order previously), she fought him and survived.

ADDED: One could include Ezra Bridger as well... But he was never formally a Jedi and he only really survived because Ahsoka intervened.


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

[User] ELI5: What happens to the photons that enter your eye? Where do they go after they transfer their information into the retina? Do they just bounce back out of the eye?

[Assistant]
Photons must be destroyed to transfer any information.

They are absorbed by chemicals in the retina, their energy is used to briefly change the shape of the molecule and trigger a signal.

This generates a small amount of heat, which is why staring at the sun can overheat and damage your retina.


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

[User] ELI5: Why do people get chills whenever they see/experience something that creates a strong emotion?

[Assistant] When you experience a strong emotion, your brain sends signals to your muscles that make them tense up. When the muscles in your skin that are attached to hairs do this, they make the hairs stand up and pull your skin up just a bit, creating goose bumps (or chills). This so-called "pilomotor reflex" in animals often has the effect of making an animal look bigger. This might help to scare away potential enemies. In humans, though, the reflex has more to do with muscles. As the body reacts to fear, for example, it will often prepare either to flee or to fight the danger. This requires muscles to tense and be ready. The reflex helps to get the muscles warmed up and ready to move.


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

[User]
ELI5 why are tennis courts different materials?

Pro basketball always on wood. Pro football (US) mostly on grass. Why do tennis surfaces vary so much?

Or is it just green clay sometimes?

[Assistant]
It comes down to what is easily available and, more importantly, what is easier and cheaper to maintain.

Historically, all courts were grass. That was the natural surface available. However, in order to have a playable grass surface, it needs a *lot* of maintenance. You need the right kind of grass (and soil), and it constantly has to be mowed and kept up to standard in order to have consistency. The grass will deteriorate as the match our tournament goes on, and takes longer to dry out after rain.

Clay courts were a great alternative, especially in environments which were less favourable to maintaining grass courts (Europe, South America). With advances in materials and manufacturing, hard courts became more feasible and are commonly used for purpose-made arenas. Grass courts are maintained more out of tradition.

In contrast, football is always on grass because it is normally the most versatile surface for the sport. The quality and condition of the grass is not important, as the majority of the sport involves running and the interaction of the ball with the grass is not as important. Artificial surfaces were introduced to reduce the maintenance associated with grass. Basketball was invented to make use of gymnasiums that were already built (with wooden floors), and "pro" basketball always uses courts that are made to a specified standard. Unlike tennis - advances in technology haven't shown a need to change the playing surface.


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

[User]
[Transformers] Where did cybertron and its inhabitants come from?

Considering the autobot's and deceptions are robotic, as is the planet seemingly, something must have created everything, right? Was it some other alien species, or a god of some sort, or did it just come from nowhere?

[Assistant]
From Wiki: According to transformers lore, before the dawn of time, Order and Chaos existed within an extra-dimensional entity known as The One. To explore the fledgling universe, he created the astral being known as Unicron, and then subdivided him, creating his twin, Primus. Both brothers were multiversal singularities, unique in all realities, but where as Unicron could only exist in one universe at a time, moving between them at will, Primus existed simultaneously in all realities at once. It is suggested, in fact, that the two brothers embody the basic concepts of realitygood and evil, order and chaosand that their continued existence is necessary for the stability of the multiverse.

Where did Order and Chaos come from? Big Bang or deity or whatever you choose to believe.


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

[User]
[Mass Effect] If the Reapers eradicate all life every 50,000 years, how do dinosaurs and other prehistoric creatures fit into the Mass Effect universe?

Do dinosaurs just not exist in the Mass Effect Universe? Where did humans come from if all life is extinguished every 50,000 years? Or maybe did the Reapers just leave earth alone when they did their exterminations?

[Assistant] The Reapers target advanced races.  Their goal is to keep the synthetics (like the Geth) that the advanced races inevitably create from wiping out organic life in the galaxy.  They function like wildfires: their periodic sweeps through the galaxy destroy much, but they also make sure that the ecology of the galaxy can continue.


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

[User] ELI5: Why did Anthony Weiner get pressured to resign from office for sending some sexual pictures to people flirting with him online, when other politicians have been in all out affairs yet they retained office with no trouble?

[Assistant]
He actually tried to deny sending photos at first saying his phone had been hacked... Effectively lying to the public for a week until he could not get out from all the jokes.

I honestly think he resigned due to pressure from party leadership. If he hadn't lied at first he may have been able to bounce back.

Oh and his name also didn't help slow the media circus.


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

[User]
CMV: prisoners serving life should be given the option of the death penalty at any time during their sentence

Its one thing to give someone the death penalty, but its definitely arguable that its crueler (Id say much crueler) to give someone a life sentence. People who have life (with or without the possibility of parol) should have the option of taking the death penalty at any time. Not only is it very arguably less cruel, its still a massive deterrent-anyone whos not scared of the death penalty is probably not that much more deterred by life in prison (not that there arent exceptions). Its also less of a strain on societys resources, if that matters to you.

Edit: tl,dr; great comment summed it up, Prison should be used for rehabilitation, not torture. The death penalty is a hugely harsh punishment already. How much vengeance do we need as a society, exactly?

[Assistant]
You run into basically the same major issues with this proposal that you do with the death penalty, especially with regard to wrongful convictions.  Not everybody in prison is guilty, and some of those who are probably deserve a lighter sentence than the one they got.  You run the risk of executing an innocent person.

Since, in your post, you say people would have to volunteer for the death penalty, it's important to note that their decision would likely be made under considerable duress, and it would be difficult to account for possible coercion or mental illness.  Almost by the very nature of their circumstance, prisoners wouldn't really be able to make that decision with total freedom.


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

[User] Does a newly hatched chick have the same nutritional value as an egg?

[Assistant]
During growth, the chicken embryo is burning off some of the stored energy in the yolk and white instead of converting it to body mass.  Since they're aerobic organisms, that entails taking in oxygen from the outside, and converting some of the carbon in the egg into carbon dioxide, which diffuses out through the shell.

If we're just talking about calories, the hatchling will definitely have fewer than a freshly laid egg.


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

[User]
Tellurium-128's half-life is over 160 trillion times greater than the age of the universe. How do we find out about half-life of certain elements?

Wikipedia told me:
Tellurium-128's half-life is over 160 trillion times greater than the age of the universe.
My mind is not only blown by the timeframe, but even more by how we actually get to the point where we know how long it takes.

Obviously its not some scientist sitting it out with a chronometer?

[Assistant]
Proportions and extrapolations.

A half life is the amount of time it takes a material to undergo radioactive decay until there's *half* of it left. So if you had a 1kg lump of Te128, in bajillion years, you would have 0.5kg of Te128 and a bunch of other 'stuff' that it decayed into.

That doesn't mean that you'd have 1kg of Te128 for all that time and then POOF! a bajillion years have passed, now you instantly have 0.5kg.

If you were to take your sample of Te128 now and measure it *really, really* accurately, then wait say, 10 years and measure it *really, really* accurately again, you'd have less Te128 and some of its decay byproducts. By measuring how much Te128 you had left and extrapolating it out, you'd figure out how long it would take the entire sample of Te128 to decay by half.

That's how you get the half life.


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

[User]
ELI5: How can drug withdraw cause death?

I am aware that there are various side effects of drug withdraw such as anxiety, sweating, vomiting, diarrhea, etc. but how does drug withdraw lead to death?

[Assistant]
Abusing drugs causes a chemical imbalance in the body. Your body compensates by generating other chemicals to balance it out. So you take more drugs and put yourself more out of balance and the body reacts further.

Now if you suddenly stop using, your body is completely out of whack, sometimes fatally so.

It's like leaning into a very strong wind.  If the wind suddenly stops, you'll fall over.


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

[User]
CMV: The draft age should be 21 not 18.

EDIT: I meant age of voluntary enrollment, not draft!

This view comes from the fact that in the United Stated you cannot drink alcohol (or smoke pot) until you are at least 21. The arguments for this policy are 2 fold. First, that your brain is still developing and these activities might impair it's development, and second, that because your brain is not yet fully developed areas that dictate decision making are not yet mature. The effect of this is that people will make choices without considering the consequences, so as a result drugs need to be made illegal as young users could not make a so called 'reasonable' decision about their usage.

What this has to do with the military:

As it currently stands, you can join the military at 18, an age scientists have agreed that your brain is not yet fully mature. Is it not immoral to allow people who are apt to make impulse decisions to sign their lives away to the government? If the logic that prohibits minors from using substances holds, then it should be evident that 18 is also to young to join the military.

[Assistant]
Are you talking about the draft age as stated in your title? Or the voluntary enlistment age as mentioned in your explanation?

Because the draft is never going to be used by the U.S. except in an emergency situation ever again. Modern equipment and tactics just make unskilled infantry too useless compared to trained volunteers.

And, by definition, if it's an emergency none of your points really matter. It's an emergency. We're being invaded by huge numbers of foreign troops that somehow make it here without being detected (or aliens or zombies or something). We need warm bodies or our country will be destroyed.

As for volunteers... the armed forces *do* assess the abilities and maturity of their recruits before accepting them.

The 21 year drinking age is not embodying a principle that *no* 19-year-olds could drink without harm... it's a line we draw because there's really no mechanism to assess individual capabilities in a liquor store, and because we don't want legal alcohol being given by 18 year old high-school students to even younger ones.

And also, alcohol is *physiological* affects on maturing brains, not just ones involving judgement and ability to make decisions for yourself.


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

[User]
How does electricity heating a filament in a light become photons streaming into my eye?

I started thinking about this last night.  After a sleepless night and a significant amount of time trying to figure it out from information on the internet, I'm throwing in the towel and asking:  what is the process, from the moment I flip the switch to the time the photons hit the cornea?  What particles and forces are involved at what stages?  I'm relatively educated for a layperson, but not educated enough to construct the full flow chart:  HELP ME GET TO SLEEP TONIGHT!

[Assistant]
It sounds like you have an incandescent lightbulb.  The electricity heats the filament because the filament is resistive, so the power = I\^2 \* R.  The filament heats up to a few thousand degrees Celsius (or Kelvin;  they're only different by 273 degrees).  It gets hot enough that its blackbody emission is partially in the visible range of the spectrum.

The problem with such blackbody emission is that a lot of the energy comes out in the infrared, which is not helpful for us seeing... it just heats up the room.  This is why incandescent lightbulbs are inefficient, and you should upgrade.

Fluorescent lights put a greater fraction of their energy out in the visible.  There, a high voltage creates a current in the low pressure gas;  that current collisionally excites the atoms to put out UV light.  The chemicals on the glass of the bulb, the phosphors, absorb that UV light and re-emit it, mostly in the visible.  This "not-blackbody process" is much more efficient because much more of the energy goes into the visible spectrum.

LED lights take the energy of the electrons and "holes" on the two side of a semiconductor junction (the D, for "diode", junction), as they recombine and emit light.  By tweaking the materials, LEDs can be made to emit different colors of light.  Some even use the "phosphor" idea like fluorescent lights, to convert blue light to broad spectrum.   Again, much more efficient in terms of "fraction of light in the visible" than a blackbody radiator.

So no matter what type of light you have, a current is being processed into photons, via some kind of fun physics.


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

[User] ELI5: Most materials can be turned into liquids at the right temperature, even rocks. Why can't wood?

[Assistant]
Not all rocks *can* become liquid. At least, not without a fundamental change in their material. Like limestone. Carbon can't normally become a liquid, for a non-rock example.

Limestone and wood both break down at high temperature. The bonds within their molecules cannot hold together when they are vibrating too aggressively. Almost all molecules encounter this eventually, but some encounter it before they are able to melt. This is especially common for things with long carbon chains in them, like flesh and plastics, since these chains can't always easily slide past each other to melt, but their bonds are relatively weak compared to the bonds of other materials like ceramics.


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

[User]
Why is Zinc more electrically conductive than nickel, and why is nickel more electrically conductive than iron?

I observed that in the 3rd shell of Zinc there are 18 (full), while in Nickel there are 16, and in iron there are 14.  Does this mean that the lower number of electrons in the 3rd shell = more electrical conductivity?

[Assistant]
Electrical conductivity is a property of condensed matter, and it is influenced by a vast number of phenomena, much more than the amount of electrons surrounding a nucleus.

At the microscopic level metals are crystalline, the atoms are stacked orderedly in arrays (crystalline lattices) whose shape is determined by the symmetry class. Different materials may have different crystalline form.

What happens to the atomic orbitals, when you put several atoms close together regularly as in a crystal?

In metals, the outer electron shells of the atoms overlap enough to give rise to composite "super-shells" called conduction bands. They are spatially de-localized (spanning the entire crystal) and are only partially filled with electrons, so that even a small electric field can give a bit of kinetic energy to the electrons in it, having them move.

Conversely, in insulators the outer electrons go into the valence band, completely filling it, while the conduction band is empty. There is a significant energy gap between the full valence and the empty conduction band and electrons cannot accept energy because they have "nowhere" to go, energetically speaking, being held back by Pauli exclusion principle. Only when the electric field is really strong they may jump from valence to conduction, this is the so-called "dielectric breakdown".

Back to electrical conductivity, different metals may contribute more or less electrons to the conduction band, the more the better.
But then you also have to think about what may disrupt conductivity:
 the electrons in the conduction band are able to "collide" with the imperfections of the crystalline lattice. The main ineliminable source of those crystalline defects is given by the thermal vibrations of nuclei around their rest sites: a nucleus being displaced amounts to a temporary electric charge that may attract or repel the electron, changing its momentum.

So, in general, electrical conductivity is a non-trivial phenomenon somewhat affected by atomic properties (the number of electrons in the outer shells), but principally determined by how the single atoms stick together (as a crystal) and by how the crystal properties, such as temperature, affect the dynamical behaviour of electrons in the conduction band.


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

[User]
ELI5:Cubesort

How does cubesort work? I was reading about other sorting algorithms when I came across Cubesort, and I can't wrap my head around it. I know how other sorting algorithms such as Quicksort, Radix sort and Mergesort work.

[Assistant]
A standard balanced binary search tree (lets say of numbers) has a root node (avalue at the very top of the tree that should be directly in the middle of our sorted data) with two branches. You compare your key to the root and go from there if its higher or lower. You keep comparing until you find your exact key or nothing. Each comparison cuts your search space in half. (O(log(n)) average time for non-ELI5)

Cubesort is a two-dimensional array of arrays, so like a grid where each square is a hole you can put your numbers in. Say we use a 4x4 grid, or 16 holes. Your key is used on the x-axis to determine which column we can find it in. Then it is used on the y-axis to find the specific square. Within that slot (remember, grid of holes) is where we will find what we are looking for, if the value exists. In here is also approximately 4 sorted values to look at. Overall, 6 lookups for 64 spots (or O(log(n)))

Why is this better than our binary search tree? We dont need to keep pointers to the various branches all over the place. Some operations are also quicker (O(log(cube-root(n))) instead of O(log(n)) for a less ELI5).


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

[User] ELI5: How does air get drawn into our lungs by the diaphragm when we inhale? What's physically pulling the air in our nose/mouth?

[Assistant]
The chest cavity is a cavity. It's a closed in area that experiences a change in pressure when the diaphragm pulls down.

This has a vacuum effect which pulls in air through the nose and down to the lungs.

When the diaphragm relaxes, the pressure in the chest cavity pushes the air back out.

So, when you inhale, the diaphragm and other muscles pull down which decreases the pressure in the chest cavity and draws air down through the available openings.


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

[User]
[Killer Klowns from Outer Space] Did the aliens take inspiration from Earth clowns, is it an ancient aliens thing inspiring mankind, or just a coincidence?

So, I think it's really a stretch to think it's a coincidence. But clowns have been around for a real long time.

Is it possible that the innate fear of clowns so many people have is some sort of genetic memory of these predators?

Is the clown form of this aliens just a disguise, or a glamour, like Pennywise?

[Assistant]
Nobody knows for sure which came first.

What IS clear is that its not a disguise, thats actually what they look like. Remember, most of their kills are some sort of clown based weaponry. They just come from a world where thats normal.

So its either that clowns just coincidentally look exactly like these killer aliens, or the Killer Klowns had come to Earth at some point in the past and clowns are based off of them.


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

[User] [Halo] Why didn't the Covenant drop ship just stick around and slay the humans with its powerful turret instead of continuously dropping off small infantry units to be slaughtered by the Chief?

[Assistant]
Arrogance.

If you read the books, they basically did that for most of the war against humanity, when Reach was conquered they felt they had humanity on the ropes as canonically, they could decimate earths fleets and biospheres while the Spartans are about as powerful as a single sanghelli (Biofoam, regenerating shields, good luck and just simply being that badass were John-117s saving graces).


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

[User] ELI5: What are the leading theories attempting to explain "Deja-vu"?

[Assistant]
The prevailing theory is that the sensory input is stored to memory as it is being "experienced" as a live event by the brain. But sometimes, signals get delayed, and the input gets put in memory a tiny fraction of a second before it gets experienced.

When your brain is processing what you see and hear as something happening "now", it is constantly searching your memory to see if this has happened before, because our brains are wired for pattern matching as a survival mechanism.

But if what you see and hear gets to memory before your brain starts to search for similar events, then the brain gets a trigger -- "Hey, this is in memory! This might be important!" And then, the brain starts to search through its memory for the details of when this happened before -- but by then, the timing issue has resolved itself, and it can't find anytime when this happened before, except of the memory of it happening just a moment ago.

So what you are left with is the sensation of recollection without any details of what you're recollecting -- and that's exactly what deja vu is.


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

[User] [Marvel/DC] How wealthy are various crime lord and criminals like The Kingpin, Bullseye, The Penguin, The Riddler, Two Face, etc?

[Assistant] Bullseye once claimed to be richer than Norman Osborn, *to his face* (and this was back when Osborn was in charge of HAMMER).  This is because he hardly ever spends the money he's paid for his hits, and only charges his exorbitant prices to ensure that he'll get *challenging* jobs.  He *has* murdered people for free, but only when he personally *wanted* to or it would be amusing to him.


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

[User] What are some good books on the Great Depression?

[Assistant] The Lords Of Finance- won a Pulitzer Prize.  It breaks down the economic history of the federal reserve and western economics starting from the 19th century on forward through the Great Depression.  By the time you get to the Great Depression in the book it all feels inevitable and that optimistic fervor that drove Americas roaring 20s was of a nation ignoring the realities of the world outside its borders after WW1.  The Treaty of Versailles was the most devastating agreements in the history of our world.  You will also learn about the real world secret wealth society that saved the US from complete collapse back in 1907 as well as the banking heroics of JP Morgan.  It also covers some of the interesting aspects of Hoover and his role.  How he was a beacon of warning in the mid 20s, but resulted in being the biggest representative of American poverty in the 20th century. A fantastic read that flows through the fingers in a few days.


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

[User]
Why is silver often used in topical antifungal and antimicrobial products?

I imagine it's a very small amount of silver, but I've never heard of silver being used in this way. What about the metal makes it so good at being antimicrobial or antifungal?

[Assistant] Silver has several ways it messes with cells, such as by puncturing the cell membranes when silver ions come into contact with them, or by binding to cell components that expect other ions/compounds and getting in the way of normal operation.


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

[User] ELI5: Why do large numbers before the decimal point get separated by commas in groups of 3, but numbers after the decimal do not?

[Assistant] Most of our numerical punctuation rules as used by the general public come from accounting, and in accounting there is no reason to use decimal points farther out than the 1/100th place but there is reason to use thousands and millions indicators.


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

[User]
ELI5: Why do referees in soccer games fall for the obviously fake injuries, and penalize the opposing team? Why hasn't anyone changed the rules in the game by now to prevent players from faking an injury to cheat the game?

I dont watch soccer at all, but it seems like players do it all the time. These penalties could be game changers.

[Assistant]
Actual Soccer/Football ref here:

The issue is: refs don't have replay, slowmo, or the best vantage point all the time, so you do you best to sort it out through your experience of reffing games.

It is already illegal to take a dive, but many times there is actual contact between players, just played up. In soccer, the flow of the game ("advantage") is taken into account when deciding what to call.

If the offense is making a break away towards the goal and an offensive player is tripped by a defensive player, but maintains control of the ball and keeps moving towards the goal, it would be, effectively, a penalty against the offense to stop play in order to have a kick (even though it is for the offense)

Refs are aware of players taking dives and we do think about it. Here is a secret: if a Ref makes a bad close-call on a penalty for one team, they will often consciously-or-otherwise try to balance it out for the other team if they are able.


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

[User] [The Elder Scrolls] If Argonians hatch from eggs, why do females have breasts?

[Assistant]
While Argonians are physically reptilian, their parental habits are mammalian. Which is to say that they raise their young.

"But they're lizards! It doesn't make sense that they would adopt a mammalian physical trait."

It doesn't make sense that people shoot fireballs from their hands. Fear not, there's an explanation. The Argonians are genetically modified lizards created by the Hist to serve them. The Hist added whatever traits to the Argonians they deemed useful.


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

[User]
ELI5:Why can't commercial airplanes deploy Parachutes for use in case of emergency landings where all other manoeuvres or options to save the plane have failed?

Something similar to ELS - Earth Landing System (used by Spacecrafts / Shuttles for re-entry into Earth's atmosphere), an automated system that reacts to barometric sensors and timers to deploy chutes before hitting the ocean for a safe landing!

[Assistant] Some smaller planes are equipped with this exact thing. The issue is any parachutes big enough for a commercial jet would take up too much space and weigh too much to be practical for a commercial aircraft. They are already designed with so many failsafes that it simply isnt worth the money. Plus you would probably need multiple parachutes given how fast a jetliner flies. If you just deployed a main chute youd probably rip it right off the plane.


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

[User] [All Star Superman] What exactly did Lex Luther see when he had Superman's powers that made him understand how the world works?

[Assistant]
Everything.

But for a real answer, he saw the connections of the universe. In general most creatures only comprehend a small percentage of the information we get from our senses. Most of the sounds, smells, etc are discarded to avoid overwhelming our minds.

Lex was likely able to process all of this information and even more of it thanks to his enhanced senses and intellect. This means being able to feel the vibration of the universe and how every thing and everyone is connected by the thread of space and time. He would be overwhelmingly aware of everything and everyone around him. It would be impossible for him to ignore their presence.

In short. What Lex saw was that we're all we've got. He was unable to disconnect himself from the rest of the world with the illusion that he was above or better than them.


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

[User]
ELI5: The process of animals receiving oxygen inside eggs, and how they transition to breathing once hatched.

How do animals receive oxygen inside eggs?  Then once hatched, how do they know to start breathing and or how does the process instantly change?

[Assistant]
I read about this at a dinosaur exhibit. When bird or reptile lays an egg, two membranes are formed below the egg shell. Imagine two layers between egg shell and the egg white. And between two layers is air sack which holds oxygen for the developing embryo. But this air sack needs to be replenished and the embryo must be able to release carbon dioxide. And here is where the amazing eggs shells come into play because they are made of tiny pores. A chicken egg is said to have about 7000 pores, approximately. As the chick grows, the pores on the egg shells allows oxygen and carbon dioxide to circulate to and from the air sack.
Once the chick is fully formed, it slowly positions it's beak under the inner layer and pierces through the inner layer to breath from air sack. And then it pierces through the shells and starts breathing oxygen from the atmosphere.


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

[User] ELI5: People are able to consume large amounts of beer, sometimes even a gallon or more in 1 sitting. But to drink a gallon of plain water is extremely difficult. Why is it easier to drink so much beer?

[Assistant] It's the time span that matters. You don't drink gallon of beer in 5 minutes. If you had to drink a gallon of water on the time span of whole evening (like you do with the beer) you would most likely do it. As others said beer is basically a flavoured water with a little bit of ethanol. If you can drink certain amount of beer you can definitely drink the same amount of water.


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

[User]
Does the human body recognize symbiotic microorganisms?

To my understanding, most of the cells in our bodies are not our own, but are rather outnumbered (ten to one by some estimates) by our microbiome, which led me to this question.

Does the body's immune system recognize (and therefore leave it alone) symbiotic microflora?  Or does such microflora just avoid the places it could be found by the immune system?

Or is it possible that symbiotic microflora just simply masquerades as our own cells?

If the body does recognize such microflora, how does it do that?  Is it simply something that we've evolved?  Is it something that the microflora have evolved?  Is it a little bit of both?

[Assistant]
Symbiotic microflora existing in the gut is tolerated by the immune system due to a couple of mechanisms.

Firstly non-harmful organisms don't do any harm to the body (eg. kill cells or invade) so the body doesn't produce the inflammatory mediators that cause immediate inflammation and when samples of the organism are presented t to the adaptive immune system they are present in a way that causes the generation of tolerance rather than an active immune response. This forms this set of cells called regulatory t-cells that go around killing off anything attacking the symbiotes and secreting anti-inflammatory mediators where ever they detect the symbiotes.

Secondly the way the immune system is set up in the gut is such that responses aren't readily generated to the content of the gut. The body constantly samples the contents of the gut, and but in the absence of damage or invasion it just generates tolerance.

Those ended up sounding very similar.. . Basically immune tolerance instead of activation is generated in response to gut flora simply due to the location of the pathogens, and that no damage is being detected.


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

[User] [WH40K] What is the Blessed GEOM's view on.... beer?

[Assistant]
Like any other invention of mankind, the brewing and moderate drinking of beer is to be celebrated and upheld by humanity. It is said even to this day that the Emperor has Russian Imperial Stouts aging next to the Golden Throne, ready for his consumption when he awakens.

However, pumpkin-spice beer is heretical and all consumers are ordered to report to their regimental commissar for summary punishment.


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

[User]
ELI5: when does the tip get charged from your debit/credit card at restaurants if they swipe it before you add tip?

At restaurants, they charge your debit/credit card before the tip is added. When does the tip get charged from your card?

[Assistant] The resturant staff will, at the end of the night or other low-volume time, enter in tips from reciepts into their computers.   As the credit card transaction has not been finalized yet, it still can be modified to include a tip.


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

[User]
What causes black holes to have an upper limit to their rotational speed?

Wikipedia mentions the theoretical upper limit to how fast a black hole can rotate. What is the limiting factor?

[Assistant]
The *intuitive* reason is that angular momentum has an associated rotational energy. This energy increases the mass of the black hole (through E = Mc^(2)).

Now, if you fix the total mass M, increasing the spin J then increases the fraction of M that is due to this rotational energy, and decreases the fraction of "normal", or "bare" mass (mass it would have if not rotating).

At a certain point, the bare mass becomes zero and M is entirely due to the rotation. This is an extremal Kerr hole. If you continue increasing J then the bare mass must become negative, which means the BH has become superextremal. Superextremal BHs are unstable and are impossible to create. Intuitively because negative mass is impossible.

Thus, for any given total mass, there is an upper bound on the spin which is given by the extremal black hole. Normal black holes satisfying the bound are called subextremal.


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

[User]
Solving world hunger with enzymes? Why not?

We have pills which give us enzymes, such as lactase, which allow us to digest certain sugars, such as lactose in dairy.  Why then is it that we cannot make a pill for cellulase, enabling people to digest the cellulose in plants and possible solving world hunger?  Does it have anything to do with the fact that it is never found naturally in the human body?

[Assistant]
Because world hunger is not a food problem.

It's a problem of delivery. Most of starving people and people who don't get enough nutrients, live in unreachable areas. Those areas can be unreachable due to natural caused (common in SE Asia, due to rainy season, etc.) or due to man-made problems (wars, other conflicts).

The reason scientists want to introduce Golden Rice in south east Asia countries (rice with Provitamin A) is because these areas are unreachable for most of the year, there is no where to keep food (it would be spoiled), etc. and not because we want to poison poor children with GM rice.


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

[User]
Whats the difference between industrial and competitive programming?

I know that in school (both high school and college), students are taught competitive/algorithmical programming. However, Ive heard that what we do in school is rather different from industrial or real programming.

I dont quite understand what this means. Whats industrial programming and why is it different? I suppose that real problems are much more complex, but is that all?

[Assistant]
In industry software development is done by adding small incremental improvements with a big focus on keeping the code: tidy, reusable and extendable so less time is spent re-inventing the wheel and fixing bugs.

However in competitive programming there is often a strict time limit and its unlikely that the final result will be used again. So most attempts to make tidy or reusable code go out the window and the only focus is making something that just works.

Think of it like building a lego helicopter vs buying a model. The lego helicopter will take time to build but you can add guns or swap out parts later, while a model can't be easily modified.


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

[User] ELI5: Whats the difference between a psychiatrist, psychologist, and a therapist?

[Assistant]
Psychiatrist: a doctor, who went through med school, who prescribes psychiatric meds. Occasionally also provides therapy.

Psychologist: person with doctorate level education (PhD) but not medical doctor. Can do a range of jobs: be a therapist, do psych testing, consult for many fields, etc. In USA- school psychologists just need Masters degree, but any other psychologist is PhD.

Therapist: person who delivers therapy, usually referring to talk therapy. Can have a range of qualifications, like: usually a masters degree (at minimum) may be LCSW/LICSW, LMHC, LMFT, psychologist, etc. Generally does not prescribe meds unless they are also a nurse practitioner or  psychiatrist. Note: there are other therapists, like occupational/speech/behavior but you usually hear the word in front of therapist in that case.


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

[User]
CMV: Log x should never be used to mean log base e of x/ln x

In calculus and higher math classes, there is an epidemic of professors and mathematicians that casually use log x when they really mean ln x. This behavior is not only nonintuitive, but is also confusing, to the detriment of student learning.

- from the moment students are taught about logarithms, they are taught that log x means log base 10 x. This implication is used in science, math, and calculator buttons. Its confusing when professors in higher math classes start using it to mean something else.

- there is ALREADY a notation for natural log x: its ln x. I get that natural logs are easier to work with in calculus, but its silly to redefine what log x means when ln x is already defined to mean this.

- ln x is not only already defined, but it is actually less work to write it. It takes one less chalk, key, or pencil stroke to write ln x than log x. So even from a pure time/efficiency point of view, its better to use ln x than log x.

In conclusion, there is no good reason besides convention to say log x when you mean ln x, no matter what level of math you are doing. For the benefit of students everywhere, this irrational behavior should be recognized for what it is stamped out.

Ok, my view has changed: I can see that mathematicians value log x as base e, whereas engineers argue for log x base 10. I dont believe using log x as ln x needs to be stamped out, but it might be worth looking at how we teach logarithms in the first place.

[Assistant]
> its silly to redefine what log x means when ln x is already defined to mean this.

You only think it is *re-defined* because of your personal learning arch.  Log has a long history of having a base of *e*.

If you want to specify base 10 unambiguously, you can either use log_10 or lg.

> Its confusing when professors in higher math classes start using it to mean something else.

Unfortunately sometimes notation is confusing, but the goal of notation isn't to make it simple for new learners, but rather for people in the field to communicate their ideas.  And in order to join that field, you must be trained in the notations that the people in the field use to not only understand current notation, but historical notation.  If they avoided teaching that log can sometimes mean base e in many fields, you'd have trouble understanding the published work from the past in that field.

Many fields have a standard that log means base e, and if it isn't clear it becomes clear the first time someone uses log in a paper.  I've never seen someone jump back and forth between the two without doing something to more explicitly establish what base it is.


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

[User]
When we say a chemical is odorless, do we mean that it is odorless to humans, or that it is truly odorless?

Is there even a way to know?

[Assistant]
When we talk about odorless we are saying that the human nose is unable to detect it.

Typically compounds that have an odor have a small amount of vapors which come off the compound. When these compounds enter your nasal cavity it interacts with the sensors there giving you the sense of smell; however, your nose is only calibrated to sense certain molecular configurations.   Anything which does not bind to your sensors is odorless and thus your body can't detect it.

But different animals have the ability to smell things we do not (Dogs in particular have a great sense of smell) and also we can create machines which detect molecules our noses can't.


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

[User] ELI5: the scope of a gun is on top of the nozzle the bullet comes out of, so wouldnt the bullet hit a bit lower than where you aimed for?

[Assistant] The scope is adjusted to correct for this (and for bullet drop in flight) at a specific distance. If you change distances, you need to readjust the scope. The scope is not purely parallel to the barrel, otherwise the bullet would always hit low.


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

[User] ELI5 When a food is considered to be "processed," what does that actually mean?

[Assistant]
Basically, every food you eat is processed, unless you grow and pick/slaughter it yourself.  These days, when people use the word "processed", they mean more along the lines of added preservatives, fillers, etc.

For example, if you go to the deli in the grocery store and want some turkey, all the turkey is going to be processed, since the animal has been killed, feathers plucked, meat taken off bone, then reassembled into the piece that is sliced.  Oftentimes, other things such as preservatives will be added to help with shelf life, flavors, etc.  "Fillers" are also used to help a small amount of meat become a larger piece to slice.

That's not to say that all turkey lunch meat would be like that.  There are some that have nothing added to it, other than the meat off the breast of the turkey.  These, however, are still considered processed.

TL;DR: all food you purchase from the grocery store is processed.  Unless you grow/slaughter and cut the meat off the animal yourself, it is considered processed.  But when people say a food is "processed", they more often than not referring to various preservatives, fillers, etc. that are added to the food that aren't naturally a part of the plant/animal.


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

[User] [Harry Potter] Why didnt Dumbledore make the entrance to the Third Floor Corridor immune to Alohomora?

[Assistant]
It wasn't only a means of protecting the Philosopher's Stone, it was a deliberate *trap*. The idea is that anyone who would want to steal the Stone would be able to get through most, if not all of the traps bar the Mirror.

Dumbledore knew Voldemort was after it and designed it to play to his ego.


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

[User]
ELI5: what is fat in the human body? Is it in a cell?

When you lose weight do the cells die? If the cells dont die, how long does it take? Minutes, days, weeks? Nothing seems to discuss how fat is stored in the human body except to say that it is....  Thanks!

[Assistant]
The fat is stored in specialized cells named "fat cells". They absorb the fatty acids that are hanging about in your blood and prepare them for long-term storage within themselves.

When you need the fat they convert the fat in to something the body can use, like the fatty acids and sugars, and release them in to the bloodstream to be used by the rest of the body.

The cells don't die, they simply get smaller as they store less fat. You can think of fat cells as unusually complicated containers of fat. When you're eating, they get bigger. When you stop eating, they get smaller.


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

[User] ELI5 : Why are space missions to moons of distant planets planned as flybys and not with rovers that could land on the surface of the moon and conduct better experiments ?

[Assistant] A flyby only requires acceleration to escape velocity from earth, then some more to send the craft on its way.  A lander or orbiter also requires massive fuel with the spacecraft to slow it down again as it approaches the target, and to match orbits with the target. It's not technically that much harder, it's just that the fuel weighs so much, and reduces experiments, sensors, and whatnot that they could take with them.


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

[User]
CMV: I think once you become a "grown-up" and have family, you become depressed.

My mom and dad don't really live what would be considered a "happy" life. My dad has anger issues, hates his job (got laid off 7+ times) and is constantly stressed out. My mom told me today, "I think people tend not to like me...". She seems to have self-esteem issues which is ridiculous because she is the sweetest, caring and most loving person I know.

Also, it seems like once you're used to your job, and family (grown-up), you lose all your friends. I haven't heard of my dad talking to a single friend ever since I was a toddler, and the only friends he talks to now are at church. And even then, they never hang out outside of church. Growing up into the church, I've been constantly surrounded by the same families with the same cookie-cutter parents. This reinforced the notion that parents just get used to life and go through that stagnant cycle of work, bills, church, etc. I also understand that with age, connections grow thin and the only the best friendships survive because of the dedication required to keeping in touch.

I know that my view isn't correct, and many families out there are happy, but I really need to hear it for confirmation.

Edit: I've found the answers- thank you all for the valuable insight. Reddit delivers.

[Assistant]
The fundamental things that makes people happy and keeps people going are goals.  Your life should always be building towards something- whether it's getting a new computer, tending a garden, beating that video game, having and raising kids- people necessarily hate stagnation.  You hear it all the time- "Honey, we're in a rut."

Now, stagnation is certainly a pitfall of adulthood, but it isn't an inevitability.  And it's a subtle difference, so the confusion is easy.


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

[User]
[DC] How does Clark feel about the Flash throwing charity races?

How did Superman feel when he found out Flash was throwing the charity races they had?  Was he ok with it as it was just a spectacle to raise money or was his insulted that the flash let him win like a first date playing air hockey or a kid playing monopoly?  Is Superman's morality ok with rigging a race if its to raise money to save Koalas?

[Assistant]
Superman's reaction is essentially the same as Thor when Captain America lifted his hammer - "I KNEW it!"  Superman and the Flash are good friends, but Superman always suspected Flash was faster.  Both Superman and the Flash consider charity races to be fun events, where really their egos don't matter as much as helping the kids/koalas/hospital or whatever they're helping.

> Is Superman's morality ok with rigging a race if its to raise money to save Koalas?

Yes.  Same reason Superman's morality is ok letting a kid beat him in arm wrestling at a charity event.  Superman doesn't have a hard set moral code like Batman.  Superman has described his moral code in its entirety, "There is good in this universe and there is bad, and it isn't hard to tell which is which."  Superman considers things like little white lies that benefit charity and give the people a show to be acceptable.


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

[User]
How pancreas cells feels level of glucose?

How pancreas cells feels level of glucose in blood,  for producing insulin or glucagon?

[Assistant] -cells have the facilitative glucose transporter GLUT2 on the surface of their membrane, these make the cell take up glucose from circulation which through glycolysis raises the atp/adp ratio. In response to this change potassium channels open which activate downstream signalling to produce insulin.


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

[User]
[Tomb raider] Did anyone train Lara Croft?

Alot of her skills seen like they could have been picked up legally; but she's still a great shot; where'd she learn how to do that? Guns are persona non grata in the UK.

[Assistant]
Shooting for sport is still legal. Target shooting of both pistols and rifles, as well as game shooting with shotguns and rifles. The licensing of handguns is really strict now, since Dunblane, but it didn't used to be particularly so.

It's niche and expensive, but she's aristocratic so exactly the sort of person to shoot.


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

[User]
ELI5: How do online games with many players in the same area ensure everyone sees the same things at the same time?

Title. I think I'm talking about latency/syncing but I'm not too sure.

[Assistant]
Short answer: they don't.

More in depth answer: the players(also know as clients) are constantly sending their actions(movement, attacks, etc) to the server(host) which processes the inputs and then sends updates back to the clients.

Normally this happens so fast that the human brain doesn't notice any inconsistencies(a "good" server response time is 0.01 to 0.1 seconds) but when there are delays in processing or connection(sometimes called lag) the host will process commands as they were received which can cause characters to "rubberband" or teleport around.

In a fast paced game(like an FPS) this is very noticeable, but in slower games the programmers will often just smooth over any rubber banding(after all, if you're chilling in town in an MMO does it *really* matter whether that player is *actually* standing there or walking away?)


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

[User] ELI5: Why haven't we developed energy applications based on fusion, yet we can make weapons that use fusion quite effectively (i.e. hydrogen bombs)?

[Assistant]
Thermonuclear (fusion) weapons create a very fast and violent reaction that puts out a huge amount of energy very quickly, but are over the second after they begin. The fusion portion of the weapon actually needs a fission bomb to get it started.

Fusion reactors on the other hand, need a slow stable reaction that keeps going. Research is constantly being done, but there are some challenges:

1) Starting the reaction - detonating an atomic warhead in your reactor is a poor way to kickstart your reactor. Better methods are in the works.

2) Maintaining the reaction - as the fusion reaction goes on, the fuel wants to separate, ending the reaction. A method is needed to keep the hydrogen isotopes packed together.

3) Containing and using the reaction - most materials do not hold up well to the extreme heat generated by the reaction. A method to contain the reaction while drawing heat from it is necessary, without having to constantly turn the reactor off for maintenance.


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

[User] ELI5: Why Do I Feel Like Throwing Up After Running Or Working Out Too Hard?

[Assistant]
When you train, blood is withdrawn from your digestive organs and reassigned to the muscles. If you train too hard, the digestive organs lack sufficient blood and energy supply and are struggling to do their work properly.

Given you still have food to be digested, your body is preparing to get rid of it in order to free up more resources, currently needed to digest.


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

[User] [LoTR] I remember seeing something somewhere about how Gandalf has to withhold and restrain his power, being more for guidance than direct action. Just how powerful is he and how much could he influence things if he weren't stymied like that (if it's even true)?

[Assistant]
Gandalf and other Istari are held back by their frail forms of old men. If Gandalf wanted he could unleash his full power and be more akin to a Balrog.

The issue is if he dies he loses it all. When Sauron died all his power was in the ring so he basically couldn't conjure up more than a frail spirit that was left wandering invisible and alone. The same can be said for Saruman, Balrogs, even Morgoth himself.


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

[User]
[Mass Effect] Why do the Reapers bother with a ground offensive?

So we are studying The Reaper War in school, and going over all the major battles. As our professor started talking about The Reaper ground troops and strategies, I started to wonder why a species of dreadnought class ships would need to bother with sending out soldiers when they could just bombard us to extinction.

[Assistant] The point of the Reapers wasn't to make everyone extinct. Some stuff has recently become declassified that suggested they were attempting to harvest the species for some sort of experimentation they called a "resurrection." Whatever that means, the point is that they needed to gather people to do it. There's an often overlooked prelude to the Reaper War that has a lot of rumors, regarding the Collectors, who were apparently invading and abducting human colonies near their space. There were some connections between the Collectors and the Reapers, though the exact relationship remains unclear. But who knows, could've just been a chain of bad reactor accidents or something that got the modern equivalent of a ghost story made up for them.


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

[User]
ELI5: Why are guitar, bass and drum kit the basic instrumental core of modern music?

Of all instruments (and of course a few of them are used very often - such as keyboards or sax, among others - though not as much as the "essential" ones in the title), why exactly is the vast majority of modern music genres based on those three instruments? Even the drum kit itself, why is it the way it is, with all the diversification of drums and percussion in the world? Is there a special reason for this quintessential instrumental selection? What made that happen, what explains its lasting establishment above all others and could they even become obsolete to music in the future?

[Assistant]
They're the simplest method of providing a chord sequence, a harmonic backup, and a rhythm, all while being easy to learn, store, transport, and amplify.

The guitar and piano are the most common instruments capable of playing full chords - other lead instruments (think saxophone, trumpet, violin, etc) are only able to play a single note, requiring other band members to back them up to flesh out chords.  Of the two, guitar and piano, guitar is a bit easier to learn and to play simple chord structures, and it's much, much easier to travel with and set up.

The bass is popular for the exact same reasons as the guitar, except instead of a chord structure, it gives you a harmony, countermelody, and bass support.

The drumset is simply the most convenient way for one person to provide any percussion needed to keep a rhythm in various styles.  They're completely modular, meaning you can modify them with anything - tambourines, gongs, xylophones, whatever.


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

[User]
[Dragon Ball Z] I heard that the supreme protector of Earth, Son Goku got shot by a gun by one of Freiza's soldiers... where can I get one of those guns and how common are they?

It seems like better home protection when you can incapacitate Gods with a well timed shot.

[Assistant]
There was a scene in the cell saga (it may or may not have been filler, but it illustrates the idea well enough) where Krillin throws a rock at Goku's head while he sleeps.  His idea is that Goku, being in his Super Saiyan form, would just instantly blow the rock into a million pieces or it would just bounce off of him or something.  But because Goku wasn't channeling any energy into defending himself, when Krillin threw the rock, it just hit him on the head and hurt like hell.

It's the same principle with the gun.


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

[User]
ELI5 : 0K (Kelvin) is supposed to be the lowest temperature reachable but it's only theoretical. In definition it means there is absolute zero motion. But why is that, that some elements are still not "solid" in this temperature?

Like helium which never turns into a solid block on normal pressure?

[Assistant]
The protons and neutrons in atoms are made up of particles called quarks.  Quarks have a very low mass and what is ultimately giving a proton/neutron most of its mass is that fact that the quarks inside of them are spinning at close to the speed of light.

There are three quarks in a proton.  Two of those quarks have a charge of +2/3.  One of them has a charge of -1/3.  The quarks themselves are arranged in a sort of triangular shape.  At large distances these charges cancel out so that a proton appears to have a net charge of about 1, and for nearly all applications we can consider that charge to be 1.  But its not *exactly* 1 - it varies depending on the position of the quarks relative to you.

When the negatively charged quark is on the opposite side of the proton you experience a charge that is very, very slightly stronger than 1.  When it is on the side of the proton facing you, the charge is very, very slightly less than 1.

Neutrons work the same way, except the one of the quarks in a neutron has a charge of 2/3 while the other two have charges of -1/3.  So depending on the position of the quarks in a neutron, you will experience a charge either slightly higher or lower than 0.

This extremely slight net charge is sufficient for a proton or neutron with "0" energy to, nonetheless, cause other nearby protons and neutrons to wobble a bit, resulting in them having some very minimal amount of energy.  This, in turn, causes atoms to have a constant, slight wobble (which will also result in the wobbling atoms very slightly "bumping" into nearby atoms).

We can't stop this wobble because on a very fundamental level we don't have any mechanism to influence the quarks inside of proton/neutron, so we can't slow them down.  Also, because the speed of the quarks is, itself, responsible for most of the mass of the proton/neutron, if you did somehow manage to slow those quarks down they would stop being a proton/neutron and start being something else, which doesn't necessarily solve the problem if what they turn into can't be measured, like dark matter - or if the energy in the quarks ends up getting liberated, such as through the transformation of a quark into high energy electrons or positrons.


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

[User]
What type of Math is used in Computer Science?

Can someone tell me if the math in Computer Science is hard? Im currently learning Calculus 1 and 2 in school and I feel like Im understanding them very well. I read online that calculus 1,2,3 and 4 are used in computer science and that, in general, the math is hard. Can someone tell me what to expect if I decide to major in Computer Science?

[Assistant]
In theoretical CS, mostly discrete math. it is easier than calculus. mainly: graph theory, combinatorics, number theory (in cryptography), and mathematical logic. but you would be doing a lot of mathematical proofs in other areas not typically considered math like formal languages, automata theory, analysis of algorithms, complexity theory etc.

In artificial intelligence and machine learning you would need statistics, probability and calculus.


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

[User] Since light takes time to travel how many stars in our night sky don't actually exist anymore?

[Assistant] The stars you can see in the night sky are all pretty close -- tens or hundreds or, in a few cases, thousands of light years.  Stars have lifetimes of millions to billions of years.  So probably they all still exist.


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

[User] CMV: Assad and secular nationalists are the best force the middle east has, and supporting any other faction is irresponsible and will be the death of us all.

[Assistant]
Assad is not some secular paragon helping stem the tides of Islamism.  He funds Hezbullah and assassinated the relatively secular President of Lebanon (Hariri).

There is no "secular faction".  There are numerous religious and secular factions at war with one another, in complicated alliances.  If you are looking for a great secular leader, look past the tyrant Assad.


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

[User] [Infinity War] why did Thanos throw chunks of the moon at the heroes instead of use the power stone to melt them or the reality stone to turn them to bricks?

[Assistant]
It was his first day. Im shocked he figured out the time stone in less than a minute.

Come to think of it, he got the one from nova a week before, but the other 5 in less than a day, and the last three in less than 20 minutes.


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

[User]
[Lord of the Rings] Does the One Ring enhance your strength?

I was thinking, since it gave Gollum an unnaturally long lifespan, did it also increase his strength? If he stronger off with the Ring than he was as Smeagol? And if so, does that apply to anyone who wields the ring?

[Assistant]
Quit the opposite- Gollum is described as both literally and metaphorically a frail shadow of his previous self.

Remember, there's a big difference between something that gives you eternal life and something that simply stops you dying.


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

[User] When you see a shockwave what are you actually seeing?

[Assistant] Air at different densities refracts light differently, like when heat waves coming off the pavement or a grill create pockets of air at different densities.   The shockwave has different densities of air ahead of and behind the shockwave, which gives a lensing effect.


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

[User]
CMV: Two States Policy is Dead for Israel and Hamas

Majority of the Palestinians want to get the entire former land of Palestine back to the Palestinians, and get all their refugees back.

Majority of the Palestinians also reject the "Two State" solution.

They want the "one" state of Palestine re-instated.

What will happen to the 7 million Jews who are now in Israel is not clear under this demand.

Majority of the Israeli Jews , on the other hand, support annexing the entire land of former Palestine under Israeli rule, as a Jewish state.

Most Israelies now oppose the Two State Solution also, fully knowing that whatever little land they are leaving behind for Palestinians  is not at all viable for building a state.

What happens to the 7 million Palestinians inside such  a Jewish state, without democratic rights or equal protection of law is an inconvenient question that the Israelies are OK leaving unaswered for now.

As you can see, both the majorities from two sides are ignoring reality. 72 years is a long time and whatever happened during these seven decades, rightly or wrongly, are now reality, and they are here to stay.

Seven decades of reality has consequences.

Neither of these two parties can simply ignore what happens to the other 7 million people for the long run, even when one feels that they are the victim of the other.

Ultimately the 7 + 7 million Jews and Palestinians will have to live side by side , as equal citizens  of either just One or Two states, with equal rights.

It is most likely going to be just One state , where the Palestinians may not be able to live alone, but they will be the demographic majority.

Palestinians, therefore, have a lot to gain by asking for such a One State Solution with democracy, where they get equal rights as equal citizens , as the majority.

International Community should now focus on a one-state solution, more like China and Hong Kong.

[Assistant]
>It is most likely going to be just One state , where the Palestinians may not be able to live alone, but they will be the demographic majority.

Why would the Israelis ever agree to this? This seems like the worst possible outcome for them.


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

[User] How much energy would you need to create different types of mass, such as sub atomic particles, or even whole atoms?

[Assistant] In general you need energy equivalent to the amount of mass you want to create, according to Einstein's mass-energy equivalence. In practice, if you want to be able to generate any sort of particle out of nothing, you'll need much more energy to control the processes and machinery you use.


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

[User]
Why have CPU clock speeds stopped going up?

You'd think 5+GHz CPUs would be everywhere by now.

[Assistant]
tl;dr increasing CPU frequency is kind of like increasing RPMs on a car engine - it's one unit of how much power a car's engine is producing, but it's not so good for comparing multiple types of cars in terms of how fast they can go or how much they can tow.  If one person is driving a Toyota Corolla at 2000 RPM and another is driving a Ford F150 at 2000 RPM, that tells you very little about which is carrying more weight (IPC\*) or going faster (CPU benchmarks) or has more room (cache?\*).

You can push a car's RPMs higher to go faster, but then you produce **more heat** and it's harder on the engine; generally, there'll be a range of RPMs where it's most efficient and is designed to run stably - *frequencies are largely the same sort of thing.*

You can think of CPUs as having basically five metrics that improve performance:

1. Manufacturing tech - how small can pieces of the CPU be built?
2. CPU Frequency - number of times the core clock 'ticks' per second.  3, 4 GHz, etc.
3. CPU Instructions Per Clock (IPC\*) - number of instructions the CPU can execute during a core clock cycle
4. CPU memory\* cache/cache speed - amount and speed of memory that the CPU can use to store instructions/results
5. Design/layout of the chip itself

The implication being:

1. Make the manufacturing tech smaller and everything else constant = lower power requirements, less heat, faster on/off switching of transistors
2. Make the CPU frequency faster = more power requirements, less stability
3. Make the IPC higher = faster (more work done) at the same CPU frequency
4. More memory/faster memory speed = real-world improvements irrespective of CPU frequency
5. Design/layout = real-world improvements in cost, etc

A 4 GHz CPU in 2019 is actually much faster than a 4 GHz CPU in 2009, because the IPC (roughly the amount of work that gets done per Hz) is higher.  The 2019 CPU would also use much less power per calculation than the 2009 CPU, because the manufacturing tech is much smaller.  And it would feel faster because more of the work can be loaded into very fast memory very close to the actual CPU cores (instead of running back-and-forth to RAM).

Basically, they discovered about 10 years ago that they were hitting diminishing returns on increasing CPU core  clock speed.  So they looked to other areas where they could improve efficiency and/or speed: more cores, better cores (higher IPC), more on-chip memory, smaller tech = less power draw, etc.

For a real example: In 2008, a Pentium 4 at 2.8GHz had a per-thread PassMark score of 633; in 2017, an i9-7960X at 2.8 GHz had a per-thread passMark score of 2337.  Same frequency, drastically different amount of work getting done.