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

[User]
[Star Wars] How much free will do Jedi and force sensitive people have?

Does the force make it so that every major event is set in stone? Was there ever any possibility of Anakin not falling to the dark side or does the force demand that all of that stuff happens?

Do people in the Star Wars universe have any choice at all or does the existence of the force mean that everything that happens is pre-determined by it?

[Assistant]
Think of this way - the Sith *will* be destroyed. Balance *will* be brought to the Force. These are the endings, so-to-speak. No matter what path we walk down, they all make their way back to that conclusion.

Every event is not set in stone as if there was only ever one way for things to work out. Could Anakin have stayed in the Light and shunned the Dark? Of course he *could* have, but he didn't. He fell to the Dark Side, and brought pain and suffering to a great many people. Had Anakin stayed in the light, much pain would have been avoided, and it stands to reason that it *could* have worked out... but that's not what happened. Not because of destiny, but because of choice. It gave way to difficult times, yet Yoda and Obi-Wan both continued to trust in the Force - despite their inability to see how it would end.

To that end, they even made bad assumptions along the way. Obi-Wan believed ending Vader was the only hope for the galaxy. Yoda believed Luke should not have been trained in the ways of the Jedi. Both believed Anakin was dead (for all intents and purposes), and that Vader was irredeemable.

Yet, despite all that, the Force did not will Vader to die, it lent Luke the strength to fight the Empire, and it was there to accept *Anakin* back to the Light once he had destroyed the last remaining Sith.

As the saying goes, "All is as the Force wills it to be." That doesn't mean that everything is set in stone - it means that eventually, when the Force demands something to happen... it will find a way to make it happen. No matter what.


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

[User]
[MCU] A future version of myself just "borrowed" my Soul Stone sacrifice for 50 years. Is this still going to work?

Okay, so I was standing on the cliff on Vormir, about to toss my beloved wife off the edge, when a disheveled, distraught-looking version of myself appeared in a flash of light. He choked out something about "borrowing her for a bit", and the two of them vanished before I could react.

About 20 seconds passed, and my wife reappeared. Except this time, she looked about 50 years older, and she was alone. She tells me she led a full life and raised three kids with my doppelgnger, who recently died of pancreatic cancer.

Now, the thing is, she's still the same person, I still love her, and it's still going to tear me apart to sacrifice her. But I can't shake the feeling that future!me is trying to have his cake and eat it too. Is this going to trigger some sort of anti-cheat protocol built into the Stone, or does it only care about the love I still feel?

[Assistant] "Future you" isn't you, it's an asshole from another timeline; he didn't have his cake and eat it too, he ate your cake. Shoving your now old wife off the cliff still counts, and if you choose to use a time machine to go back and steal some other you's wife after the fact, that's their problem.


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

[User] [Harry Potter] Is going to a magical school like Hogwarts mandatory for non-muggles? Are there any homeschooled or self-taught witches or wizards?

[Assistant]
Yes, in the UK at least. Lupin explains in the last book that attending Hogwarts isn't mandatory (well, except for that one year when Voldemort was in charge) and that guardians are allowed to homeschool their children if they so desire. However, this is extremely uncommon and few do it.

Guardians are also allowed to send their children abroad to other magical schools.


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

[User] ELI5:How does our body generate heat during fever?

[Assistant]
The exact same way it always generates heat, through something called metabolism where sugars and fats are "burned" in chemical reactions to create energy.

The difference is that when the body is sick with some medical conditions such as the flu or an infection, it is programmed to raise the level of metabolic activity to scoot your temperature up. It does this because many forms of infection and disease don't reproduce as well at warmer temperatures. But it doesn't work all the time and in runaway fevers can raise the body temperature so high that organ failure or brain damage can occur.


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

[User]
I believe that space exploration is an unjustifiable waste of resources that owes its support to childish science fiction fantasies.  CMV

The reddit hivemind loves space, and NASA, and giving NASA money.  I strongly disagree.  It doesn't seem to me like space exploration or travel is remotely realistic or practical or that there is anything out there that can justify the cost.  R+D is great, and insofar as NASA promotes it that is a fine thing, but can't we achieve that same thing more efficiently by changing NASA into a dedicated R+D program and cutting out these space projects that seem to exist only as PR?

Our own solar system is so large that it seems impossible to get outside it without altering human biology in fundamental ways and I'm not aware of anything inside of our solar system valuable enough to be worth getting people or machines to.  Asteroid mining seems a laughable idea, since mining is an engineering problem and won't it *always* be easier to solve that engineering problem in earth's most inaccessible locations than in outer space.

Some people have a sentimental attachment to space programs, but I don't see that this should matter, since there are many things groups of people have sentiments about that we recognize as bad policy choices.    Is it simply the case that nerds are willing to apply a different criteria when considering things they like (NASA) compared to things they don't like such as farm subsidies?

[Assistant]
> Asteroid mining seems a laughable idea, since mining is an engineering problem and won't it always be easier to solve that engineering problem in earth's most inaccessible locations than in outer space.

No, it won't, actually. Getting something into space takes a lot of energy, but once it's there, many engineering problems become massively simplified. There's no air resistance, no corrosion, and no gravity. The amount of resources present in space makes the investment well worth it.

In addition to that, considering that we now have the ability to essentially make the Earth uninhabitable, it seems like a good idea not to put all of our eggs in once basket.


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

[User] [Thor/Thor Ragnorak] If Thor had had his "powers come from within" epiphany while in exile on Earth, could he have shot lightning without reclaiming his hammer?

[Assistant] I don't think so. At that point Odin very explicitly robbed Thor of his power, so the realization probably wouldn't have worked. Once he learned humility however, it seems that the Worthiness Enchantment relaxed a notch about that.


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

[User]
ELI5:What triggers evolution in a species?

I recently learned about cat's not drinking water near their food because of natural instincts they had developed.

This means that at some point, felines drank water and had to have died right? So how was that instinct developed/passed on if it involved something that would kill the host?

[Assistant]
There is no real trigger... Evolution is the survival of the individual who is best adapted to surroundings. Let's say a pack of mammoths ends up in the desert. Then the amount of hair determines how well a mammoth regulates its body temperature. The overheating mammoth dies, giving the rest of the mammoths more chance to procreate and pass their amount of hair to the next generation. Basically we always evolve, but random mutations that give an individual benefits or not appear randomly, so there's no guarantee that there will be change.

You could say that change of surroundings triggers evolution to cause change but evolution itself is always there.


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

[User] ELI5: How does a human being stay in a coma for many (like 10 or 20) years, and what wakes them up?

[Assistant] While you are in a coma, assuming that you are being kept alive and your brain has some function, your brain devotes a grear amount of enery to repairing itself. This process is difficult and energy intensive so some times it takes many years for the brain to repair itself to a level were you can remain conscious.


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

[User]
Do you burn more calories when you're sick?

When you're sick you can experience symptoms like increased mucous production and fever.  I imagine that since the body has to deal with these problems it would have to spend more energy.  Anybody able to expand on this idea?

Side question: when you have a cold, where the hell does all of that mucous come from?  It's non-stop!

**Edit:**  Thanks for all the info guys.  This subreddit is awesome!

[Assistant]
Yes, baseline energy usage increases ~15% with each degree increase in temperature.

Inflammation dumps a lot of chemicals into your blood that fire up the breakdown of fat and glycogen stores. Basically you mobilize your body's stored energy so that it can be used to fight infection.

Side question: Your respiratory tract from the nose on down is filled with "goblet cells" that create mucous secretions. These secretions trap infectious particles, which are then carried out of the respiratory tract by a "mucociliary escalator" -- basically, the other cells in your lungs have little fingers on them that push the mucus out of your body...onto your handkerchief.

The fluid for mucous production comes from your blood. Goblet cells synthesize a substance called mucin, mix it with water from blood, and pump it into your respiratory tract.


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

[User]
Why don't people bleed out during surgery?  When people get stabbed they bleed out.

The title is pretty self explanatory.  Surgeons cut pretty deeply.  It's my understanding that people feel pain when they get cut because it is the body signalling something is wrong.  So we give anesthesia to stop the patient feeling the pain.  But they are still bleeding!  For example, open heart surgery.  Do they just close the patient up before anything too bad can happen?  Or do they constantly recycle the lost blood through the patient's body artificially?

Thank you, knights of AskScience!

[Assistant]
As you can see from the comments, there are lots of reasons that patients don't bleed out.  A non-comprehensive list:

* Surgeons avoid severing major veins/arteries whenever possible, and use hemostats to control bleeding.

* Minimally-invasive surgical techniques can reduce bleeding significantly.

* The patient's blood may be captured and recycled.

* Blood may be transfused.


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

[User] ELI5:why are most European flags three stripes of color?

[Assistant]
The tricolor pattern was born as a symbol of liberty and revolution in Europe, in the 16th century, and then gained traction in the time of the French revolution and only increased in popularity to 1848, the "Spring of Nations".

The tricolor pattern was seen as the herald of a new age, an age where the feudal lords would finally be removed, and power was instead given to the common people. Of course, such transitions were often bloody.


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

[User]
[DC] Why is Superman so beloved by everyone?

Question from a long time ago but I just remembered it

basically there's this scene in doomsday clock where superheros are banned from operating outside of there home country..Expect Superman

he's so popular that even Vladimir putin hands him a podium when he shows up at an event and praises him while doing so

why? I know he's to the average DC human being the most powerful justice leaguer and  a decent person but what makes him different from every other superhero in terms of popularity?

[Assistant]
Superman's greatest power isn't his strength.  It isn't flight, it isn't heat vision, it isn't whatever the hell happened in the 50s and 60s.  Superman's greatest power - the one that keeps a character created in 1938 relevant to this very day - is his ability to inspire hope.  Superman is the embodiment of the idea that if you just hang on a little bit longer, dig just a little bit deeper, you'll be okay.

And the need to be okay isn't bound by country or planet or even space sector; it's universal.


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

[User]
I believe that, in the absence of a deity, there is no basis for human rights or morality. CMV.

I know that there are many people who don't believe in God, but believe in human rights. I would like to understand how and why. As a Christian, my belief in human rights comes from my belief that such rights are granted by God. In the absence of a God who decides what our rights are, I don't see a reason why such rights must exist. Here's my reasoning:

1. If there is no deity (or something outside of humanity which determines human rights and moral behavior), then there is no basis to make any sort of moral claim besides human reason and observation.
2. If we can only base our morality on human reason and observation, then morality (and human rights) cannot be objective, as there is disagreement among peoples. Furthermore, even if we all agree, it does not follow that any conclusion we may come to is correct.
3. Therefore, there is no basis for human rights or morality in the absence of a deity.
Going back to point 1. If you can give me something besides a deity which is outside of humanity which could decide what our rights are, then that would satisfy me, but I don't think that irreligious people have anything like that.

My main motivation for asking is that atheists typically believe in some sort of morality and certainly believe in human rights, but I can't tell if they believe in these things because to reject them is troubling or because they can actually articulate reasons why they exist.

Edit: People have been comparing moral truth to other kinds of truth, such as scientific truth. The problem with this comparison is that we assume scientific truth to exist independently of human reason and observation. For moral truth to be the same way, there must be an objective Good which is also independent of human reason and observation. My problem is that without a God I see no reason why this Good would exist.

Edit 2: To everyone bringing up Euthyphro's dilemma, I would say that it is a false dilemma. I can't speak for other theistic religions, but Christians hold that morality is a direct extension of God's nature. Suppose each being determines what is moral for himself. Humans are mutable and imperfect, and thus our morality will be mutable and imperfect. God is immutable, perfect, and the only necessary being, thus his morality will be immutable, perfect, and objective. Moral good is then an extension of who God is.

[Assistant]
Take a schoolyard. If there is one kid who hits another kid, children will recognize that as a mean thing to do.

They don't need a parent or adult to tell them that it is wrong. The bully might need an adult to tell them, but the victim and the other children don't.

Morality is created by men. We don't need a god to tell us to follow the Golden Rule. Every single culture and society that has ever existed has figured that one out. This is the basis of morality.

The definition as written on Wikipedia is:

>Morality (from the Latin moralitas "manner, character, proper behavior") is the differentiation of intentions, decisions, and actions between those that are "good" (or right) and those that are "bad"

The definition in Webster's dictionary is:

> beliefs about what is right behavior and what is wrong behavior : the degree to which something is right and good : the moral goodness or badness of something

Neither of these definitions say that morality needs to be universally agreed upon. Morality doesn't have to be objective. Each person can have their own moral code. Subjective morality is morality nonetheless.


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

[User] [Star Trek] What inhabited planets exist in the various Neutral Zones? Since fleet ships can't enter the Zones typically, who do they trade with? Who defends them?

[Assistant]
Warships cannot enter into neutral zones without violating treaty, but merchant ships can. These civilian trading vessels can go anywhere they please, albeit with some possible risk as civilian trading vessels are unarmed and thus helpless against a warship.

The civilian merchant freighter, Kobayashi Maru, is perhaps the most famous example of this. It can enter any neutral zone it likes without violating treaty because it is an unarmed civilian merchant freighter. The downside to this is that it relies entirely on the goodwill of warships to not fire upon it, and to protect it should it need assistance.

Any Starfleet vessel is still a warship. Yes, their primarily mission is not war, but they still carry massive amounts of armaments and shielding. Even a Starfleet science vessel is still extremely heavily armed. They are warships in all but name.

Colonies will typically build their own militia or planetary defense forces. The larger and most established the colony, the more elaborate their militia will be. A planetary militia commonly uses sub-light ships. This makes ships cheaper and easier to construct and because these ships do not need to travel to other planets, there is no need for FTL.

Bajor is an example of an independent planet with its own militia. A planetary militia is of course completely outmatched when it comes to that of any star system spanning empire, but such a planet isn't helpless. Not entirely, at least.


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

[User] Is it possible for an earth-like planet to be the size of our sun?

[Assistant] The earth is about 4 times denser than the sun. If you scaled it up to the size of the sun, you'd have a sun-sized ball of iron and other elements. The force of gravity would likely collapse the ball. It depends a little bit on the exact composition, and what you consider to be the boundaries of the sun.


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

[User]
How do forest fires start?

Edit: how does lightening start forest fires?

[Assistant]
A bolt of lightning can have a temperature of 5 times that of the sun (50k F vs 10k F). That is hot enough to ignite many (most) substances, especially in situations where the fuel is readily available, in the right conditions (super dry) and collected together (like dead brush.)

You can start a fire with a tiny electric spark on your grill, for instance. A gas engine uses sparks to ignite the gasoline. Now ramp that up to the massive energy involved in lightning, and its not hard to see how to can spark up a fire. I'd say that *most* fire on Earth is electrically started.


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

[User] ELI5: Why are employees expected to provide 2 weeks notice when quitting, but employers don't give similar notice when firing people?

[Assistant]
Because firing employees already runs the risk of retaliation of disgruntled employees. And now you want them to stick around for two weeks? With all the physical and logical access they have to company assets and information?

Whereas quitting is mainly you just getting a better offer. The company doesn't pose any risk *to you*, so there is no need for you to severe the relationship as soon as possible. So the two weeks is customary, as it maintains a professional and respectful relationship. After all, they may need to be called upon to vouch for you or you may want - at some point - to return to them.


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

[User]
Do we know anything of prehistoric fruits and vegetables?

Are there any fossils of plants that were once edible or could be edible by humans today?

[Assistant]
The paleolithic is recent enough that not much is fossilized, but also recent enough that genes haven't drifted much, except by artificial selection.

This means that there exists at least one wild plant that is closely related to a recent ancestor of almost any example of a fruit, vegetable, or grain you might imagine.

Apples and pears? Try a haw.

Carrots and parsnips? See Queen Anne's Lace roots.

Swiss chard and beets? Have a small amount of pigweed (it's too high in oxalate for me to recommend eating very much of it).

Artichoke? Look at a thistle...but maybe only cook its thick, fleshy stem, because the flowers are *super* tiny during the stage of development where one would eat an artichoke.

Wikipedia has taxonomic info in the sidebar of each fruit or vegetable article, and can help you find this sort of relationship for whatever else strikes your fancy. Be warned, some things (potatoes and beans, for example) are toxic in the wild type.


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

[User]
[WH40K] Why did the Necrontyr have shortened lifespans after they developed space travel?

According to the lore, the Necrontyr's home star gave out particularly strong radiation (implied to be due to a C'tan), causing the Necrontyr to have extremely short lifespans.  It had a HUGE impact on their psyche as a species.  When they developed space travel and went to other star systems, it seems as though they continued to have short lives.

Why didn't leaving their irradiated home planet allow them to live longer?  For masters of cold science, couldn't they also have turned to genetic manipulation?

[Assistant] Millions of years of evolution. Their life cycle had to be short so the species could reproduce before dying. If they were longer lived then their survival rate drops because now you have less time to reproduce.


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

[User]
ELI5 why Joe Paterno is guilty of covering up for Sandusky and why the recent punishment handed down from the NCAA was just.

The title says it.

[Assistant] Because child molesting is pretty darned serious, and Paterno and the other top brass knew that it was happening, yet decided to look the other way rather than upset their winning football formula and risk losing support from students and alumni. The sanctions are a wakeup call to Penn State and other universities that this sort of thing is BAD and WILL NOT be tolerated. It is a step toward making sure that they don't prioritize football over anything that might harm that program.


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

[User]
[Star Trek: DS9] I thought the federation got rid of money, how are people buying things in Quark's?

I understand that other races may still use currency, but I see Federation officers buying things in Quark's, gambling, there was even an episode where O'Brien was buying fruit pops on the promenade, but it never showed him paying.

Also, it seems like the replimat is free, and has replicators to make whatever food you might want.  Why would you go to Quark's and pay him to replicate food for you?

[Assistant] Remember DS9 is a Bajoran station operated with Starfleets assistance. That being said Starfleet personnel stationed abroad are given a stipend in Federation Credits that have a set exchange rate with Bajoran, Ferengi, Cardassian and Klingon currancies on DS9. The replimat isnt free but uses rations that are given to personnel and civilians onboard the station.


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

[User] ELI5: Why do most modern helicopters have 4 or more blades, while most older helicopters have only 2?

[Assistant]
The Bell 230 and the 212 are mediums that have two blades.

Both those were replaced by 4-bladed versions (the 430 and the 412).

There are many factors that determine the number of blades. But in general, the trend you see in looking at the results of many development programs is this: smaller, cheaper, and slower helicopters have the fewest blades. Bigger, faster, and more expensive ones have more blades.

Notice that the 412 (4 blades) has a max speed about 20 kt faster than the 212 (2 blades).

In general you can say the following:

For hover, low disk loading is most efficient. That means longer blades and therefore fewer blades.

But for speed, more blades are better. The blades turn slower and the tip speed is slower, allowing higher airspeed before the advancing blade tips approach supersonic.

This is illustrated by the 212/412 helicopters.

-The 212 has two blades with a diameter of 48 feet and max weight of 11,200 lb. 100% rotor revs are 324 rpm.

-The 412 has 4 blades with diameter 46 feet and max weight of 11,900 lb. 100% rotor speed is also 324 rpm.

Disk loading
212 = 6.19 lb/ft^2
412 = 7.16 lb/ft^2

Tip Speed
212 = 813 ft/s
412 = 779 ft/s

Vmax
212 = 120 kts
412 = 140 kts

So the 212 has lower disk loading, it should perform better in hover (I don't have data on that). The 412 has lower tip speed and higher airspeed.

Edit: re-wrote it with some numbers to illustrate.


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

[User]
Why isn't the sun used as a gravitational slingshot?

I was just reading about the Helios probes in the 70s, one of which managed to achieve 252,792 km/h (157,078 mi/h) using the Sun's gravity.   On the other hand other probes that use a gravitational slingshot use Jupiter/Saturn, and some attain a quarter of the Helios probe's speed.  Why not use the sun instead?

[Assistant]
The main reason gravitational slingshots work is because from the perspective of the sun, a ship (traveling with velocity V) will enter orbit around a planet (traveling with velocity U) and leave the planet's gravity well with velocity 2U+V.

The trouble with using the sun is that the whole solar system is already caught in the sun's gravity well. And gravity assist is really only applicable to something entering a system.

Imagine throwing a rubber ball at 30km/h against a train moving at 50km/hr. When it bounces, it will have a velocity of 130 km/hr relative to the stationary thrower. You are proposing doing this while riding the train.

The reason the ball bounces from the train at 130mk/hr is because from the perspective of the train engineer, the ball is hurtling at him at 80km/hr, and then bounces away at 80km/hr (from his perspective) add the 50 km/hr and you get 130km/hr from the kid's perspective, or (V + 2U.)


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

[User]
ELI5: Why is it impossible to suck through a straw that's 10.4 meters long?

i understand that when it's too low pressure it starts boiling but what are the numbers as to what gets the 10.3 meters limit, is there any way to increase it through a 0 degree surrounding and a super thin straw? how did they calculate that limit? what are the formulas used?

[Assistant]
The action of sucking does not actually pull on water. Rather, it allows the air on the other end to push by removing the air from the end inside of your mouth.

This means that, since there is only 1 atm of air, you're limited to that much pushing.

As water climbs the tube, gravity pulls it down, generating a pressure to counteract the pushing. This pressure depends solely on the density of water and the height at the top of the water.

So, solving for the density of water, we see that water can only get 10.4 meters above its surface from the action of atmospheric pressure. If the straw goes deeper than the water's surface, then the straw itself can be longer, but the water can only be raised above its surface by that amount.

The formula for hydrostatic pressure is quite straightforward. p =  g h

This is the pressure generated by gravity acting on the water, and it is the pressure that counteracts the pressure of air pushing up. Interestingly, the pressure of the air itself can be found using the same formula (although to get an accurate answer you have to modify it with calculus to account for gravity and changes in density).


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

[User] ELI5:If you were stumble across an undiscovered island, what would you have to do to make it your own country?

[Assistant]
Go to the island. Set up what you need to defend it from anyone else who would want to take it from you, which probably involves cannons and missiles.  Declare that you are a country to other countries and hope that they agree.

That is pretty much it. What areas are countries is up to who recognizes them.


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

[User]
Is Supply and Demand a law that is only valid within our current economic system or is it an actual natural law?

Probably a very stupid question and even more philosophical than economic, but are there theories or even proof that Supply and Demand is a law that applies to nature as well?

[Assistant]
What an interesting question! One way to look at the law of supply and demand is as a law about what the **optimal quantity** to be supplied based on the benefits to the supplier is. If the supplier produces more than that quantity, they will either have a surplus, meaning unnecessary costs, or reduced benefit, since it will have to discount the supply to get rid of all of it. If a supplier produces too little, they miss out on potential benefits.
From the perspective of the consumer, if they consume below the optimal quantity, they're missing out on a trade that would make them better off. If they over consume, they have spent more resources than they like.

To see how this might play out in nature, consider a flowering tree and a bee. The bees are consumers, using energy to fly from flower to flower (price) in order to consume nectar from the flowers. The tree is the supplier, using energy to produce flowers, and gaining the benefit of pollination from the bees (price). If the tree produces too many flowers, the bees will only visit the easiest ones, so there is a surplus. The law of supply and demand doesn't say that the tree will produce the right number of flowers, or that the bee will visit the right number, just that there is an equilibrium value.


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

[User] ELI5: Why does water taste sweet after you've left it on your nightstand all night?

[Assistant] your mouth and the gunk in it that sits overnight, stewing, makes your mouth more acidic and so when you drink a base or neutral, it will taste sweeter than the stagnant situation you've been tasting for hours.


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

[User]
ELI5:why does backing every horse, or it's equivalent, not actually work in practicality in gambling?

Thought this recently when a guy put a fiver on for leicester to win the premiership and paid out for (circa) 75000 - could he have put a fiver on at two bookies, one to pay out with and one to leave on in case they actually win?

[Assistant]
Look at the pay out of the lowest odds horse. If there are 5 horses, five on each horse, is a total bet of $25. If the lowest odds horse wins, pay back might be 5+3, or $8. A net loss of $17.

If he bet only $5 on the horse he thinks is most likely to win, and it does not. Net loss is only $5.

This is only a hypothetical, since we don't know the odds of all the horses in that 1 race. But you get the idea. Keep in mind nobody likes to pay out, especially bookies. So the horse with the highest payoff is the one that the bookies and fellow gamblers think is least likely to win.


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

[User]
CMV: There is absolutely no reason to ever buy med grade gasoline.

Here is the deal.  If you car requires regular gasoline,  there is no advantage to buying anything better.  You car was engineered to run on regular and will gain no performance advantage from anything else.

If your car is engineered to run on premium gas, you will not only kill your performance by putting lesser grade gas in your car, you will run less efficiently negating the cost benefit of the cheaper gas.

I am not aware of any car sold that runs on mid grade.

I would love to know who has a good reason for the existence of  this useless product and who buys it and why.

[Assistant]
The octane rating is also known as the anti-knocking index because it helps prevent knocking (if your engine knocks).

So lets say you have an old car and the piston shafts are getting full of corrosion. Due to the presence of the corrosion, there is less space in your piston shafts. So when the pistons come down on the gasoline, the fuel is compressed too much too quickly and fires early. This leads to knocking sounds in the engine. Switching to a more compressible (higher octane) gas will help prevent the knocking.

Now, it may be that you find that mid grade works fine and so you save a little bit of money versus buying high grade.


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

[User]
ELI5: How did humans learn to extract metal from rocks?

This is something that has always perplexed me. How the hell did our ancestors learn that putting certain types of rocks in 2000 degree furnaces would yield a useful material for weapons and tools?

[Assistant] Certain metals like gold, small amounts of iron, etc. can be found in their natural form without smelting.  As time went one our ancestors learned that other metals could be extracted from rocks by heating them.  Not all metals require insane temperatures to smelt either.  Some of the early attempts could also have been accidental as hearth stones that contained ore were heated and we observed that metal came out of them.


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

[User] ELI5: the difference in sorting comments between "best" and "top"

[Assistant] 'Top' is purely 'highest voted', after the up/down delta. 'Best' takes into consideration much more, like how quickly a comment amasses upvotes, down/up ratio (not just the delta) and some other stuff.


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

[User]
ELI5:Why is romaine lettuce so prone to E.coli?

Thos is atleast the second time this year that and e.coli contamination of romaine lettuce has been in the news? What is it about romaine lettuce that makes it prone to e.coli?

[Assistant]
E.coli O157:H7 comes from one place: cow intestines. Cows are not susceptible to the toxin the bacteria produces. Humans, etc. are. So lettuce has it because cow shit was used to fertilize the plant, or a human who got it from eating contaminated cow meat shit on the plant, etc.

Also, never ever eat ground beef unless it is thoroughly cooked. Always wash your hands very well after handling anything which cow shit or cow intestines might have touched, which is basically any kind of meat or vegetable.

If you give your kids raw milk you should just shoot yourself in the face right now.

Source: kidneys failed due to e.coli.


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

[User]
[Dragon Ball Z] What would have happened if Vegeta and Gohan's battles on Babidi's spaceship were switched?

So Gohan's battle with Dabura royally pissed Vegeta off, causing a sequence of events that ended with him becoming Majin. What would have happened if Gohan had the easy fight against Pui Pui and Vegeta was the one to fight Dabura?

[Assistant] I don't think much would have changed, Vegeta's power lust to surpass Goku wouldn't be wavered by beating Dabura. Vegeta became Majin because it was another path to power, if the offer still stood after he beat Dabura, he would still take it to try and beat beat Goku in the end.


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

[User]
Theoretically, what would stay cooler in the sun: a container that is pure white, or a container made of mirror?

Aren't both objects reflecting all light?

[Assistant]
In an idealized case, no difference.  The only difference between a mirror and "white" is the *direction* that the light is reflected.  The amount of absorption is the same.

In practice, the mirrored one would stay cooler.  This is because practical whites are less reflective than high-quality mirrors; part of reflecting light in random directions is that sometimes they reflect light inward and absorb it.

Also, mirrored surfaces usually reflect non-visible wavelengths well.  White diffusers more commonly have a limited range of effective frequencies.


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

[User] ELI5: If strings and quarks exist, why are atoms called the building blocks of matter?

[Assistant] Because the atom is the fundamental unit of *chemistry.* Pretty much everything interesting in the universe happens because of chemistry, and chemistry happens between atoms. The smaller constituent parts quarks and gluons; strings are just a metaphor and don't actually exist as tangible things even if string theory is valid do their own thing, but they don't participate in chemistry.


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

[User]
eli5 What is the added value of garmin (and other) GPS navigators

Basically this. Even the cheapest phone has GPS and Gallileo chip capable to track your location. Do standalone navigators offer better precision and reliability? Do they have better anthennas ans more sonsitive detectors? Why do hobby pilots and boat captains always use Garmins?

UPD. We have a lot of ratheer simplistic answers aka "Garmin doesn't need cell coverage" or "Garmin has better maps" which is simply irrelevant since you can install any map on android as well (even official ones from Garmin) and use it offline. I'm sorry for formulating the question poorly, but I meant what are technical differences between phone GPS chip and standalone. Are they better (more accurate and fast) at getting location and how is it achieved.

[Assistant]
If you already have a smart phone, then they can provide a lot of the same functionality as as GPS. If you don't, then GPS units are far cheaper. That said, a dedicated GPS unit has a number of benefits over a GPS app on a phone:

1. As a dedicated device, all of the battery in a GPS is powering a single thing. Thus the battery is likely to last longer than a phone which will have things running in the background and will be constantly draining power as you use it for other things.
2. ~~You can preload GPS units with maps of wherever you are going, which will then therefore work wherever you go. Phones, on the other hand, will have to download maps on the fly, which requires you to have cell phone service or wifi. So if you are in a place with no internet, the GPS on your phone won't do you much good because you won't have the corresponding maps to use it with.~~
3. Since there is little concern about needing the device to fit in a pocket, you can buy GPS devices that are larger and therefore easier to read and use.
4. GPS communication is one way. The device receives information, but doesn't upload anything unless you deliberately and manually do so. So if you are concerned about data privacy, a dedicated device is the way to go.


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

[User]
ELI5: How is tap water not full of mold and algae when nobody cleans the inside of the pipes that carry it?

Anything wet that I leave outside accumulates mold, algae, and other gross stuff over time.  Given that drinking water pipes are not regularly flushed out with bleach or something, how is it that drinking water is not totally filthy from going through dirty pipes?

Edit: thanks for all the responses guys!  Especially from the water treatment and plumbing experts.  Didn't expect to get such a big reaction!

[Assistant]
> drinking water pipes are not regularly flushed out with bleach or something

They are, essentially. Drinking water supplies contain a low concentration of chlorine bleach or another disinfectant to prevent germs growing.

Also the pipes are sealed, with valves and taps designed to prevent air containing germs being drawn in, and they're opaque so light algae need to grow doesn't get in.

EDIT: As many people have mentioned, not all places and countries leave the disinfectant in the water. Ensuring that it's clean when it enters the pipes - either with chemicals that are removed or with UV light - along with the pipes being airtight and dark and unfavourable to life is when done correctly enough to keep the water clean.


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

[User] ELI5: How do we actually know what colours other animals can or can't see?

[Assistant]
The rods and cones in your eyes contain dyes, which are the chemicals that do the light sensing.  A dye is just a molecule that absorbs a very specific frequency of light.  This makes them a particular color, and you can literally just measure the light reflected by these dyes to see what color they absorb.

These molecules also bleach as they absorb light (which is how they adapt to brighter light), so you can also see what color light you have to shine on them to make them change color.


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

[User] Is a submarine, which is able to withhold pressure from the outside, also able to withhold pressure from the inside, ie. space.

[Assistant]
While submarines are not specifically built to withstand internal pressure, they can withstand an immense amount of pressure, far more than the pressure differential between space and atmosphere.

The pressure of space is 0 psi (no atmosphere) compared to about 14.7 psi (atmospheric conditions) that would be inside the vessel.

Compare that to the pressure under water.  Every 10m of depth is approximately equal to one atmosphere increase in pressure.  Modern subs have a collapse depth of well over 500m.  That is 50 times greater pressure differential than that in space, over 700 psi.

The major difference between the two examples is that the pressure is internal in one and external in the other.  While design considerations are made for the two pressure differentials, the substantially larger pressure requirement for subs would mean that it would certainly be able to withstand the pressure differential in space.

One last note: From a practical standpoint, there may be pressure regulators on a sub that are meant to remove pressure from the cabin that would malfunction if outside pressure is too low.


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

[User]
ELI5 what "eye boogers" are, and what purpose do they serve?

My mom used to tell me I still had sleep in my eyes as I was eating cereal before school. When I asked what it was, she said it was dried tears from my yawns.

No idea if that's the real answer, but lately I've had trouble opening my eyes at all in the morning because I've got so much of it.

Where does it come from and is there some biological or evolutionary purpose behind it?

[Assistant]
In a nutshell, "Eye Boogers" ("rheum") is mucus mixed with blood cells, dust, skin cells etc. This mucus is called "Gound". This gound helps seal your eyes in an air tight fashion when they are closed, prevents tears from spilling onto your cheeks, and helps keep tears that coat your eyes from evaporating.

Gound naturally disappears when blinking or on touch, but since you're not blinking at sleep whatsoever, this gound fills up and causes "eye boogers".


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

[User]
[Star Trek 3] Why didn't the Enterprise's self-destruct blow up the whole ship?

It seems that the self-destruct explodes the bridge, and then a few seconds later, the saucer section. The rest of the ship tumbles into the atmosphere, which certainly destroys it, but I wouldn't think the computer was planning on that to happen.

A dedicated destruction for the bridge would make a certain amount of sense, but why not just detonate the warp core like the Enterprise-D does?

EDIT: After thinking for a bit, the ship is extremely damaged at the beginning of the movie. It's possible the self-destruct just didn't work properly.

[Assistant]
The primary purpose of the self-destruct system is to prevent sensitive information from falling into the wrong hands. While the complete destruction of the ship is usually the desired outcome, it is not fully necessary (or even possible due to the limitations of the conventional charges in place). The conventional charges on board were nowhere near enough to destroy the entire ship, but they are located to trigger secondary explosions of the ship's warp, impulse, power grid and fuel system.

The 1701-nil had taken significant damage in the battle against the Klingon, and as a result her warp core had automatically shutdown and purged to prevent a catastrophic breach. Without an active core, the self-destruct system was much limited.

The charges in the saucer section detonated the fusion reactors that were still online as intended, resulting in a secondary explosion sufficient to destroy that section. However, it seemed several of the charges failed to go off, particularly those meant to destroy critical engineering section components and breach the antimatter containment system.

It's worth noting that the ship had been rushed back into service after two serious engagements, only to stumbled into a third, so even though the self-destruct system is independent of the main system, it's likely to have seen some damage as well. It's also possible that the self-destruct system had its command and control network poached for spare parts, since the system would've been viewed as expendable in trying to get as much of the ship back online as possible, especially after her 'theft' deprived her of Starfleet technical assistance.


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

[User]
ELI5: When light hits an obstacle, where do the photons go?

(Great answers, thanks all)

[Assistant] Some are bounced off and hit your eye, we call that seeing. Some bounce off and hit other objects. Some do the thing that photons can do where they behave like a wave instead of a particle and get absorbed by the object, heating it up.


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

[User] ELI5: What makes the number e so special and why is it used as the base of the natural logarithm?

[Assistant] e is so special because the y coordinate of the function y=e^x at a certain point is also the slope at that point. So the slope at x=3 will be e^3. This property of e and the natural log are very useful when solving problems in calculus involving exponents and such.


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

[User] ELI5: Why are clothes of different sizes the same price? Are the price mark-ups from the manufacturer big enough to neglect the cost of the extra fabric in larger clothes?

[Assistant] The cost of the fabric is only one of many components that go into the price of an item... a $20 t-shirt may only have $2 worth of fabric in it, with the costs coming from labor, transportation half way around the world, distribution to stores, branding and design, mark-ups for the various middle men along the way. So maybe the small has $1.80 worth of fabric and the XL has $2.20 worth. They set the price at the average cost, which is easier than having to set, input, track countless prices for all the different sizes. A store having to spent 4x as much time setting prices would spend far more on labor doing that than is spent on additional fabric.


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

[User]
CMV: Blue Laws surrounding the sale of liquor and beer are old & antiquated, and have no purpose other than to uphold the status quo.

I live in Texas. A state that has extremely outdated Blue Laws that prohibit the sale of liquor past 9PM (M-Sat), and require all liquor stores to be closed on Sundays. Not to mention, you can only buy liquor at a designated liquor store (although you can get beer and wine at grocery stores, convenient stores, etc.)

It makes no sense in a free market, capitalist society (especially in a Red State) that these laws exist. They prohibit the sale of goods to a market that clearly exists, and it feels borderline unconstitutional considering many blue laws have religious origins and/or influences.

This pious paternalism by blue law states has given way to a ridiculous protectionist argument. Look no further than the owners of various liquor stores (or chains) who worry that competition will force them to work harder without guaranteeing a commensurate increase in revenue. Which is bullshit.

It appears the only thing Blue Laws want to protect are the establishment, not the consumers. We can still walk into a bar on Sunday (past noon) and get rip-roaring drunk, etc. So please, challenge me here. Change my view. Why are Blue Laws good? How is this a free market concept? I can vote. I can get drafted. But God forbid I want to buy a bottle of Pappy on Sunday. THE HORROR.

[Assistant]
\> They prohibit the sale of goods to a market that clearly exists

This is, surprisingly, actually a misperception.

It's often not conservative, puritan people who want liquor sales outlawed on sundays, but the *liquor stores themselves* which exist in what they understand as a conservative area. If it were legal, then to compete with large grocery chains, small liquor stores would have to be open on Sundays and lose money as a result.

You could actually argue that these laws protect small businesses from losing to big ones.


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

[User]
[Dishonored] How are the talents of a Mark-bearer determined?

Daud and Corvo have slightly different talents from one another. Granny Rags and Delilah both have wildly different abilities to either of them, and yet all of them possess some form of Blink or Blink-like ability.

Does the Outsider tailor a person's talents? Or does the Mark simply awaken magical aspects already within a person?

[Assistant]
> Does the Outsider tailor a person's talents?

This seems the most likely. After all, the Outsider is very, *very* bored, and basically omnipotent. He might give them abilities matching their wildest dreams  so that he can savor the irony of their inevitable defeat. Or he might give them abilities that are likely to cause the most destruction so that he can revel in the chaos and further his ineffable goals. In Corvo's case, it appears to have been both simultaneously (since the Outsider didn't know which path Corvo would take).

Note that the protagonist of Dishonored 2 has been shown to have a kind of grappling tentacle thing, time stop, and some kind of monstrous transformation. Also note that there are some differences in the behavior of Corvo's and Daud's blink abilities.


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

[User]
cmv: defunding the police is quite possibly the dumbest PR move ever by liberals. they've taken something almost everyone would support on some level and turned it into a right wing talking point.

usually when you run a marketing campaign, you want people to know your real plans. with the whole "defund the police" movement they've done the exact opposite and, turns out, it's not a brilliant move. people center/right take it literally. and why wouldn't they? it's pretty clear. and there's enough young angry 20-somethings out on the street reinforcing that literal interpretation. clearly their own advocates don't even understand the real message.

if the idea is to shift funding away from expanding police, who treat the symptoms (crime), to investment in strong communities. THEN SAY THAT. and to anyone who actually wants to defund the police, please be an adult. that's not realistic. humans suck. what we need is investment in communities, not prisons. and these asshat "defund the police" commies are completely undermining something this country desperately needs.

[Assistant]
I don't really understand what you expect to happen. There is no liberal PR department. To the extent that the Democratic party is trying to control messaging, Biden has repeatedly said he's opposed to defunding the police.

Right wing news sources will blatantly lie or misrepresent about what liberals do, say, or want. So it's a little annoying to blame "liberals" for being too nuanced when it frankly doesn't matter what they actually say. Trump, Tucker Carlson, etc will just make shit up anyway, or will amplify whatever voices they find convenient, regardless if if those voices actually represent the majority of liberals. It doesn't matter if a million or a hundred liberals are saying something. They can do their segment based off one guy with a sign.


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

[User]
[Harry Potter] How does the Hogwarts support hundred of owls?

In Harry Potter, it seems like the majority of students have pet owls. Starting every September, hundreds of owls are brought to Hogwarts, and presumably left to hunt most of the time. How do they grounds support this sudden influx of predators. Even the forbidden forest must get hunted clean after a few months, with so many owls hunting the same areas. I imagine that there aren't usually that many owls concentrated in one forest.

Plus, especially in the winter prey must be scarce, there's no way that there's enough to go around. If they're fed by the school, where does that come from? Is Hagrid importing then slaughtering barrels full of bunnies and rodents?

Also, what happens if an owl flies into the forbidden forest and is caught by some giant spider? Does Hogwarts have a policy for pets that are killed at school? Owls can be expensive for some families.

Edit: Dammit not "The Hogwarts" I meant the Hogwarts grounds in the title.

[Assistant]
someone walks upstairs each day and casts the refilling charm and the scouring charm then after that 10 second chore is over they go back down stairs.

unless of course it is filches job then it takes hours of back breaking work, which he does because he doesn't have any other choice.

edit, owls won't eat pet food but they will eat raw meat and i'm almost sure there is some charm to keep meat fresh.


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

[User]
Why pointers?

I have been getting into learning C++.  I am not a beginner to programming, but I am only around intermediate, at best.

I have followed many tutorials and videos on how to use pointers and references, and have a pretty good grasp on them.  However, none of the videos or tutorials seems to teach when or why they are used or why they are useful.

I've done a lot of searching, but I cannot seem to find a reason why they are such a great thing.  I believe they are, but just want to understand the 'why' of it!

So, as my title says: Why pointers?

Edit: Thank you to everyone who chimed in on my post.  I feel I have a much better understanding now!

[Assistant]
> Why pointers?

If you have a big chunk of data you need to pass to a function, would you like to create a copy of all that data and pass it (i.e. passing by value), or just pass the address of it (i.e. passing by pointer)?


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

[User]
ELI5 Dust

What is it, where does it come from, etc.

[Assistant] Dust is particles of various things that are light enough to be kicked about in the air. Dead skin cells, small flakes of things; they are picked up by air movement and travel around. Over time they accumulate on surfaces, which is why the longer something sits somewhere, the more dust ends up on it.


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

[User]
[Mad Max] What year is it?

<SPOILERS!!>

How long has the world been destroyed? Also how old is Max? How has he been able to survive the cancers? Everyone else that remembers the world is old and/or horribly deformed yet in the beginning Max says he was a cop, so are there pockets of civilization and Max's fell? Or is he some immortal mutant?

[Assistant]
> Everyone else that remembers the world is old and/or horribly deformed yet in the beginning Max says he was a cop, so are there pockets of civilization and Max's fell?

This is answered in the first Mad Max film - Max was a 'cop', but he was part of the Main Force Patrol, which was formed after society had begun to break down. So he wasn't a cop in the sense that we might know them, but a near-future patrol officer charged with breaking up the biker gangs that terrorised the countryside. With that said, in the first Mad Max film, civilization is still going, albeit limping along.


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

[User]
[Harry Potter/ MCU] What would Red Skull call Voldemort?

Inspired by a post about Voldemort on Vormir.

What would Red Skull call Voldemort?

We know that the Guardian uses the most influential person in someone's life like when he called Hawkeye "Clint, Son of Edith" because his father wasn't around much.

So what would he call someone like Voldemort whose parents weren't around and who wasn't adopted? And would he call him Tom, since he doesn't care about Aliases?

[Assistant]
You forget that he called Natasha "daughter of Ivan" when she didn't even know her father's name.

So, in actuality, we don't know the rationale behind what he chooses to call the person. So it would call him "Tom Riddle" son or daughter of whoever.


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

[User]
[Futurama] Why are Fry and Enis so similar? *spoilers on 14 yr old episode*

In the episode "Roswell that Ends Well" we learn Fry is his own grandfather by doing "the nasty-in-the-pasty" (love saying that). Logically he should have no real relation to Enis, his supposed grandfather. Why do they resemble each other so much then?

[Assistant] As Mildred said, Fry reminds her of Enis. She has a thing for dopey but well meaning guys. She lost one but the very next guy is extremely similar so she latched on. If it wasn't Fry, it would be someone similar to both him and Enis.


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

[User]
[Marvel Comics] How much does the average citizen actually know?

There's a lot of weird stuff in 616. Atlanteans. A blue area on the moon. Moloids. Inhumans. Deviants. A new alien invasion every other week in the 60s (or early 2000s if you go by the sliding timeline.)

How much does the average citizen know? What's secret? What's generally known? What's known only to top secret government officials? What's entirely unknown but to the few involved? I'm not just talking about the stuff mentioned above, I mean almost literally everything.

What kind of world do they think they live in?

[Assistant]
Like time travel, this is one of those fictional subjects that you best not scrutinize too deeply or else you'll get frustrated.  Or, if you're like me, you'll be reminded by how lovably stupid comic book worlds are.

For example, at one point the public knew that Peter Parker was Spider-Man.  Then he made a deal with the devil or some shit like that and now nobody knows who's in the spider tights.  What was common knowledge to the average 616 citizen in 2006 was back to being a secret in 2007.

Also, the entire Marvel multiverse just got destroyed and rearranged.  So what the public knew before the universal collapse likely got changed as well.

Then there's stuff that the public *should* know if we went by real-world logic, yet they don't because it would screw things up for comic book writers.  For instance, many of the things invented by Marvel's geniuses - Hank Pym, Reed Richards, Tony Stark, etc. - get flown around major cities on a daily basis.  The Fantastic Four has a flying car.  Stark has an army of robots doing various tasks at his company.  Doom has his Doombots.  Pym created an AI that regularly tries to take over / destroy the world.  Etc.

You'd think the public - at least those in NYC - would have access to flying vehicles, or the police would be carrying energy weapons supplied by the Avengers or something.  You'd think NYC would be a technological utopia like what we see in *Star Trek*.  Nope!  John Q. Public is still driving around in Honda Civics; those poor beat cops still try and use revolvers to stop Electro when he breaks into a bank; Hell's Kitchen is still a shit hole; and NYC overall looks like what readers can see in the real world.

TL;DR: What the average citizen in a comic book world knows changes regularly.  And what they do know doesn't make sense.


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

[User] ELI5: The Associated Press (AP). What the heck is it? Do they have their own journalists? Are they a news agency? Where do they get their stories from?

[Assistant] Okay, you're a hotshot news editor for the Middle School Times, right? There's a friend that you have that also owns a news paper in the next town over, the Middle School Edition. Then there's a third paper, the Middle School Chronicle, that has a story that you and your friend want for your respective papers. So you go to the Chronicle and cooperate with them, creating a newspaper organization that allows you all to share stories with each other, re-writing or tailoring parts of the story to fit your specific paper but keeping the bulk of the story. Additionally, this new organization hires specific staff to write general stories for the three papers to all use. That's what the AP is, a cooperation of a lot of papers radio and tv stations throughout the country, which allows it's members to use stories from various locations and written by various individual news organizations that are part of the cooperation.


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

[User] ELI5: If a battery sits without being used for a long time, it loses charge. Where is this energy going?

[Assistant] 90 percent of the time, if you arent sure where your missing energy is going, its being used to create heat. In the case of batteries, this is slow enough that you wouldnt notice the increased temperature without using one of the most precise thermometers available and heavily insulating the battery.


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

[User]
[LotR] Why would Elrond allow Boromir, a man who has clearly shown interest in the Ring, to join the Fellowship?

I know that Boromir was a noble man and an excellent fighter, but still... This is a quest that's already borderline impossible, and it seems like a massive risk.

[Assistant] Politics - Boromir was the rightful representative of the Kingdoms of Men, sent personally by the Steward of Gondor.  Elrond had no authority to prevent the Fellowship from forming nor does he control its composition - hence why Merry and Pip are allowed to join with a minimum of consternation.


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

[User]
ELI5: Why is dry firing a bow so harmful but adding an arrow makes it safe?

How does adding an arrow change the weight?

[Assistant]
Normally, the potential energy stored in the bow by the action of pulling back the string is all applied to the arrow you shoot.

If you release the string with no arrow to receive all the hullabaloo, this energy is instead transferred to the bow itself, which cam be enough to break or shatter it, causing splinters in the eye or even a cut up hand or arm.


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

[User] ELI5: Why our eyes redden when we cry even when we don't rub them with our hands?

[Assistant]
The process of crying involves inflammation, size increases in the blood vessels in the eye (vasodilation) and water retention.

It might also involve thousands of tiny salt knives chopping up your eyeballs, though. Who knows.


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

[User] If pushed, would a frictionless marble roll across a surface or glide?

[Assistant] If it was pushed in-line with its center of mass it would glide, and if it was given some torque as it was pushed it would have a rolling component, but it wouldn't roll without slipping, which is what most people mean when they think of rolling.


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

[User]
[The Good Place] Doug Forcett's Points

How was Doug Forcett still able to accumulate points after he became aware of the system? It's explicitly stated that Doug's entire goal is get as many points as he can in order to get into the Good Place. It's also explicitly discussed that angling for moral dessert is a corrupt motivation, and doesn't net any points. Yet Doug still manages to have a pretty hefty point total compared to other people. How?

[Assistant]
Cause he still didn't actually know for sure. He was just putting his faith in a guess about how the universe and afterlife could work, like most everyone else on Earth.

It just happened to be the most extraordinarily accurate guess in human history.


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

[User]
[LOTR] If the first king of Numenor encouraged scientific research, how would the events play out by the time of the last alliance?

Assume subsequent kings also supported research.

[Assistant]
What makes you think they didn't?

The Numenoreans were *by far* the most advanced civilization throughout the stories we see.  Their construction of buildings alone would make them this, but the also made great advancements in ship building and medicine.


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

[User] ELI5: How do game programmers develop a game for console if its not playable on PC. Mainly in testing if the code is working, is there a developer console that bridges the gap between pc code and actual consoles?

[Assistant]
Yes, console manufacturers make developer consoles.  Usually you can load games over the network, attach debuggers, take screen caps, gather performance data, and such like that.  They may actually have more RAM and CPU power than a normal console, in order to support these functions while your game is running.

Of course, you usually can't connect to any online services with them because it would allow massive hacking.


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

[User]
Can you fuse any two pieces of the same material in space just like metal?

We know that on earth here when we cut two pieces of metal the freshly cut surface oxidizes preventing the metal from joining back together,

Though in space the metal does not oxidize and is able to fuse back together into a single piece of metal,

My question is, is this the case for all material? For example wood, (I dont know why we cant fuse that back together on earth) if we took a piece of wood to the vacuum of space could we fuse it back together just through pressure?

And if we cant, can someone explain why we cant?

[Assistant]
For this kind of cold-welding process to work, you need a few things to happen:
1. The two surfaces have to come into atomically close contact, with relatively few gaps between the materials, to form a strong bond at the interface to be joined.  In other words, the atoms or molecules have to be in close enough contact to form a chemical bond.
2. Once in close contact, a large fraction of the atoms have to be chemically capable of forming bonds with each other.

Metals often satisfy these two conditions because they behave something like atoms floating in a sea of electrons, with a lot of flexibility in the spatial arrangement of the atoms.  This makes the metals malleable (edit: and more importantly, ductile), so the interfaces can be smushed together to remove most gaps or imperfections at the interface, especially if there is no air in the way.  Cant do that with wood, which has a more rigid structure (made mostly of organic molecules that are much more specific in their spatial bonding geometries) that cant be deformed much from its equilibrium structure.

Also, since metal atoms can easily form metallic bonds with many neighbors, which are often the same kind of atom, one part of the surface will look much like any other, and you dont have to match the surfaces perfectly with respect to binding partners.  Every atom at one surface could pretty much bind any atom of the other surface, with little reorganization needed.  Wood, on the other hand, is a complex mixture of organic molecules comprising carbon, oxygen, nitrogen, hydrogen, phosphorus, and other elements that bond with each other in rather specific ways.  For any given atom on a surface, its unlikely itll find itself next to an atom on the other surface that is capable of binding to it without significant input of energy (and probably catalysis of some kind).

So, with wood, there will be significant gaps throughout much of the interface, and most of the parts that do touch wont be reactive with each other.  So, no bond will form.


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

[User]
Now that banks have zero reserve requirements, how will this amplify the money multiplier effect?

I've read that the money multiplier formula is 1/r. When the RR was 10%, $1 in deposits = $10 created in the banking system. If the reserve requirement is 0, then won't this allow for unlimited money creation?

[Assistant]
We have different ways of regulating banks now.

We don't have a "reserve requirement" but we have max leverage and regulatory capital requirements that effectively require banks to hold reserves sufficient reserves.


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

[User] ELI5: How did no one notice that tens of millions of cars were not meeting their emissions standards until now?

[Assistant]
They were meeting their emission standards. That's the whole scam.

I assume you're asking about the VW situation going on now.

The software that runs in the computer that controls the engine and emission control systems was written to detect when the emission tests were being performed and *only while the tests were being performed*, to reduce the car's emissions. During the periods of emissions testing, when the computer put the car into low emissions mode, the performance of the vehicle, mileage, acceleration, etc., went way down. When the software did not detect that an emissions test was being performed the computer boosted performance and emissions went through the roof. This meant that when they were doing emissions testing they got great emissions results and when they were separately doing performance testing they got great performance results. They advertised both the emissions and performance results and people expected, reasonably, that the configuration of the vehicle was the same in both tests which it was not.


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

[User]
Who has a greater epigenetic contribution, the mother or the father?

My limited understanding of epigenetics is that it refers to changes in gene expression, not due to changes in the DNA itself but instead via mechanisms such as DNA methylation and histones, and that these changes may be heritable. It is therefore possible for behaviors during an individual's lifetime to alter the gene expression of that individual's offspring. As far as I can tell, both parents contribute to epigenetics.

I was wondering, since the sperm and ova are quite different, are the epigenetic changes equally well preserved for both parents? To put it another way, does the prior lifestyle of either parent have a greater bearing on the gene expression of the child?

[Assistant]
I think you're asking the question too early - we only know a handfull of imprinted genes, in which the gene from one specific parent is always disabled.

But yes, epigenetic changes are equally well conserved, in that you always get one set of marks from your mother, and one set from your father - however, which parent's epigenetic marks make the greater impact is something we won't know for a while.

Source: work in an developmental epigenetics lab as a bioinformatician.


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

[User]
Why is Iran so heavily forested in the north?

Looking at google maps, Iran seems to have a stark change in it's climate and ecology just north of Tehran. What causes this?

[Assistant]
There's a low point from the Caspian Sea that leads south to a mountain range. Most moisture from the sea comes down here as rain.

The rest of Iran doesn't get much precipitation, and the places that do mostly get snow.


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

[User]
CMV: The first woman president getting there because of the 25th Amendment is not a good look for female empowerment.

I've seen conservatives on Twitter trying to invoke the 25th Amendment after a clip of Joe Biden at the end of a press conference "looking confused" and the staffers asking the reporters to leave.

I don't think Kamala Harris, potentially the first female president getting to that office would be considered a success for the female empowerment movement. There would be a side note on her that detractors can say "she only got there because a man had to drop out". This would be similar to Mackenzie Bezos being the richest woman because she got half of Jeff's fortune. Detractors are saying that the man did all the hard work.

It would be better if the first woman president runs a successful primary campaign and wins the election as that says more about the nation than getting there through some roundabout back door.

edit: I wish I could see comments on why this is getting down voted.

[Assistant]
Regardless of how a woman becomes the first president, there are going to be people complaining about how it happened. Yes, in this case people would say "blah blah only the 25th", but if she got elected in a campaign there are going to be people saying "blah blah, she only won because people voted for a woman, not because of her competence, sexism against men blah blah".

And becoming president by the 25th isn't some "roundabout back door", it's explicitly written into the system. She got elected Vice-President with and thus as a possible successor to Biden if anything happened.


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

[User]
What would space look like if WE were the furthest planet in the furthest galaxy in the universe?

I think the answer to this is 'no one knows', but I thought I would ask you guys to be certain.

As we are in the middle(sort of) of a galaxy in the middle(sort of) of the universe, when we look out to space via telescopes or the naked eye, we see stars and galaxies and black/nothingness.
My question is what if we were the furthest galaxy, on the edge of the known universe? What would we see when we looked up and out?
Nothing? An unknown?

My way of thinking is that because we would be closer to the edge of the universe, light would not yet have travelled to the point we would be looking at. Am I right in thinking this? So therefore we would be unable to see past a certain point?

[Assistant]
It would *most likely* still look more or less the same. If we were to be on the edge of our presently observable universe, we'd be at the center of some other observable universe. There would just be more galaxies and stars. As it stands, we are in fact, at the exact *center* of our observable universe. But every point in space is the center of its observable universe, that's kind of the point. The observable universe is just all of the points in space-time that have had a chance to send light to your point in space-time.

It gets debated on here *ad nauseum* but the scientific consensus view is that the universe is *very likely* to be infinite in size.


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

[User]
ELI5: Why does putting lemon/ lime juice on fruit keep it from browning?

I've always wondered why lemon juice slows the browning of fruits (apples, avocados). If this had something do do with the surface being exposed to air, wouldn't any type of liquid/ solid barrier work?

Thanks!

[Assistant] Oxygen reacts with a chemical (polyphenol oxidase) in plants, this reaction leaves the fruit brown (kind of like rusting). Lemons and other acidic fruits have ascorbic acid which also reacts with oxygen. The oxygen reacts with the ascorbic acid instead of the polyphenol oxidase until the acid is used up.


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

[User]
Why is Luke dragging Vader in the end of Return of the Jedi?

I just learned of this sub (thanks to bestof) so I thought I would ask a question that has bugged me since the 80's. I'm not a huge fan of science fiction but do enjoy some so excuse my ignorance.

Question: Why in the end of Return of the Jedi does Luke drag Vader while trying to get him off the Death Star? Why doesn't he just use the force to carry him?

[Assistant]
Even by that time, Luke was not proficient enough in the force for such fine control like that. He received very little formal training, almost a crash-course in being a Jedi. He'd lifted rocks before but not consciously and with any control, and his emotions broke his concentration and he dropped them.

He was very emotional at the time, just having witnessed his fathers act of redemption and mortal wounding. He was in no mindset for such control. Mentally exhausted,not to mention being physically exhausted.


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

[User] [Matrix] How did Neo use his abilities outside of the Matrix?

[Assistant] Remember the Architect's Speech at the end of Reloaded? He says Zion is a holding pen for the people who can't conform to the Matrix. That never sat right with me. The machines just let the humans into the real world? Where they could do real damage to the machines? No, they created a second Matrix, one that has a different programming that will allow the rebels of Matrix Prime to conform. Neo realizes this, but doesn't reveal it to anyone (it would invalidate everything the People of Zion fought for) thus allowing him to use special abilities in the "real world."


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

[User]
How do animals think if they can't speak?

I mean, I know how they think, they think with a brain. But do they speak in language or pictures? An English person thinks in English. A Russian person thinks in Russian. A Chinese person thinks in Chinese. A Spanish person thinks in Spanish. Bugs, mammals, insects, animals in general, cannot speak. They make noises occasionally, though. But how do they think? Do they think in pictures? If they can't speak they probably don't know languages, so they don't think in languages, right? How do they think, or do they at all?

[Assistant] Well, first think about your thoughts. Do you always think in terms of language, or do you sometimes think in terms of wants, and wishes? Such as, you feel thirst, and the image of a glass of water flashes in your mind, and it pleases you. Or you need to jump across something, and it just doesn't feel like you could make it. Not all thoughts are complex enough to require language.


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

[User]
Do cellulose based plastics pose any of the same hazards as petroleum based plastics?

If not, is the only reason for not switching to primarily cellulose plastic money?

[Assistant] Cellulose-based plastics were some of the first "plastics" discovered. Although there are constant innovations, the cellulose backbone just doesn't work in all the situations we need it to. That's why we made others. Further, many of them are not biodegradable and most require petrochemicals to make anyway.


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

[User]
Did not receive all the reviews for a rejected article....

/rant, sorry!

Waited 4 months for peer review at a pretty prestigious journal. Got a rejection... The rejection letter said

"The Reviewers' comments on your work have now been received.  You will see that they are advising against publication of your work.  Therefore I must reject it."

BUT they only provided reviewer 3's comments and they were pretty favorable. I am NOT salty about the rejection (I kind of knew it was a long shot).. but to not provide comprehensive feedback from all the reviewers is a miscarriage of the whole peer review process, IMO.

Then I get a feedback form (generic) from the publisher - a survey about author services. Many strongly worded comments were made.

EDIT: Yes, I have asked twice, using the 'correspondence' function in the editorial manager - with no response at all. Am thinking now I may need to go another route, maybe find an actual email address and reach out? Thoughts?

[Assistant]
I know for a fact (Elsevier's review workshop) that the Editors are recommended to cut out very harsh reviews for obvious reasons. That could be one issue.

Another possibility is that the reviewer wrote directly to the editor pointing at a fundamental issue with the submission without referring to the authors.

It is also common that the handling editor does not wait for all reviews and rejects as soon as one of the well-trusted reviewers of the journal rejects.

The other possibility is that the editorial office mistakenly did not include all review letters because, for example, some reviewer did not fill out the online form but instead sent the review letter per Email's attachment.


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

[User]
[Final Fantasy VI] Why are there so many random animals encountered that can use very high level spells despite most inhabitants can't use a link of magic?

While adventuring through the land I discovered a forest full of Dinosaurs. I fought many Tyrannosaurus and Brachiosaur while in there and was pelted with many a Meteor spell and Ultima spell. How is it that these random animals know such powerful spells while I can only use my weapons provided. Are these Dinosaurs espers or something?

[Assistant]
Yes, magic-using animals are all part-Esper.  They've either been directly breeding (as we saw with Maduin and Madonna, Esper breeding is magic-based, rather than biological) - or they've eaten bits of dead Esper.

The "Dinosaurs" You're seeing are actually a kind of Dragon, and Dragons are a species of Esper.  They're not quite as powerful as the great dragons responsible for the Crusader seal, but they're significantly more numerous, and still a force to be reckoned with, as you've discovered.


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

[User]
ELI5: Why do some appliances say not to plug them to an extension cord but rather directly to a power source?

Also to add, will there be a difference if its plugged directly to a power source vs it is the only thing plugged to an extension cord?

[Assistant]
Appliances that draw large amounts of current (like a microwave) can potentially exceed the rated current of a wall outlet if there are multiple other things plugged into the outlet. They might also draw more current than a (cheap) extension cord or power strip is rated for. Mostly, though, they just don't want you using an extension cord or power strip because it'll encourage you to plug more things into the outlet.

If you have an extension cord that is rated 15A or higher, then you should be able to plug just about any 120VAC household appliance into it without an issue (just don't leave a long extension cord coiled up while you use it- they can overheat that way).


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

[User] [Star Wars] How do they keep Droids from becoming true sentient AIs and killing everyone? Were there ever truly sentient AI machines?

[Assistant]
So why does everyone assume a sentient AI is going to kill everyone?  There were plenty of sentient droids around.  For the most part they're friendly and enjoy their work.  Droid rights aren't really what you'd call adequate in the Republic and certainly not the Empire, but droids get along anyway.
And beyond that, even if a droid got it in his head to start killing everybody, the same things that protect against biological sentients from doing that are still in effect.


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

[User]
(Marvel) How do Asgardians know English?

I am wondering because they know English but they are Norse Gods.

[Assistant] They aren't actually Norse Gods - they're a race of aliens so advanced that their technology, for all its Viking motifs, appears magical to us.  This includes their implementation of Universal Translators.


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

[User]
[Santa Claus] How damaging is Santa's activity to the legitimate manufacturers and retailers of toys?

It is common knowledge that the night before Christmas Santa Claus visits the home of hundreds of million (if not billion) children providing them a variable amount of toys for free with the sole condition of them being considered "good" on his personal evaluation.

Interesting enough, Santa is not only a distributor of toys: his headquarter in the North Pole houses a state of the art factory where a workforce composed entirely by elves produces directly the toys that are being carried by Santa on his slay. Considering that to please modern children Santa no longer delivers generic toys (teddy bears, wooden trains, rag-dolls) but branded toys from major companies (Barbie Dolls, Lego, game consoles) we can deduce that Santa's toy factory is capable of producing perfect imitations of all the toys on the market (including boxes, serial numbers and instructions) violating every conceivable laws of intellectual property and copyrights.

That being said how hard are damaged the legitimate companies producing and distributing toys by the unfair competition provided by Santa? The old man distributes toys for free to hundreds million of households in a period where the general public is in a spending spree, denting severely the market share of the toy makers and distributors and, even worst, he produces perfect imitations of established brands.

I can begin to quantify the amount of the economic damages produced by Santa, someone could speculate on it?

[Assistant]
Despite the long and proud tradition of Santa's elves working tirelessly to make toys for all the good little boys and girls of the world, hardly *any* of the toys are manufactured at the North Pole facility anymore.  It's been that way for several decades now.

The toy manufacturers and retailers of the world get significant tax breaks by donating some of their inventory to Santa, and it's pretty good for their public relations.  The manufacturing parts of Santa's operation are currently more focused on building and maintaining high-magitek sleighs that can haul such large amounts of gifts without sacrificing speed or safety.


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

[User] ELI5: What's the difference between intensive care medicine and emergency medicine?

[Assistant]
Emergency care is about stabilising people so they can be treated for the problem whether that's a cast on a broken leg or emergency surgery following a car accident. They are about treating what is found and immediate life saving or harm reduction and moving people on either to further care or home one treatment competed

Intensive care is very high dependency care usually 1to1 nursing for someone who is very seriously ill or in a condition that needs constant monitoring. So following complicated surgery or sepsis or ventilation required for example. People can be on itu/icu for long term treatment or just a few hours during surgery recovery. They are likely discharged to a normal ward or high dependancy ward for further recovery. (high dependancy may be 1to 3 nursing for those who need more care than a ward but not as much as icu)


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

[User] ELI5:What does Aspirin do to us?

[Assistant]
So aspirin has a couple of therapeutic effects. It is known as a salicylate (this is important later on) and a NSAID, non steroidal anti-inflammatory drug. To start it is an antipyretic, also known as a fever reducer, much like Tylenol.

It is also an anti inflammatory, aka stops swelling, and an analgesic, aka stops pain.

Its most common use though is for anti platelet which means that it lowers the platelet amount in your body in order to prevent clots, which can wreak havoc if they get to the lungs or brain. In the lungs it causes a pulmonary embolism and in the brain it causes a stroke. It also is used to prevent heart attacks due to these properties. If platelets are higher than 450,000 per microliter of blood, there is an increased risk for these clots. Aspirin will lower the function of platelets  sticking together and prevent coagulation.

However, you cannot give aspirin to a child as it can cause Reye syndrome, which is deadly. If youd like me to go into depth about the other three effects let me know, but there are much better options for those, including for children.

Edit: misspoke, evidence of comment down below. Sorry guys, doing multiple things at once!


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

[User] ELI5: What causes flu season? Where does it go during the summer months and how does it come back?

[Assistant] It is not so much that it is a "season, but rather the conditions that occur. The easiest way to spread the flu is to be is close contact with people. During the colder winter months, people stay inside more often and that causes exposure to more people that might have the flu. Compared to summer where people are outside more often and although they may come into contact with someone who has the flu, they are not constantly exposed to multiple people who have it.


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

[User]
Bergson and neuroscience

In *Matter and Memory* Henri Bergson seems to propose that human beings unconsciously retain 100% of our experiences in memory and that a failure to remember a particular \`something\` is more of a mechanical/physiological error on the part of the brain specifically than a non-existence of the memory. I will say that I am not an experienced scholar in this area of study so I may be misunderstanding his position. I would like to know whether there is any empirical evidence in modern neuroscience to support his claim? I understand that in many of Bergson\`s ideas he gives very little reasoning or explanation in the first place but I do feel as though there is some truth to the idea and have had similar thoughts about memories that seems to appear out of nowhere.

[Assistant] That's not really what Bergson is arguing. Bergson is a dualist  (though a very unique one); what he wants to show is how pure experience surpasses the brain so to speak, and that it's the brain that funnels or filters this pure experience into the experience that corresponds with successful bodily/practical action in the world. He has a very functionalist account of how the mind works *at the level of cerebral activity*: the brain isn't a box of memories, but a collection of operations or a set of rules to use pure experience (or pure past time) in a way that allows us to function in the world.


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

[User]
How do they make decaffeinated coffee?

I would really like to know.

[Assistant]
You know the gas, carbon dioxide (CO2)? If you squeeze it really tightly--put it under very high pressure--it actually behaves kind of like a liquid. Like a liquid, it can dissolve things, like water can dissolve salt. Imagine you have a toy that's covered in salt that you want to get rid of. A simple way of getting rid of the salt would be to toss the toy in some water. The salt dissolves, but the toy is intact, and you end up with a salt-free toy.

Coffee decaffeination works in a similar way, except instead of water, this liquid-like CO2 is used. This CO2 can dissolve caffeine, but not other things in a coffee bean. So if you run this special CO2 over a batch of coffee beans, you'll take out all of the caffeine, leaving you with caffeine-free coffee beans. And, as a special bonus: you also get a bunch of pure caffeine dissolved in this special CO2, which you can sell to companies that put caffeine in their products! And getting the caffeine out is really easy. In the salty toy example, if you wanted to get your salt back, you would have to evaporate the water that the salt was dissolved in. That can take a long time. But with the special CO2, you simply un-squeeze it, and then it becomes normal gaseous CO2, leaving you with your caffeine.


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

[User]
How do we know how big neutron stars are?

I've heard they are around 20 km in diameter. But how on earth do we know this when they are so far away? Is it just a guess based on their mass?

[Assistant]
We don't.

It's a big open question right now.

We know how massive they are, we can get that from observations of orbiting binaries.

To get their radius, we have to interpret other observations, or use theory. For example, we know what neutron stars are made of, so we can predict how 'squishy' the neutrons and protons in their core are. Knowing this, we can calculate the radius of a neutron star of a given mass. But we don't know *exactly* what they're made of, and we don't know *exactly* how squishy that stuff is. So we're modeling them. At present, we know they're about 11-13 km in radius or so, but hopefully we'll know it to within 10% once the NICER mission gives us some results.


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

[User]
[Final Fantasy X] Does the water have anomalous properties or are some people just really, really good at holding their breath? ...Gills?

In the blitzball spheres, in the sea... Everyone seems to just jump in and stay underwater indefinitely, even through intense activity and combat.

[Assistant] The water contains pyreflys, which work with the machina that make the water float in a sphere. They help support the players while they play, although it also does require training and impressive stamina.


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

[User] [MegaMind] MegaMind is serving 85 life sentences, does this mean that he has killed at least 85 people?

[Assistant]
US justice system sometimes has brainfarts by combining the years from several convictions, so there were cases where people got sentenced to six hundred years in jail or some shit like this.

Considering that MegaMind is very adept at causing mayhem, it's likely some judge had enough of his shit and just counted every violation for max time and summed it up together.


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

[User]
Why do you sometimes temporarily lose your hearing when yawning?

Edit: more of an impairment that a complete loss of hearing, I can still hear its just muffled and quite.

[Assistant]
When you yawn you end up flexing your tensor tympani muscle, a muscle in the ear that is used to dampen loud sounds like when you chew food.

Some people can flex this muscle independently of yawning. One way you might be able to do so is by shutting your eyes very tightly and kind of scrunching your face as you do so. It should sound like a low rumbling sound.


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

[User]
[X-Men] Why are so many mutants blue?

As opposed to other possible colors?

[Assistant] Maybe the genetic markers for the X-gene predispose to blue coloration in some kind of link, like red hair and freckles or needing more paint medicine, or blue eyes and higher alcohol tolerance. Or, y'know, lots of people have relation to Apokalypse.