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

[User]
How does AI work if computers can only do what they are programmed to do?

I don't really understand AI. How can a computer or something like it learn when the only thing they can do is what they are programmed to do? Wouldn't all the learning be expected by the person that programmed it? Can the AI really do thinking?

[Assistant]
The cutting edge of specific AI now is neural networks and machine learning. Systems like this are trained with examples.

The recent DeepMind Go AI that you might've heard about works like this. It learned how to play Go by analyzing millions of games, then played against itself millions of times and analyzed those games, while modifying the AI each time and keeping the version that wins.

This is called machine learning. It uses statistics and sets of inputs and outputs to predict new output for a given input. The creators of the Go AI don't know how it chooses a specific move.


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

[User]
(Batman) Why can't the world's greatest detective figure out the jokers identity?

Surely it can't be that hard? Unless the Joker is smarter than Batman which I doubt.

[Assistant] Why bother? The Joker doesn't have a consistent alter ego the way Bats does. It's not like he spends his weekends as the mild-mannered John Jokerberg; he's Joker 24-7. So even if Batman did go to the trouble of finding out the name of the person Joker used to be, that's all it would be... A name. There's nothing to learn from it. Joker is Joker.


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

[User]
Do ears have depth perception?

I know that having two eyes enables us to be able to perceive depth. Do our ears do the same thing?

[Assistant]
No, they cannot. You can only hear the direction where the sound is coming from (and this in all 3 dimensions!). This is because the sound will hit your ears at different times (so you can tell if it is from left or right), and it will be forwarded a bit different dependent on the direction it hits your auricle (you can then tell if it is from behind/front and up/down).

Also: you only have the depth perception of your eyes because they overlap and each one has a slightly different picture, and this picture is made of linear photons, while sound is brought to you by a wave that gets around corners.

*btw, this is not psychology at all. This is biology/medicine and/or neuroscience*


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

[User]
Why do young children cry at bedtime?

This isn't a parenting question.  Is there a scientific explanation for why toddlers and young kids cry when they are put to bed?  Anything evolutionary?  Do any other young animals cry before going to sleep?

I thought about this question because my wife just put to be a 17 month old foster child and he immediately started crying as soon as he was placed in the crib.

[Assistant] Remember that the idea of having babies and small children sleep in a separate room - much less a separate bed - from his or her parents is an incredibly recent invention in terms of human evolution, and it's not a universal invention either. Babies didn't evolve to cry when they're being put to bed; they evolved to cry when they're separated from their parents.


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

[User] ELI5: Why when upside-down does blood all go to our head, but when standing up blood flow is normal?

[Assistant] The normal state of our bodies involves having to pump blood "towards our head" against gravity to reach our brains. This is different from the idea that we pump blood "up". When you are turned upside down, your body is still doing the work of pumping the blood "towards your head" but now it is also having gravity pull the blood towards your head too instead of away from it.


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

[User]
ELI5: Why does getting a massage make you feel good?

I always wonder the mechanism of how rubbing muscle can make one feel good. It might be somthing about chemical reaction related to blood circulation and oxigen supplyment. How and what part of our body contribute to feel it?

[Assistant]
A few reasons. Firstly because massage relaxes the muscles, reduces discomfort/ pain (by pain gating mechanism through the spine), promotes blood flow and helps to  strengthen the muscles and joints. It's beneficial effects also include endorphin release in the brain, which is similar to morphine (= relaxation, well being, bliss)

Secondly, massage has evolutionary  roots. Grooming is part of our ape + developmental  past and it clearly *still* helps with personal/ group  bonding and the additional  psychological benefits.


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

[User]
question on the movie interstellar (which I am told is fairly scientifically accurate), if time on the water planet moves so slowly, what would someone on the shuttle observe with a really good telescope?

So if I recall, massive gravitational forces slow time, and in the movie, they depicted 1 astronaut remaining on a ship out of range, but within view (perhaps with a super large telescope)

So theoretically, if this is remotely scientificly accurate, what would the person on the space shuttle see when they looked down at the planet?  would they see a person moving at super slow speeds?

[Assistant]
Things on the planet would appear to be moving extremely slowly. However, the rate at which light escapes the planet is also hugely dilated, and each photon is stretched out (redshifted) as it moves through the extreme gravitational field.

The redshift factor is the same as the time dilation faction, for a simple non-rotating black hole. In the movie, one hour on the planet is seven years for a distant observer, which comes out to a factor of 60,000. So you would be receiving photons from the planet 60,000 times more slowly, making it very very dim.

The light would also be so redshifted that it would not be visible. The visible light would be stretched down to low-energy microwaves - almost radio waves. X-ray radiation would be redshifted down to visible light, so you could see that, but if there's that many x-rays coming out of the planet, it's not going to be somewhere with an atmosphere and an ocean.

So yeah, you could see people moving slowly, but you'd need special equipment to see anything at all really.


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

[User]
[Halo] What exactly happened to Harvest after the Human victory there?

Was the planet held in Human hands for the entire war? Was there just a quick assault by Covenant forces and never brought up again? It was a pretty costly victory and I can't find anything about it Post Second Harvest conflict.

[Assistant] Harvest was glassed during the First Harvest Conflict, and whatever was left of it was torn up during the Second. While there is no reason to believe that humanity ever lost control of the planet again, there was also no reason for the Covenant to attack it again considering how much of it's worth had been destroyed. Many glassed planets were terraformed and re-settled after the war, so its possible Harvest has been recolonized.


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

[User] [Batman] Did Bruce and Alfred set the Batcave up all by themselves, or did they hire contractors who just thought they were doing some basement work for Mr. Wayne?

[Assistant]
A bit of all of the above but also the Caves under the Manor were used at different times by different Waynes for illegal at the time activities.

The caves were used as a hiding place for American Troops during the War of Independence,  part of the Underground Railroad in the run up to the Civil War and were used to house fugitive slaves and abolitionists, and during the Prohibition to store alcohol.

I cant swear to it, but i think the caves could also have been prepped as a survival bunker during the Cold War.

Undoubtedly any mundane construction crew would be told  that the complex was being refurbished for historical research and/or to make a safe room/survival bunker.


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

[User]
[Jumanji] Is Van Pelt a persistent threat in Jumanji, or was he created specifically for Alan Parrish?

Van Pelt quite obviously resembles Alan's father, and he's clearly another creation of the game, much like the plants and animals - but is he a persistent feature of the game that's likely to come out due to a roll of the dice?

If I were playing the game, would Van Pelt resemble my father, or would the game create a different human antagonist for me to face?

[Assistant]
The rhyme that introduced him was:
>A hunter from the darkest wild
Makes you feel like a child.

Van Pelt resembles Alan's father because that's who Alan feared the most as a child (and brings those feelings back).
If you got along well with your father as a child Van Pelt would probably resemble someone you feared as a child, like a creepy uncle or a scary gym teacher.


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

[User]
Introductory books for understanding Kant, Hegel, Marx, Lacan, Zizek, Semiotics, and post-structuralism?

Hi everyone, I have a (very) basic understanding of all of the above, however it is very unstructured and based on bits from here and there. What are your recommendations on books that introduce the above, preferably in an organised sistematic manner? Books that would pave a way for further development by helping to set up a foundation.

Of course recommendations of books, courses, podcasts that link two or more of them are very welcomed.

[Assistant]
Some general recommendations:

*Kant* by Guyer

*Hegel* by Beiser

*The Philosophy of Marx* by Balibar

*The Lacanian Subject* by Bruce Fink

*How to Read Lacan* by Zizek

*Critical Semiotics* by Genosko

*French Philosophy in the Twentieth Century* by Gutting.

One could probably list hundreds of more books, but as a start, these will serve you well.


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

[User] [Star Wars] Did Obi-Wan pick Tatooine because Vader would avoid the planet and connections to his past, or because he wanted Luke to have what Anakin didn't; a stable family and upbringing?

[Assistant]
It's full of sand. Anakin's natural enemy.

Jokes aside, it's likely both, since Tatooine allows him to hit both wompas with one stone, since Tatooine for Vader is full of attachments he'd rather leave behind - and by this time he likely did, and won't give the planet a second thought, and because Larses are the only living family Luke still has that can raise him like a normal person. And the planet is a huge desert, it's not hard for Obi-Wan himself to get lost there and keep an eye on Luke.


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

[User]
[Marvel Comics] Why are Mutants treated differently from other superpowered humans?

Most mutants don't show their powers until puberty, the children aren't recognized as having "birth defects." A fourteen--year-old suddenly developing powers because of their genes is no different from a sixteen-year-old suddenly developing powers because someone let the spider out.

Why are people protesting mutants but they don't question other people jacked up on super-serum or radioactive blood? Kitty Pride is an abomination but the Human Torch is totally okay?

How would anyone know how superpowered people got their special abilities anyway? How can anyone tell that Colossus was born with mutant genes, but the Hulk got blasted with gamma rays?

[Assistant]
Because people aren't afraid of humanity being replaced by the Human Torch or the Incredible Hulk.

A lit of mutants run around claiming they are the next step on the evolutionary ladder and will take homo sapiens place.

Makes people nervous.


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

[User]
[MCU] Did half of the gut bacteria and the mites on skin and eyelashes get dusted in The Snap? Do half of them stay behind and just get dumped on the floor? What about tapeworms?

I guess the stones figured it all out, but half of all life is half of all life.

[Assistant]
Well with bacteria, viruses etc living on organisms that were snapped then presumably they went with the host.

I also think there might be a caveat, insofar as Thanos (and later, Banner and Stark) had to concentrate on what exactly was getting snapped away / back, so presumably it was a section of the population that Thanos picked. Otherwise youd be screwed if half of all of the plant life vanished from every planetary ecosystem.


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

[User]
[General fantasy/rogue-like] Why is there a merchant in an incredibly dangerous dungeon?

A dungeon, teeming with animated skeletons, rabid monsters, and demon spawns, is somehow a good place to set up shop?

Yeah maybe they can take advantage of stupidly brave adventurers that only make it a few floors, but there's a merchant even at the dungeon's deepest floors.

And no matter where the shop is, it's almost always the same merchant!

What kind of powers does this merchant have, and why do they only use it to sucker off a handful of adventurers?

[Assistant]
Dungeons are full of treasure. That foolhardy adventurer is busy killing monsters and picking all that treasure up. The merchant in the dungeon gets first pick of the stuff the adventurer wants to trade or sell. Plus, the adventurer is flush with cash and probably desperate for supplies.

As for how they get in there: they sneak well. Adventurers are loud and looking for a fight. The merchant is patient and looking for a quiet corner to hide out in. Monsters aren't immune to bribes or distracting shiney things - which the merchant can afford to give away because the adventurer will bring them right back.


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

[User]
Not a professor but a graduate student. I would like to write a recommendation letter for my thesis advisor as she is an awesome mentor who really cares about students and is an inspiring scientist.

Im a PhD candidate in biology and in a research- focused university. I hope to seek some advice regarding  writing recommendation letter for my thesis advisor to the Vice Dean in charge of faculty. My advisor ( relatively young PI) is an exemplary mentor who has inspired me in many ways in terms of scientific thinking and she truly cares a lot about students progress/and gives us both the space and support to develop our scientific minds. Therefore,
I would like to write a recommendation letter for her in hope that it will be beneficial for her tenure consideration.

My hesitation is that: how effective will this letter be in aiding her to get tenure? Or will it on the contrary, be something against her(?)- I am not sure how common is this practice of students writing recommendation letters for their advisors are in academia.

[Assistant]
The best thing to do is ask the professor whether there is any way you can help her compile materials for her tenure application. While that conversation is taking place, ask whether there is any room for a student to write about how much she has helped as a mentor.

The guidelines are different at every university, but they are generally organized around teaching, research, and service. The mentorship/advising of a PhD student can often be bent and shaped to be included in any of the three sections. (There will always be a set place for it, but if she needs it to help support a weaker area of her application.) So, in summary, the best thing that you can do is make the offer directly to her and offer to do whatever she needs to help her case for tenure. If she doesnt need the help, shell be happy that you asked because shell know personally that shes doing a good job in that part of her job. If she does need help, shell be glad to have an ally in presenting her case.


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

[User]
Why trench run the Death Star?

And not just fly directly at it, use a guided missile or even drop a droid into there?

[Assistant]
For starters, the trench is more protected from all of the turrets mounted on the Death Star.  Yes, there are turrets in the trench, but there are more above the trench.  While in the trench, the angle of attack is such that the turrets above the trench cannot hit an X-wing.

Secondly, remember the movie 300, where the Greeks channeled all of the Persians into one little area to even the odds a bit?  While in the trench, you're not going to have to deal with 30 tie fighters all at once.  At most you'd have to worry about 2 or 3, and they'd be getting in each other's way.

Finally, the trench was a direct path to the exhaust port.  It's like driving on the freeway vs driving over a bunch of fields.  On the freeway, you don't have to pay attention because the road gets you where you want to go.  Driving on the fields, and you could easily start driving in circles without even realizing it.


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

[User] [ELI5] Why do we sometimes have to gag when we only see disgusting things?

[Assistant]
Because you have an evolutionary incentive to do so.

Your ancient ancestors had an omnivorous diet of fruits, nuts and meat where they could find it. Imagine you see that the inside of a carcass you're eating is rotten and full of maggots. Gagging is your brain telling you to eject the contents of your stomach to avoid poisoning yourself.

This is also the reason why you feel the need to vommit when someone else does. You may have ingested the same poison. After all, if that ape is near you then they're probably in your group. And you're probably eating the same thing they are. Therefore better safe than sorry.

Sure...you may lose the contents of your stomach, but it's better than death.


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

[User]
CMV: Motorcycles need much stricter sound restrictions.

Im in the US and many motorcycles are ear ringing loud with little to no enforcement. But Ive also been to many cities in Europe (especially Greece) where there are a lot more motorcycles on the roads. Im sure this is the same in South America, Africa and Asia. The sheer number of loud unrestricted motorcycles and their sounds reflecting off of the buildings really pollutes the city with noise. Its hard to get a piece of mind for just a moment with all of the noise.

I think there should be much stricter and widely enforced sound restrictions for motorcycles to help clean up sound pollution throughout the world.

[Assistant]
The US as you have already said pretty much has restrictions, they aren't enforced pretty much.

Most states that I've ridden in have 70 decibel limit on exhaust noise.

But as for the rest... are you saying we need worldwide rules on this for Europe and the other places you mentioned?


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

[User]
Is it better in the long term for a car to be "warmed up" in cold weather before using it?

If not, at what temperature does warming it up become necessary? This question comes from a friend in Michigan.

[Assistant]
Michigan native, automotive engineer (mechanical) and general gearhead here.  To expand on what botanist said:

Start the engine and give it 30 seconds of running to build oil pressure.  It will build faster than that, but it's fine.  If your car is covered in snow/ice, take the 5 minutes to get it all off.

Drive away, but be gentle on the gas pedal.  Try not to rev beyond 2,000rpm until the temperature gauge is in the 'normal' range.  This means just up off of 'cold'.

After that, drive normally.

If you idle for extended periods, you're getting 0mpg.  Idling doesn't generate as much heat as driving down the road, so your car warms faster while underway.  Also, modern cars have EGR (exhaust gas recirculation) for emissions purposes.  Idling an EGR-equipped engine extensively will foul up your oil with combustion byproducts and acidify the oil prematurely.  So really there's no reason to leave your car idling longer than 5 minutes or so.


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

[User] What is the science behind 2 cans transmitting sound to each other via string?

[Assistant]
You poke a hole in the bottom of each can, pull a string through, tie a knot to hold the string in place and pull the string taut.

What happens next is nearly exactly the same as how sound transmission through air works:

- You speak into the can. Your vocal cords create longitudinal waves (of sound) in the air.
- The sound waves hit the bottom of the can, which vibrates slightly. In this sense, the bottom of the can acts like the diaphragm of a microphone.
- The vibration from the bottom of the can once again creates a longitudinal wave through the string. This wave moves through the string at the *string's* speed of sound.
- The wave from the string transfers to the bottom of the other can, which vibrates much like a speaker cone.
- The vibrating can bottom creates pressure/longitudinal waves in the air, and that vibrates your ear drum, and that's what you hear.


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

[User] ELI5:why are there so many kid with peanut allergies this generation? And why does it seem like only an American problem?

[Assistant]
Your immune system acts like a police force for your body to protect it from foreign particles.

When your body is exposed to bacteria, viruses, or other harmful foreign matter, your internal police force is busy making sure everything is safe.

But what if you don't get much exposure? Your immune system is always active so they start looking for other ways of "working" in order to justify their existence. They start triggering responses from non-harmful things such as pollen or parts of the food we eat.

This is the basis of the "hygiene hypothesis" for the rise in allergies in the recent decades. Because technology allows us to be more and more clean than our previous generations and with fewer children are playing outside, the childrens' immune systems don't experience enough bad things to occupy them. So the immune system decide to target non-harmful or good things to attack.


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

[User] ELI5: If the universe is expanding, aren't new stars being born all the time? And I guess they would be even if it wasn't, so why is it said that the universe will be completely dead one day?

[Assistant]
The idea is that, while the universe is expanding in size, the amount of matter and energy in it is finite. That whole, can't be created or destroyed thing.

What happens when you have a set amount of something in a container that's getting bigger?

Eventually the universe will be so massive and stretched out that there'll be mere ones of atoms per cubic kilometer.

Not much of a universe at that point, is it? Certainly not one full of stars and planets and junk.


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

[User]
[Matrix Series] If the self in the Matrix is a "residual self image" are there any "coppertops" that are not the same gender in the matrix as in the pod?

I was just giving this some thought and wondered if that was possible.  Think that you're female and then be awoken to find out the dude in the pod was a dude...

[Assistant]
Yes. Or "yes" to a certain degree, more relative to sex than to gender. A person may be born a man in the Matrix, but later self-identifies as a woman. People in the matrix would call the person "transgender". In reality, the person's body in the pod is female. The physical representation of the body glitched and failed to properly reflect the actual sex of the baby in the pod at birth.

[META] This is canon. The character Switch (the woman with the white hair in the original film) is canonically a transwoman, which is also where she got her original hacker name. She was born male, identified as a transwoman, was saved from the Matrix, and when she jacked back into the Matrix, she had a new biologically female RSI. The Wachowskis were told by the studio that they couldn't use the subplot, even in passing mention.[/META]


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

[User]
ELI5: Why can't I get internet without an ISP or cable company?

I just want to know what they have that I don't, and if I can get it.

[Assistant]
Well, not to make it too simple, but they have the connection to the Internet.

Same reason you need to go to a gas station to get gas. You can't go to the refinery and get it; they are simply not going to sell you that small an amount of gas. The refineries only sell to distributors, who in turn only sell to gas stations.

ISPs buy connectivity in bulk from backbone providers (Level3 for example). Level3 couldn't care less about your measly 10 megabit connection; they deal in gigabits and terabits.


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

[User]
[Star Wars EU] How much service did the Victory class and Imperator class star destroyers see during the clone wars conflict?

The victory class star destroyer was introduced around 20 BBY and first saw combat under Captain Doddannas Victroy fleet (sent against the Seperatist Bulwark fleets).
Meanwhile the Imperator class destroyer was introduced during 19BBY.

Both ships apparently were actually used by the Republic along with the Venator, acclamator, and Tector class destroyers (the Tector saw barely any use after its field test proved disastrous).

Though how much service/use exactly did the Victory and Imperator see in the clone wars conflict?

[Assistant]
While it is noted that the so-called "Victory Fleet" was put into combat against the Seperatist units threatening Coruscant, it is also noted that "majority of the initial commission group" was not deployed until the Clone Wars ended. It seems very likely that the existing Victories were held in reserve to continue defending Coruscant Sector until the war's end; in this role, we know they participated in the final defense of Coruscant.

We actually know less about the Imperator/Imperial-class' record of general service. Some were in service with "several Republic task forces", and arguably the fact that both Venator- and Victory-class' production was still being slowed to make way for Imperators suggests that the type had enough service to prove itself in combat as a more valuable vessel. Actual details, however, are scarce.


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

[User]
[Watchmen] Why was U.S. unsure of whether or not Dr.Manhattan could stop all the nukes once they had launched ?

Was it a question of power or did they think that he just did not care enough to do so. Would love to hear your thoughts.

[Assistant] I believe it's most likely the latter - since Dr. Manhattan already shown that his powers have essentially no limits, and he's closest thing to a God that setting has, it's almost always the matter of him caring enough to do something, opposed to not being able to. And he already was showing a lot of detachment from humanity, so...


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

[User]
[The Fast and the Furious] Inconsistencies with Letty's "murder".

So at the end of *The Fast and The Furious 1*, Letty flees Los Angeles. She ends up in the Dominican Republic and reunites with Dom.

In *Fast and Furious 4*, after Dom goes to Rio de Janeiro, Letty returns to Los Angeles. She contacts Brian and agrees to infiltrate Arturo Braga's cartel in exchange for Dom getting a full pardon for all his crimes; however, Braga is aware she's a mole and has Fenix Calderon murder her in a way that looks like a car accident.

Then in *Fast and Furious 6*, it turns out she's still alive but has retrograde amnesia. Rather than shooting Letty in the head, Fenix shot her car to blow it up; Letty was thrown from the road by the explosion. Owen Shaw states that he found her in a hospital, where he recruited her; it's implied that he originally intended to kill her in hospital, and recruited her because she had no memory. Letty doesn't have any contradictory memories, which indicates Shaw wasn't lying about that part.

Two questions about this...

1: Letty's funeral was well-attended. Who is in her grave?

2: If Braga wanted Letty dead, why didn't Fenix finish the job?

[Assistant]
There wasn't a body  Owen faked her death when he recruited hee.

Fenix messed up. He assumed that she died when the car exploded and didn't bother to check. That's why Owen went to finish her off and not fenix.


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

[User] Do peoples eyes really "change colour"?

[Assistant]
Color is determined by both physical properties of an object and the properties of light around it.

The pigments in our eyes which determine what wavelengths are absorbed and reflected do not change.

However, the color can change based on the type of lighting (florescent, incandescent, candle, sunlight, etc) and the dominant colors in the immediate environment, which can include clothing.  Both of those things change the distribution of wavelengths that hit the eye (and everything else) and so also change the distribution of what is reflected back (which is what we think of as 'color').

Additionally, in bright light, where those effects are minor, putting on a very bright green shirt, for example, might make the person's eyes look less green in comparison.  This, though, is purely a perception issue of humans, and so the color would still be the same if measured by say, a camera, which is not the case above.


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

[User] [Indiana Jones Films] Shouldn't Indiana Jones be in jail for life on multiple murder charges instead of teaching in an American university part time?

[Assistant] Most of his kills are done in self defense and overseas to boot. There aren't exactly a lot of cops around to arrest him while he's tossing Nazis into propellers. Anyway, who's going to charge him, and who's going to testify, Nazi Villain #3?


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

[User]
ELI5: What's the difference between murder and culpable homicide?

I've been asked about this on Twitter, by someone who is struggling to understand how Oscar Prestorious can be not guilty of murder, when he knowingly fired four shots into a bathroom where he believed an intruder to be.  She says, even if he thought it was an intruder, the mere fact that he shot with the intention to kill another human being makes it murder.  Can somebody please explain the legal differences and why those differences are an important aspect of a fair justice system?

I'm an anthropologist, not a lawyer, so even though I (mostly) understand the differences, I can't break it down and explain it in a way that would be useful at all.

[Assistant]
Pistorius was charged with premeditated murder, which implies that he had planned on killing Steenkamp at some time in the future, meaning if he hadn't killed her that night, he would have killed her some other time. In the eyes of the judge, the prosecutors didn't prove that he had planned out her murder, so she ruled in Pistorius' favor.

He was found guilty of culpable homicide, which implies he may not have meant to kill her. Pistorius claims he thought she was a home invader. The judge found him guilty of culpable homicide because he was negligent: he didn't call the police, he didn't give whoever he thought was inside the bathroom any opportunity to escape, he simply fired through the door, which killed her.

EDIT: Spelling.


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

[User]
ELI5: Is a human virgin birth scientifically possible?

I am not asking this to start a huge debate on religion.  I am simply wondering if a virgin birth is a scientifically feasible concept.  Obviously during the Bronze Age artificial insemination did not exist yet.  I'm curious if there is any other way a woman could get pregnant without having intercourse.

[Assistant] If a woman is a virgin until a penis enters her vagina, then yes, virgin births are possible. If a man were to ejaculate on her, it's possible that sperm cells could swim up the vaginal canal and make her pregnant.


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

[User]
[Marvel] How is Tony Stark able to fly without hurting his neck? He flies parallel to the ground but with his head facing forward, and I imagine it would be extremely uncomfortable long-term.

Just try laying flat on your stomach but still facing forward towards the wall in front of you, it's uncomfortable. If he was flying for long periods of time I imagine it would seriously put a crick in his neck.

[Assistant] Tony Stark most likely takes muscle relaxers for his neck and other muscles that would tense up from being immobile for long periods of time. On top of that he now has a stabilized form of extremis constantly healing him.


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

[User] ELI5: Why is it okay to eat blue cheese, but not other things that are moldy?

[Assistant]
Different species of mold have make different byproducts as they grow, and not all of them are harmful. Through experience we know some that are safe, like those used in making cheese. (Yeast is also a fungus, but not a mold, and is used for baking and brewing.) When food around the house gets moldy from whatever spores were in the air, it's a bad bet: there's a big risk that whatever mold it is either is generally poisonous or might produce something you're allergic to.

This why cleanliness is actually very important when working with mold. Get the wrong kind of fungus in your product and it will ruin the whole batch.


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

[User] Why is it that certain elements are common in asteroids, e.g. iridium, but rare on Earth?

[Assistant] in the case of iridium it is really really dense and a lot of it descended deep into the earth when the earth was young, so much of our iridium is closer to the core than on the crust. the same is probably true for any element that is really dense.


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

[User] Why can't your immune get rid of bacterial STDs like syphilis etc?

[Assistant]
It varies depending on the pathogen. When it comes to syphilis in particular, the outer cell membrane has unusually few of its own antigens (proteins) in it, which makes it harder for the immune system to detect it. It can also vary its antigens by gene conversion.

That said, the immune system can combat syphilis. It's just usually not enough to clear the infection. When the bacteria lyse (split open), their internal components are easily recognized by the immune system - their camouflage is only skin-deep. This can actually be a problem when treating syphilis, as a bunch of bacteria dying at the same time can make the immune system overreact to the suddenly abundant foreign antigens etc.

STDs aren't necessarily anything special in terms of ability to evade the immune system. Lots of pathogens have found ways to do that. Mycobacterium tuberculosis, for example, has a coating that allows it to survive inside the phagolysosome of macrophages; the substances the macrophage pumps into the phagolysosome would kill almost any other bacterium.


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

[User] [Marvel/DC] Are there any universe/multiverse ending disasters that don't involve Earth?

[Assistant] The Annihilation Wave dealt a lot of destruction to a good chunk of the star-faring civilizations of the Marvel Universe (the Kree, Skrulls, Shi'ar, etc.), and while a number of earthborn heroes were involved, Earth itself played no part in the event.


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

[User]
[Harry Potter] Are new spells actually created, or are they "discovered"?

There's a wide variety of spells in the HP universe, ranging from lethal in battle  to practical in everyday life. So there's obviously been a lot of learning how to harness Magic. So is there a set amount of spells, or can witches and wizards create them infinitely?

As an example, when Snape "creates" the Sectumsempra spell, was it actually created as a new way to harness magic, or did he just discover an existing way that wasn't previously known?

[Assistant]
Probably created. Otherwise, the similarity between the spell's function and the meaning of its latinesque incantation would either be a huge coincidence, imply that the use of magic predated language (which wouldn't make sense, since Latin didn't originate in different places all over the world), or imply that some giver/source of magic also spoke "Latin".

Perhaps it's a combination: there is a preset collection of possible spells, and the spell creator creates a way to access that spell he suspects exists.


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

[User] ELI5: Why don't humans dissolve in either polar or nonpolar solvents? I mean, I get why water doesn't dissolve me, but why doesn't gasoline?

[Assistant] You can certainly strip the protective layer of skin oils from your skin with detergents and solvents, but our skin forms a very strong barrier, composed of many layers. The top layer is dead skin cells made primarily of keratin and other proteins. You would need something that denatures or destroys proteins, such as extreme heat, acid, bases, etc.


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

[User]
ELI5: Why are there so many violent radical Islamic peoples compared to radical Christian and Jewish peoples?

Title worded funny...

[Assistant]
It's the time we live in. War and poverty in the location where that specific demographic is located.

If you look back in time, to the middle/dark age, the roles were reversed. Militant extremist christians doing much of what extremists are doing today, but in Europe.
The middle east at that time experienced a time of enlightenment with emphasis on philosophy, religion and math. Mordern algebra for instance has it's roots in the middle east of that time.


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

[User]
Is there any way to improve intelligence or are we stuck with what we have?

Barring implants, neural "cyborg-ification", etc.

[Assistant]
Richard Feynmann claimed that he wasn't exceptionally intelligent, but that he focused all his energies on one thing. Of course he _was_ exceptionally intelligent, but he makes a good point.

I think one way to improve your intelligence is to actually try to understand things in a very fundamental way. Rather than just accepting the kind of trite explanations that most people accept - for instance, that electricity is electrons moving along a wire - try to really find out and understand what is actually happening, and you'll begin to find that the world is very different from what you have been taught and you'll be able to make more intelligent observations about it.


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

[User]
[ELI5] why do stoves use meaningless scales on their dials?

1-6 & Hi? Low-Hi and Hi+ on the power burner? Watts or rate of fuel flow would provide an easier basis of comparison between stoves and make cooking far more consistent.

[Assistant] The arbitrary scales are easy to implement and easy to understand. Using a "real" unit like watts or fuel flow would take extra instrumentation and careful calibration and, even then, would not give you consistent cooking because you care about how much energy gets transferred to the food, which is extremely strongly influenced by the shape of the burner, the shape of the flames, and the cooking vessel.


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

[User] ELI5: Why do joints make a "Cracking" noise for certain activities such as walking up stairs, but have no actual pain associated with them?

[Assistant]
The generally accepted reason is the diffusion of (and the resulting collapse of) gaseous bubbles in the fluids between your bones/cartilage.

The debate is still out on whether its the bubble forming that makes the sound or the bubble collapsing that makes the sound.

However youll notice you can only crack joints that you havent moved in a while, which allows the gasses to diffuse. Then you can pull the joint apart creating a void which is promptly filled by the gasses diffused in the fluids surrounding the joint as the pressure drops in that area. Eventually pressure returns to normal and the bubble collapses.

Again, generally its accepted that the collapse of the bubble is the cause of the sound but the debate is still out on that.


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

[User] ELI5: How come sometimes when you take a drink, it causes extreme pain and discomfort as it goes down?

[Assistant]
The bolas you've formed to swallow is too large and stretching out the muscles of your esophagus as it travels down your throat.

Edit to add:

The throat is a tube with muscles that can squeeze or relax but no muscles that open the throat wider. So what happens is each section of the throat widens because the section above it squeezes a football shaped pocket of food down like getting the last glob of toothpaste out by squeezing the tube from the very bottom and working it out. The tongue is what kicks off the process. If the ball of food in your mouth is too large, the ball working its way down stretches the muscles as it passes through the tube.


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

[User]
ELI5: why is 0! equal to 1?

0 factorial is equal to one and i was just wondering the math/logic behind this since factorial means multiplying by all whole positive integers before the number and 0 has no whole positive integers before it.

[Assistant]
We can define the factorial function recursively as:

For all positive integers n, n! = n * (n-1)!.

This then implies that n = n! / (n-1)!.  However, this leads to 1 = 1! / 0!.  Since we'd like for this identity to apply to 1 as well, we have to define 0! = 1.


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

[User]
ELI5: If satellite phones provide near universal coverage and have been around for such a long time, why didn't they become the norm?

It worked for pagers, right?

[Assistant]
There are multiple reasons but one of the biggest is the cost to make and receive calls.  From Wikipedia:

>
>
>The cost of making voice calls from a satellite phone varies from around $0.15 to $2 per minute, while calling them from landlines and regular mobile phones is more expensive. Costs for data transmissions (particularly broadband data) can be much higher. Rates from landlines and mobile phones range from $3 to $14 per minute with Iridium, Thuraya[22] and Inmarsat being some of the most expensive networks to call. The receiver of the call pays nothing, unless they are being called via a special reverse-charge service.

>
>
>Making calls between different satellite phone networks is often similarly expensive, with calling rates of up to $15 per minute.

>
>
>Calls from satellite phones to landlines are usually around $0.80 to $1.50 per minute unless special offers are used. Such promotions are usually bound to a particular geographic area where traffic is low.

>
>
>Most satellite phone networks have pre-paid plans, with vouchers ranging from $100 to $5,000.

Most people are not going to pay that much for themselves much less buy satellite phones for their kids.


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

[User] ELI5: why do we automatically change our voices to talk to babys and pet? what causes that?

[Assistant]
It's a form of code switching, and we do it all the time! Not just for babies and animals, but those are more exaggerated examples.

Code switching is when we change our speech according to the situation. Think about the way you'd talk on the phone with customer service vs with a close family member. You're using the same language, and many of the same words, but there are subtle differences. The coolest part to me is one you mentioned - we do this without really thinking about it!


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

[User]
[Pokemon] What's going on with the Kangaskhan baby? Is it even a baby or just an anomaly?

There's no evolution that involves the baby growing up and leaving. In fact, we can breed kangaskhan, and they come out of the egg already with a baby.

Now, this may be game mechanics, but that doesn't add up. They didn't adjust that when they introduced baby pokemon forms in gen 2. Lots of pokemon got baby forms, but no explanation was given for the kangaroo.

What's going on canonically with the baby in its pouch?

[Assistant]
Baby Kangaskhan turn into Cubones if their mother dies.

Cubone -> Marowak -> Kangaskhan

Evidence:

* Cubone skull shape similar to Kangaskhan

* Very similar physiology

* Both overtly Australian (bone-merang, kangaroo)

* In Pokemon Sun and Moon, Cubones' "Call for Help" can summon a Cubone or a Kangaskhan. Most Pokemon only call others from their own evolutionary line.

* The only real reference to "mothers" in original Pokemon were Cubones and Kangaskhan... and the dead Marowak in Lavender Town.

* Kangaskhan likely had an evolutionary line in the original game. If you evolve M', it turns into a Kangaskhan.


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

[User]
[Matrix] Why can agents dodge bullets but not melee attacks?

If an agent is fast enough to dodge a bullet, they should be fast enough to be untouchable. And you can't tell me that red pill people punch faster than bullets, because if they did, they would leave gaping bullet hole wounds the size of their fists.

[Assistant]
They can't always dodge bullets. They need to be able to see it coming.

We also see them dodge and block *many* melee attacks. *Most*, in fact.

And we're seeing them fighting people who are aware enough of the matrix to break the programming a bit. Not to Neo levels, but a bit -- so you're getting fists coming at you *really* fast from *really* close. That's harder than a predefined path of a bullet from a decent distance -- and, again, they still block or dodge the vast majority of them.


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

[User]
[Marvel] Does Daredevil "see" better or worse when it rains?

I was re-watching Season 1 of DD, and during the fight in the rain, I couldn't figure out if DD had an easier or harder time fighting. I can see the argument for both: He can see better because the rain creates sound bouncing off EVERYTHING. Or he can see worse because it's overwhelming or it becomes harder to pinpoint certain objects.

[Assistant] When it rains, he perceives his surroundings with much greater detail but his long range hearing is certainly hampered making it more challenging to detect things further away as the rain drowns out sound over distance.


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

[User]
When is the proper time to use a pointer?

I know you should use them whenever you allocate memory, but is there any other time you would want to use it?

How do you know when to dereference it as well?

Thank you.

[Assistant]
Any time you don't want to make multiple memory allocations for the same data by making copies of the variable ( i.e by pass by value) and passing them around whenever the value changes. By using pointers you pass the address of one memory location (the variable) and update/access the value at that location as needed in your functions, without having to do multiple copying from one variable to an other.

You dereference a pointer whenever you want to access the value held in the memory location that the pointer points to.


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

[User]
ELI5: Why were scientists able to make the fusion H-bomb in the 1950's but have not yet created a working nuclear fusion reactor? What are the major challenges of the second that don't appear in the first?

ELI5: Why were scientists able to make the fusion H-bomb in the 1950's but have not yet created a working nuclear fusion reactor? What are the major challenges of the second that don't appear in the first?

[Assistant]
> What are the major challenges of the second that don't appear in the first?

1. Detonating a 50 kiloton fission first stage to pump a deuterium fusion stage is generally considered to be unfavorable as a method to jumpstart a commercial fusion reactor due to the tendency of this technology to fucking turn the town into a crater.

2. A thermonuclear device only needs to work for a fraction of a second. Sustaining the reaction indefinitely is way harder, though less exciting-looking.


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

[User]
ELI5: Why are air dried towels more absorbent than machine dried towels?

Even accounting for fabric softener, I feel like air dried towels are more absorbent than machine dried.  I could understand if machine dried towels were just more efficiently dried, but wouldn't they then dry out further while sitting in the linen closet? Regardless of the surroundings they were stored in,  line dried seem to be more absorbent. Why is that?

Edit: looks like the consensus is that machine dried towels should be more absorbent than air dried, so there is something wrong with my dryer. Also, white vinegar in the wash cycle to remove fabric softener residue. Thanks for all the info, reddit.

I'm honestly amazed that so many people have such strong opinions about this.

Edit: re fabric softener. When I said I accounted for it when I asked this question,  I just meant that I normally add it to the rinse cycle in the wash, so the towels theoretically have them same amount on them regardless if I then line or machine dry the towels.

Edit: Alright,  Reddit. You win. I've now spent my Saturday washing my towels with vinegar. Instead of fabric softener,  my house smells like pickles. I hope you're happy.

[Assistant]
I know for bath towels specifically, the fabric softeners leave a waxy film on the fibres, making them less absorbent.

I used to work for a cleaning contractor, and our microfibre cloths would become worthless if we forgot, and added a sheet of downy! They would also streak the hell out of mirrors and windows.


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

[User]
What happens to the light/energy that's travelling faster than the universe is expanding?

Energy can't be destroyed, the speed of light is 3,000,000m/s, and the universe is expanding at around 70,000m/s.
Given those facts, light must constantly be travelling past the edge of the universe; what happens to it?

[Assistant]
Where did you get this number? The universe doesn't actually have a speed of expansion! What happens is that the velocity in which two points "expand" away from each other is proportional to the distance, and the proportionality factor is given by the Hubble parameter.

No matter how small the Hubble parameter is (it is very small today, so for small scales we don't see expansion), there will always be a distance after which the expansion velocity will be bigger than the speed of light, so the light will be trapped inside this bubble of expanding universe.


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

[User] Does a black hole experience friction drag from the matter it is travelling through?

[Assistant]
There's something we call "friction", but it's not really friction in the same sense.

When a ball flies through the air, the atoms on its surface and constantly bumping into and interacting with the atoms in the air. These interactions transfer kinetic energy from the ball to the air, and the ball slows down.

For a black hole, it doesn't really *touch* things very much though, because space is very empty. Anything that hits it dead on will be accreted, and add its mass and momentum to the black hole. But it's pretty rare to hit a black hole head on like that. What generally happens is you form an accretion disc around a black hole that gradually drips matter onto it.

The bigger effect is what's called *dynamical friction*. This particularly affects supermassive black holes. When a supermassive black hole moves through a galaxy, it attracts the stars around it. The stars don't generally get sucked into the black hole. Instead, they tend to accumulate *behind* the black hole as it moves. There ends up being a higher density of stars behind the black hole than in front of it. These stars are all pulling the black hole with their gravity, and that means the black hole is being pulled backwards a little bit. This causes the supermassive black hole to slow down, and to start to spiral "down" to the centre of a galaxy. This is very different to how friction works on a ball thrown in the air, but we call it "dynamical friction" anyway.

For smaller black holes, scattering also acts like friction. If you have a black hole in a star cluster, it will have nearby encounters with other stars, most of which are much less massive. These random encounters tend to end up with the smaller star being thrown further out, and the black hole losing some kinetic energy and falling further towards the centre of the star cluster. Once a supermassive black hole gets somewhat close to the centre of the galaxy, the same effect also happens and this helps the supermassive black hole to fall into the very centre of the galaxy. This is another source of something like friction, but again it's not really friction in the ball-in-air sense.


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

[User] Why does cold water seem to quench your thirst better than warm water?

[Assistant] I seem to recall this question popping up here not so long ago.  Even without feeling really hot, a normal healthy amount of human warmth may still drive a little bit of sweat production.  In its own small way, a chilled beverage may reduce this warmth and inhibit sweating.  The end result is a sense of less need for hydration along with whatever actual hydration the drink provides.


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

[User]
Eli5 If two metals touch in space they fuse permanently. Why?

Is there any benefit welding in a vacuum on earth vs conventional welding?

[Assistant]
Well metal is just a grid of atoms really with electrons flowing between them. When you touch two pieces together on earth there is still air between them which keeps them seperate even if its a tiny amount bonded to the outside of the metal.

In space however theres no air so when you touch two clean surfaces of metal together the atoms on the boundry have no idea that they are two seperate pieces anymore. They just bond together like the rest of the metal.


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

[User]
[Die Hard] Would Hans and crew actually been able to use the Bearer Bonds?

Supposedly, using the destruction of Nakatomi Plaza as cover for the theft of a huge cache of bearer bonds, Hans and his crew were going to be set for life "sitting on a beach earning 20 percent," as Hans says wistfully.

But would he? Nakatomi would know what bonds they own, and most likely report them destroyed in the "terrorist attack", so the issuer would probably stop paying or honoring them. So they're just worthless paper now.

Also, how would they get the money/cash them in? Someone told me they're like a blank check, but even a blank check comes from somewhere, and using a check  from someone who's dead is kinda a red flag. And even if they are a blank check, so to speak, I still think somewhere someone would realize that some German dude is using a Bearer Bond connected to the Nakatomi Plaza disaster.

Is there an angle I'm missing? Honestly, I don't get bearer bonds and how they're gonna make some random guy rich.

[Assistant]
The owner of a bearer bond is not registered at all. Hence the name bearer bond.

Whomever has physical control of the bond is the owner.

Now this heist would have only worked at the very latest the 80s, no one uses physical bearer bonds anymore, its all electronic and thusly registered to a person or a institution. They stopped making them right around this time.

As for cashing them its easy, as long as  they have matured they are basically money. It would be like stealing 20 bucks from your parents, the bank treats money as money, thats it.


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

[User] How does light have the property of "bleaching" or removing color?

[Assistant]
A photon is able to break down a chemical bond if it carries enough energy. The energy of a photon depends only on its wavelength. Some molecules absorb longer-wavelength photons without breaking, dissipating the captured energy by some other means, but will be damaged by a photon with short enough a wavelength. After being damaged, the structurally changed molecule may no longer be able to capture the longer-wavelength photons, affecting the color of the material.

Also, short-wavelength light can modify some molecules into chemically active forms that attack colorant molecules.


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

[User] samples of lead may have slightly different relative atomic masses depending on their sources. why?

[Assistant]
Because of varying isotopic abundances.

Lead (Pb) has four stable isotopes: ^(204)Pb, ^(206)Pb, ^(207)Pb, ^(208)Pb. The relative abundances of the four stable isotopes are approximately 1.5%, 24%, 22%, and 52.5%, combining to give a standard atomic weight (abundance-weighted average of the stable isotopes) of 207.2.

That's just an average though lead samples from different sources around the world all have their own distribution of the relative proportion of these isotopes, which can differ (slightly) from the average percentages given above. For example, a lead sample with more ^(208)Pb content (and therefore lower content of the lighter isotopes) will have a slightly higher relative atomic mass than the global-avg 207.2.


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

[User]
I believe the ISS has been a complete waste of money. CMV

I accept that there have been valid scientific advances made with the ISS, but not nearly enough to justify the ridiculous price tag.

Can anyone name one single major achievement the ISS has made?

Furthermore, a significant number of the tests done could have been carried out by unmanned probes.

Of course whether a science experiment can justify its budget is always going to be subjective, so the best way to deal with this is to use relative measures:

At $150bn, the money spent on the ISS could fund the entire University of Cambridge for over a century.

The LHC costs less than a tenth of this and has achieved much more (I know that's subjective- but how many new particles has the ISS discovered?)

You could build and run hundreds, if not thousands of hospitals with the money.

CMV!

[Assistant]
Iss will be invaluable if we ever decide to send people to Mars or similar as this is the only place people have lived over a longer timeperiod in zero gravity ( well that and Mir ). If sending people to Mars is a worthy goal is up for debate of course. It is also practice for setting up and supplying lunar colonies, which could actually be comercially viable for HE-3 extraction.

Basically it is like saying the planes the wright brothers built were a waste of money. This is our first attempt (second if you count Mir) and the lessons learned are enormous for future space exploration and colonization.

This is in addition to the direct scientific discoveries from the only functional micro-gravity lab in existence, which is invaluable for nano-manufacturing, biology, chemistry and a host of other sciences and industries.


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

[User] [Lovecraft] Why are all these great immemorial diety-things, who possess power and nature such that its incomprehensible to us, spend so much time on or influencing the unremarkable planet of earth?

[Assistant] You assume they intend to influence Earth. They don't, they're just so pervasive that there mere presence influence us. Every known species in the universe, and in the Dreamland, has been influenced by them. Earth's influence isn't special.


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

[User] ELI5:Is there anything you can do to stop a natural death? Does constantly replacing organs/parts of body work?

[Assistant]
There already is, but the body just keeps finding new ways to die.

Short version is most older people (60 range) develop heart conditions we treat with medicine. Now most 70 year old people may get treatable cancer. So now in their 80s, these people develop another condition we treat. In their 90s, they get Alzheimer's or Parkinson's.

Hypothetically at age 100 they may develop liver and kidney failure. We fix that, 110 they may develop some new unknown disease and so on.

TL-DR; You cure something that saves someone who's 80, when their 90 they get something previously unknown.


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

[User] CMV: Bikes are not cars and as a rule should not share the road with them, unless there's a clear shoulder or dedicated bike lanes.

[Assistant]
The premise of the argument is inherently wrong; OP assumes motorists have the primary claim on the road and already drive appropriately.

The fundamental problem with viewpoints like that is the road was designed for all forms of traffic. One could just as easily argue in an urban setting roads should be for pedestrian traffic with bikes and mopeds tolerated, but cars only allowed at very low speeds in specific instances. That particular model is often seen in older European cities.

Essentially, no view can be changed because OP is not willing to enter into a discussion about the purpose of roads and ideal public use of that resource.


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

[User]
Why are cats so much more focused on cleanliness than dogs? Is there an evolutionary advantage for cats to remain clean and no such advantage for dogs?

I was watching the cat at my work clean herself today, and I realized that dogs only tend to lick themselves when they're wounded. They don't clean themselves the way cats do. If they're both predators I don't understand why it would be more beneficial for cats to remain clean and not for dogs to stay clean.

[Assistant]
Cats and dogs are predators, but they have very different hunting strategies.

Dogs are chasers.  When they find prey, they run them down and kill them.  Cats are pouncers.  They lie in wait and strike when prey is in range.

The difference means that it's not very important to a dog if the prey knows there are dogs in the area because the dogs are going to chase the prey down if they run.

Cats are very particular about their hygiene and elimination so as not to drive the prey from their territory.


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

[User]
[Star Trek] How does everyone communicate in real time, when sometimes it takes hours or even days to reach the area by spaceship?

For example: Captain Sisko talks to his dad real time while he is on Deep Space 9 and his dad is on Earth. Earth is ~52 light years from Bajor/DS9. If Sisko were to take the Defiant to Earth traveling at maximum warp (warp factor 9.5) it would take him 10 to 11 days.

[Assistant]
Subspace communications travel faster than ships at warp speed. It's like how its faster to phone a friend than to drive to his house.

Edit: just to be clear, they operate by two different means. Communications travel through subspace and ships warp real space.


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

[User]
[Power Rangers] How come the Power Rangers don't go straight to their Zords when the monster of the week appears?

Those monsters do quite a bit of property damage even before they grow. I think the Rangers could just go ahead and step on the bastards as soon as they pop out.

[Assistant]
You might as well ask "why doesn't a cop pull out a gun every time he encounters a criminal?"  Simple - the Force Continuum.

The Force Continuum has nothing to do with the morphing grid.  Very simply put, a situation is as bad as whomever is putting the most into it.  Yet, in order to stop a situation, you have to be the one with the *most* force in the situation.  So, we have a dillemma:  how can you reliably stop monsters without making the battle worse than it has to be?

With the Force Continuum, Power Rangers - and cops - are taught what is reasonable.  You are taught to go *one higher* than whatever the foes are using - *no* further.

Each armed force generally has its own force continuum based on the laws it is responsible to and the foes it encounters - so don't take the Power Rangers, an extralegal organization, as representative of the Force Continuum used by actual armed forces.  Also, their exact tactics generally aren't open for public discussion - they often seem to *match* the level their foes are using, counting on their technological advantages to carry the day.  That said, here's what's observed:

1.  **Presence.**  Just being present is a use of force - and can prevent action.  *Example:  When the Tenga approached a playground, the Power Rangers appeared.  The Tenga left without actually attacking.*
2.  **Verbal Commands.**  Exercising your authority as a Ranger - even if it is only an authority granted by virtue of that giant robot you're known to ride around in - is definitely force.  *Example:  In the middle of a museum robbery, in perhaps the only time verbal commands has worked, Rito gave up when commanded by the Power Rangers to give up.*
3.  **Unarmed Combat.**  Although this imposes the greatest risk on the Rangers, it contains the combat to a small area - less risk of property damage.  *Example:  Whenever the MOTW doesn't give up, unarmed combat begins.*
4.  **Armed Combat.**  Although modern magic and interstellar technology make armor incredibly effective, weapons are still potentially lethal, and not called for until a foe is at least *intending* to kill someone.  *Example 1:  When the later Putty Patrollers start attacking with swords, the Rangers begin arriving to battlefields with their 'numedieval' weapons already out.  Example 2:  The Rangers will pull their sidearms on anyone that harms an innocent.*
5.  **Heavy Weapons.**  The Rangers do have a limited number of heavy weapons.  *Example:  Many MOTWs, once they have demonstrated a willingness to kill or harm, may find themselves on the receiving end of a United Blaster or Power Cannon shot.*
6.  **Vehicles.**  The land-borne Shark Cycles and the airborne Battleizers provide an armor and mobility advantages over prior levels, while not being quite as destructive as a Zord.  *Example:  The one time that the Tenga brought a mounted rocket launcher to the party, the Power Rangers skipped all prior levels and immediately went to the Battlizers.*
7.  **Zords.**  When possible, the Rangers are taught to use their individual zords.  This was rare with early Rangers - as the Zords were primarially there to keep the superweapon from being 100% functional if any single part were captured - although it became much more common later (esp. Turbo and SPD).  *Example:  Just the Sabretooth Tiger was enough to stop a one monster menacing Angel Grove.*
8.  **Megazords.**  Rita's power as a sorceress is enough where they often have to skip the prior two levels entirely.  *Example:  Just look anywhere in Angel Grove for the footprints.*
8.  **Ultrazords.**  Even more powerful than the Megazords, the massive destructive potential of the united Ultrazords make it so they are rarely called forth.  *Example 1:  Dischordia, a 'more powerful' ally of Master Vile, had to be taken down by the Shogun Ultrazord to prevent any Ranger from coming any further under her compulsions.  Example 2:  The only time two Ultrazords were fielded against one foe was against the planet-breaker Serpenterra, which is so off the Force Continuum as to be silly.*


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

[User] ELI5: Eristothenes measured the circumference of the earth by measuring the shadow of two poles, miles apart, at the exact same time. So how did he know the poles were being measured at exactly the same time in an era when people used the sun for timekeeping?

[Assistant]
By doing it at local apparent noon. This is, by definition, the time of day when the sun reaches its highest point in the sky. If 2 places are on the exact same line of longitude (i.e., directly north and south of each other), local apparent noon will occur at exactly the same time in both places. You can, of course, measure this with a sundial.

It turns out that while close, Alexandria and Syene (modern day Aswan) are not directly north and south of each other, which introduced some error into his calculations. Still, they're close enough that his measurement was remarkably close to the correct value.


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

[User]
eli5 What do people actually do in space stations?

What do they do in space that they couldn't do on earth? Are they just doing experiments on things in a zero gravity environment? Is part of their goal to help people live on other planets?

[Assistant]
So a large part of what astronauts specifically is maintenance. Replacing and adding modules and the like. Doing stuff in space takes way way more time. Especially if something goes on the outside of the station. Watched a spacewalk take 8 hours to run an Ethernet cable to an exterior camera.

Inside they are also run support for experiments. Many experiments go into these neat little modular racks and can be monitored and run remotely, but there need to be hands on site to set it up, or change bits out. Others aren't really capable of being operated remotely so they just do them directly.

As for what experiments need to be done in zero g a lot of it is research for long term space travel. For potential missions to the moon or Mars for example. Stuff like studying how zero g and radiation exposure affects fertility in animals, growing plants for food, water recycling, cement mixing, combustion, etc.

The astronauts themselves are also closely monitored to see how their bodies react, so just living in space is an experiment in itself.

Also some time dedicated to education, like doing demos, or running a couple experiments developed by students.

Some neat protein crystal growth to potentially support development of novel drugs. There's a lot of interest in microgravity manufacturing for stuff like drugs or like silicon for computer chips. If something interesting is found actual production would probably be run on automated satellites, but for research having humans there to run the stuff, and sharing rides with other experiments going up and down makes it a lot more economically feasible to research.


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

[User]
ELI5:Why is it almost all animals can drink from lakes, ponds, etc, but humans must treat the water first?

My dog, deer, etc, drink out of a near by pond with no repercussions but any human would run the risk of dysentery drinking out of the same source.

[Assistant]
Humans can, actually. But they have to do it since birth and keep doing it.

Humans are born with a remarkable amount of strong gut bacteria, that allows them to do things like eat spoiled meat and drink from nasty ass water. But, since those bacteria are highly specialized, if they're not used they die off.

That being said, animals aren't immune to giardia and the like, dogs get it a lot from doing this.


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

[User]
ELI5: If your body is constantly replacing skin cells with new ones, why do scars last a long time?

From what I've learned new cells "know" what to be based on your DNA (though I could be wrong on this one). Since injury does not change your DNA, it should not affect the color or arrangement of new cells.

[Assistant]
Your outermost region of the skin, the epidermis, is made of a number of sublayers, and _new_ skin cells are only made in the bottom sublayer. These new cells divide and move up the skin layers until it reaches the surface and sloughs off.

A shallow scratch damages the top layers of the cells, and the wound heals when new cells move up to replace them. A wound deep enough to damage the basal layer will hurt those dividing cells. Without a source of new cells, your body compensates with a make-shift network of proteins to connect the tissue - that's why a scar looks different from surrounding cells.


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

[User] ELI5:Why is gold the standard of wealth when things like iron, wood, or food may be more useful and fossils (ie) may be just as rare.

[Assistant]
A few reasons:

1. Gold is rare. If you're going to use something as a medium of exchange, you need it to have a stable supply. You want to know that when you accept a gold coin for your goods or service, it will still have a similar value next year when you spend it.

2. Gold doesn't tarnish, so you can store value. Iron rusts, wood rots, food spoils. We still find gold coins from the ancient world that are in good shape today.

3. Gold is very dense. At the time it started to be used as a currency, it was the most dense metal known. This made it impossible to counterfeit, as any additives would decrease the weight of the coin and be immediately identifiable.

4. Gold is easy to work with. It is soft and melts at a relatively low temperature. If you decide your gold coins are too big, you can easily melt them down and recast them into smaller coins.


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

[User]
Even though Jurrasic Park is fictional, is the science possible to make extinct animals alive once again using extremely old DNA?

How would it work?
Does DNA go bad?
What would be the errors in creating extinct animals?

[Assistant]
The half-life of DNA is such that you'd never get a decent enough sample of a dinosaur to clone it. A mammoth though? Sure.

Assuming we did, by sheer dumb luck, somehow find a dinosaur so well-preserved that we could somehow extract a complete enough genome to use to clone the animal though, a new set of problems would arise. Firstly, you need some kind of similar creature to bear the organism as a surrogate mother. With a mammoth, an elephant should do just fine, but a dinosaur? There aren't any reptiles large enough to lay a T-rex egg. Even if you did somehow grow the dinosaur in-vitro in a prosthetic egg or something, you'd still only have a genetically similar (not identical since some damage is inevitable which must be repaired with, for example, frog DNA) creature, not an exact replica. For example, you'd have no way to teach it how to be a T-rex, since we have no idea how T-rex behaved and no similar animals to be a surrogate mother.


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

[User]
[Arkham Knight] Why hasn't someone called the National Guard?

Seriously, have you guys seen what's going on down there? These random mercs have pretty much taken control of the whole city! I'm pretty sure I overheard one guy say something about how he "wishes they would bring in the National Guard," so why don't they just do it?! I mean seriously...the fear gas cloud?! How is one man in a batsuit supposed to handle that on his own?

Ugh. I'm voting for someone else in the next election.

[Assistant] They have, but the entire incident takes place over a few hours, and it'll take a while before they're ready to enter Gotham. You don't want to just rush into a fight with a large, well organized, well equipped force, especially one that is sitting atop an unknown chemical WMD.


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

[User] [Terminator] So if time travellers can go back in time with their hair, why don't they wear wool clothing?

[Assistant] Sheep are no longer that common in the war blasted landscape of the near future. Most of the clothing the resistance had been able to scavenge ends up being synthetic fibers, as those break down less easily than natural.


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

[User]
CMV: University lecturers should not be allowed to express their political stance and should come across as neutral as possible.

I'm currently a commerce and media student at University and I have noticed that the majority of my lecturers are very expressive and passionate about their political views. I myself do not have a strong stance and revise parties and policy before each voting year, I believe that there's a place for all main political parties within a society (I'm not asking you to change my mind on that).

I believe that when lecturers / professors express personal political views it could be detrimental as it puts a pressure to conform onto free thinking individuals. Lecturers should discuss facts but not opinions as they are there to educate not convince.

When it comes to assessment, essay writing for example, knowing that the lecturer has a bias can put pressure on an individual to conform and argue towards that stance in order to feel accepted, correct and attain a good grade.

Students who happen to be opposing the lecturers bias may also feel singled out, incorrect and alone when other students laugh and agree with remarks made by the lecturer. Lecturers also make rude comments about certain politicians and I feel that it is highly unprofessional.

So basically, personal opinion and emotion towards politics should be kept out of education and students should be fed thought stimulating facts and information instead.
Change my view so that I can relax and get on with my study!

*Update: lesson of the day is that it is really difficult to communicate a point via just text. A redditor has pointed out to me that I am complaining about political gossip rather than political biases as a whole and I agree.

[Assistant]
Professors expressing their political opinions is important because there is no way to just express objective facts because at the very least due to restrictions in time one will still have to choose which facts to share. And even attempting to be as objective as possible it is impossible to do justice to all possible opinions around a controversy.

Therfore a professor expressing an open bias allows you as the audience to understand the perspective they are coming from when interpreting the facts of an event.


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

[User]
How are bugs able to fly by just moving their wings up and down? Wouldn't the down stroke just be counteracted by the upstroke?

What I mean is, when they're moving their wings down, they're pushing a certain amount of air down. But when they pull their wings up, aren't they pushing the same quantity of air back up? So no net air movement? How do they fly?

[Assistant] The wings don't go up and down in the exact same way.  If you've ever been swimming, you have first hand experience.  When you bring your arms forward, you do it in such a way that they have little surface area, so you push very little water forward.  When you bring your arms back, you spread your arms out, so you push back a lot more water.


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

[User]
[Star Wars] If the Emperor had pushed for better galactic living standards, would the Rebellion still have happened?

I understand that there were political and ideological motives for the Rebellion.

With that being said, the majority of front line troops and operatives weve met, either came from abject poverty and oppression, or had their family murdered by the Empire.

I cant help but think that if the Empire had instituted better healthcare and a living wage, then the Rebel Alliance wouldnt have had much luck in recruiting troops.

[Assistant]
If were still assuming that some planets are being harshly oppressed then yes the rebellion would have still happened albeit a bit smaller no doubt. The thing is while a lot of the people we see have personal beef with the empire, thats not true for all of them. There were many people we see - Mon Mothma, the Organas, Biggs Darklighter, just to name a few - that really didnt experience horrible tragedy at the hands of the empire personally but decided to join because it was the right thing to do, because they knew that the empire was treating others with absolute unjust cruelty.

So the empire couldnt just expect to coax people out of a rebellion by making *some* improvements but still retaining the core elements that made it such a horrible regime. But a *legitimately benevolent* empire would have absolutely staved off a serious organized rebellion.


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

[User]
ELI5: I often hear that "in western society, breasts are sexualized but in other places [I commonly hear Africa], they are not sexualized and therefore not as big a deal." So why is it different in western society, why did they become sexualized?

I am aware it has to do with media but what happened that the media decided to make breasts sexualized objects?

[Assistant] The Abrahamic religions stress modesty in women. These religions were central to the rise and formation of Western culture. So even though religion is becoming less important in the West, the old cultural standards are still in effect.


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

[User]
Are there any possible dangers to using solar energy?

Could storing solar energy instead of letting it go its own way affect weather patterns? Some other type of changes I'm not thing of?

[Assistant]
1) Will our climate/weather be threatened because of the redistribution of solar energy/heat, etc. due to large solar panel coverage?

 No. The sun illuminates the planet with approximately 90,000 TerraWatts of energy at all times. All of humanity currently requires about 17 TerraWatts. Let's say we're ambitious and increase our energy consumption by an order of magnitude (up to 170 TerraWatts). That would still be less than 0.2% of the total solar flux being converted to solar, much of which would be converted into heat anyway because of the inefficiencies in how we use power. The largest impact solar is likely to have is on the reduction of carbon emissions, but the overwhelming scientific consensus is that less carbon will be healthy for earth's climate.

2) Are there environmental problems (materials scarcity, safety hazards, disposal, etc.) associated with the production, maintenance, and disposal of solar panels?

This is very technology dependent. Most of the current solar backbone is built on Silicon, which is an extremely abundant, inert material. Cadmium Telluride, on the other hand, is also a reasonably popular technology is quite rare (because of Tellurium), and quite toxic in the wrong exposure circumstances (Cadmium). In that case, there are quite a few things to consider. More speculative solar technologies, such as organic solar cells, III-V's, and perovskites will have their own issues as well, but have not yet been studied deeply.


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

[User]
Academia who started their PhD at 35+ y.o. ... how is your professional life since you finished your PhD? Did you have any age-related issue?

Well, "Academia" or anyone with a PhD, heh! :-)

[Assistant] Could you at least say what your concern is and what field and country you are in? That might make a difference. For example, a Ph.D. in the US is usually at least two years longer than in Europe, for example.


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

[User]
ELI5: Why can't humans live in Chernobyl, but the wildlife there seems to be flourishing?

I recently watched a documentary on the wildlife in Chernobyl, and it seems like, especially, the wolves are thriving, but it cannot sustain human life. Why?

[Assistant] Chernobyl can just as easily support human life as it can any other life. The difference being, we generally do not find the increased background radiation to be an acceptable risk. For many species of wildlife the background radiation will not decrease their overall survival rate by much, because life in the wild is pretty grim for most animals. Hell, chernobyl might even being doing the wildlife a favour in that the radiation has probably resulted in a higher than average mutation rate, which means evolution will be pushing the wildlife there harder to be the best fit for their environment.


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

[User] ELI5: How can we sleep at night without any pimples and wake up with a big one? how do pimples grow overnight?

[Assistant]
If you look really close, we humans are covered in billions of little holes that leak all kinds of liquid, all deliberately though, our skin likes covering itself in oil and sweat, even if we think it's icky.

While we are awake we sometimes feel that ick, and do something about it like wiping or washing. While we are asleep we just throw our face at a pillow and lie there for a while, so any ick that wants to come out sometimes can't because the pillow is in the way. Sometimes that seals the hole that the ick was trying to escape through, making it worse. No big deal, our skin can puff up and carry this excess ick till there's another way to get rid of it. 'Popping a zit' is basically forcing a brand new hole in your face for the ick to escape from, which is super icky and actually damages our skin, but our skin is amazing and grows a new layer, pushing that old and punctured layer off.

Most dust and dirt in a home is human skin falling off the very surface of us. Sounds scary, but all part of the plan :)


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

[User] Why is it that some people get eaten up by bugs while others seem to remain untouched?

[Assistant] Specifically in regards to mosquitoes, they have a preference for certain blood types and other blood characteristics which they can actually smell. First off, mosquitoes find their way to humans by following CO2 gradients in the air, simply the way you breathe and how much CO2 you exhale might make it easier for mosquitoes to make their way to you. Additionally, various factors like type-O blood, pregnancy, and even beer drinking have been shown to attract mosquitoes. Another is the presence of lactic acid in sweat, which would occur with recent exercise. Other added scents from the soap, shampoo, deodorant, and perfumes used as well as clothing, recent food smells, the particular makeup and activity of our microbiome, etc. might attract or deter mosquitoes preferentially.


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

[User]
What actually happens to a country's job market when the minimum wage is increased?

So, over here in New Zealand, the opposition government is making noises about raising the minimum wage from $13.75 to $15 iffen they get elected. There's been some "eeeh" reaction from people I know who are currently unemployed and seeking work, who say that raising the minimum wage is all well and good, and it'll stimulate the economy, but it will mean that companies will be even less willing to give job-seekers a foot in the door than they are now, what with the whole ongoing economic recovery.

So, thought I'd take it to the folks who actually study this sort of thing for a living and ask the economists: what happens to a country's job market when the minimum wage is increased? Both in a historical and an economic model sense.

[Assistant] Attention day traders and armchair economists. We're glad you enjoy your hobby, but please leave this post to the pros. Unless you have a relevant background and can answer follow up questions in detail please refrain from answering. Let's keep this science-y!


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

[User]
[Star Trek] Why isn't there a Starfleet protocol to keep all these crazy officers from taking priceless archeological artifacts with them on ships that are prone to attack?

Picard has several ancient items, as does Sisko. Surely those are not the safest places to house such items.

[Assistant]
Ships aren't actually all that prone to attack.  Well, the Defiant is a little bit, but Sisko doesn't keep his valuables on-board.
Beyond that, what an officer chooses to include among their personal belongings is up to them.  It's up to them to weigh the risks of bringing any particular valuable item onboard.


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

[User]
Is there always a geosynchronous orbit for artificial satellites around an Earth-sized planet?

I may not even know enough to ask this question properly.

I want to imagine a planet with a very long day so its rotational speed is low. Is there a geostat that doesn't require much station keeping even for a planet whose day is 100 Earth hours? 500?  Or does it get to a realistic point where you'd have to be so far from the planet that there's not enough gravitational attraction to keep you in a stable orbit?

Thanks very much for your time.

[Assistant]
If the planet rotates slow enough then the synchronous orbit could be far enough away that the star's gravity dominates over the planet's (outside the Hill Sphere of the planet).

An extreme case would be a planet that is tidally locked to its star and only rotates once per year and one side is always facing the sun. The satellite would have to be at the L1 or L2 Lagrange Points in order to remain fixed with respect to a point on the planet's surface.


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

[User] How is water able to stay in gaseous form in air (water vapour) well below its condensing temperature?

[Assistant] All liquids have what's called a vapor pressure. Essentially, if you leave the liquid sitting open to air it evaporates, often very slowly, until there's a certain concentration (partial pressure) of it in the air. The vapor pressure also depends on temperature, which is why hot air can be more humid than cold air.


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

[User]
Funded PhD offer - should I accept it?

I have been offered a fully funded PhD (humanities, in the UK) and just spent a whole day (and a sleepless night) pondering whether I should accept it or not. I would really appreciate any advice! Basically:

I have always planned to do a PhD at some point, but "at some point" is key here. I am currently finishing my MSc and planned to take a break from studying to pursue my professional career. My industry is extremely competitive but I am currently quite well equipped to get into an entry level position (I have done several internships, have good networks etc.). My main (only?) PhD-related worry is that dedicating three years to a PhD would harm my professional career - in three years I could have already moved on to a better paid managing position. Instead, by the end of it, I will be 29 with very limited industry experience.

However. As I mentioned, a PhD is something that I have always wanted to do - I thrive in academia, enjoy research and I know that at some point I would want to do it for my personal development. I applied for this studentship despite the timing because this is such an incredible opportunity, with full funding (tuition and maintenance) and a really unique and interesting research question. The project involves some professional work at amazing companies, and the topic pretty much aligns perfectly with my personal interests. I knew that I would regret it if I hadn't tried, but it was so competitive that I never expected to actually get the place (hello, impostor syndrome).

So I suppose the question is, what do you think would be the best decision in my circumstances? Do I accept the offer and take those three years out of my professional career (assuming that I would get a job soon), or do I leave it and wait for another opportunity in the future? Any thoughts would be so appreciated!

*EDIT*: Thank you so much for your comments, everyone! This thread has been so encouraging. After reading through it and speaking to my friends and family some more, I have to say that I am leaning towards accepting the offer. I will still take some more time to think that through but I've actually allowed myself to get excited about the idea of doing that PhD (and it feels great).

[Assistant]
If you start working in industry, you'll get accustomed to career money. It is very much like an addiction. You take on things that make it very hard to go back to stipend money.

Regardless of how good the opportunity is, it *could* be your only chance to do it without suffering harshly. On the other hand, it is nice to have some money.

If you accept it, can you defer it for a year to get yourself a break from academia on the way in?

This is just food for thought, others will have better perspective.


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

[User] [Star Trek] Why does the transporter need a pad or platform on the ships? Why can't people just beam from anywhere on the ship?

[Assistant]
They can, but it takes extra energy and is less efficient.   As you might have noticed it's usually only done in times where it's an emergency or much more practical to do spot-to-spot transports than transport-pad to/from location  (eg beam them directly to sick bay, etc).  They have even transported people directly from one location on the planet to another.  (far less often).

A typical transport has the subject being transferred at the transporter pad and into the transporter pattern buffer.   Then REMOTELY re-assembling that pattern elsewhere (planet surface, nearby vessel, etc) -- or in reverse, REMOTELY transferring the subject into the transporter buffer, and then re-assembling locally in the transporter room.   The "remote" portion of the process is the intensive part on the technology.

Now add the notion of receiving the subject remotely, into the transport buffer... then re-transmitting it remotely simultaneously to another remote location.

The transporter system is (in essence) doing twice the work.   It probably also has a greater margin of error should any portion of that signal be disrupted.

Star Trek Discovery spoilers:  >!In the 31st century we come to find out that transporter tech now fits in their com-badge.  There is no more transporter room, and they do indeed transport from point to point. !<


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

[User] If you put an air bubble inside water while in zero gravity, will the bubble try to find its way out of the water?

[Assistant]
No it wouldn't. The reason bubbles normally rise in water is due to a difference in density, which under gravity causes a resultant force where the force of gravity on the water is greater, causing the water to "fall" and the bubble to rise.

In zero-g, the difference in density doesn't result in the same net force and expected behaviour.

Additionally, some of the comments have stated that the water would "expel" the bubble to minimise surface area due to surface tension, but without any additional energy input, the state in between "bubble in water" and "bubble out of water" has a higher energy than the initial state, which requires some sort of activation energy to proceed.


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

[User]
[Star Wars] How powerful is Luke compared to prequel Jedi?

Is he just assumed to be the most powerful Jedi of all time because all the other Jedi were wiped out? How would he stand in a fight against Mace Windu or Anakin?

[Assistant]
Largely depends on the timeframe and canon. During time of the movies, he isn't exactly an epitome of might - while he did defeat Darth Vader, the Palpatine went down only due to very specific circumstances that didn't rely on Luke's power in the Force or with a lightsaber. He probably wouldn't stack up very high in the Prequel-era Order, he's alright, but much work needs to be done with his training.

Now, post-Endor, Luke actually had time to work on his self-education. While new canon info is scarce, it seems that in both canons he travelled the galaxy uncovering the lost jedi lore and teachings. So by the time Luke trains his new Jedi Order he's a legit Jedi Master, who probably won't go down without a fight against Windu or young Anakin.

By the time he is so-called "Grandmaster" Luke, he essentially learned nearly all there is to learn about the Force, and more or less living repository of Jedi lore. At this point it's better not even try to fight him, since he probably already learned an obscure power specifically for this occasion.