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

[User]
CMV: As a black person, I don't see the merit behind minorities lambasting oppressors of a different ethnicity before holding members of their own community accountable

This isn't an attack on POC. I do not believe any community is a monolith and I know that true progress doesn't happen overnight. I try to call out people that have an overreliance on victimhood or that use buzzwords without really expressing an apt description. I get demonized and insulted regularly for this. I'm hoping to use this opportunity to assess my own opinions and whether they hold up to criticisms.

Some more specific examples include the concept of reparations for the Atlantic slave trade. I don't believe that chapter of Americana should *ever* be forgotten. I don't think it should be a cudgel with which to beat a white person over the head with when their family emigrated from Ireland and they faced a whole different set of xenophobia and jingoism. I think the lessons should be taught as history and work best when referencing implementing solutions. Justice Thurgood Marshall was sharp in how he addressed Jim Crow and Civil Rights when talking about Affirmative Action but a key point he intimated was that this should advance "with all deliberate speed". I fully acknowledge the abuse and torment of those entrapped in the Atlantic slave trade. I believe those people that ask for reparations are essentially asking for a divestiture of wealth accumulated over generations. It manifests in the form of people giving up jobs at 'white-shoe' firms to the best candidate as opposed to a crony and that takes generations more. My qualm is that members of the majority ethnic group are villainized for their very existence. If this level of animosity was turned to your local neighrhood crip gang member, they would be eradicated.

That brings me to the violence in the black community. I cannot fathom how this is the fault of anyone but the people perpetrating these acts. I'm extremely ignorant on how oppression compels you to gun down another for respect or street credibility. I (silently) lose respect for the people that defend these murders under the guise that they are products of their community or it wasn't in their ability to not commit violence. I'm not an expert but I've found no other comparison of people being absolved of guilt because of vestiges of systemic racism occurring any-number of years prior.

Please let me know what didn't make sense or why I'm uninformed here.

EDIT: I've been permanently banned from this sub. It wasn't mentioned why but I assume it was the fact my opinion was just  tad too unpopular.

EDIT: I was never banned from this thread. I misread a message I got from a mod. This is probably a great reason new accounts are discouraged from posting right away. For all the folks calling me a troll or white supremacist for being new, I promise I'm just late to the party. This site is still cool though.

LAST EDIT: so i don't have to type in replies anymore, when I said policy reform shouldn't come "before" internal accountability,  it's because they're both equal.

[Assistant]
So black people have to fix 100% of the problems in their community before they can address the problems of racism and oppression from the outside?

Seems like an unreachable objective that would permanently delay progress.


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

[User]
[DOOM - any and all continuities] If a way could be found to prevent possession, or if the forces of Hell were unable to possess people for whatever reason, would they stand a chance against Earth's forces?

Assume that a portal opens up and humanity has to close it (or invade and occupy Hell, I guess).  The forces of Hell want to invade and occupy Earth.

It seems like their big advantages are:

Teleportation (but they don't seem to abuse it as much as you'd think it would make sense to).

Possession- they don't even need to take over places the normal way when they can just possess everyone there and make them into demons/quasi zombies.

Corruption- in the more traditional sense.  They just find some useful idiots to go turncoat and screw the rest of humanity over for dubious benefits.

That last one might be their strongest asset, given the overwhelming technological advantage we have.

As it is, without a human grafting tech to their demons, Hell's forces are pretty much restricted to possessing humans who can use human weapons, or whatever they can innately do (spitting fireballs, scratching and biting).  OTOH we humans can slap some high tech weaponry into any schmuck's hands and with some minimal training (point and shoot, stay calm under fire) they can be as strong as anyone else, at least at range.

Or, as I put it in Call of Duty: "It turns out that stupid people's bullets hurt just as much."

I'm not saying the conflict wouldn't be bloody, but would Hell have a chance of winning without possession?  Maybe if they had infinite reinforcements they could eventually overwhelm humanity, but even without considering the heavier stuff we have at our disposal, our small arms seem more than a match for demonic forces that cannot simply possess the majority of us.

[Assistant]
Demons are incredibly durable even the weakest specimens requires sustained small arms fire to kill. Larger demons require no less than anti armor weaponry to down, don't require food or sleep, and can cut through heavy armor.

Your overestimating the effectiveness of an average soldier, in combat it takes several thousand rounds fired to kill an enemy combatant. That's with human targets, imps rarely stay on the ground or attack in a large clump, hellknights will charge straight through any defensive structure you've built and sow unparalleled chaos, Pinkies will soak everything short of an anti armor explosive.

Our biggest advantage would be air superiority and even that won't last without infrastructure . Hell would either straight up win or severely cripple humanity us.


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

[User]
Are pacemakers able to adjust their "heart rate" based on the exertion of the person they belong to? Do they support a feedback system with the body?

I was thinking about this today, since someone's heart rate fluctuates even as they just stand up, do pacemakers have a way of dealing with such fluctuation? And if they can, to what extent can they support changes in heart rate? Could a pacemaker patient go for a run, or participate in extreme sport, for example?

[Assistant]
Pacemakers generally regulate pacing at a lower boundary; this lower boundary is usually set by a cardiologist.

Pacemakers do not, however, regulate every heart beat. Aside from other contraindications there is no reason a pacemaker patient cannot run, exercise, or live a normal, healthy life. Their heart rate will increase, yes, but the medical device has nothing to do with this. It will only intervene when there is a missed beat or arryhtmia.

EDIT: This is not entirely accurate, particularly some different styles of pacemakers; there are pacers that will regulate maximum limits as well as constant heartbeat. Please see corrections in comments below.


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

[User]
If we ever wanted to start populating another planet, what the fewest number of men and women you could send so there wouldn't be any incest among the offspring?

If we ever wanted to start populating another planet, what the fewest number of men and women you could send so there wouldn't be any incest among the offspring?

[Assistant]
Probably a few thousand, maybe less. If your familiar with human genetics you'll realize once the population reaches a certain generation, everything's incest and inbreeding. In fact, genetic diversity in humans is pretty low compared to other animals.
The more important question would be how many individuals would be needed to keep recessive deformities to a minimum. You can't really put an ideal number on this because there will be genetic deformity in a certain percent of the population no matter it's size.
I say let's put all of Hollywood on Space-X, aim it at A. Centari and hope for the best.


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

[User] ELI5: How do you explain the difference between sympathizing with someone and empathizing with someone?

[Assistant]
Sympathy is the act of understanding someone else's emotions. Empathy is feeling those emotions yourself.

For example, if a friend's parent recently passed away you might feel sympathy if you understand that they are sad. But, if you also had a parent pass away you can remember the same feelings you had at that time. So, you can empathize with the person because you feel (or have felt) the same way they do.


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

[User]
Is there a single language I could learn that would allow me to write code for iOS, Linux, and possibly even micro controllers such as the Arduino?

I am currently a mechanical engineer with a little bit of basic electronics knowledge, and have spent many years running various flavors of Linux and writing small bash scripts to automate various tasks. So I'm not exactly starting from 0 when it comes to learning programming...but still only at maybe a 1 out of 100, lol.

I am equally interested in coding for hardware, micro controllers, sensors, etc, think IOT devices as well as apps for iPhone, iPad, MacOS, and Linux. But I dont want to end up overwhelming myself by trying to learn multiple languages at once. So is there any 1 language that can be used on all these platforms?

[Assistant]
C or C++ is going to be essentially you're only option. Microcontrollers don't usually have support for other languages.

Unfortunately the Apple ecosystem is particularly locked down, to write apps for their products you *have* to use an Apple computer and an Apple programming language (e.g. Swift) is strongly recommended. You can use C++ (using e.g. Qt) but it won't be the easiest experience.


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

[User] I'm predicting 60 events to happen over 30 days, randomly distributed. How many days with zero events can happen in a row before I'm statistically unlikely to meet my target? Is this something the Poisson distribution applies to and how can I calculate it?

[Assistant] yes, the poisson distribution can be used, but it requires that you know the probability of the event happening.  are you saying that the probability is 60 events every 30 days or are those just some numbers you're making a bet about or something?


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

[User]
[Star Trek] Why are there so few artificial lifeforms and AIs running around?

As far as I know, the only forms of artificial life are the androids designed by Noonien Soong, the "machine race" from the V-ger incident, and the occasional self-aware holodeck program.

What is it about the Star Trek universe that gives rise to so few AIs/artificial lifeforms compared to other scifi universes?

[Assistant]
There are several factors.

One is that functioning, stable, artificial lifeforms are very difficult to produce. Dr. Soong's android Data is the only known fully autonomous artificial being that isn't either dangerous to biological life (like his brother Lore), or prone to catastrophic malfunction (like his daughter Lal). Records of the encounter with the androids associated with Harcourt Fenton Mudd indicate that they are both dangerous, plotting to take over the galaxy and "protect" humanity by effectively enslaving us, and fragile, capable of being destroyed by simple conversational logic loops. Research tends to indicate that, left to its own devices, artificial intelligence has a habit of spinning into one neurosis or another, and that placing such intelligence in an autonomous body causes even an even greater likelihood of malfunction.

Another issue is that the Federation is highly cautious about the ethical dangers of creating artificial beings. The transcripts of the trial of Lt. Commander Data are an excellent real world exploration of the subject, and there have been huge amounts of further discussion on the topic. In essence, the danger is that we would create artificial life, and then enslave it. The incident involving the exocomps is also worth looking at. In that instance, there were robots designed for hazardous work, but with the ability to learn. They spontaneously generated a form of sentience and a sense of self-preservation. This indicates that, given the proper conditions, it is possible for a low-functioning machine intelligence to grow to a higher-functioning one. Again, we run up against issues of both the rights of sentient beings, and the dangers of allowing machine intelligence to develop. It is possible that, if allowed, the exocomps could have developed into friendly machine life. It is also quite possible that they could have developed into incredibly dangerous machine life.

The fact of the matter is, machine intelligence is an almost impossible balancing act. On the upper side of intelligence and complexity, you have machines that spin up into neurosis and malfunction. On the lower side, you have machines that aren't intelligent enough to serve any useful function, and are essentially dependent on their caretakers. In either case, machine intelligence carries more costs than benefits. Well-adjusted artificial beings, like Data, are almost totally unheard of, because that balance is so difficult to reach.


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

[User]
ELI5: How would modernizing infrastructure help us?

I'm curious to hear from somebody who knows this kind of stuff

Im guessing it makes us safer, gives 'right now' jobs for awhile. It would save energy (the electrical grid waste something like half of all electricity produced, that's a lot of waste).

[Assistant] you pretty much answered it yourself. the national infrastructure is composed of lots of different parts though. road networks, fibre optic internet, train tracks, etc etc. a better infrastructure makes for a more efficient country, with less waste. and improving things can create shortterm jobs, while maintenance of the infrastructure already provides longterm jobs.


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

[User] [Luke Cage] Shouldn't the guns break when Luke Cage try to bend them even with his strength?

[Assistant]
The parts would probably break away from each other, but the metal itself would bend instead of breaking. Materials go through two types of deformation before breaking: elastic (like a spring being slightly stretched) where they return to the original shape, plastic (like stretching a spring waaaay out) where they will not reshape, and after this they reach their yield strength where they break. Most of the metal parts of guns would plastically deform, not yield.
Source: am engineer. Took some classes about this.


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

[User]
Did we learn anything new from this recent Venus Transit?

or did we simply observe it in ways we havent before due to scientific and technological advancements?

[Assistant]
The hubble space telescope has been used to observe the transit (by observing it's reflection off the moon).  This is being used to confirm that our models of how extrasolar planets dim the light from their sun are correct.

Technically that's not something new, but it does give us greater confidence that our models are correct.


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

[User]
Reduce inflation by reducing money supply?

Im probably being a moron but if inflation is caused by money becoming less valuable, cant the government just reduce the amount of money in circulation to make its value increase?

What if the government sold a ton of assets to the banks. The banks would pay with cash. The government would then hold onto that cash, keeping it out of circulation. Money is therefore more scarce, making the value of any unit of money increase.

Im sure there is an obvious answer to why it isnt as simple as this, but I know almost nothing about this stuff so would love to understand it if someone can ELI5. Thanks.

[Assistant]
No it's literally that simple and that's pretty much what governments do.

Or rather, they control inflation by controlling the "speed" of money creation.

Think of it like that, if you're driving a car, you don't always slam on the brakes to reduce speed, letting go of the throttle, or simply pressing the throttle down *less* can also reduce your speed depending on the circumstances.

It's the same with money creation. The central bank could slam on the brakes and halt inflation very quickly or severely, or it could also just *slow down* money creation and also reduce inflation.

That matters because creating more money causes inflation by causing an increase in aggregate demand. People have more money, people want to buy more stuff, and prices go up.

Consequently, the same goes for the other direction. If the central bank would shrink the money supply super aggressively, that would lead to a sharp fall in aggregate demand, and most likely crash the economy. The central bank doesn't want that, so it applies the throttle more gently.


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

[User]
[ROBOCOP] Does Robocop have a power source?

How does Robocop have a power source? I get the baby paste helps maintain his organic parts but how is the rest powered?

And If his brain grows old will he die? Go senile?

[Assistant] it does have a battery system of some kind since they refer to his "recharging" state a few times. How often he needs to recharge is unknown since we see him hide out in an abandoned warehouse for a while and repair his damaged parts after his first run in with ED-209 he must be able to run several days without issue.


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

[User]
What makes Immanuel Kant such a good philosopher? What did he express or mention that made him so prominent and outstanding?

He is my favorite philosopher just because people say he is one of the top 3 best, and I even have a book about him.

I am just a beginner, and a novice, and I don't really understand what makes him so great?

[Assistant]
Why is he your favorite philosopher if you don't know why he's great?

Kant is important in philosophy mainly for what he calls his "Copernican Revolution"--his idea that the mind doesn't merely record the external world, but that it actively shapes it.


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

[User]
Can flammable liquids/gases just "combust" in high temperature environments or do they require a spark or some sort of ignition/catalyst?

We touched on the combustion of organic molecules in my org chem class and I was just curious if a flammable substance is placed in a controlled environment and the temperature increases, will it eventually just ignite?
What would happen to initiate this on the molecular level (like is there a mechanism)?

[Assistant] A diesel engine operates by this principle. A fuel-air mixture is compressed until its temperature and pressure become great enough for it to ignite. What happens on a molecular level is that in order for any reaction to proceed, there is a certain energy barrier that must be overcome, and once the temperature is high enough, the molecules have enough kinetic energy to overcome that barrier.


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

[User]
CMV: High schools should have a career path option for those who aren't planning to go to college

The high school system in the US serves mainly as college prep. It's unrealistic and honestly just ridiculous to expect all high schoolers to go on to to higher education. It does not properly serve students who will be going directly into the workforce. I believe this plays a role in how many students drop out and unemployment rates for young people.

Sure, there are some trade programs you may be able to get into. The problem is there is that these programs have limited availability and only serve a handful of careers. For this reason, I am disregarding trade programs in my argument.

Here's my proposed solution:
High school would have two paths, college and career (like the game of life). Coursework would be the same for 9th and 10th grade. The usual core classes
For 11th grade, you get to choose either a college or career pathway. I feel this is the most appropriate time to allow students to make this decision. With how it is currently, students are expected to start their college search in 11th grade and have the option of dropping out.

The career path would consist of classes teaching the essential skills needed to find work and become independent. Example classes would be:
-Job searching and interviewing
-Basic computer literacy (word, excel, etc)
-budgeting and money management
-courses specific to different industries like food safety, customer service interactions, etc.
-part time employment would count as a certain amount of school credit
Some core subjects would still be required but in a form where it focuses more on real life skills, like an English class that is centered around resume writing, writing professional emails, etc.

If after a career path student graduates they change their mind and want to go to college, they still can. Plenty of students who drop out still go on to get a college degree, they just need to take some extra courses.

I feel this is the best way to prepare young people going into the workforce and increase graduation rates. But I'm sure there must be a flaw with this plan otherwise it probably would be implemented. CMV.

[Assistant]
Contrary to popular teenage belief, the vast majority of high schoolers have no clue what they want to do with their lives or at least have an unrealistic idea of how the pathway to their dreams will go.

Giving the students preparatory information for college is essentially preparing them for the tougher scenario (education-wise). It's a hell of a lot easier to take a few resume, LinkedIn, and interview workshops compared to catching up on years of high school education lost to this alternate pathway. Changing your mind and going into the workforce immediately after being prepped for college is orders of magnitude easier than someone who was never prepped for college changing their mind and wanting to go to college.

In addition, the proposed alternate course load is objectively easier and less time consuming than a traditional course load, making it very exploitable for lazy students who are just looking to breeze through while learning as little as possible. This one is more of a minor point but still something to consider.

Essentially, high schoolers should not be trusted to make such an important and long-term decision until at the very least they've graduated. We should continue to prep them for the toughest scenario (college/university) with immediate entry into the workforce being an alternate choice that can still often benefit from high school education. Let them be prepared for college and change their minds later if they want. It's a hell of a lot easier than dealing with someone years behind in education wanting to suddenly go to college.


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

[User]
ELI5:What is live ball v. dead ball baseball?

I've just gotten into baseball recently and I notice that there is often a distinction between the live ball and the dead ball era of baseball. Can somebody please explain this distinction as well as why it results in higher scoring games during live ball baseball?

[Assistant]
In the early 20th Century, baseball was played in larger ball parks, and used balls that were softer, due to the way they were made and from overuse...a single ball might be used over multiple games.  Worn balls also gave the pitchers an advantage, as scuff marks and wear damage allowed them to put more action on the ball.  This resulted in a ball that was harder to hit, and wouldn't travel as far when it was hit.  Baseball strategy that revolved more around getting base hits, and the rare home run was seen as a mistake, a fly ball that just happened to travel a little farther.

Once teams started using better balls and replaced them more frequently, batters could hit further, and strategy shifted accordingly.


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

[User] [Warhammer 40k] How do you become a High Lord of Terra?

[Assistant]
Be rich. Be influential. Be good at your job. Be old.

Basically, in order to become one of the 13 High Lords, you have to rise extremely high in the ranks of various branches of the Imperium. That requires competence, influence, and most of all... living a very long time.


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

[User] [WH40k] Are there Khornate/Nurglite/Tzeentichian Eldar?

[Assistant]
The others here are actually incorrect, though it's not something that is widely published. There ARE Chaos Eldar, and the God they favour depends on the individual. When they die, it's up to their patron to fight for their soul, but the whole point of serving Chaos is to try not to die.

Eldar Souls are exceedingly valuable to the Chaos Gods, because they basically taste the best. They remain conscious, so continue to generate emotion and experience after death, and Slaanesh's automatic claim on the overwhelming majority means the other gods relish the opportunity to nom down.

As such, in order for an Eldar to survive such an arrangement is to be very, VERY good at killing. The sheer weight of souls they send their patron has to outweigh their own value, usually by many times over. Because of this, the Eldar that survive as Champions of Chaos are amongst the most powerful and deadly. They almost always work alone or as temporary allies of others, as they have a tendency to kill everyone around them to keep their patron appeased.

The only known, named Chaos Eldar is Araha, believed to he dedicated to Khorne.


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

[User] Does crime in all countries come mostly from the economic underclass?

[Assistant]
I hope it's OK to ask a follow-up question:

If we do think that crime is mostly from lower castes, could this be because wealthier individuals are better able to conceal their criminal activities, or to avoid punishment through better legal defense capability?

Said another way, if rich people *did* commit as much crime as poor people, how would we even know?


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

[User] ELI5- Why are there unsolved mathematical equations? Who wrote them and how do they know if they are solvable or not?

[Assistant]
So...you should note that mathematical problems and mathematical equations aren't inherently the same thing.

An equation is basically just two sets of algebraic quantities that have an equal/greater than/less than sign between them. Some of these equations are inherently not solvable because they have self-contradictory answers. For example, let's say you have the equation;

1/(x + 3) + 1/(x - 3) = 6/(x^2 - 9)

You can manipulate it (multiply both sides by "(x + 3)\*(x - 3)") to get the following;

x + 3 + x - 3 = 6

or;

2\*x = 6

or;

x = 3

But that doesn't actually work, because if you plug x = 3 back into the original equation one of the two terms on the left side of the equals sign gives you a 1/0 situation, which means that x = 3 is essentially not "allowed" to be an answer. Thus, the equation has no solution, making it unsolved.

For unsolved *problems*; those are basically just mathematical statements that we can't quite figure out if they're true or not. For example, there's the Collatz Conjecture; pick a number, and then perform the following operations;

1) If it's even, divide it by 2.

2) If it's odd, multiply it by 3 and add 1.

Then feed the resulting number back in, and again, and again. Doing this, you'll (probably) end up with a repeating sequence of 4, 2, 1, 4, 2, 1, etc. No matter what your starting number is, you always seem to end up in this pattern because *eventually* you wind up with some number 2^N and the whole thing collapses.

The problem is that we can't figure out how to prove that it's explicitly true for all numbers; we can only observe that it hasn't been disproven yet, which is not good enough for mathematics. Thus, the problem is unsolved.


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

[User]
Why do GPS clocks gain 38 rather than 60 microseconds per day over clocks on the surface of the Earth?

I was under the impression that satellites could be essentially modelled as inertial reference frames in that they are in free fall and thus have no net forces, thus making time run faster for them by a factor of sqrt(1 - 2GM/r*c^2 ) as compared to an object on the surface of the Earth.  This gives me 60 microseconds per day, which seems to agree with what Wikipedia suggests (.0219 seconds per year), yet every source states that GPS satellites only gain 38 microseconds per day, not 60.

What am I missing here?  Can small satellites not actually be modelled as inertial reference frames?  If so, why?

edit: I do understand that by doing change in gravitational field, then Lorentz factor, one gets the standard 38 microseconds, but I do not understand why the two results are different.

edit 2: I think I was missing the glaring fact that time is still relative, even in inertial frames.  I do not think that it is incorrect to model a satellite as inertial, as free-fall being inertial is pretty much the whole point of the equivalence principle, but closer orbits will still run slower and this is not a contradiction.

[Assistant]
As you know, there are two effects, which go in opposite directions.

Because of the orbital motion, there is a Lorentz time dilation effect that causes time to pass more slowly GPS satellite than on Earth.

Because the gravitational field is stronger at the surface of the Earth than at the location of the satellite, there is a gravitational time dilation effect that causes time to pass more quickly at the satellite.

You cannot model the satellite as being in an inertial reference frame, because its orbit is not at constant velocity; it is accelerating due to its changing direction of motion.


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

[User] ELI5: Why do some really popular reddit posts suddenly lose thousands of upvotes?

[Assistant] There's an algorithm in place to equalize stupidly high karma scores; i imagine the intent is to prevent hugely popular posts from dominating the front page for more than a few hours. gotta keep the content cycling.


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

[User]
[DC] How can anyone with anything remotely resembling human limitations challenge the Flash in any way?

He can move faster than the speed of light and his reaction speed is less than an attosecond.

Captain Boomerang is a normal human with normal human limitations throwing gimmicky boomerangs. How does Flash not have him disarmed and tied up before CB even realizes that he entered the room?

[Assistant]
Because the flash doesn't use his full power all of the time. He go easy on normal humans because he doesn't want to harm seriously or kill them.

He recognise that most of his enemies are mentally ill peoples who need help more that being punched in the face and trown in jail.

And its worth noting that a lot of the Flash enemies do respect him. And the OG enemies of the Flash try to kill as few as possible , they even disaprove the newer and more violent Bad guys.

Basically the Flash is chill and his bad guys are too as a result.


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

[User] Eli5: why is it so hard to get an accurate weight when using one leg on a scale? Shouldn't all your weight be going straight to that 1 foot?

[Assistant]
Scales don't measure weight, they measure force. When something isn't moving (and therefore isn't exerting any forces other than gravity), you can use a scale to measure its weight. The same holds if you stand still on a scale with both feet, because you can get your center of gravity into a stable position and then stop moving. You could also sit on the scale to achieve a similar effect.

But standing on one leg is different. This is an unstable position, and so you constantly have to shift and exert force to stay upright. Those forces, or at least the downward portions of them, register on the scale in addition to your weight, and so the scale's reading shifts around as you do.


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

[User]
[Warhammer 40k] How do psykers work?

So anyone with strong souls or emotions whatever(specifically unlike the Tau) contributes to the Warp, which, as I understand it, is basically a sewer for psychic energy. Would that be right?

So do psykers tap into the Warp and channel it, or do they create the Warp energy they use themselves? What would happen to the average trained psyker who found himself in a universe without the Warp? What about the Emperor himself?

[Assistant]
All living things (even the Tau) have a sort of 2-way connection with the Warp, referred to by Imperial Scholars as an Animus. This 'tether' links the physical body with the Warp, and develops over time along with the biological and chemical responses of the individual, reflecting their identity, personality and emotions. It is, accurately, described as a Soul, and slowly bleeds 'thought and emotion' out into the surrounding Warp. Upon biological death, this tether is severed and the Soul is released into the Warp, where it eventually disperses and fades into the background.

In this way, living things 'power' the warp. The influence their thoughts and emotions has causes ripples in the background of the Warp, coalescing into strong energy currents and interactions. It's not that they collect Psychic energy, they CREATE it. Without living things, the Warp is calm and static. With living things, it is an infinite source of power.

The strength of this connection varies, but all living things have one. Even the Tau have connections, though theirs is considerably weaker than, say, Humans, who are themselves far weaker than Eldar. The strongest connections aren't necessarily Psykers, though all Psykers have a strong connection.

Psykers are different than normal entities in that some quirk of their biology allows them to draw power along these connections, opening miniature warp-rifts and channelling the Warp Energy through their own brains and bodies. Again, this is a biological process, and a lobotomy can actually sever a Psyker from the Warp (it's actually an extreme punishment considered a living death to the Eldar). Whatever quirk they have, the process allows them to harness and control Warp Energies, allowing them to influence the physical universe while basically ignoring it's laws.

Those who lack this biological quirk CAN gain similar powers, however, if they are able to communicate with the things that dwell within the Warp. Though certain sorcerous practices, individuals can make deals with Daemons of various sorts who can either lend them their own power (by feeding it along that inherent 2-way connection) or force open that tether to unlock the individuals own potential. This is insanely dangerous however.

If a Psyker were to be disconnected from the Warp, in any way, it would not kill them. However, they are said to experience a deep depression and feeling of detachment. Amongst the Eldar, such individuals often experience suicidal tendencies.

The Emperor would, probably, suffer from a far worse fate. His immortality, knowledge and cosmic perspective is entirely because his Animus is formed of thousands of Psykers. Without the Warp, that connection doesn't exist, and he becomes a normal man. No Immortality, no Magical Powers, no Super Strength, and no special memories.


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

[User] ELI5: What is Chemotherapy, and what happens during it?

[Assistant] it's chemical treatment to combat (usually) cancer growth.  most are in liquid form and are administered intravenously (through a drip in your arm).  a single treatment of chemo may involve receiving several different chemicals in one session, commonly over quite a while (an hour or more).  usually you sit on the ward with others while receiving it or there are some you can receive at home.  depending on the length of course this may be done weekly or fortnightly for several months.  on ward most people chat / read / watch tv while receiving treatment. the combination of chemicals are designed to slow down cell reproduction in your body.   others are designed to kill cancer cells or types of cell in your body.  there are lots of different kinds of chemo for lots of different kinds of cancer.  the side effects usually stem from the slowing cell growth and killing of certain cells : hair loss, nausea/vomiting, constipation, thirst and so on.  it's common to have additional courses of medicine that combat the side effects specifically.


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

[User] [TheCulture] Culture humans use genetically modified bacteria to control their biology, why is that better than achieving the same thing via nano tech?

[Assistant]
GM bacteria *are* nanotech, they're just 3D electromechanical, water-based, chemical difference engines... that self repair and reproduce.

Literally, they're nanotech that's carbon based, not silicon based.

Earth Humans have a very intimite (and still poorly understood) relationship with their microbiome.  Everything, from your taste in foods to sexual partners, is influenced by your microbiome - to the extent that if we just replaced yours with silicon nanobots it would be the equivalent of replacing a part of your brain with silicon - doable, but is it still *you*?

The Culture decided to go via the microbiome route and not the 'nanobiome' route - possibly for the philisophical reasons, but also because you'll never actually escape bacteria (every human race they contact will have them, every flake of dust, every surface they touch...) so might as well roll with it and make it part of the plan, not a problem.


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

[User]
I believe that lowering the US drinking age to 18 is a terrible idea. CMV.

Personally, I feel that there are many good reasons for maintaining the US drinking age of 21. It is completely normal for a society to set age limits on certain activities that minors are not considered responsible enough to engage in (why else do we have a driving age and an age of consent?); the age of 21 for drinking is not arbitrary (it was created to reduce the frequency of alcohol-related traffic fatalities) and lowering it could result in widespread social consequences (such as higher rates of youth binge drinking and alcoholism.)

CMV.

[Assistant]
One reason is simply because people are adults well before they're 21.  You can be trusted to take out a loan, live alone, and fight in a war before you're allowed to drink.  It makes the drinking age seem like pointless bureaucracy compared to those.

However, the primary reason might be that binge drinking tends to reduce when it is legal. College students and some high school students drink either way, but they tend to drink more when it isn't allowed.


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

[User] ELI5- why do screens/lights flicker in videos taken by phone or even yt vids, but not in movies and professional productions?

[Assistant] Professionals use synchronized cameras, or simply replace the screen displays in post-production with CGI. Professional cameras have lots of adjustments, like longer exposure times, that can give cinematographers more options to capture displays.


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

[User] ELI5: If we perceive sound because of vibrations, why aren't bugs/insects deterred by loud vehicles, construction sites, and other noises that are loud for humans?

[Assistant]
They don't have ears that resemble ours with a sensitive membrane, tiny hairs, and impossibly small bones that resonate.

Their membranes are cruder. Or they hear with an organ on their antenna, etc.

Loud noises don't damage them the way they do us.


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

[User]
[Fallout 3] How come wastelanders can survive multiple bullet wounds to the head?

And not just survive, but are still able to fight without flinching after taking more than one point-blank shot to the face.

[Assistant] Pre-war ammunition has mostly suffered from decay and the stuff manufactured more recently uses easy-to-make but low powered propellants. This means that bullet velocities are much lower than the original gun manufacturers expected and so they are not reliably able to penetrate the human skull with the small rounds they use.


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

[User] ELI5: Why does consuming water hydrate your skin, but putting water frequently on your skin dry it out?

[Assistant]
The thing that keeps your skin "moist" and supple is actually the naturally occuring oils that your skin produces.

If you bathe too much or use harsh soaps or maybe alcohol cleansers, these remove the oils from your skin. Whatever water is in your skin then evaporates = dry skin.

Thats what moisturizing cremes do. They not only add more water back to your skin, but they also add natural oils to keep the water in.


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

[User]
Why does adding or removing an electron from an atom completely alter its fundamental properties?

I understand why alkali metals are highly reactive, I understand why Noble gases just chill and I have a basic understanding of why some elements are radioactive or have magnetic properties but let me take Gold (please!):

It's a solid, very dense but the most malleable of the metals, has a melting point of 1064 degrees, a latticed crystal structure and is yellow.   Now if we remove an electron, it becomes platinum, an even denser white silver element with a melting point 700 degrees higher and a cubic crystal structure.  If we add an electron it becomes Mercury with a super low melting point of -39 degrees and a rhombohedral structure.  Add a few more and it becomes poisonous (lead), then turns into a metalloid (Polonium) and then a non-metal (Astatine) all with completely different fundamental properties.

So what's the story here?

Edit: I'm an idiot; the atomic number is of course the proton number.  Don't know what I was thinking.  Still, the question remains.

[Assistant]
>Now if we remove an electron, it becomes platinum

no, it does not. it becomes Au^+1 (gold atom with a charge on it). if you removed a *proton* it would become platinum. and even then, it would be an isotope of platinum, you would have to remove another neutron and electron to get a normal platinum atom.


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

[User]
Why didn't the big bang turn into a black hole instead of an explosion?

Me and my dad were talking about when all the matter was in one place why didn't it become a black hole instead of the big bang? So we couldn't find an anwser so I thought why don't we ask Reddit?
Oh and btw what is the density of the matter in a black hole and is that the highest density possible?
Hope you understand what I have wrote and sorry for any grammar mistakes, I'm not the best at english :)

[Assistant]
First, you need to understand what exactly is the big bang.

The big bang is not a "big explosion of matter", as you might picture. Think about larger scales, bigger than galaxies or clusters of galaxies or everything you can picture. Matter is more or less homogeneous and you can treat it like a fluid (like a lake, for instance. from far away, it looks homogeneous, but if you get close, you'll see molecules and atoms and everything).

Whenever you have such a homogeneous fluid and you turn on gravity, you find out that it is dynamical. It will either expand or contract, depending on what is the total energy of the fluid. When we look around, we see that this is what happening: everything is expanding. So we have a good estimate for the density of this fluid around us. Keep im mind that in the effective cosmological description that we have, this "universe" has an infinite volume, so expanding and contracting are terms that are related to how you measure distances.

When you switch back time, though, it means that at some point the density will be bigger and bigger and bigger. You find out that you will undergo phase transitions (for instance, at some point in the past all the matter was radiation, and before that it was some other strange fluid with different properties).

This is the big bang: it's not a statement about what was the state of the universe when t->0, but how the universe has evolved ever since. When you try to understand what happens at t->0 you get a singularity, but that's not physical, since at this point you can no longer treat all your matter content as some homogeneous fluid. We say that the "effective theory breaks down", which literally means that you can no longer trust whatever approximation you made to derive this "big bang solution".

So what you are saying is right: if you compress a fluid such that its energy density is high enough, it will form a black-hole. And certainly there might be primordial black-holes around because at some points, the energy density might become a lot bigger through some thermal fluctuations and you might just pop a black-hole. But taking the universe as a whole, you can NEVER have the whole energy content to become larger than this cutoff, which is given by the Planck energy scale, otherwise, bam, your effective description is breaking down.


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

[User] [Community] Who *was* the Ass Crack Bandit?

[Assistant]
Don't you mean who *is* the Ass Crack Bandit?

Allegedly it was Alex "Starburns" Osbourne, however he later recanted his confession. Also he's not a Dave fan so, you know, he doesn't fit the profile. Who knows who the ACB really is?


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

[User] ELI5: Why electrons do not interact/get affected with strong force?

[Assistant]
The four elementary forces can each only interact with particles that have particular properties. The gravitational force works on objects that have mass (it should work on individual particles with mass but we mostly see it on big objects because the force isn't that strong). The electomagnetic force works on anything with an electric charge. The strong nuclear force works on anything with a "color charge". Finally, the weak nuclear force works on anything with a "weak isospin".

Electrons have mass, charge, and weak isospin, but no color charge. Thus they will be affected by the gravitational, electromagnetic, and weak nuclear forces, but not the strong nuclear force. In the same vein, neutrons have no charge, so they won't be affected by the electromagnetic force.

So far the only particles with color charge we know of are quarks, and they are classified as "red", "blue", and "green" just like electric charges can be positive or negative. There's also "anti-red", "anti-blue", and "anti-green" for antiparticles. Just like positive and negative charges attract each other, color charges like to be neutral, either sticking together a color and it's anti-color for two particle systems, or all three colors together in three particle systems.


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

[User]
CMV: Twitter's Hypothetical Fact-Checking Program is a Terrible Idea

There have been a few various Reddit posts and news articles, and I fully admit that this entire thing, at the moment, is really a non-story; Twitter had created design mockups (likely not even functional yet) as to how they'd designate posts that provide what they designate as "harmfully misleading" information. Twitter users, likely prolific public figures, would recieve an orange or red label based on the verity of whatever statement they squeeze into 240 characters.

So, this argument moreso falls along the idea that, if implemented, this would be an awful idea.

I will admit that, of course, the idea of this project is well-intentioned: Twitter is one of the largest social media platforms and regularly gives people (yes, even famous people and presidents) the ability to mass-spread misinformation.

I will not argue that misinformation is harmful, to a degree.

However, Twitter seeking to easily identify and place warnings on such tweets would be bad for a myriad of reasons, and I'll list them below.

1. Most obviously, who gets to decide what's truth? Assuming Twitter is labelling tweets as true or false, they have to have some form of information backing these statements. If you're going to specify something as objectively false, you need a source, which becomes murkier when a claim isn't totally backed by just one source. If Trump makes a claim and says Study A supports that claim, could Twitter find Study B that came to a different conclusion and say it's false?

2. Is "truth" only determined by statistics or by a larger narrative? Facts can be objectively "true" and  may not necessarily add to the greater picture or support a false bigger picture. For example, there is a well-known and oft-parroted (by the alt-right or other white supremacists) statistic that states that the black population, a minority of the united states, commits nearly fifty percent of the crimes. This implies that african americans are more prone to crime in general. However, if we look at these statistics- which are usually supported by government studies- we see that this only accounts for the actual charges, not taking into account how often black youth are charged for crimes they didn't commit. It also doesn't take into account that poor, urban areas usually result in an increased crime rate regardless of ethnic makeup of said urban areas. So while it's "technically true," it's being used to dogwhistle a racist narrative (blacks are prone to crime). But if Trump tweeted "...you know, thirteen percent of the population commits fifty percent of the crimes," how would Twitter regard this statement, assuming it is the only one made in that tweet? If Twitter denied that statement, it would be ignoring government data. If Twitter supported that statement, it would be enabling racists everywhere that their beliefs are true.

3. Certain "studies" aren't always truthful in their own decision-making. Consider the also oft-cited study of how nearly forty-percent of police officers in the United States are domestic abusers or whose spouses have experienced "spousal abuse." Regardless of your personal opinion on policing in the U.S., the study was conducted under certain pretenses, that included "shouting" at your partner as "spousal abuse." Due to this inclusion, the numbers of the study are inflated, which some see as misleading in it's representation (most people, as well as the law, assume domestic abuse is physical.) But really, you could do the same for any survey or study; assume a politician wants to point out the success rate of a political strategy, and points to a study where other countries who've done A + B get C, our desired outcome. The study could easily fail to mention that said countries have D, E, and F in place to make A +B work; but since a study says "yes, that's true, in these countries A + B = C" then the claim, based on that source, is correct. Another study could come out and contradict those findings by adding the additional information. Which would twitter decide is fact?

4. Trying to argue against social media's influence on communication and information would be silly at this point. It's ingrained itself in our politics, our culture and our popular discourse. But we shouldn't allow it any more power to discern what we see as the truth. If an anti-vaxxer states explicit lies on a platform, then it's up to you, as a viewer, to base your decision on your own findings. Of course, anti-vaxx methods being disproven is only a google search away. Where this gets sticky are the claims that aren't easily proven or disproven. Once again, you'd need to look into it yourself; trusting Twitter's binary response of "yes or no" on a fact contributes to intellectual laziness. "Oh, twitter said it was true (without providing details) so I guess it's true."

5. We already have other third-party (in this case, not Twitter or the claim-maker) fact-checking websites available for everyone to see, like Snopes or Politifact. Even these reputable sources are labeled as "biased" by their opponents on both sides of the political sprectrum. While these sources usually provide a simplistic way of understanding (Snopes via their "mostly true/false" and Politifact's "pants on fire meter" they often make more than just that binary claim of wrong/right. They'll explain the claim, the scope of the situation, the facts and any other circumstances or context, and then why they based their judgement as such. Even if these services made a false or faulty judgement, the process of their decision-making is explained, so they can always be held accountable if they make a mistake. With a simplistic "wrong/right" indication for Twitter and nothing else, we have no way to understand how Twitter comes to their conclusions or if they did so in a manner that avoids mistakes. It'd be nearly impossible for a fact-checking source to be unbiased; if we can get their reasoning, however, we can better understand the situation without relying solely on the opinion of others to guide us.

6. I'm not trying to argue that all fact-checking is wrong: I just believe that Twitter should remain the plaform, not the arbiter, of the information that it disseminates. Do I have a better idea on how to stop misinformation online? No. But I don't believe that an influential company becoming the arbiter of truth in the digital age is the solution, or even a solution, that could do more good than harm.

So, CMV?

[Assistant]
" ... Indeed it has been said that democracy is the worst form of Government except for all those other forms that have been tried from time to time. ..." - Winston Churchill

The salient question isn't whether a fact-checking program like that has drawbacks.  The question is whether it's better or worse than the status quo or some other alternative.   So just looking at the shortcomings is looking at half the picture.   How does this new scheme compare to whatever twitter is already doing where there is clearly one set of rules for famous and powerful people, and another set for normals?

Similarly, something can be "good for twitter" even if it isn't good for you.  The fact is that twitter doesn't really care whether people use the service to publish dangerous bullshit.  To me it seems like this 'fact checking' stuff is part of an effort to avoid more stringent or onerous government interference.


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

[User]
What happens at a chemical level when a bottle of liquor is allowed to "rest"?

I'm curious about this and don't really see it addressed elsewhere.  It's become common to allow a bottle of liquor (whisky, cognac, etc) to "rest" after opening.  In fact, I just read this in a vodka review: "It isBelugas philosophy to have this vodka rest after each step of the production," explains Borisov. After a five-time filtration process to achieve maximum smoothness, the vodka's final resting period is 90 days. "This allowsitto reach perfect balance and harmony,"

Since I always like to ask myself "why is that" and "what mechanism is at work here", I'm asking precisely that.  Is there some chemical change happening to drive a flavor shift or is this "resting" of a seemingly stable substance mostly psychological in nature.  If a sealed or capped bottled is allowed to "rest" sans additional oxygen or heat, how is it changing?

[Assistant]
With a lot of spirits, their individual character comes from the infusion of other flavors based on what vessel they're resting in. Bourbon, for example, uses oak barrels that are charred on the inside. As they rest in large barns that are not temperature controlled, the natural thermal expansion and contraction causes the spirit to move in and out of the barrel wood, absorbing various organics and other chemicals along the way.

Once bottled, spirits don't age anymore. Ideally. If they're poorly sealed, then they may oxidize.

Resting a bottle after opening will allow for any volatiles that want to escape to do so, although in a narrow bottle your available surface area is limited. That's usually why you decant into a different container from the bottle before drinking.

Any flavors remaining in the spirit after it rests are what 'should' be there.

Vodka is a bit silly though, as it's generally going to be as close to straight ethanol and water as you can get.


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

[User] Eli5: Why is Urban warfare feared as the most difficult form of warfare for a military to conduct?

[Assistant] There are way more places to hide people, traps, and weapons. You have to search every room in every building on every street. Plus, there's the constant danger of civilians being caught in crossfire or combatants disguising themselves as civilians. Much harder than facing another uniformed group on natural terrain.


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

[User]
ELI5: Why does it seem like all Caribbean islands (Jamaica, Bahamas, Bermuda, Puerto Rico, etc.) seem to be third world countries, with terrible economies and infrastructure?

This is not meant to offend anyone from these countries, its just the impression I get being American.

Someone I know just got back from a service trip to Jamaica to teach first aid and CPR to villagers and describes a place where everyone is poor, and there are no jobs and no place to go.

Are there any particular reasons, historical or otherwise, for this trend? I have been to Bermuda and the Bahamas and even in the high traffic tourism areas you can tell how poor the people are and how sadly hopeless their situations seem.

[Assistant]
Historical and geographical reasons.

Most of those islands were colonized by Spain in the 16th and 17th century and used to produce sugar and tropical fruit crops.  The colonial government had little interest in improving infrastructure, education, or standard of living and many of the residents were slaves.

When the Spanish empire started to unravel those islands found themselves suddenly self-governing with little experience or resources.

Since then they've struggled with corrupt governments, meddling from cold war superpowers, and the simple lack of resources on an island.


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

[User]
[DC] I just killed the world famous reporter Lois lane by accident. How screwed am I?

Me and my friends were joyriding in metropolis and idk all the details cause everything happened so fast, but we hit some lady by accident. We checked if she was alive but nothing. She was wearing a daily plant badge and we saw it was that famous lady that interviews superman all the time. We left the body and me and my friends have been hiding out in different places since. We have no idea what to do or where to go. How is superman going to handle this?

[Assistant]
I think everyone is overlooking a very important factor.

Yes, Superman is a Good Person™ and probably won't chuck the moon at you or anything.

But you know who's Superman's best friend, and *really* sensitive about loved ones getting killed?

The Bat.

I hope you've got good health insurance, because your vertebrae are about to turn into a pile of gravel.


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

[User] ELI5: How come my 4y old remembers last years christmas very well. And remembers everything we did last summer. And I dont remember anything from my first 4 years? Cant be the years cause a 60y old remembers his high school pretty well.

[Assistant]
Because those are practically the only memories they have.

The last year or so have been filled with 'firsts' the only experiences they have had. So of course they would be worth remembering.

By the time you are older, you will have experienced those 3-4year old memories dozens, if not hundreds of times, and most of them will have been better, or more memorable than the ones that happened when you were 3.


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

[User] ELI5: What is Sharia Law and why is their so much controversy with it?

[Assistant]
Sharia means 'legislation' in Arabic and is basically the "law of Islam", when a society has the Quran and the teachings of the prophet Muhammad as their law, you could say the country has 'sharia law'. So basically, it's islamic theocracy. So a judge in a country with sharia law would be someone who is an expert in islamic vice and virtue.

I suppose the controversy surrounding it is first and foremost that theocracy is viewed as an old and dated way of rule (here in the west at least).

There is also a general fear of anything 'muslim' in western society today, which is probably part of the explanation as well.


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

[User]
[Star Wars] Since the Kaminoans and the Trade Federation were both able to create large armies that the Republic and the Jedi were unaware of for over a decade, did the empire ever do anything to prevent this from happening again in the future?

Or is the galaxy just so large that it's nearly impossible anyway? If you think about it, the kaminoans/Trade Federation could have conquered the galaxy, had the sith not been involved.

[Assistant]
In Legends, both the Kaminoans and members of the Trade Federation built new armies after the Clone Wars, and both were swiftly dismantled by the new Galactic Empire.

In canon, The Empire's biggest weapon in preventing uprising was fear of reprisal. The built really big spaceships with really big guns and mercilessly slaughtered anyone who even remotely tried to fight back. After a certain point, it's easier to just live under the Empire's boot than risk being stomped.

Also, you have to realize how much effort went into the Clone Wars the first time around. Palpatine had both armies built in secret, by proxy. Then he actively distracted the Jedi with other matters, (and tied up the Republic by bureaucracy) until he was ready for the war to begin.


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

[User] [General Fantasy] Why don't wizards shave?

[Assistant] In general, they get too focused and distracted by their studies to take time to shave. The basic hygiene spells that they use to get around having to waste time on bathing don't trim beards. So... after a while, most male wizards end up bearded. Now, it's become a bit of a meme, and wizards compete over beard length when they have conferences or meetings.


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

[User] [Marvel] Taskmaster has a photoreflexive memory that allows him to copy any technique by seeing it only once, and learn other certain skills with mere exposure. If he received tutoring by, say, Doctor Strange, would he be able to master magic extremely fast and become a phenomenal Sorcerer?

[Assistant] He'd master the physical side very quickly but there's a mental side that's much more important. When you make a shield for example, you aren't just gesturing with your arms. You're also feeling the energy flow through you and imagining it form different shapes. There's also a lot of book learning involved -- you have to understand the forces you're manipulating.


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

[User]
[Elden Ring]Is player deaths in Elden Ring canon like other from software games and if yes then what is the reason for our respawn abilities.

Most from software games consider every death as canon and have an explanation about how we come back. Is this true for Elden Ring as well and if so how does that work in this world.

[Assistant]
Here's the fun thing: in Elden ring, *nobody* dies permanently. The concept of permanent death was almost completely destroyed when the Elden Ring was shattered. Even the characters that otherwise stay dead for the duration of the game (bosses, mostly) would come back eventually given enough time.

The one exception to this is the rune of death, given to the Black Knives. They actually can kill people permanently (whether or not the black knife assassins you face in game have this ability is unclear).


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

[User]
ELI5: How does the brain store words in multiple languages

I'm bilingual and currently working on my third language, so I've been curious as to how the mind associates things in multiple languages.

[Assistant]
This one's quite interesting since we don't really know how the brain stores words in one language in the first place, but our current best guess is that they are stored in a mental lexicon which is like a spider web connecting different words of same categories, be it word type, semantics, same prefixes, suffixes etc.

There are two theories regarding multiple languages: either your brain just stores concepts and links them to the words in both languages, or you have two of those webs which additionally are connected to each other via translations.


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

[User]
ELI5: Why does eating something hot (like a ghost pepper) make humans actually produce heat?

Why does eating something very spicy make humans actually give off heat?

Example:  When I eat something like ghost pepper based hot sauce, I radiate heat off the top of my head.

[Assistant]
You're not radiating heat. Not in the way you think.

Capsaicin is causing an inflammatory reaction in your body, starting with your mouth. Blood is rushing to that area. *That* heats up the area, not the peppers. But your overall body temperature didn't really change. You're just perceiving your normal temperature in a different way than before.


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

[User]
[General Superheroes] Quipping and poking fun seem to be incredibly effective against supervillains. Why don't more superheroes do it?

Spider-Man is a well-known example; he uses quips and alternative ways to mess with his opponent, which proves to be highly effective. Why don't other superheroes, e.g. like Superman and Captain America, use this strategy?

[Assistant]
It's actually more difficult than you think to be a smart arse in the heat of the moment. Parker does it as a coping mechanism because of the stress of it and it just so happens to be his forte.

Captain America doesn't want to be known as the guy who tried to drop a burn and ended up stammering about the dudes gloves.


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

[User]
How do attractive forces actually work?

For example gravity, magnetism and electrostatic. Do particles pull towards each other by some link like an elastic band or do they emit particles in the opposite direction to each other to push them together (if so how do they know to do that?) or is it something else entirely?

[Assistant] It seems you are being confused by considering virtual particles as being anything at all like actual particles. They are not. Thinking of virtual particles like this is nice for being able to draw Feynman diagrams but not really for anything else.


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

[User]
I do not believe it matters whether or not there is a God or gods. CMV.

**EDIT:** First, thanks all for participating. Second, thanks for 57 upvotes - I'm glad this is a successful post. Third, I stopped replying because I was noticing all the same arguments and none of them have changed my view in any way. I remain apathetic as to the (non)existence of a supernatural creator.

This is not about the BELIEF in a supernatural creator. That can be a deep and profound and meaningful personal journey. I personally find it to be bullshit, but that's not the point. My point is you can believe or not believe and it doesn't change the world or the fact that god may or may not exist.

The argument that it matters because prayers could then be worthwhile is false: Prayer has no measurable effect. Whether or not there is a god, prayer has the same effect.

The argument about an afterlife is also false: The existence of an afterlife does not depend on a god *but* if it *did* a hell is better than nonexistence. Therefore it only matters if you fear hell, which I do not. Frankly I think all Christians feel the same way because Christian doctrine is basically engineered to ensure that everyone goes to hell.

The argument that it matters if god can intervene in human affairs is similarly missing the point: If god exists then (s)he has always existed and therefore the earth and universe spins the way it does, period. Sure (s)he could do whatever but (s)he doesn't. Worrying about god because (s)he *could* send dragons / typhoons / miracles is kind of like worrying about blackholes and aliens and the center of the earth boiling out to the middle.

In other words and to put it simply the earth and universe have and will continue to move in predictable and reliable ways irrelevant of the (non)existence of god(s). If there's an afterlife then there is, if there isn't then there isn't. It is what it is.
---
===

**ORIGINAL POST:**Since it is impossible to comprehensively disprove or prove the (non)existence of a deity or pantheon I feel it's better to just get on with life and accept that the world is at it is and will be as it will be and the afterlife, if there is one, will be as it will be. Whether or not it's all been arranged by a theoretical superbeing / creator is irrelevant to our present situation.

To be clear, I do not believe in god. I was raised Jewish and identify as a Jew and if I were to be religious that's the sort of view I'd take, but I no more believe in god than I do in unicorns and place the same importance on the lot of supernatural creatures.

Whether or not there is a god:

* The world / universe assumes orderliness.
* Good things happen to bad people and vice versa.
* People are capable of being benevolent or malevolent irrelevant of (or because of) their spiritual beliefs.

Why should anyone care whether or not there is a god or gods? I do **not** ask why we should care whether other people believe, as the answer there is clear: Atheists find religion harmful and theists find conversion to be a holy mandate.

**edit:** I am not arguing that BELIEF in god is irrelevant because it can have a major impact on one's life. I am saying irrelevant of belief god's existence is irrelevant.

[Assistant] It matters if there is a god who rewards belief, and the only way to win the prize of an afterlife (or of a super-special-good afterlife) is based on the amount of devotion toward him/her/it/them you have paid during your life.


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

[User] ELI5:Why can't men (easily) continue with intercourse after orgasm? And why women can?

[Assistant] A man who continues to have sex after orgasm runs the risk of scooping out all of his own semen, undoing his hard work. There is an evolutionary advantage to letting everything cool down for a little while.


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

[User] [Witcher] Are there giant sea monsters (Kraken)? How do witchers handle them?

[Assistant]
For a kraken, or really most giant sea monsters, the procedure is as follows:

**Step One:** Hire out a barge and the biggest galleon you can lay hands on to tow it. Don't plan on getting your deposit back for that barge.

**Step Two:** Load down the barge with whatever farm animal is cheapest that week. Kraken aren't picky.

**Step Three:** Have your hired galleon haul your loaded barge, with you on it, into the beast's territory under the light of a full moon.

**Step Four:** While en route, take two swigs of *Yuri's Cloaca*. For the uninitiated, it's a potion that, among other things, dramatically increases the amount of oxygen that can be safely stored in the blood, allowing a Witcher to fight for hours without drawing a breath.

The name came about because Yuri, the Witcher who invented it, kept it a secret and so a rumor started up that the reason he could hold his breath for so long was that he was down there sucking air out of fish assholes.

Plus the taste is just awful, even by potion standards.

**Step Five:**Instruct the crew of your galleon to circle your barge about a mile away, and to run dark. Light torches around the barge and slaughter an animal or two, letting their blood drip into the water.

**Step Six:** You now smell delicious and are impossible to miss. You'll probably get a questing tentacle within minutes. Let it have the run of the barge. Once your prey determines that, holy shit, there really *is* a boat full of easy meat up there, it will fully emerge and ensnare the barge.

**Step Seven:** Now you've got him! While the Kraken is busy trying to crush the barge launch yourself as close to its center of mass as you can get, while avoiding things like teeth or spikes.

**Step Eight:** Start digging. You want to become the deadliest tick there ever was. A combination of katar and hook sword will usually serve you well here.

The way these monsters are built, they can't easily respond to something that's sitting right on them, and their flesh won't be heavily armored so you should be able to worm your way into its body and fully out of its reach.

**Step Nine:** Here's where the wisdom of doing so much of your anatomy training blindfolded becomes apparent. You're going to have to find what passes for a central nervous and/or circulatory system and deliver a killing blow, and do it quickly. There's a good chance your prey is freaking out right now and will dive for safety.

Diving is bad. A monster that dies underwater can't be roped by your pursuit galleon, and that means you won't have a carcass to bring back for proof of your kill.

**Step Ten:** Assuming you moved fast enough, you should now have one giant sea monster corpse ready to be redeemed for a substantial reward, minus the barge deposit of course.

**Step Eleven:** Get back to your ale and whores until something else needs killing.


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

[User] eli5: How were square roots calculated in the first place, before calculators?

[Assistant]
You would look them up in a table. The tables were populated by hand calculation.

For example, what's the square root of 20? Well, you know it's going to be more than 4 and less than 5, because 16 is 4 and 25 is 5. So you might try 4.5. So then you would square 4.5 and get 20.25. This tells you that the square root of 20 must be a bit less than 4.5. So you could try 4.4. You square 4.4 and you get 19.36.

So now you know that the square root of 20 must be 4.4xxx. So you might try 4.45. 4.45 is 19.8025, so that's too low. 4.46 is 19.8916, so that's too low. 4.47 is 19.9809.

That gives us a second decimal place. Now let's add another decimal place. 4.475 is 20.025625. 4.474 is 20.016676. 4.472 is 19.998784...

So now by essentially guessing and checking, we've gotten three decimal places on the square root of 20. 4.472. We could keep going and keep adding decimal places through the exact same method.


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

[User]
[LotR] How do the stone giants reproduce?

Great big stone sex?

[Assistant]
It's questionable whether the stone giants even *exist*. The original text of the Red Book mentions them "playing" by throwing stones at each other as a way of explaining loud, thunderous sounds during a rainstorm. It's entirely possible that this was a whimsical addition by Bilbo.

If they *are* real, then the giants are most likely rock animated by some sort of spirit, or descendents of such creatures. If so, then their procreation could be done via any of a dozen different methods -- they could craft children out of stone, or new giants could spontaneously form from spirits entering a cliff face, or they could have some weird form of sexual reproduction. There's simply not enough evidence to say how they reproduced (which should be clear from the fact that it's unclear if they actually *exist*).


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

[User] [Star Trek] Why does Starfleet insist on putting the bridge on the most venerable part of the ship, namely the very top deck and dead centre. One phaser strike and the whole command staff are gone in one go, wouldn't it be better to you know have it 50 decks lower and not in the saucer at all?

[Assistant]
For one, it's not all that vulnerable.  It's still behind shields that take an ungodly amount of destructive force to breach.  Not an unimaginable amount, but it's really quite a lot.  To boot, once the shields are gone, no part of the ship is really that much safer than any other.
And building on that, for two: Starfleet isn't in the business of getting in fights.  It's not a Navy, and their ships, with a few notable exceptions, aren't built for war.  Given those strong shields, the only conceivable need to bury the bridge deep in the bowels of the ship is that you're trying to fight people with very powerful weapons.  This is a failure mode for the Federation, not a primary operating stance.  Thus it's not something that's going to be a primary motivation in starship design.


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

[User] [Star Trek] How can a holographic bullet kill somebody on the holodeck? How can a holodeck misfuction so much that it creates a being that can then leave the facility ala Prof Moriarty?

[Assistant]
The Holodeck creates "hard light". If you can use the Holodeck to create a chair that you can sit on, then you can create a bat to hit someone upside the head. Or a bullet.

Further, spoiler here, but Moriarty never left the Holosuite program. He left a simulation of it, and walked onto a simulation of the Enterprise outside the Holodeck.


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

[User]
[MONSTERS INC] I would love it if someone could please analyze the curriculum of scaring and how it could be tied to Waternoose's concerns with the future of scream energy. The new scarers, energy crisis, the "risks" and stresses of being a scarer, and the issues trying to find a good scarer

I would also love some theories and lore that most people would not know about the world of monsters inc.

[Assistant] Well, according to the History of the Monster World bonus DVD feature, monsters evolved from a race of prehumans called Mons some tens of thousands of years ago, and, chased off by early Homo sapiens, sought refuge on an enchanted island (on which Monstropolis was presumably built). Ingesting the strange fruits of this island turned them into the strange otherworldly creatures they are now.


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

[User] eli5: Why is candle wax transparent when its hot and opaque when its cool?

[Assistant] When wax is cool, it's crystallized.  These wax crystals can scatter light so it doesn't reach your eyes, so the crystals are opaque.  When hot, the wax molecules are all loose and free, and can't scatter light.  That means the light goes straight through, making the liquid wax look transparent.


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

[User]
CMV: The constant focus on groups or classes labeled as minority only exacerbates the ill effects of prejudice and discrimination.

Acknowledging, celebrating, or otherwise reinforcing the perception that a particular group is a minority and/or otherwise disadvantaged, however well-intentioned, is counterproductive to the intended goal of realizing equality.

Those in the minority group are inclined to consider themselves disadvantaged which inevitably leads to the emotional response to "fight" for equality.  Similarly, those that do not belong to the minority group are influenced - even motivated to falsely consider themselves superior thus leading to an emotional response of keeping "them" in their place.

There most certainly are groups of us that are disadvantaged and discriminated against in society today, whether that is based on religion, color of our skin, sexual orientation, etc.

The real question is: How do we stop perpetuating the idea of "us vs. them" when there is so much emphasis on celebrating the diversity/differences between us, who, after all are all just humans on a rock flying through space.

[Assistant] I think your point us clearly refuted by the relatively recent achievements in the Gay Rights movement and their attaining the equal right to marriage.  This did not come about by some benevolent move by the establishment after years of respectful silence by homosexuals and those who supported them.  This right was given after years of focused activism.


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

[User]
What do professors/postdocs look for in undergrad students wanting to volunteer in their lab?

Are there any particular qualities they look for? I've been told that they just assume undergrads have no research experience and I'm guessing it isn't as big a factor as it might be with grad students/postdocs. I've also been told enthusiasm is a big factor, though I'm not sure how I'd show them my enthusiasm/passion over text (since I'd have to email them before meeting with them, assuming I met with them at all).

Is there anything else they look for?

[Assistant] You have to show genuine interest in their work. Don't send out the generic "I want research experience, are you looking for people?". Say you looked at their work and find X particularly interesting. Say you had some questions about Y paper or research. Ask if you can meet with them to discuss more. Then at that meeting, after you've talked for a bit, say it's really interesting and you'd love to do that type of work. Do they have any openings?


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

[User] [Lord of the Rings] How would the Fellowship's journey change if Gandalf the Grey survived Moria?

[Assistant]
Odds are high that Gandalf wouldn't have the power to remove Saruman's control over Thoden.  That would mean that Rohan would be completely removed from the equation and most likely destroyed by Saruman's Army.  Without Rohan's assistance at the Battle of Pellenor Fields and the addition of Saruman's Army, Gondor would most likely have fallen to Sauron's Armies as well.  Even if Gandalf got the Fellowship into Mordor and destroyed the Ring, the devastation wrought by Saruman and Sauron's Armies would have brought an end to the Kingdoms of Man.

Also it would be unlikely that Merry and Pippen would wind up in the company of the Ents.  If they aren't in a position to convince the Ents to march on Isengard, then Saruman's power base remains intact and his army able to be reinforced.


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

[User]
ELI5: Why does looking at a bright light leave image impressions for long periods?

When you look at something really bright ( a bare light bulb for example), why do we see that object when we close our eyes for several minutes? What happens to make this occur?

[Assistant] Very basically, the intense light "burns" an image into your retina. It takes time for it to normalize. What's going on is more about light and chemistry, but it's very simple to say that the light just "burns" an image in your eye and it takes a minute for your eye to recover and see clearly.


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

[User]
[Star Wars] If Palpatine was killed prior to the events of the movies, would Anakin still have fallen to the Dark Side?

Sidious was a major contributing factor to Anakin's fall, however he just helped him down a path that was already revealing itself to him.

Would Anakin eventually have fallen had Palpatine not intervened?

[Assistant] Well without Palpatine Naboo probably wouldn't have been blockaded so Qui Gon and Obi Wan may have never found Anakin and he may have just lived out his life on Tatoine becoming a successful Pod Racer.


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

[User]
ELI5: Why is FM radio on only odd frequencies and only frequencies between about 90 to 110?

Why can't there be a station on something like 95.4 or 56.1? Are these limitations of FM radio or are those frequencies just not allowed for public use?

[Assistant]
Only odd frequencies are used to prevent interference.

If you had two stations on 95.1 and 95.2, you wouldn't get a very clear signal out of either station. 95,1 and 95.3 are far enough apart that you can tune into either one clearly.

And the frequencies are between 88 and 108 MHz because the other frequencies are used for other things.  76.0-88.0 are reserved for over the air TV broadcasting.  108.0-118.0 are reserved for aeronautical navigation.


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

[User]
ELI5 How a casino knows that you're counting cards in your head?

So Ben Affleck has admitted to counting cards and was told not to play Blackjack at certain casinos. How does a casino know that he's counting cards if all the math is done in his head and they can't really prove it.

Thanks for the explanation and tips. Much appreciated.

[Assistant] They don't have to prove it. They watch your play style and if you are playing very well for a long time and appear to be matching the results of a card counter, then buh bye. It's not a right to be in a casino.


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

[User] ELI5:If 80% of taste comes from your olfactory receptors in your nose, why do some foods smell awful yet taste great?

[Assistant] It's more accurate to say *80% of tastes* than *80% of taste*. The flavors perceived by the tongue are by far the most important, though there are only five. Something that doesn't taste sweet, salty, savory, or sour isn't going to taste very good, even with a great aromatic profile. However, something with a bad aromatic profile can taste great if it's extremely savory, salty, and well-textured... take cheese for example.


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

[User] Is there any Mathematical reason that (-0.5)!^2 = Pi, or is it just a coincidence?

[Assistant]
It's not a coincidence. To extend the factorial function to non-natural numbers, you replace it with an integral. The factorial of x is then the integral of t^x e^-t dt from 0 to infinity, where t is a dummy variable.

For x=-1/2, this integral works out to the square root of pi. It is a similar integration to the Gaussian curve, which bounds an area of root-pi as well.


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

[User]
Does Jordan Peterson ever outline specific criticisms of specific radical theorists (Foucault, Adorno, Derrida etc.)?

Every time I heard him criticize critical theory (what he strangely calls "postmodern neo-Marxism"), it's something vague about "relativism," "destroying the foundations of the West," or "denying biological realities," etc.  Does he ever address Foucault's views on power-knowledge, Adorno and Horkheimer's Dialectic of Enlightenment, Derrida's ideas on differance, etc.?  Whenever I hear him speak on the subject it seems like he has a very superficial or flawed understanding.  I was curious if he ever deals with specific theories or ideas.

[Assistant]
From what I've seen, no. He doesn't know what he's talking about. That said, life's too short to spend it sifting through Peterson's massive online oeuvre.

He *does* talk about Heidegger a bit, but he makes a hash of it (such as getting hung up on the capital "B" in Heidegger's "Being," as though he has no understanding that alll nouns are capitalized in German.)

But who knows, maybe a Peterson sub could point you to specific discussions.


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

[User]
CMV: Teaching your kids to believe in Santa is stupid.

Note: this goes for other made up characters like the Easter Bunny or the Tooth Fairy.

As a kid, I never understood peoples obsession with Santa. Christmas is to celebrate the birth of Christ and sure its now evolved to include some gift-giving and a big celebration too Ive known that since age 3. But I never understood why other kids in my class would insist that Santa is real or why their parents would happily go along with it instead of just communicating the real meaning behind Christmas (Im not even Christian, so thankfully my parents never tried to push this nonsense on me). So heres why I think teaching your kids to believe in Santa is dumb.

1. It literally adds nothing to their life. Santa is nothing more than commercialized balderdash by corporations taking advantage of childrens navet. He isnt a God to pray to or instill moral values in the kid (other than be good, which is kind of meaningless). He isnt some celebrity or amazing selfless person to look up to and idolize. He isnt even real! Why feed your kid a load of commercialized bullshit, when instead you can be teaching them about the real world? You can teach them about why certain families can afford certain gifts and others cant, why certain kids in their class dont get gifts not because theyre bad but because they arent even Christian and dont celebrate Christmas, where these gifts come from and maybe the economics behind creating and selling these items during a holiday season, etc. Literally all of that is more valuable than peddling bullshit to your kids.

2. It probably teaches kids to not think critically about the world. First of all, kids shouldnt just be blindly believing what their parents tell them. They should be led to ask themselves whether its even possible for Santa to exist: How does his sleigh fly? How does he reach all 8 billion people in one night? How are his elves somehow able to create the brand new iPhone and package it in the exact Apple box it comes in? Furthermore, how is it possible for people to have explored the North Pole and yet never seen a trace of Santa? (I dont even know how kids themselves dont ask these questions on their own, because I did, but I have to imagine its in part due to a lack of emphasis on critical thinking in our education systems and the parents continuing to sell a crock of shit).

3. This just delays the inevitable truth from coming out. Your kid is going to find out that Santa doesnt exist if they dont come to that conclusion by considering his impossibility, theyre going to realize it because their parents are definitely buying the gifts. Why delay the inevitable? What does that even do to benefit the kid?

4. It teaches kids the opposite of learning good behavior for its own sake. Kids shouldnt be learning to be good because theyll get a present at the end of the year. They should be kind and respectful because its just basic human decency 101. So youre basically ruining their own development by linking good acts to rewards.

Anyway, open to changing my opinion but this is it.

[Assistant]
Id argue in question 2 that part of the point is to teach kids to think critically. Kids largely figure out for themselves on that the balance of evidence Santa doesnt make realistic sense by age ten or so. Its one of the first times kids can find out that they can come to a different conclusion than what the authorities in their lives are telling them and be right and encouraged in doing that.

It also teaches kids, once they inevitably do find out, that there parents have been giving them gifts for years with no intent on taking credit for it, which implies gift giving is an exercise in making the recipient, rather than the giver, happy.


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

[User]
ELI5: What exactly went wrong on Apollo 13 and how was so many things missed?

I just watched the Ron Howard film, and I have to say it was one of the best films Ive ever watched. But it left some unanswered questions in my mind, like how did this miss all those errors? As well, if they used the same rocket as the successful Apollo 11 and 12, what was the difference with 13? How was everything missed?

[Assistant]
Basically it was a design flaw, an assembly error, and a testing error: a chain of events that led to near disaster. Each thing on it's own wasn't enough to cause the explosion, but the unlikely chain of all 3. The genesis of it started in 1965, before the first Apollo spacecraft was even built. The spacecraft was originally designed with a power system to operate on 28 volts, but during the design process, this was raised to 65 volts to match the power supply of the launch tower. One of the subcontractors who built the oxygen tanks didn't change this, and continued to manufacture oxygen tanks meant to operate on 28 volts.

A few years later, in 1968, the spacecraft that was to be Apollo 13 was being assembled, and the oxygen tank was dropped, bending the vent pipe. It was determines the tank was still ok to use because there was no visible damage, so it was installed anyway. Later, during a test, the tank was filled with liquid oxygen as usual, but when it came time to empty it, it wouldn't drain, because unbeknownst to anyone, that pipe was bent. Instead, they decided to simply turn on the heater (the heater was used to turn the liquid oxygen in the tank to gaseous oxygen for use as needed) to let the oxygen vent off as gas overnight. Now here's where the wrong voltage comes into play. The thermostat attached to the heater inside the tank was supposed to cycle the heater on and off so it didn't get too hot, but the 65 volt power supply was too high for 28 volt circuitry in the tank and it blew out the thermostat. This meant the heater stayed on all night instead of cycling on and off, and as a result, it got so hot inside the tank that it burned off the teflon insulation on the wires. The next day when everyone came in, all they saw was that the tank was empty as expected.

Now it's April 13th, 1970. The spacecraft is 2 days into it's 3 day journey to the moon, and everything is going as planned. Mission control asks command module pilot Jack Swigert to stir the tanks. There's a fan inside the tanks that stirs the liquid oxygen to get more accurate quantity readings. So Swigert, flips the switch to stir the tanks. The electricity flows through the exposed wires inside a tank filled with oxygen and arcs, igniting some of the charred remains of the teflon insulation (fire + concentrated oxygen = bad).  This caused the tank to explode. The explosion slammed close the valves feeding the fuel cells (the fuel cells generated power), tore holes in the other oxygen tank, and blew off one entire side of the service module, also damaging their main antenna and the main engine.

Sorry for the long answer. The only difference on 13 was the dropped tank. That triggers the chain of events that leads to the explosion, It could have happened on any. previous flight, but it didn't.