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Say I was to have a star, with a mass of around 500 or so of our sun's mass. When it dies, and it will, how large would the supernova be? Would it even have one, or would the mass of it all skip the outward explosion stage and become a black hole directly?
How would one figure this shit out anyways? Could one figure out the size of the stellar boom for n masses of sun?
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>>10974074
It's not just the amount of mass. Two stars made of different material will react differently when/IF they nova.
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>>10974074
The upper limit to a star's mass is about 100 solar, since any higher than that, fusion goes so fast, and the temperature gets so high, that radiation pressure prevents further accretion. All stars near that upper limit form black holes at their cores when they die in hypernova explosions.

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Why?
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>>10974790
why not retard
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>>10974790
empty set is unstable
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>>10974790
This thread made me cry I laughed so hard. This is the lowest effort thread yet. Really, a marvel in its field. I think I'm taking crazy pills

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What IQ do you need to do math? Is Terence Tao's statement that you don't have to be a genius a massive cope?
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>>10974693
Based
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>>10974665
I tested my IQ once and it was around 120. I don't care, I can learn it, others can too if they really want to.
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>>10974693
Quite the opposite, geniuses use denial of IQ as an excuse to inflate their own efforts and hard work, whereas in reality a lot of it is just due to natural talent and luck.
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>>10974747
I think that is an insult to geniuses. Geniuses work even harder than anyone because they are usually pressured by a sense of duty to use their exceptional intelligence to the best of their ability. Imagine racking your brain for years desperately trying to prove a conjecture, knowing you will probably fail and die in obscurity. Puts the ol 9-5 to shame.
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>>10974361
After seeing that pic I wanted to know how much I understand pytaghore theorem by proving it and I had more trouble than I thought (used four rectangles).

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how many years does earth have left?
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>>10968462
Can't we just send a Unobtanium train into the core and kickstart some regenerative process by dumping a few nukes?
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>>10968462
it depends what Al gore, UN and that 16 year old girl says, if these people say that next week is going to end, will end.
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>>10968462
4 billion or so.
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>>10974750
Actually less than 1 billion years for complex life even assuming no climate change from CO2, because Sun is getting significantly brighter as it ages.

Your daily reminder than our biosphere is already the planetary equivalent of an old person.
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>>10974764
In that case the earth better hope that humanity survives, because by then we'd surely be able to move the planet to safety. Or simply add fuel to our star to keep it burning for longer.

Why doesn't /sci/ talk about Archaeology much? I thought this was a REAL science board.
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>>10972738
The gap between this Neanderthal's upper lip and his nose is huge. Are there any normal humans with it?
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>>10973785
What are you talking about?

>>10973827
This is apparently a picture of Homo Heidelbergensis.
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>>10973785
It's pretty fucking proven
>>>/christ/
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>>10973827
Does this count as normal?
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>>10974158
>This shirt.
...I-it is in Portuguese
Probably about a Festa Junina.
Oh fuck, Brazil do suck.

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>particles exist in a probabilistic superposition
>the probability field of any particle extends across the entire universe
>in an infinite universe, the probability of a particle being very very far away from the center of the field inevitably adds up to 100% (or 99.99999...)
>all matter would instantly disintegrate across the cosmos in the universe was infinite
How is this even a debate in physics?
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>>10974680
The universe has only a set amount of energy.
It can only expand into itself so much, even assuming the heat death scenario which makes no sense because gravity doesn't take vacations.
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>>10974680
does space have birds
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>>10974733
Conservation of energy does not globally hold in general relativity, and doubly so in the presence of Inflation. Also, total energy of the universe may be zero.

That said, I dont think it is infinite.
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>>10974733
>It can only expand into itself so much

This is contradicted by the observation that expansion is noticeably speeding up.
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>>10974733
>The universe has only a set amount of energy.
Wrong. Expanding space has a constant energy density.

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Many years ago, for the briefest of moments, /sci/ used math captchas, and the board was better for it. Why not bring those back? I don't mean simple math either.
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>>10973697
Considering there's no "x" to solve, I think you are on to something.
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>>10972070
>3 and 4 ambiguously worded.
>"If you bought your parents to separate gifts..."
Yeah, that will weed out the brainlets.
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>>10973187
>I posted 7 of those
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>>10972055
Hand written math expressions? We would maybe finally get usable photo to math for "higher" math (I'm undergrad so I know shit about higher math but you know what I mean). It would be so nice if I could just take a photo of my notes and export them into latex.
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>>10974198
>It would be so nice if I could just take a photo of my notes and export them into latex.
I thought that could happen now.

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Im not a mathematician or a logician, but i do keep hearing a lot on how Gödel's theorem placed a blade of Damocles above mathematics, but im not sure how his theorem could have such a destructive impact on math. Could anyone elaborate?
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>>10973896
>Let's now assume that RH is undecidable
if RH is undecidable, then in particular we can't disprove it. which means it is impossible to find nontrivial zeros outside the critical line. but if there were nontrivial zeros outside the critical line, we would eventually find them.
therefore there aren't nontrivial zeros outside the critical line and RH is true
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>>10973896
>but doesn't mean it is a god or godlike
I don't quite know what godlike means desu.

>and it was pretty clumsy of you to misunderstand my intentions with it too.
I wouldn't call it clumsy, as after thoughtful consideration I still don't get it. So maybe I'm more than clumsy.

>Let's also assume that RH is true. I.e. that there are no nontrivial zeros outside the critical line. Hence, no matter complex number we pick inside the critical strip outside the critical line, it will never be zero. Let's now assume that RH is undecidable. This means there exists no formal proof for this fact. It is still a fact. We just don't know it.
I think there's a notion in which, when it's undecidable, it makes no sense to say that either is true. It's not clear to me that "Let's say 'in reality there is no complex number such that the zeta function is zero on the strip" is a sensible notion if it's undecidable.
I think this is at the crux of the matter here. It's also part of the Platonical stance to think of mathematical inquiries having truth values despite no conscious being nor formal system being able to relate to it.
I know this a kind of formalist view, but we don't have to agree.
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>>10969220
Saying the incompleteness theorems have disastrous consequences for mathematics as a whole is like saying the disagreement and various paradoxes apparent in the realm of Quantum physics means force x mass doesn't equal acceleration.
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>>10970700
>Russel's Paradox
Russel's paradox is fucking retarded.

>Let us write 2 + 2 = 5
>but 2 + 2 is equal to 4, not 5
>how ever could we resolve this utter paradox????????
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>>10974731
Based retard (I actually mean it this time)

People are always whining about photovoltaic cells requiring rare minerals that are environmentally unfriendly to mine and whatever so why aren't we just doing solar energy through the mirror method?
is photovoltaic really more efficient than just heating up some water with the suns heat and running that shit through a turbine, this method just requires some good ol' fucking steel and idk what else
like yeah sure this method isn't usable for smaller applications but it is very much usable for big power plants which ought to make up the majority of solar power production anyhow
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>>10973140
it's not, the US is huge, you can build much more
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>>10969385
hydropower with significant reservoirs of water tend to release methane to some degree
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>>10962741
extinct humans don't care what turbines look like, just like no one cares what a power grid or an oil rig looks like.
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>>10973208
On Google Maps it seems quite a lot of the mirrors are missing or pointing in odd directions.
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>>10974390
your ass is releasing methane to some degree

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His major? Chemical engineering (drops out 3rd semester due to being unable to keep up with the coursework)
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>>10974315
>>10974310
Average (mean) Engineering starting salaries:
Bachelors: 69k
Masters: 82k
Doctorate: 102k

If you figure 20k a year for post-bachelors schooling and 4% average pay increases, then it takes about 25 years to break even. Hopefully it's a career you enjoy.
>>
>>10974335
I tried doing this algebraically and maybe it's because its 6am and I never went to bed or I'm just a brainlet, but this is as far as I got:

69000(x) = 102000(x-4) - 80000

x = 14.8, which is the number of years worked with a bachelors. How would I get it to the 18 which matches the data?
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>>10974681
other than just adding 4 at the end obv
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>>10974295
>Watches anime but relates to the villain
>99% of all anime villains are just "heh, I'll wipe out ur whole village because I feel like it".
>Becomes an ascended God for no reason
>0(zero) character depth or development
WeW
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>>10974295
Is it because he wants to make bombs?

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How quickly could you send stuff between Earth and Mars if you built a giant railgun in Earth's orbit?
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There's clearly very little understanding of orbital mechanics and too much political whining in this thread.
Why don't you guys go ask your parents if they'll let you buy Kerbal Space Program and then come back?
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>>10974641
Here we have the classic example of a jackass.
A jackass has no information to offer, only insults.
A jackass knows nothing but pretends he does.
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>>10974656
If this thread is really full of experts then why does it take 25 posts before OP gets the very basic answer to his simple question: it takes as much time as any conventional technique ~7 months
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>>10972274
Depends on how big the rail gun is. The problem is getting the payload into space. The advantage is that you would only need propellant to get to LEO and rendezvous with the gun. The gun provides the delta v to intercept Mars, the remaining propellant inserts it into orbit. Probably not much faster but maybe more efficient.
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>>10973958
I really want this not to be true but I know it is. And yet I keep dreaming of space exploration. Why does it have such a pull?

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>>10973905
It becomes more buoyant so it weighs less when weighed in air.
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>>10973270
>>10973278
same
>>10973275
>>10973282
no

Anyone saying otherwise is either pedantic or retard.
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>>10973905
We're already aware you don't know shit about physics, no need to post cringe wojaks.
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>>10973912
>HDD
>etching
Is it summer already? HDDs work by magnetization you turd. You're thinking about CDs.
>>
The one turned on will be lighter. duh!!!

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Does this thing actually have an answer or is it a big troll?
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>>10973259
3 within sequence always contains something that is in the 2nd sequence, so i would like to say #2, but the tertiary options are fairly imperfect in consideration.
t. iq of 87 and shitfaced
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>>10974477
>He thinks his IQ is 87 because an elitist Mensa test to rout out geniuses for their stuffy organization told him so
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>>10974494
Cope harder
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>>10973259
I'd say 1 simply because there are always broken mathematical symbols on each line.
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>>10974567
I got 131 and 133 on the WISC and iqtest.dk. respectively. I'll take those numbers over "le epic sekrit society" test any day of the week

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Will the gene pool be inhabited by less and less ugly genes in the future?
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>Having this much of an inferiority complex for white girls

Pathetic

Literally IMAGINE not being white lmao
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>>10974538
Imagine being part of a race close to extinction.
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>108 replies of 4chan incels arguing about beauty like teenage girls on the fucking science board
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>>10973296
Letting it rot is how they got stuck with endless population growth, did you even do GCSE geography?
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>>10969407
> be a dirt sucking delivery man
> deliver to the home of a wealthy family
> woman comes to the door dressed like a thot but lacking any physical traits that push her above a 5
> see this post a few days later implying the genetic superiority of aristocrats by claiming that common folk are inferior

This stinks of 16th century absolutist bullshit.

Formerly >>10913113

Try and keep the stupidity to a minimum.
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I'm not sure of the progress on growing animals/people in vats (there was that calf grown or partially grown in a bag that people were posting here several months ago) but I was wondering whether when that technology becomes viable, if it's before 3d printing organs is viable, whether we would grow humans in vats that were altered to be braindead to be harvested to organs.

Also why don't we do that now, or at least study and research it? The only ethical concerns would be to the mother who would be needed for the first 9 months.
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>>10974296
Pretty sure ethics and support are the main reason, but realistically and scientifically flawed. You could grow a human, but humans are vastly complex. Even between two humans, transplanting organs requires very specific properties or else the transplanted organ will just get deleted and kill the patient. Unless you could somehow alter clone humans to perfect match the necessary terms for a transplant then it wouldn't work. It basically comes down to being a lot of work before it's even feasible and no one will want to spend the time on that even if it does potentially have a lot value in the end.
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>>10946298
ok I got a real stupid one.

tl;dr I want to take someone's last name and use the letters to form a compound. Doesn't NEED to be in order because of....

I want to take said plausible compound and make one of the 2d models of the compound so I can 3D print it, and then cast it as a wall hanger.

With knowing only a passing amount (the required in uni for mech eng degree) about molecular chemistry, is there a resource or "calculator" I can use to generate a 2d model of a compound after balancing it?

It's very important that the end result be plausible as a compound, not common, not anything, just correct. It's a gift for someone in the chemical field.

thank you for any advice.
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>>10974302
so organ transplant is way more specific than just blood type or something. Is there anything you can select for at the embryo / sperm level to hit specific groups of potential recipients? Barring that, aren't doner lists usually in the thousands or more anyways? Why not just make a braindead human and then find a match for them on the list because surely someone will come close and at the very least that shrinks the list. As for the feasibility, I can't find any sort of experiments done or research into the idea, can it really be said to be too difficult if no one has seriously tried?
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>>10972894
do exercises


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