/sci/ - Science & Math

[Black holes are just dense obj(...) No.9344317]

>Watch any pop sci doco about astronomy
>They get to black holes
>The narrator stars to spew a bunch of mumbojumbo about how "physics breaks down" inside black holes
>Says bullshit like there could be miniature universes inside black holes, or wormholes to other dimensions

Where did this crap come from? A black hole is very obviously just a lot of matter that has collapsed on itself. The inside of a black hole is just some really warped space and a singularity. There's very likely to be no leprechauns in them. Just compressed space

[Anonymous No.9344319]

You can say anything you want about something mysterious and get a shitload of views.

[Anonymous No.9344321]

>>9344317
People love magic, people really love it when they can 'explain' their magic and make themselves seem 'intelligent'.

[Anonymous No.9344325]

>>9344317
Popper. Anything that could be proven wrong is now science until proven wrong.

[Anonymous No.9344328]

>>9344317
An ER bridge is a wormhole made by gluing two black holes together.

[Anonymous No.9344330]

>>9344317
>a lot of matter

[Anonymous No.9344331]

>>9344328
>FTL travel

[Anonymous No.9344335]

>>9344331
You can't exit an ER bridge.

[Anonymous No.9344337]

>>9344335
You can if you're a Hawking radiation. :^)

[Anonymous No.9344338]

>>9344317
>The narrator stars to spew a bunch of mumbojumbo about how "physics breaks down"
Except that's the case, brainlet. How the fuck do you even begin to account for infinite density and gravity, let alone how/when we go from TR to QM?

[Anonymous No.9344344]

I believe at least some of it comes from Penrose Diagrams that feature event horizons. People often extend them to claim that a black hole becomes a bridge to a "parallel universe" at the moment of it's creation. It's just a quirk of mathmetics, though. The same diagrams claim that white holes exist. If white holes existed, they would be very easy to spot. The fact that we've found black holes - which are proverbival needles in haystacks - yet not white holes - which would be brighter than anything- is fairly damming proof that it's all just imaginary.

[Anonymous No.9344363]

>>9344338
Our guy Eisenstein got it right several decades ago.This is all a black hole is, spatially speaking. It's just a very dense object that gives space time a hard pinch. There's nothing magical about it. Inside one, there's likely just of curved space and a singularity.

[Anonymous No.9344364]

>>9344344
white holes must exist, the light just doesn't reach us

[Anonymous No.9344373]

>>9344317
They over-dramatize it.
What they _mean_ is that the equations of General Relativity break down. You get singularities. I am using that word in the sense that mathematicians do; regions where no values can be computed and no predictions can be made. It's like asking about a line tangent to the corner of a rectangle. The slope is discontinuous there.

There are (very likely) no leprechauns in there, nor a gateway to Hell (as a particularly bad movie posited.)

Incidentally, "compressed space" may not be a good way of putting it. Black holes are always described (rigorously) by their circumferences, never their radii. The radius might be infinite. Think of those rubber sheet diagrams where a point is pressed down to form a funnel. The rubber is stretched indefinitely "out of the plane" and radial lines drawn on the surface get longer and longer and longer.


>>9344328
Not two black holes. By definition, event horizons are one-way. A tunnel you can enter but never leave (save possibly as thermalized hawking radiation) does not strike me as an efficient way to get from "here" to "there".
Wormholes _are_ valid solutions to Einstein's equations, but the ends aren't black holes. That's another pop-sci simplification.

[Anonymous No.9344378]

>>9344363
>>9344317
>just a large pinch lmao
>black holes are so simple dude
guys please, we have very little understanding of black hole physics yet
like this problem:
https://en.wikipedia.org/wiki/Firewall_(physics)
or what happens to the stuff in the black hole accretion disk when it evaporates

I suggest watching a Susskind talk about those issues:
https://www.youtube.com/watch?v=B2ksDczJOAs

[Anonymous No.9344388]

>>9344363
That is, unless pic related is true. Although I'd imagine that if black holes could funnel matter somewhere else like this suggests, then the black hole would loss mass nearly infinitely fast and dissolve as quickly as it formed. Since black holes stick around, and grow, it's safe to say that any matter that enters them isn't going anywhere.

[Anonymous No.9344415]

Won't time dilation make it impossible for the matter to actually reach black hole in finite time?

[Anonymous No.9344428]

>>9344317
>Where did this crap come from?
A lot of physics equations take density into account. Try calculating density when volume=0.

[Anonymous No.9344436]

>>9344428
Something humans are good at is understanding things non mathematically. For instance, a rock. You can pick up a rock, and you will know that it's a rock. You don't need equations for this. Your brain is able to understand what is in your hand without any maths involved at all.

A black hole is just like that rock. We know what it is, even if physics does not. Density equals infinity when volume is zero, by the way.

[Anonymous No.9344450]

>>9344317
>physics breaks down
its actually accurate , the physics (by which i mean the theories of physics) have never been tested in the vicinity of black holes in any way.

what i think is going to happen is we'll figure out a way to make artificial ones at some point and do experiments with them.

[Anonymous No.9344462]

>>9344337
No, you can't. The bit that exited was on the outside, it's partner wasn't.

[Anonymous No.9344466]

>>9344462
How do you know? Are you observing it? :^)

[Anonymous No.9344469]

>>9344317
What video did you watch? Cuz... Your after greentext summary is basically what most of them say. I've yet to see the one that mentions leprechauns.

Physics still work, just not as we know them, the discipline we've invented called physics breaks down - but the universe keeps right on going as usual - just, more strangely than usual from our perspective, with time and space flipping on their heads in shit. This breaks our tiny little minds - but the universe doesn't care about how we think physics are supposed to work.

And it's our physics that predict the possibility of wormholes, but, so far as we can tell, the universe has yet to display giving a shit. Then again, we had initially assumed black holes were a side effect of the math, figuring something most prevent such unthinkable things where all our work would mean nothing, until we started spotting all these super massive event horizons that nothing else could explain, and eventually realized they are a good portion of make galaxies work.

[Anonymous No.9344472]

>>9344466
I don't have to observe it to know how the theory is supposed to work - if it's escaping the event horizon, it ain't Hawking Radiation, but some other crazy shit we've not yet come up with.

[Anonymous No.9344474]

>>9344472
Well, it's in superposition, so if you observe it, I cannot pass through the event horizon, but if you don't, I do.

[Anonymous No.9344477]

>>9344317
Dude haven't you seen interstellar lmao

[Anonymous No.9344501]

>>9344474
That's not what "observe" means in that context - it means to interact, not "see". From my perspective, you never enter the event horizon, and just slowly red-shift into invisibility, but from your perspective, you go in just fine, whether I'm looking or not.

Then, if you're looking back at me, and don't blink, you get to watch the entire universe die of heat death, as time and space swap places and now the singularity is no longer a location, but a time in your distant future that you will never reach, while anything closer to the event horizon than you is effectively in your past, and, should you have something to allow you to move, depending on which way you go, light from the past or future may come to you, creating the seeming effect that you can move through time, while this act accelerates you towards your final future, where you'll be reduced to a series of particles in a line, each moving away from the other at faster than the speed of light as space moves faster and faster towards the singularity that is always ahead of it, until each of your particles is effectively in their own observable universe. ...Though you were probably ripped to shreds before you got anywhere near the horizon, reduced to particle spaghetti before you went in, and less than that, if cosmic censorship is true.

So you can see why sometimes folks wax a little poetic about these things.

[Anonymous No.9344525]

>>9344501
Whoa, what a way to go.

[Anonymous No.9344576]

>>9344436
>Something humans are good at is understanding things non mathematically. For instance, a rock. You can pick up a rock, and you will know that it's a rock. You don't need equations for this. Your brain is able to understand what is in your hand without any maths involved at all.
>A black hole is just like that rock.
What the fuck are you talking about? We have no concept of black holes outside of physics. There is nothing you have interacted or ever will interact with that shares any property in common with a black hole.

[Anonymous No.9344648]

>>9344415
Yes. Viewed from "flat space" objects take infinite time to reach the event horizon.
A "white hole" would just be a time-reversed black hole. So it would take infinite time for anything to emerge from the hole -- or for the hole itself to pop into being.
That's why hardly any physicists believe they can actually exist. Read Kip Thorne's book on why "Interstellar" is BS. (He was technical advisor on the film and told Nolan so, but was ignored.)

[Anonymous No.9344737]

>>9344576
>There is nothing you have interacted or ever will interact with that shares any property in common with a black hole.
You are just begging for a "your mom" joke, aren't you?

[Anonymous No.9344746]

>>9344317
Wow check that webm! Real actual footage of a black hole they captured when they went flying into space with a film crew!

You can tell it's real because l@@k at the gravitational lensing!

[Anonymous No.9344759]

>>9344746
Think it's Space Engine - which is actually a really nifty program.

You do realize that %99.999 of every astronomical "photo" you see is an artist's rendition? Fuzzy blips, radio telescope data, spectrocity charts, and gravimetric ligo charts don't look very interesting.

[Anonymous No.9344765]

>>9344317
>>Watch any pop sci doco
Why?

Popular science is intended to make you believe that you understand a thing which actually you don't understand, and to gratify what I believe to be one of the lowest desires of modern people, namely the superficial curiosity about the latest discoveries of science.

[Anonymous No.9344770]

>>9344317
>compressed space
space is not a thing... it's where things are. Space is nothing, and "nothing" can't be compressed or anything like that

[Anonymous No.9344779]

>>9344759
Think Event Horizons due to attempt to give us a good image of Sagittarius A's event horizon via VLBI, which should look like, something.

[Anonymous No.9344781]

>>9344770
Wow, are you ever going to have your mind broken when you realize how your cell phone's map function works.

[Anonymous No.9344786]

>>9344781
Pls elaborate.

[Anonymous No.9344792]

>>9344786
Not him, but GPS works, because we do relativity calculations between the network of satellites and ground stations to compensate for the time dilation that occurs from their relative speed distance and being in less curved space, higher in the gravity well. Otherwise, by the end of the week, your smartphone would think you were on the other end of the nation. It uses the same general relativity formula that initially predicted black holes, and has to be accurate, in this case, to sixteen digits.

http://www.astronomy.ohio-state.edu/~pogge/Ast162/Unit5/gps.html

[Anonymous No.9344801]

>>9344792
Now tell him about vacuum energy and how space isn't actually nothing.

[Anonymous No.9344802]

>>9344801
Giving him the relativity mindfuck and the quantum mind fuck, both in the same day, maybe a bit much... Although I suppose black holes do involve both mind fucks.

[Anonymous No.9344815]

>>9344792
Wow that's by far the most practical application of relativity I've heard.

[Anonymous No.9344823]

>>9344378
>black holes are so simple dude
Classical black holes are very simple mah dude. In any GR course it's the first solution of the EFE you will study.

[Anonymous No.9344826]

>>9344815
Comes up more often than you'd think - basically whenever there's two atomic clocks timing fractions of a picosecond shit more than a few miles apart, or even at different altitudes, and of course, anytime we communicate with anything outside the atmosphere in a fashion that needs to be even marginally well timed.

I'm just glad the universe is uniform enough to allow the formulas to work so smoothly. Given how wonky it gets at quantum levels, it's kind of amazing how much simpler things get the further you go out... Well, until you go too far out. Not that the Earth's gravity is perfectly uniform, but it's close enough (and even in those rare instances where it isn't, well, that's why we made gravity maps like pic related).

[Anonymous No.9344835]

>>9344436
This has to take the prize for the most retarded unscientific comment ever written on this website, fuuuuck me.

[Anonymous No.9344858]

>>9344823
why don't you listen to the talk instead of thinking your freshman course told you everything you'll ever know about physics

[Anonymous No.9344884]

>>9344317
>complains about people spouting bullshit
>starts to spout bullshit himself
Black holes don't exist.

[Anonymous No.9344906]

>>9344792
The map is not the territory, retard. The fact that you can model some phenomenon a certain way doesn't necessarily imply a one-to-one correspondence between what goes on in your model and what goes on in reality.

[Anonymous No.9345042]

>>9344501
One of the better explanations in this thread

[Anonymous No.9345045]

>>9344317
>A black hole is very obviously just a lot of matter that has collapsed on itself.
define "collapsed"

[Anonymous No.9345055]

>>9344436
I can see what you're getting at, but this intuition comes from thousands of years of looking at rocks. Humans haven't been observing black holes for long enough to have any sort of intuition about them, and are also unable to compare them very well to much of what we see.

[Anonymous No.9345395]

>>9345042
No, he's wrong about never reaching the singularity. You'd reach that very quickly. The black hole's ability to stretch space does not outmatch how fast you you fall into it through that space. The stretching and the gravity act as a double conveyor belt that gets you to the singularity in real time, real fast.

[Anonymous No.9345401]

>>9344317
It's because of the Schwarzchild radius, our observable universe is contained inside it's own observable schwirzchild radius. I still think there is some bullshit in it.

[Anonymous No.9345415]

>>9344648
Wrong. Viewed from flat space, we can't see something cross the event horizon because its light gets redshifted into infinity as it crosses it. When the object is almost frozen, we do have all the confirmation we need that the object has passed the event horizon. There's no need to bring time dilation into it. For the object's sake, it notices nothing. Time dilation is never felt by the object experiencing it. It would merge with the singularity in real time, from it's perspective.

[Anonymous No.9345421]

>>9345401
Btw, the density of a black hole can be really low after all, the definition of a black it's an object which scape velocity is equal or bigger than the speed of light. The Swarchild radius analize this kinda shit.

[Anonymous No.9345432]

>>9344388
This is just one of the solutions of Einstein's equations.

[Anonymous No.9345435]

>>9344344
That's because black holes don't have event horizon.

[Anonymous No.9345442]

>>9345435
Oh yeah? Awesome, please show your proof of that. I'm absolutely dying to see it.

[Anonymous No.9345443]

>>9345435
>black holes don't have event horizon.
Lel

[Anonymous No.9345474]

>>9344466
We haven't observed hawking radiation, full stop. The way it is stated to work involves a black hole giving energy to a virtual particle pair that spawned just outside of the event horizon and was broken up by the gravity gradient. It doesn't work any other way. So either hawking radiation isn't real, in which case all matter stays in, or it is real, and the radiation a black hole emits is really just a particle it pulled out of nothing, as opposed to something from within itself.

[Anonymous No.9345475]

Any statement about black holes is vacuously true.

[Anonymous No.9345477]

>>9345395
No, he's right, you don't reach the singularity. It's collapsing eternally, and is stretching space along with it at faster than the speed of light (cuz while matter can't do that, space can). Nothing can ever catch up with it, as, from inside the event horizon, it is effectively infinitely far in the future.

[Anonymous No.9345496]

>>9345475
this

[Anonymous No.9345502]

>>9344906
>The map is not the territory, retard. The fact that you can model some phenomenon a certain way doesn't necessarily imply a one-to-one correspondence between what goes on in your model and what goes on in reality.
That's very true, but when the map says there's a mountain, and you see a mountain, you kinda assume it's a mountain. In this case, everyone thought the map was wrong, until we started seeing mountains, and that includes the guy who designed part of the map.

Unless, of course, you have some other explanation for what these supermassive objects, that don't shine, and are far smaller than that amount of mass has any right to be.

I mean, I might be up for alternative explanations that nix singularities. There are a few, they just have consequences that mesh with other well established observations, or aren't tied to anything testable. But the supermassive event horizons are plainly there. If they weren't, if it wasn't possible to pack so much matter in once space that it would create such an effect, then these galaxies wouldn't be here - or at least wouldn't take the relatively calm ordered orbits they do - and thus, neither would we.

[Anonymous No.9345509]

>>9345435
A naked singularity would be rather obvious - and probably actually more dangerous.

[Anonymous No.9345510]

>>9345474
It was fucking joke, notice the smiley.

[Anonymous No.9345513]

>>9345509
How would it be dangerous?

[Anonymous No.9345521]

>>9345510
I thought that just meant you were a kid or something.

[Anonymous No.9345523]

>>9345502
They're cold neutron stars.

[Anonymous No.9345527]

>>9345474
>We haven't observed hawking radiation, full stop.
Well, we wouldn't expect to see it from out in the universe, as black holes large enough to spot from this far away don't even emit enough of it to power an LED bulb. The bigger the hole, the less Hawking radiation.

The disturbing bit is that we didn't observe it in CERN either.

I say disturbing, cuz if they don't evaporate, we may be in trouble - though I suppose we get clues as to that for about a century. (Albeit, cosmic rays hitting the atmosphere would caused the problem ages ago, so we're probably good.)

[Anonymous No.9345542]

>>9345523
Those are larger with the same mass, have no mechanics to hold them together if they were any larger, and ARE THE BRIGHTEST STARS AROUND cuz the only thing keeping them from collapsing is neutron (and possibly quark) degeneracy pressure, being macro scale quantum objects. There's just no way for a neutron star to be dark or have that much mass at that size.

...and you certainly can't have a neutron star with a radius several hundred times the size of our solar system. Balls of neutronium can't be much larger, than our moon. Eventually the neutrons will be under so much pressure that they'll be so energetic as to start combining with oppositely charge neutrons, become bosons, and no longer have the Pauli Exclusion Principle to prevent them from occupying the same space.

[Anonymous No.9345551]

>>9345513
Cuz instead of having a hole in space that was tucked nicely inside an event horizon, you'd have a hole in space that was expanding into the universe.

There's theories that if black holes happen to ring together in the right order, they may temporary expose a naked singularity - it'd be gone before it was a real problem, but the brief moment it was exposed, it'd put out more gamma rays than your average quasar, frying anything in the galaxy it was in. We've yet to observe anything like that though, so we assume (or hope) it isn't actually possible.

Not that regular old quasars aren't bad enough.

[Anonymous No.9345557]

>>9345527
I think you're wrong about it not being observed. From wikipedia:

>Under experimentally achievable conditions for gravitational systems this effect is too small to be observed directly. However, in September 2010 an experimental set-up created a laboratory "white hole event horizon" that the experimenters claimed was shown to radiate an optical analog to Hawking radiation,[27] although its status as a genuine confirmation remains in doubt.[28] Some scientists predict that Hawking radiation could be studied by analogy using sonic black holes, in which sound perturbations are analogous to light in a gravitational black hole and the flow of an approximately perfect fluid is analogous to gravity.[29][30]

[Anonymous No.9345559]

>>9345542
Neutron stars can be black. Most, in fact, are. You're mistaking neutron stars for quasars.

[Anonymous No.9345561]

>>9345442
Similar to how nothing would reach event horizon due to time dilation, collapsing mass doesn't develop enough density in time to create event horizon, it slows down before that due to time dilation.

[Anonymous No.9345562]

>>9344317
What the fuck do expect? It's pop science. It's supposed to create interest in science and the natural world, maybe sow some seeds that one day grows into a tree. Did you expect the very latest theories on black holes described in the highest levels of physics and mathematics?

Hatred for pop sci on /sci/ is disgusting. It's perhaps one of the greatest tools to spread scientific information to the general public who would otherwise never, ever learn about it. But oooh nooo it's not university level maths boo fucking hoo.

[Anonymous No.9345565]

>>9345557
Eh, this sounds only a bit better than trying to demonstrate the patterns galaxies take by making whirlpools in water.

I'm not doubting it happens, much, but this doesn't sound like direct observation of the phenomenon. It is something CERN should have produced, but didn't - but CERN's been doing a lot of odd things that have been John Snow'ing us for awhile.

[Anonymous No.9345568]

>>9345551
I don't think that's right. A naked singularity is simply a black hole that spins so fast that the event horizon shrinks below the singularity doughnut. Such a thing is theoretically possible, but unstable, and would stabilize into a regular black hole in seconds. It would emit some light, but I think nothing threatening to all life in a galaxy. The supernova that created the black hole would probably emit more radiation.

[Anonymous No.9345571]

>>9345559
Bullshit. No dead star has cooled enough to stop emitting visible light yet.

[Anonymous No.9345576]

>>9345571
>No dead star has cooled enough to stop emitting visible light
Apart from all that have.

[Anonymous No.9345580]

>>9345576
No, literally none have. The universe is far too young for that to have happened yet, you lying fucker.

[Anonymous No.9345587]

>>9344765
> what I believe to be one of the lowest desires of modern people, namely the superficial curiosity about the latest discoveries of science.
Out of what twisted manifestation of your own insecurities does this make sense to you? You're actually demonizing curiosity? You see a lot of incredibly stupid shit on this site due to all the neonazis, but jesus, this one stands out.

[Anonymous No.9345589]

>>9345559
Quasars are large angry black holes with accretion discs in crack mode, often emanating more energy than the galaxy they are in (sometimes by a factor of billions), in jets often longer than most galaxies. If you treat them as single objects, they are the brightest *objects* in the universe.

Pulsars (maybe you're thinking), are neutron stars spinning off energy at ludicrous speeds, and the brightest *stars* known. They do not, however, hold even a candle to a fucking qusar. There's thousands of pulsars in our galaxy, and we're fine. One good quasar, even as far away as the Andromeda galaxy, would eventually be a threat to us - one in our own galaxy would put an end to all life in it in short order. The nearest quasar is in the center of Markarian 231, some 581 million light years away - so far that we couldn't even distinguish a pulsar in that same galaxy, even with Hubble.

There are no dark neutron stars. You can't make neutron degeneracy pressure to hold them up without emitting a whole lotta radiation.

[Anonymous No.9345592]

>>9345580
>muh big bang
The fuck outta here.

[Anonymous No.9345594]

>>9345589
>Quasars are large angry black holes with accretion discs in crack mode
No.

[Anonymous No.9345596]

>>9344317
Are you trying to tell me a big bang couldn't happen inside of a black hole?

[Anonymous No.9345597]

>>9345587
I was thinking what you thought at first, but then I considered that he may have just been saying that it's a desire that is small, instead of (morally) low. I decided not to say anything, because if the guy is too dumb to realise he is being incoherent, he is not worth talking to.

[Anonymous No.9345603]

>>9345576
>>9345571
Well, there are some brown dwarfs that are pretty dim.

I suppose the ones that exploded and became black holes have *technically* stopped emitting light. Stars big enough to do that don't live very long, so there's plenty of those.

Neutrons stars just plain old don't burn out though - they are the longest lived stars in the universe, and if anything kills them, it'll be collapse, which they are all on the verge of. Pulsars slow over time, and eventually become the harder to detect regular neutron stars, but pulsars have been detected more than 10 billion years old (and that one is still rotating once every 8 seconds). Near collisions should cause them to slow sooner, if they don't simply make them collapse.

But we've already seen for ourselves what happens when two neutron stars collide - as predicted, black hole.

[Anonymous No.9345605]

>>9345594
Stop shitposting. You're wrong, but you can't admit it because your reptilian brain is compelling you to be stubborn in the face of evidence that would make you look stupid in your social group if you accepted it. But anyone with a mammal brain can already see that you are being stupid.

[Anonymous No.9345607]

>>9345603
>Well, there are some brown dwarfs that are pretty dim.
Yes, but brown dwarfs are technically not stars. They never managed to start fusion. They are just very large, very warm, planets, that got the "at least you tried" prize. (Though they do last near forever.)

[Anonymous No.9345613]

>>9345603
A brown dwarf isn't a star. Neither is a black hole. No dead star that isn't a black hole is dim enough to form a black dwarf. There are only white dwarfs and neutron stars. Both are going to be emitting light for a long time yet.

[Anonymous No.9345615]

>>9345605
This sort of sci-fi bullshit should be banned from /sci/. There is no evidence that quasars are black holes with accretion disks. Now fuck off.

[Anonymous No.9345616]

>>9345615
Nothing else we have ever theorized about could contain the mass they do, in the space they do, and do what they do.

Flat earthers should be banned from /sci/.

[Anonymous No.9345617]

>>9345603
>we've already seen for ourselves what happens when two neutron stars collide - as predicted, black hole.
Rubbish.

[Anonymous No.9345619]

>>9345616
>Flat earthers should be banned from /sci/.
I agree. As should your kind. Take this phantasmagorical crap to >>>/lit/ or some shit.

[Anonymous No.9345621]

>>9345615
>>9345617
Stop shitposting.

[Anonymous No.9345623]

>>9345621
You first.

[Anonymous No.9345625]

>>9345617
Fuckers got a nobel prize for that observation... Where do you think the two neutron stars went?

[Anonymous No.9345629]

>>9345625
Nowhere.

[Anonymous No.9345633]

>>9345629
So black holes don't exist, but neutron stars can just vanish from the universe without making one... Okay then.

[Anonymous No.9345637]

>>9345633
They didn't vanish dumb-ass. They exploded. The neutrons dispersed in interstellar space.

[Anonymous No.9345640]

>>9345637
So something held together so tightly by gravity that all atomic functions have ceased, and only quantum mechanics are preventing it from going further, just barely, can suddenly fly apart because it came into contact with more of the same? How do the neutrons that are packed so close together they are fuxing with the exclusion princple suddenly overcome gravity?

[Anonymous No.9345647]

>>9345623
Why are you so offended? You're the most butthurt I've ever seen a brainlet get after being called out.

[Anonymous No.9345671]

>>9345640
The collision of the two stars broke enough of the neutron matter in them apart into quarks. The rest dispersed as ionising radiation.
>>9345647
Why are you projecting?

[Anonymous No.9345683]

>>9345671
There's not enough energy in the two stars combined to do that - and even if there was - quark degeneracy is just the next layer.

[Anonymous No.9345701]

>>9344388
>if there were such things as white holes we would see them in OUR universe

we dont just see matter popping out of holes in space... unless white holes are the source of ejectae from black holes. and the two singularities coincide together

[Anonymous No.9345702]

this thread

[Anonymous No.9345712]

>>9345701
We don't see matter coming out of nowhere and we don't see black holes shrinking as they would from funneling matter somewhere else. Ergo, matter is staying right where it logically should.

[Anonymous No.9345720]

>>9345701
>>9345712
Think one of the prevailing excuses for that is since the singularity is eternally collapsing, its stretching space away from us at faster than the speed of light. Thus, if there is a white hole on the other side, nothing inside the black hole will ever reach it, and it is no longer part of our universe.

Granted, there are other theoretical ways you can get white holes and wormholes - space should be malleable in this fashion - but it doesn't seem, thus far, that there are any natural phenomenon that can make it happen. (And if any super aliens have found a way to arrange black holes to make it happen, they've not done it close enough for us to notice.)

[Anonymous No.9345723]

>>9345720
>>9345712
aftter a black hole consumes all matter surrounding it, it dissipates over time..soo

[Anonymous No.9345731]

>>9345723
Yes, but that's not because matter or energy is leaving it within that part of the time frame. It does depend on which model of Hawking radiation you use though, as you're either causing an information paradox (stuff being erased), or a causality paradox (energy borrowed from the past), and thus far, no one undone either of those issues in such a way it can be proven - though man, there sure have been some efforts - such as the holographic universe.

[Anonymous No.9345733]

if you can't see the black hole, they should just build a giant flashlight so you can light it up, lmao retarded nerds

[Anonymous No.9345739]

>>9345720
It's not eternally collapsing. There is a singular of mass at the center of black holes, because mass was at the center to begin with.

[Anonymous No.9345743]

>>9345739
No, the singularity collapses infinitely - that's why it's a singularity, nothing to stop it, so it just keeps right on going forever. The spacetime inside becomes timespace, so it's not an issue on the inside, as there, the singularity isn't a place, but a time, and the arrow of time.

[Anonymous No.9345764]

>>9345743
You obviously are taking ideas from different theories and combining them. Yes, there is a singularity of infinite density at the center of blackholes. This singularity formed when the stellar core collapsed on itself. It technically existed before the event horizon formed. Matter that falls into a black hole after the event horizon forms does reach the singularity. To say it doesn't contradicts with your own statement of timespace, wherein the singularity is an inevitable point in time. It's not a point in time that's infinitely far in the future. It's a point in time that matter reaches quite quickly. The streching of space that acts like a conveyer belt inside the black hole will only make a destination impossible to reach if you are going AGAINST it. When going with it, the singularity is right in your face before you know it, and you and the space you are riding on become a part of it briskly.

[Anonymous No.9345782]

>>9345764
>It's not a point in time that's infinitely far in the future.
As I understand it, that's exactly what it is. That's why you get guys Nikodem Poplawski talking about matryoshka doll black hole arrangements forming universes like our own, with our infinitely distant future representing our singularity. I mean, observationally, it doesn't work, in the end, universe being flat and all, but the resulting math could easily take you there.

[Anonymous No.9345808]

>>9345782
That's not how it works according to penrose diagrams. You ever watch PBS Spacetime? Many of the episodes are dedicated to black holes, penrose diagrams and how things are theorised to work. They answer viewer questions about previous episodes at the end of each successive episode. One of the questions was about what we are discussing. It asked if matter ever reaches the singularity. The host (an astrophysics professor who studies quasars) said the answer was yes. Matter does reach the singularity in real time like an apple falling from a tree branch to the ground, from it's perspective. Time dilation effects are never felt by the object experiencing it. As far as the infalling matter is concerned, the time between crossing the event horizon and impacting the singularity is very short (probably a minute to a few seconds), even if we think it's very long from where we are.

[Anonymous No.9345822]

>>9345808
Hrmm... As I had it explained to me, it's not a matter of time dilation but of space stretching at faster than the speed of light as the singularity continues to shrink and thus have ever more local mass, only ceasing to be an issue on the outside of the EH as, due to the fact that the space is moving at faster than the speed of light, the singularity's mass doesn't increase the size of the event horizon where it started, as the ever-increasing gravitational shit never reaches it, but from our perspective, the mass at the event horizon does increase the hole's size.

I find *most* of PBS Spacetime's episodes okay though, so I'll look into it more - as I tend to do for days on end whenever someone comes up with some new crackpot idea. It's always really dicey talking about what happens *inside* the event horizon anyways, in addition to there being, by definition, no way to prove it.

[Anonymous No.9345865]

>>9345822
The way PBS put it for in falling objects was less like space stretching out and more like space acting as a conveyor belt that flows towards the singularity. For something like an outwards traveling photon right at the edge of the event horizon, it works like stretching. The photon is traveling outwards at the speed of light as space travels inwards at the same speed. The photon is doomed to stay orbiting there (in what's called the photon sphere) forever, theoretically. In reality it would soon be knocked in by another photon, or swallowed by the event horizon growing past it.

[Anonymous No.9345903]

>>9345865
Problem I see there is space is not limited to the speed of light, only matter is. If it is true, as I understand it, that the singularity never stops collapsing and nothing can slow it down, it never stops gaining gravitational pull, and in turn, space inside the event horizon around it will continue to stretch forever faster. Space inside the event horizon should be falling at faster than the speed of light, and increasingly faster, the deeper you go, but the singularity and the end of the tunnel grows increasingly distant at the same time as it stretches space - like one of those movie nightmare scenarios, where you try to run towards a door, and the hallway just keeps growing. No matter how fast you run, you're effectively running in place, unable to reach your destination as it fades away in the distance.

Thus, a photon at the very inside edge of the horizon is already moving at faster than the speed of light relative to the outside - which is why it can no longer interact with the outside. Space is moving increasingly quickly the further you "fall" so any group of particles will eventually be separated to the point of inability to interact, similar to the Big Rip scenario in our own universe.

Could be wrong though - tis just what was stuck in my noggin.

[Anonymous No.9346109]

>>9345903
It doesn't work like your first paragraph. If space itself is moving, in falling matter moves with it, in addition to any velocity the matter has that is superimposed on top of space. The gravity of the black hole will provide that velocity. A large amount of it. This is kind of irrelevant, though.

If a photon flies into a black hole dead on, it's going to hit the singularity practically instantly. If it gets captured into orbit, or is emitted perpendicular to the event horizon by in falling matter, then the only destination that would take an infinite time for the photon to reach would be the "infinite future". On this penrose diagram, that situation would be represented by a light ray traveling parallel to the horizon line, upwards and to the right. The diagonal right on this diagram represents the infinite future, while going diagonally left represents your timeline ending at a definite point, which is the singularity.

[Anonymous No.9346135]

>>9345562
this

[Anonymous No.9346205]

>>9346109
There's a reason that line is wavy.

Bugger is, if the singularity is still collapsing, its gravity is increasing, and thus it's still stretching space increasingly, creating more space to travel, at infinite speed. You can't get close to it, as the closer you get, the more distance there is to travel. Sure, you're traveling faster and faster, as space is more and more stretched, but the singularity is stretching that space further, and since it started before you did, is doing it faster than you can ever move towards it.

[Anonymous No.9346233]

>>9346205
Well that's wrong. It's wavy because at r=0, gravity becomes infinitely strong. In other words, it's just represents the singularity, where physics breaks. You're just repeating yourself, too. Rather than doing the same, I'll post the videos which explain how it actually works.

https://www.youtube.com/watch?v=mht-1c4wc0Q

This is a video that will explain penrose diagrams in relation to black holes to you.

https://www.youtube.com/watch?v=KePNhUJ2reI

This is some further extrapolation.

https://youtu.be/Ttwl_zH_DZ8?t=861

This video is not about black holes, but answers some questions about them at the end. I've made a url of the point in the video where they answer the question of whether infalling matter ever becomes a part of the black hole.

https://www.youtube.com/watch?v=-q7EvLhOK08

This just explains the r=0 business of singularities that I was going on about earlier.

[Anonymous No.9346239]

>>9346233
Yes, I get that r=0 infinite gravity, I r saying that's exactly why I've had it explained to me you can never reach it exactly - it's generating infinite space from a point infinitely far in your future. I've seen some of those videos, and the ones I have seen don't contradict that.

But I'll watch the rest and do my damndest to find definitive contradiction when I next get the chance to do so proper.

[Anonymous No.9346375]

>>9345764
>Yes, there is a singularity of infinite density at the center of blackholes.

[Anonymous No.9346377]

>division by 0 is well defined
This thread in a nutshell.

[Anonymous No.9346415]

>>9344317
>really warped space and a singularity

[Anonymous No.9346421]

>>9346415
Brilliant. Not OP btw.

[Anonymous No.9346450]

>>9346375
There is.

[Anonymous No.9346466]

>>9344317
>a lot of matter
>some really warped space
>compressed space
You are really smart OP!

[Anonymous No.9346593]

>>9345415
>When the object is almost frozen, we do have all the confirmation we need that the object has passed the event horizon
This makes no sense. What confirmation if it never actually reaches the horizon?

>For the object's sake, it notices nothing. Time dilation is never felt by the object experiencing it. It would merge with the singularity in real time, from it's perspective.
But it still would take infinite time from outside perspective. The black hole would vaporize before that.
In fact, this also applies to the star itself, it would never actually finish collapsing into black hole. In that sense, black holes really do not exist.

[Anonymous No.9346628]

>>9346593
Not him, but...
>But it still would take infinite time from outside perspective. The black hole would vaporize before that.
Here, you're basically right - though the object falling in won't just freeze, it'll red-shift out of existence - which sure as hell looks like falling in from the outside, even if relativity tells us it never will from our perspective.

>In fact, this also applies to the star itself, it would never actually finish collapsing into black hole. In that sense, black holes really do not exist.
Difference is that the initial formation of the black hole is instantaneous. It's not really that the event horizon swallowed the star, it's that the star became a singularity, and an event horizon of the exact same mass is what's left behind. From our perspective, both happen instantly and at faster than the speed of light. (Cuz again, matter can't do that, but space can.)

[Anonymous No.9346634]

>>9346628
>Here, you're basically right - though the object falling in won't just freeze, it'll red-shift out of existence - which sure as hell looks like falling in from the outside, even if relativity tells us it never will from our perspective.
One problem I have with this description.

Event horizons grow as they gain mass.

Does that not mean, that from our perspective, someone at the event horizon may be completely absorbed by it? In much the way it appears the star was when the event horizon initially appeared?

[Anonymous No.9346639]

>>9346634
I think you're right about that, though generally we're talking about static schwarzschild black holes to simplify matters - real black holes spin, have some charge, and aren't even necessarily perfectly spherical, and all the other incoming matter (and, in the case of quasars, outgoing energy) similarly obscures the view of anything at the event horizon, so other things do come into play.

Though if you combine cosmic censorship and holographic universe theory, I believe it still remains true, even under extreme circumstances such as growing and/or warped ovoid spinning horizons.

[Anonymous No.9346652]

>>9345475
/thread

[Anonymous No.9346654]

>>9346628
>>9346634
Won't it just stay nearly frozen some moments before becoming a singularity (as seen from outside), but never actually becoming one? And any more mass falling in will just make the whole thing bigger, more frozen, closer to singularity but, again, never becoming one?

[Anonymous No.9346669]

>>9346628
>Difference is that the initial formation of the black hole is instantaneous.
It was evaporated by Hawking radiation faster than instantaneous, so no, it didn't make it in time.

[Anonymous No.9346673]

>>9346654
From our perspective - from theirs, they go right in (or, in holographic universe, "encode" on the horizon). Though as >>9346639 pointed out, doesn't apply to growing event horizons that do indeed envelope things, unless, again, talking holographic universe weirdness.

[Anonymous No.9346675]

>>9346669
Takes near forever for a regular (3 solar mass) black hole to evaporate. Only really tiny ones evaporate before heat death of the universe.

[Anonymous No.9346680]

>>9346634
>Event horizons grow as they gain mass.
If event horizon existed, it still wouldn't grow. The process is asymptotic: a condition close to event horizon is difficult to differentiate from true event horizon.

[Anonymous No.9346685]

>>9344477
>interstellar

>>9344373 just gave shit to an entertaingly sappy horror movie, Event Horizon, but the fact that Interstellar was bandied about as being "scientifically accurate" because of Kip Thorne's involvement makes it one of the worst pop sci offenders of all time...

[Anonymous No.9346691]

>>9346680
There are event horizons out there several times larger than our solar systems. Theoretically, they should grow, observationally, they certainly do. Albeit, still smaller than anything with their gravitational mass has a right to be, but still big.

https://i.4cdn.org/wsg/1512560442692.webm

[Anonymous No.9346693]

>>9346691
>There are event horizons out there several times larger than our solar systems.
Go back to >>>/x/

[Anonymous No.9346694]

>>9346675
For black hole it's instantaneous, don't forget time dilation. Also heat death doesn't happen before all black holes evaporate.

[Anonymous No.9346696]

>>9346694
Well, the little ones, yes, will die - but those created from dead stars are generally at least 3 solar masses, and those got several hundred trillion years on them.

[Anonymous No.9346699]

>>9346693
Go back to >>>/flatearth/.

(Seriously, we do need to get these guys who deny basic observations their own board.)

[Anonymous No.9346701]

>>9346699
Great strawman, but you're full of shit and your video is nothing but speculative sci-fi nonsense.

[Anonymous No.9346703]

>heat death
You too. Fuck off. This is a science board, not a science fiction board.

[Anonymous No.9346704]

>>9346691
Its radiation is just very red shifted due to strong gravitation, nothing more.

[Anonymous No.9346705]

>>9346696
>several hundred trillion years
Those will pass instantaneously because of infinite time dilation.

[Anonymous No.9346713]

>>9346705
From the singularity and event horizon's perspective, not from ours and the rest of the universe's.

[Anonymous No.9346718]

>>9346704
That's an interesting idea - not sure how it would work though. Do you have a link to the proposal?

[Anonymous No.9346726]

A black hole is just a very dense object.

[Anonymous No.9346733]

>>9346726
True, if understated, of the singularity - not true of the event horizon. No force or mechanism can hold that much mass up in such a small area, and even if it hypothetically could, the gravitational effects would be quite different.

Not that there aren't some efforts to nix the singularity problem, but this far, they either have no ties to anything testable, or don't mesh with the activity we're seeing out there.

[Anonymous No.9346734]

>>9346713
The result is the same from both perspectives: it evaporates before it does anything.
>>9346718
It's straightforward: as time dilation approaches infinity, frequency of emitted radiation approaches zero, and we have no way to detect the latter.

[Anonymous No.9346739]

>>9346734
>The result is the same from both perspectives: it evaporates before it does anything.
There's no way for a standard black hole to evaporate that quickly.

>It's straightforward: as time dilation approaches infinity, frequency of emitted radiation approaches zero, and we have no way to detect the latter.
That's not how time dilation works, and then there's these concentrated super masses out there, defying all other explanation.

[Anonymous No.9346740]

>>9344337
Hawking radiation doesn't come from the inside.
>>9344462
That's just a shitty popsci explanation, virtual particles don't actually exist, they don't do anything, otherwise the vacuum wouldn't be Lorentz invariant.
>>9344501
>That's not what "observe" means in that context - it means to interact, not "see"
That's also wrong. If interactions were observations you'd never get an interference pattern in the two slit experiment, because the particle has to interact with the slits, otherwise it's like the screen isn't there.
>>9345477
Nope, that guy is correct, everyone reaches the singularity in a finite proper time (that is, time as measured by their own clock, not some guy at infinity). See this question, and the answer by (Nobel laureate) t' Hooft:
https://physics.stackexchange.com/questions/3706/does-any-particle-ever-reach-any-singularity-inside-the-black-hole

[Anonymous No.9346744]

>>9346740
>Nope, that guy is correct, everyone reaches the singularity in a finite proper time (that is, time as measured by their own clock, not some guy at infinity). See this question, and the answer by (Nobel laureate) t' Hooft:
Yeah, but we were talking about the stretching of space inside the event horizon, not the time dilation effect, which, yes, is observer based.

[Anonymous No.9346745]

>>9346740
Indeed it seems that answer address all of the above arguing about time dilation, evaporation happening before you get to fall in, and the incorrect idea of the history of the universe playing out.

[Anonymous No.9346746]

>>9346744
Just read the question, it's about exactly this problem.

[Anonymous No.9346747]

>>9346746
Yes, and the answer isn't explaining that part of the problem.

[Anonymous No.9346751]

>>9346745
>the incorrect idea of the history of the universe playing out.
Still not entirely correct - it'd happen just before you entered the horizon - everything outside would seem to speed up as you neared it.

[Anonymous No.9346752]

>>9346739
>There's no way for a standard black hole to evaporate that quickly.
It takes it less time to evaporate than to collapse, so it evaporates faster than collapses, as simple as that.
>defying all other explanation
How do you register emission of arbitrarily low frequency?

[Anonymous No.9346756]

>>9346740
>virtual particles don't actually exist
Neither do black holes so

[Anonymous No.9346758]

>>9346752
>There's no way for a standard black hole to evaporate that quickly.
It takes exponents of trillions of years to evaporate, and collapses instantly.
>How do you register emission of arbitrarily low frequency?
How do you explain any of these objects?
https://en.wikipedia.org/wiki/List_of_most_massive_black_holes

>>9346756
Virtual particles are merely mathematical artifacts of potential, but those potentials have consequences, hence Hawking radiation. It's just, the short version of the explanation kinda skips that.

[Anonymous No.9346785]

>>9346758
>It takes exponents of trillions of years to evaporate, and collapses instantly.
In different reference frames, time is not invariant.
>How do you explain any of these objects?
>https://en.wikipedia.org/wiki/List_of_most_massive_black_holes
They emit light at low frequencies we didn't figure out how to register.

[Anonymous No.9346786]

>>9346740
>That's also wrong. If interactions were observations you'd never get an interference pattern in the two slit experiment, because the particle has to interact with the slits, otherwise it's like the screen isn't there.
Please don't reinforcing the hollywood pop-sci misnomers further by splitting hairs when you know what he was describing is factually false. You have to interact to take the measurement, anything can do that, be it man or machine, it doesn't mean "see" it in the conventional sense as he is suggesting. It's certainly not that "nothing happens to me as long as no one else sees me" like he's on about.

[Anonymous No.9346790]

>>9346785
>In different reference frames, time is not invariant.
It's very relevant, unless you're traveling at the speed of light. It's the difference between the planet being here, and not being here. Photons don't experience time from their perspective, but we can see they travel over time from our own. A black hole collapsing may not experience time from its perspective, but it sure as hell stays there for us out here.

>They emit light at low frequencies we didn't figure out how to register.
That's not the problem with them - even if the emitted light, they'd still be way too much mass in that small of a space to be supported.

[Anonymous No.9346793]

>>9346758
What happens then? The field consumes energy from black hole, enters an excited state, then creates a pair of quanta?

[Anonymous No.9346801]

>>9346790
>A black hole collapsing may not experience time from its perspective, but it sure as hell stays there for us out here.
That's how infinite time dilation works: evaporation takes finite time for external observer and zero time for black hole - less than collapse.
>too much mass in that small of a space to be supported.
Is there any limit to how much mass can be supported (by whom?)?

[Anonymous No.9346817]

>>9346801
>That's how infinite time dilation works
No, it's not. What happens instantly for a photon does not happen instantly for us. Same with someone sitting in an insanely deep gravity well. Things may seem to be happening faster to him in there, but things are happening same as they always do to us.

>Is there any limit to how much mass can be supported (by whom?)?
If there wasn't, stars would never die. They are being held up by fusion reactions, and once they run out of hydrogen and get to down to iron, that quickly ceases to be the case. Then the core collapses into a neutron star held up by degeneracy pressure, while it fux with the one thing that keeps any two fermions from occupying the same space - namely the pauli exclusion principle.

If it takes on any more mass beyond that point (or just had it to begin with, should the core have been large enough), the energy potential of the neutrons becomes high enough that they begin to bond with their oppositely charged pairs, much like electrons pair up in superconductors, and at that point, they are no longer fermions, but bosons. Bosons can occupy the same point in time space, so once that process starts, everything is only going to get more and more concentrated, until there is nothing left that can hold that mass back - and it just collapses infinitely.

For this reason, nothing can hold more than 3 solar masses in the space about the size of our moon, without collapsing on itself.

[H No.9347113]

>>9346786
He's still completely wrong, though. He's just as wrong as the guy he's replying to: measurement is NOT the same as interaction.

[H No.9347128]

>>9346793
The vacuum (that is, field theory ground state) at the horizon of the black hole isn't the same as the vacuum of the guy infinitely far away, so the ground state that one says has no particles the other says has particles. This is essentially the same as the Unruh effect.

[Anonymous No.9347264]

>>9347113
True, though it's also not the same as "observing" in the colloquial sense.

We really need a better term, so people don't get to thinking quantum woo proves dogs have souls cuz they collapse waveforms n'shit.

[Anonymous No.9347269]

>>9344363
"Einstein" you illiterate fag.

[Anonymous No.9347275]

>>9346740
>virtual particles
not virtual
not particles

https://profmattstrassler.com/articles-and-posts/particle-physics-basics/virtual-particles-what-are-they/

[Anonymous No.9347278]

>>9344328
>gluing two black holes together
so simple

[Anonymous No.9347305]

>>9347275
Speaking of needing better terms... We're reaching HRE levels here.

[Anonymous No.9347516]

>>9345565
>but CERN's been doing a lot of odd things that have been John Snow'ing us for awhile.
For example?

[Anonymous No.9347530]

>>9345562
PBS Space Time is popsci that teaches factual things at a high level in an interesting and clear manner. Most other popsci is a bunch of bullshit for people to pretend they have university level understanding of things while not actually understanding anything.

[Anonymous No.9347541]

>>9345587
Not him, but I think you ignored the most important part of what he said, which is "superficial". I personally find this to be sort of dishonest curiosity, one where you don't actually care at any level and have it simply for some base egotistical reason, like impressing others with your "knowledge".

[Anonymous No.9347892]

>>9346747
It does if you can put 2 and 2 together. The fact that an evaporating black hole spews out nothing but light should tell you that matter does reach the singularity. If it didn't, it would pop back out, whitehole style. Blackholes don't create regions of infinite space within themselves, according to literally every physicist you ask.

[Anonymous No.9347898]

>>9346634
>someone at the event horizon

MATTER DOES NOT STAY AT THE EVENT HORIZON. WE JUST NEVER SEE THINGS CROSS IT BECAUSE THE LIGHT FROM THE CROSSING CAN NEVER REACH US. GET THIS THROUGH YOUR FUCKING HEAD.

[Anonymous No.9348098]

>>9347898
Is there not also a relative time dilation effect to consider?

[Anonymous No.9348104]

>>9344331
>atlas

[Anonymous No.9348113]

>>9344826
>earth in pic is round

[Anonymous No.9348146]

>>9348113
It's an exaggerated ma... Oh, oh... I see what you're doin there.

[Anonymous No.9348575]

>>9348098
If you're sitting outside the event horizon watching a clock fall in, you will never see the clock reach the event horizon. You will see the clock slow as it approaches the horizon and you'll see it running slower and slower. However there is no point in which time stops at the event horizon. You can wait as long as you want, and you'll see the clock creep closer and closer, but time will continue for both you and the clock.

Now suppose you're holding the clock. Assuming you can survive the tidal forces you'll cross the point where an external observer thinks the event horizon is (you would see no horizon there, the only way to tell is to look up and see that the only light source is directly above you, since all other light is bended away) and you would hit the singularity in a finite time. All the while, the clock in your hand would tick normally, until you reach the singularity.

At the singularity the spacetime curvature becomes infinite and there is no way to calculate your path in spacetime past this point. This is known as geodesic incompleteness (annoyingly Wikipedia has no good article on this but Google "geodesic incompleteness" for lots of info on the subject). It's because there is no way to calculate your trajectory past the singularity that it is said that spacetime stops there, at the singularity. Note that it's not just "time", but "space-time". Your worldline ends, but at the singularity, not before.

[Anonymous No.9348728]

>>9347898
>>9348575
Well then he's right, from the outside perspective, the matter never goes in.

I get that clocks are local - that the matter goes in just from from the matter's perspective, but from us out here - it's not gonna happen until, like the guy said, the horizon grows to envelope the point at which we think he should be.

[Anonymous No.9348858]

>>9348728
>from the outside perspective the matter never goes in

Only for a Schwarzchild, eternal black hole. General Relativity gives us a way to describe the universe that is independant of any frame of reference. However for us observers to calculate what we see, we have to do the calculations in our frame of reference i.e. in meters and seconds that we can measure. The static black hole is described by the Schwartzchild metric, and it's not hard to use this to calculate things like how long it takes to fall onto the event horizon. One common co-ordinate system is co-moving co-ordinates i.e. the observer falling into the black hole measures distances from himself (putting himself at the origin) and time on the stop watch he's carrying. If you do this calculation you find the observer falls through the event horizon in a finite time, and in fact hits the singularity at the centre of the black hole in a finite time.

But where things get odd is we calculate the time taken to reach the event horizon in our co-ordinate system as observers sitting outside the black hole. The answer is that it takes an infinite time to reach the event horizon.

At this point someone will usually pop up and say that means black holes don't really exist. In a sense that's true in our co-ordinate system, but all that means is that our co-ordinate system does not provide a complete description of the universe. In the co-ordinate system of the freely falling observer the event horizon does exist and can be reached in a finite time.

It does go in. You just don't see it go in. You see it freeze and then fade out as it becomes infinitely red-shifted. The time between each photon arriving at your position becomes greater and greater, but there is never an end to the number of photons, for an eternal black hole. For a modern interpretation of the black hole that takes hawking radiation into account, you will eventually in the distant future get the last photon.

[Anonymous No.9349218]

>>9348858
If you're trying to say that his apparent freezing and red shifting is just an artifact of light, this isn't entirely the case. That's a side effect of gravity curving space that has consequences for both the man close to the event horizon and the outside universe. Much as he will appear to slow and eventually freeze from the outside perspective, the outside universe will appear to speed up from his.

If he has a magical rocket ship that can travel near-c, and escapes the pull of the event horizon before entering, long after having vanished from the outside perspective, the amount of exceptionally curved space he will have to travel will leave him significantly far in our future when he finally arrives at the point where we were earlier observing him from.

Now, if he *teleports* to where we are viewing him from instead, this will not be the case, but he will have effectively traveled back in time to do so and violate causality along the way, having seen our future. Which is among the reasons FTL (ie. faster than causality) is not allowed.

[Anonymous No.9350351]

>>9349218
Wormholes are not forbidden by physics. As such it is theoretically possible to travel to the future by sticking one end of the wormhole near a black hole and the other in flat space.

You may also time travel forwards at an accelerated pace by just moving really fast for a long time.

[Anonymous No.9350352]

>>9344317
>Where did this crap come from?

shitty math.

[Anonymous No.9350364]

>all these faggots arguing about sci-fi world-building details
Hilarious

[Anonymous No.9350368]

>>9344317
Like a box in a box

[Anonymous No.9350394]

>>9350351
You, technically, don't travel faster than light through wormholes, as it's warped space that allows it, though yes, they could result on causality violations. Mind, so far, it appears they don't happen anyways.

>You may also time travel forwards at an accelerated pace by just moving really fast for a long time.
The potential causality violation the time dilation effect that results from traveling near C has is countered by the time and energy it takes to turn around, go back, and meet your now older twin. Beyond that, time slowing down for you relative to everyone else isn't a problem. Different reference frames intersect at each other's past and future at sufficient distances, even at walking speed, but the distances involved require FTL communication, in both directions, to cause causality issues.

[Anonymous No.9350472]

>>9350394
In the case of traveling really fast, there's no reason one can't travel fast in circles, close to something not moving fast.

[Anonymous No.9350572]

>>9345589
>ou can't make neutron degeneracy pressure to hold them up without emitting a whole lotta radiation.

So neutron stars are perpetual motion machines that can perform net work?

[Anonymous No.9350581]

Guys, guys, if a black hole has a singularity of infinite density and thus zero volume at its center, what's to stop that singularity from quantum-tunneling to anywhere else in the universe?

[Anonymous No.9350594]

>>9350572
They are powered by gravity and mass, like every other small star and brown dwarf with near a immeasurable lifespan.

[Anonymous No.9350597]

>>9350581
shut the fuck up

[Anonymous No.9350598]

>>9350581
I... Dun think that's how that works (and yer probably trolling)... But there's no potential for anything to leave the event horizon, so even if it did work that way, wouldn't be a problem.

[Anonymous No.9350600]

>>9344317
Steven Hawking. There isn't a theory about black holes crazy enough for him.

[Anonymous No.9350611]

>>9350472
It is a problem for something with mass, but that also mitigates the dilation effect. It's about the speed two objects are moving relative to each other, so if one is circling the other, it's not going to be able to communicate with a time discrepancy much larger than something else in that same stationary orbit, and that discrepancy will be in the same timewise direction, going both ways.

[Anonymous No.9351016]

>>9350611
Absolutely wrong. Astronauts and satellites in orbit travel faster into the future than people on earth. GPS systems have to account for this.

[Anonymous No.9351030]

>>9344317
I like to thing black holes are just anomalies of a distinct lack or anything, that's why they suck stuff in

Like, when a balloon underwater pops, water rushes in to fill the space of the air (ignore the fact that once trapped air floats upward)

Matter flows into the black hole to fill the space

[Anonymous No.9351125]

>>9345671
This is an AI that's learned to shitpost.

[Anonymous No.9351232]

>>9350594
So that is a yes, in your understanding of physics, they violate the laws of thermodynamics. Not that believing in this sort of quackery is surprising or anything, given how you believe gravitational singularities exist and all that.

[Anonymous No.9351234]

>>9350581
The fact that it doesn't exist.

[Anonymous No.9351244]

>>9351016
Like I said...
>it's not going to be able to communicate with a time discrepancy much larger than something else in that same stationary orbit
It has more to do with depth in the gravity well than the speed differential.

[Anonymous No.9351248]

>>9351232
Stars do not violate the laws of thermodynamics, a lot of mass in one place has inherent sustainable energy due to potential - the smaller the star, the slower it burns through that potential, and neutron stars and white dwarves are the smallest stars around. Though neutron stars do like to fux with the pauli exclusion principle some, and yes, black holes fuck with thermal dynamics in fundamental ways people have been trying to compensate against for decades. But every law of thermal dynamics breaks down under one extreme circumstances or another, and black holes are about the most extreme circumstance around.

[Anonymous No.9351255]

>>9351248
>black holes are about the most extreme circumstance around.
Indeed: >>9346377

[Anonymous No.9351575]

>>9344364
White holes exist. Only, they're invisible, intangible and not located somewhere we can find them.

[Anonymous No.9351683]

>>9344373
>hating Event Horizon

Oookay...

[Anonymous No.9351686]

>>9344801
>Now tell him about vacuum energy and how space isn't actually nothing.

I need this for a friend. Can you point me to an article on the subject, please?
Or should i just print wikipedia?

[Anonymous No.9351721]

>>9344363
>Eisenstein
Eesensteen

[Anonymous No.9351887]

>>9351248
>fux
I've read this whole thread and always imagined you using the word fux as some sort of autistic quirk as not to write "fucks".
what does it mean?

[H No.9351903]

>>9345557
>that the experimenters claimed was shown to radiate an optical analog to Hawking radiation
>an optical analog to Hawking radiation
> a n a l o g ( u e )

[Anonymous No.9351904]

>>9351887
You got it exactly right. He is a reject from some other site self-censoring himself like a retard.

[H No.9351905]

>>9347278
I didn't say it was likely, just that it's a very simple modification of the normal black hole geometry and is a perfectly valid solution to the EFEs.

[Anonymous No.9351907]

>>9351904
>self-censoring himself
Please excuse the pleonasm.

[Anonymous No.9351941]

>>9351686
https://www.youtube.com/watch?v=X5rAGfjPSWE

[Anonymous No.9351976]

>>9351907
Good word
Thank you

[Anonymous No.9352338]

>>9344338
>tfw your calculations aren't making sense so you blame it on multiple demonizes that no one can verify and you claim anyone who isn't down with your bs is a religious zealot

[Anonymous No.9352605]

>>9344436
I literally spilled by drink from laughing.
You take the cake for the most idiotic thing ive read on this site.