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First proof that "plunging regions" exist around black holes in space

ox.ac.uk

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Re: First proof that "plunging regions" exist around black holes in space

#31

Post by knodi123 »

sliken wrote: post #21
jl6 wrote: post #16

Earlier quoted context omitted.

Publish and perish.

No need to perish, current theories explain that the innermost region of a spinning black hole (all real world black holes spin) has a low gravity region where arbitrary navigation is possible. You can't escape, but you also don't have a death date with the singularity.

Uh... But how do you get there? My understanding as a lay-person is that you can't get past the event horizon without getting spaghettified, and cooked by high-energy blue-shifted radiation.

Re: First proof that "plunging regions" exist around black holes in space

#32

Post by Vampiero »

card_zero wrote: post #20
bisby wrote: post #7

Earlier quoted context omitted.

No one mentioned LLMs. We know that there are things that computers can flat out do better than humans, because there are limits to human brains. If computers continue to grow in power, then the fact that someday there might be an AI (actual AI, not LLM) which can come up with novel solutions is totally plausible. And if we go past that point and computers continue to become more powerful, then it's likely that the A…

None of that is fact, or inevitable, or meaningful. What are "thinking capabilities", what are they made of? More RAM? A human can have more RAM, by installing it in the human's computer. More parallelism? Maybe, but that's like having more humans. More speed? It's not clear what you'd do with it, since research tends to involve interaction and the outside world has a pace of its own: sitting in a cell on amphetamine…

I'd agree with what you're saying, but the jump to "not believing in superintelligence" doesn't make sense either. Are you implying that humans are the absolute peak of intelligence or that computers can't ever achieve something that is even just one iota better than human-level intelligence?

There's one thing machines have that we don't: time. A human-level AI would be better than a human because you can ask it to solve a problem for years on end without ever resting.

Re: First proof that "plunging regions" exist around black holes in space

#33

Post by knodi123 »

pests wrote: post #14
ganzuul wrote: post #11

Why is it that some experts say stuff falls into the center of a black hole while others say it slows down and never passes the event horizon? Is it just semantics?

Frame of reference. The object falling in experiences time as normal and actually falls in. From an outside observer they never cross the event horizon, due to the time dilation mentioned by the other comment.

> From an outside observer they never cross the event horizon, due to the time dilation mentioned by the other comment.

Doesn't that imply that if we look at a black hole from a safe distance, the event horizon will appear to be a cluttered frozen motionless ring, full of all the stuff that is in the process of falling in but which from out point of view, never will?

Re: First proof that "plunging regions" exist around black holes in space

#34

Post by csomar »

vbezhenar wrote: post #5
gigatexal wrote: post #2

Still continues to amaze me that the more they look the more they confirm Einstein. Yet we know — or strongly suspect — that at the singularity and within the BH general relativity breaks down. I hope we see a unification of GR and Quantum mechanics in my lifetime. Would be really neat

Is it even scientific to claim anything about black hole insides? AFAIU it's impossible by definition for any information to escape black hole insides. Any observation or experiment is not possible. Any assumption can't be confirmed or rebuted. Basically it can't be falsified, so it's not a science according to Popper.

Maybe if you can create nano-blackholes and explode them later in a controlled fashion?

Re: First proof that "plunging regions" exist around black holes in space

#35

Post by sliken »

knodi123 wrote: post #31
sliken wrote: post #21

Earlier quoted context omitted.

No need to perish, current theories explain that the innermost region of a spinning black hole (all real world black holes spin) has a low gravity region where arbitrary navigation is possible. You can't escape, but you also don't have a death date with the singularity.

Uh... But how do you get there? My understanding as a lay-person is that you can't get past the event horizon without getting spaghettified, and cooked by high-energy blue-shifted radiation.

Getting past the event horizon of a small blackhole is tough, the gravitational gradient causes spaghetification. However larger blackholes lessen the gradient at the event horizon, so it's not a problem.

Not sure about the inner horizon, just saw a discussion of the paper for a spinning black hole recently, it described three distinct regions.

Re: First proof that "plunging regions" exist around black holes in space

#36

Post by DonHopkins »

af78 wrote: post #19
cdchn wrote: post #3

Earlier quoted context omitted.

Not to bring the all pervasive AI topic into this discussion, but I think the best hope we have for finding that unification depends on an AI superintelligence. I wonder if we've reached the limit of what a singular human mind can push.

AI or not, if a machine finds an answer so complex that no human can understand it, how useful is it?

Or an answer so simple: 42.

Re: First proof that "plunging regions" exist around black holes in space

#37

Post by squrky »

sliken wrote: post #21
jl6 wrote: post #16

Earlier quoted context omitted.

Publish and perish.

No need to perish, current theories explain that the innermost region of a spinning black hole (all real world black holes spin) has a low gravity region where arbitrary navigation is possible. You can't escape, but you also don't have a death date with the singularity.

My layperson understanding is that collision with the singularity (if that even exists) is mathematically inevitable for an object that has crossed the event horizon. I think your scenario of hanging out within the event horizon and safely away from the singularity for indefinite time would require infinite fuel to counteract the gravitational gradient, or for even more fundamental reasons.

Re: First proof that "plunging regions" exist around black holes in space

#38

Post by pests »

knodi123 wrote: post #33
pests wrote: post #14

Earlier quoted context omitted.

Frame of reference. The object falling in experiences time as normal and actually falls in. From an outside observer they never cross the event horizon, due to the time dilation mentioned by the other comment.

> From an outside observer they never cross the event horizon, due to the time dilation mentioned by the other comment. Doesn't that imply that if we look at a black hole from a safe distance, the event horizon will appear to be a cluttered frozen motionless ring, full of all the stuff that is in the process of falling in but which from out point of view, never will?

Almost, another detail is the closer the object gets to the event horizon, the more it's light redshifts - until it's no longer in the visible spectrum at all. You can think of the black hole's gravity as stealing energy from the light, shifting it into a lower energy spectrum.

Re: First proof that "plunging regions" exist around black holes in space

#39

Post by cjfd »

vbezhenar wrote: post #5
gigatexal wrote: post #2

Still continues to amaze me that the more they look the more they confirm Einstein. Yet we know — or strongly suspect — that at the singularity and within the BH general relativity breaks down. I hope we see a unification of GR and Quantum mechanics in my lifetime. Would be really neat

Is it even scientific to claim anything about black hole insides? AFAIU it's impossible by definition for any information to escape black hole insides. Any observation or experiment is not possible. Any assumption can't be confirmed or rebuted. Basically it can't be falsified, so it's not a science according to Popper.

It looks like they are mostly making statements about what is happening outside the Schwarzschild radius. These are testable statements.

Re: First proof that "plunging regions" exist around black holes in space

#40

Post by ben_w »

af78 wrote: post #19
cdchn wrote: post #3

Earlier quoted context omitted.

Not to bring the all pervasive AI topic into this discussion, but I think the best hope we have for finding that unification depends on an AI superintelligence. I wonder if we've reached the limit of what a singular human mind can push.

AI or not, if a machine finds an answer so complex that no human can understand it, how useful is it?

I don't see that as being an important objection, because from the point of view of any single human… that's already true for the expertise found only in other humans.

I don't know the chemistry necessary to turn crude oil into any plastic, I don't know how to use a Lagrangian, I tried and failed to learn group theory (I've only got the basics, and I'm not confident about them), and I've still only got a toy model of special relativity (which is supposed to be the easier one) — and yet, not only are those all still useful, the four colour theorem is useful even though it's a non-surveyable proof: https://en.wikipedia.org/wiki/Non-surveyable_proof

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