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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

#71

Post by tbrownaw »

cdchn wrote: post #3
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

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.

> I wonder if we've reached the limit of what a singular human mind can push.

We passed that limit ages ago. The underlying technology used to do so is called "writing", which is what allows for things like libraries and letters / email and personal scratchpad notes.

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

#72

Post by golem14 »

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.

I always wondered if you can orbit inside the event horizon of a large black hole and wait until its hawking radiation shrinks the event horizon so that you find yourself outside. You would have to wait a long time I guess.

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

#73

Post by idiotsecant »

BurningFrog wrote: post #69
squrky wrote: post #37

Earlier quoted context omitted.

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.

You can orbit a black hole like any other gravity source, without spending fuel. I don't know how near the event horizon a safe orbit can be?

That's kind of the definition of the event horizon. You cannot be 'safe' once you're inside. All paths lead to the event horizon. No matter which direction you point, you're pointed at it.

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

#74

Post by idiotsecant »

rthnbgrredf wrote: post #65
santoshalper wrote: post #53

Earlier quoted context omitted.

Yes, but definitionally, none of those experiments can tell us anything about what is inside the black hole.

Well, we have a pretty good understanding of how our sun works internally just by observing it from the outside, without ever digging a hole into it to observe it from the inside.

That's because the sun emits a great deal of information. Black holes by definition emit none (on human time scales)

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

#75

Post by bongodongobob »

dotnet00 wrote: post #55
vbezhenar wrote: post #5

Earlier quoted context omitted.

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.

From my understanding, that invokes the black hole information paradox. There should be some way in which the information of what went into a black hole is retained, a possible answer being with the Hawking radiation. We just don't know enough about black holes to say for sure that the insides can not be studied in some manner. That's kind of why a theory of quantum gravity is so relevant, without it, the inaccessibi…

Using information from Hawking Radiation to understand what went in: while it might be possible, isn't this on the same practical level of unscrambling an egg? Sure we could do it with nanobots but is that really a possibility or just a mathematical curiosity?

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

#76

Post by woopsn »

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?

There is also a theory that as you approach the horizon you'll be incinerated by a kind of hidden firewall. This apparently contradicts GR - but on the other hand if you're allowed to fall in it seemingly contradicts QM.

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

#77

Post by dotnet00 »

bongodongobob wrote: post #75
dotnet00 wrote: post #55

Earlier quoted context omitted.

From my understanding, that invokes the black hole information paradox. There should be some way in which the information of what went into a black hole is retained, a possible answer being with the Hawking radiation. We just don't know enough about black holes to say for sure that the insides can not be studied in some manner. That's kind of why a theory of quantum gravity is so relevant, without it, the inaccessibi…

Using information from Hawking Radiation to understand what went in: while it might be possible, isn't this on the same practical level of unscrambling an egg? Sure we could do it with nanobots but is that really a possibility or just a mathematical curiosity?

Given the amount of mass typically involved, probably just a mathematical curiosity, but if that's the only way we can figure out to try to understand the inside, maybe we'll eventually be able to generate microblackholes from tiny amounts of matter, collect the hawking radiation and study those in this manner (they'd evaporate pretty quickly).

Edit: I forgot to add in my original post that there's also just the possibility that the mechanism by which this paradox is resolved still hides the inside.

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

#78

Post by cdchn »

klyrs wrote: post #4
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.

> I wonder if we've reached the limit of what a singular human mind can push. You people are becoming zombies. Get away from your computer and interact with the world. Humans with profound intellect are producing the content that LLMs regurgitate for you.

The idea for me comes less from AI than the slowdown, I think, of really ground breaking science. We're still proving Einstein's ideas, we haven't really moved much beyond Einstein.

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

#79

Post by cdchn »

klyrs wrote: post #4
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.

> I wonder if we've reached the limit of what a singular human mind can push. You people are becoming zombies. Get away from your computer and interact with the world. Humans with profound intellect are producing the content that LLMs regurgitate for you.

Thats the distinction I think between an LLM and a real AGI. One is a stochastic parrot, the other can come up with new ideas.

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

#80

Post by [deleted] »

dotnet00 wrote: post #55
vbezhenar wrote: post #5

Earlier quoted context omitted.

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.

From my understanding, that invokes the black hole information paradox. There should be some way in which the information of what went into a black hole is retained, a possible answer being with the Hawking radiation. We just don't know enough about black holes to say for sure that the insides can not be studied in some manner. That's kind of why a theory of quantum gravity is so relevant, without it, the inaccessibi…

[deleted]
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