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The strange fate of a person falling into a black hole

bbc.com

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Re: The strange fate of a person falling into a black hole

#11

Post by repsilat »

>there is no paradox, because no one person ever sees your clone. Anne only sees one copy of you. You only see one copy of you. You and Anne can never compare notes.

Can't you? Why can't Anne "gather up your ashes" and send them into the black hole, where you can inspect them? Shouldn't that go against the "no cloning theorem"?

Re: The strange fate of a person falling into a black hole

#13

Post by tfgg »

guard-of-terra wrote: post #6
thomasahle wrote: post #3

Earlier quoted context omitted.

Well, it has to be slightly more complicated than that. After all you are going to be emitted as hawking radiation a lot earlier than the end of the universe.

Large black holes have life expectancy so much larger than universe age that it's not even funny. They're not going anywhere AFAIK. No, you will stay there and watch. "The power in the Hawking radiation from a solar mass black hole turns out to be a minuscule 9 × 10−29 watts. It is indeed an extremely good approximation to call such an object 'black'."

Larger than the current life of the universe, not necessarily longer than the end of the universe, though that really depends on your model of how it'll all end. Some do involve black holes gradually boiling away to radiation being the last things being left.

Re: The strange fate of a person falling into a black hole

#14

Post by kagamine »

repsilat wrote: post #11

>there is no paradox, because no one person ever sees your clone. Anne only sees one copy of you. You only see one copy of you. You and Anne can never compare notes. Can't you? Why can't Anne "gather up your ashes" and send them into the black hole, where you can inspect them? Shouldn't that go against the "no cloning theorem"?

Given the initial split in realities, Anne would create a new parallel universe when she placed your ashes in the black hole, one in which they exist outside the black hole and in a parallel universe where they exist inside the black hole, but this is not the same parallel universe you are experiencing, but a parallel parallel universe. Essentially, 2 instances of the black hole.

Re: The strange fate of a person falling into a black hole

#15

Post by antimagic »

Varkiil wrote: post #12

"In a big enough black hole, you could live out the rest of your life pretty normally" Free falling in your ship and suit waiting for you to be crushed to death... pretty normally

It depends on what you mean by "inside" a black hole. If this means "inside the event horizon", well, if the black hole is big enough, you can put yourself in orbit around it relatively easily, you'll just never be able to achieve escape velocity. If you take the Earth for example, a geosync orbit has a velocity of 3.07km/s, whereas escape velocity is 11km/s

Re: The strange fate of a person falling into a black hole

#16

Post by nikbackm »

Varkiil wrote: post #12

"In a big enough black hole, you could live out the rest of your life pretty normally" Free falling in your ship and suit waiting for you to be crushed to death... pretty normally

Assuming you still have an internet connection... why not? :)

Well, guess TCP/IP is out, but maybe TV and radio broadcasts would still function.

Re: The strange fate of a person falling into a black hole

#19

Post by BenderV »

"That's the thing about black holes. They're not just annoying obstacles for space travellers. They're also theoretical laboratories that take the subtlest quirks in the laws of physics, then amplify them to such proportions that they can't be ignored."

I also use this strategy to think about philosophy and science. People often think that because they are extremes, they are not relevant. However, they are as relevant! And they force us to think outside our natural instinct.

Re: The strange fate of a person falling into a black hole

#20

Post by dvdkhlng »

antimagic wrote: post #15
Varkiil wrote: post #12

"In a big enough black hole, you could live out the rest of your life pretty normally" Free falling in your ship and suit waiting for you to be crushed to death... pretty normally

It depends on what you mean by "inside" a black hole. If this means "inside the event horizon", well, if the black hole is big enough, you can put yourself in orbit around it relatively easily, you'll just never be able to achieve escape velocity. If you take the Earth for example, a geosync orbit has a velocity of 3.07km/s, whereas escape velocity is 11km/s

There aren't any stable orbits within the event horizon of a black hole (due to General Relativity):

https://en.wikipedia.org/wiki/Schwarzschild_metric#Orbital_m...

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