At the center of a black hole is it the same time as the moment of its formation?

[Lancer]

Having trouble understanding black holes.

[Blake]

As far as I understand it, things will appear, to an external frame of reference, to "freeze" as they hit the event horizon, BUT that's only because of the speed of light - from THEIR frame of reference, they fall in just fine.

It might be reasonable to say that from an external frame of reference, it's always the same time in a blackhole, but not from an internal (unsafe) frame of reference. But I'm not a blackhole theorist.

Incidentally, it is theoretically possible to fall through an event horizon unharmed, but you can never escape and good luck with the singularity

[DRoseDARs]

Fry: Don't cry, Bender. No one really knows what happens in a black hole. She could still be alive in another dimension somewhere. Right, professor?
Professor Hubert Farnsworth: Oh, sure. Absolutely.
Professor Hubert Farnsworth: [Whispers to Zoidberg] Not a chance. [Mimes slashing his throat and being hanged]

[KrazyHorse]

Originally posted by Blake
As far as I understand it, things will appear, to an external frame of reference, to "freeze" as they hit the event horizon, BUT that's only because of the speed of light - from THEIR frame of reference, they fall in just fine.

a) It's not because of "the speed of light"; it's a general relativistic effect.

b) They haven't had time to fall through yet. In fact, from any sane perspective it's hard to explain how a black hole can form in finite external time. AFAIK it's possible that there are no black holes. Only objects which are almost black holes.

[Heraclitus]

Or that the actual "structure" of the black hole might be substantially different from calssical interpretation. Perhaps finding new interesting possiblities for what we theoretically know of Hawking radiation. There are a few very interesting recent theories on the matter.

[KrazyHorse]

Hera, can you please state what training you have received which allows you to comment on whether "recent developments" in a field so badly understood as quantum field theory in strongly curved space are interesting?

Thanks in advance.

[Ecthy]

I'd rather we take a look at the sad, black whole.

[Elok]

While we're asking clueless physics questions, how does gravity fit into the whole no-work-without-energy bit? I mean, if you need to expend energy to move objects...does the universal effect of gravitation have some sort of "power source," or is it exempt from the usual rules somehow, or is it one of those things we don't know yet? Yeah, I feel really dense asking this, especially since I don't know any of the proper terminology.

[Heraclitus]

Originally posted by KrazyHorse
Hera, can you please state what training you have received which allows you to comment on whether "recent developments" in a field so badly understood as quantum field theory in strongly curved space are interesting?

Thanks in advance.

I’m a bloody physics student! But I do admit that I know very little compared to someone already holding a PhD on the subject or doing active research.

I do feel that I know much, much more than a simple high school science teacher, but please note that I am not implying this is particulary hard to achieve.


Now unless you are a theoretical physicist, I doubt it very much that your comment was appropriate, and expect an apology.


If you by some freak chance you are, and not just a happy camper who read The Universe in a Nutshell and now thinks he dosen't need to understand the mathematical underpinning of the complex theories in order to properly debate them, I concede to your point.


EDIT: wtf poly, what are the bloody odds? The phrase of having to eat one's words gains a whole new meaning.

[KrazyHorse]

a) In the non-relativistic sense you can view the gravitational field as a means to store energy. Two pointlike massive objects m1 and m2 seprated by r have potential energy due to gravitation -Gm1m2/r (using infinty as the zero point). Changes in their configuration lead to transfer from the potential energy in the gravitational field to kinetic energy (or some other form)

b) In general relativity in a global sense energy is not conserved. You can define some local quantities which conserve "energy" but in general these are not as useful as global energy conservation is classically

[KrazyHorse]

Originally posted by Heraclitus
Now unless you are a theoretical physicist

Should I tell him or does somebody else want to?

[Heraclitus]

Originally posted by KrazyHorse




Should I tell him or does somebody else want to?

You have got to be kidding me.

[Donegeal]

Originally posted by KrazyHorse




Should I tell him or does somebody else want to?

Why would we do it when you like tooting your own horn so much?

(Welcome back, BTW)

[Heraclitus]

Originally posted by Donegeal


Why would we do it when you like tooting your own horn so much?

(Welcome back, BTW)

It's true?!

[KrazyHorse]

YOU ARE ENTERING A WORLD OF PAIN