what is black hole made out of and what does a black hole "experience"?

[Tormod]

Originally posted by: BlameTheEx
The argument for Black Holes goes that although particles are apparently accelerated to greater than C within the Singularity, it does not count, as the inside of a Singularity is not part of the universe.

No offense, Blame, but I think you are confusing the terms black hole and singularity. The black hole in itself has a dimension and size. If our own sun were to collapse and form a black hole it would be just a few kilometers across.

The singularity resides at the heart of the black hole and has no dimension and no size, although it has infinite density (which is a rather meaningless term). So while technically the black hole has an "inside" and a "surface", the singularity does not.

As applied to Black Holes, it defines the point of no return.

That is called the event horizon.

[BlameTheEx]

Tormod

Hmmm. You may be right. I guess I should do more checking.

Aki.
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wouldn't the escape velocity be greater than C?
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Err. You are asking for more details on something I don't actually believe in, but I will do my best.

First, nothing can escape from a body with an Escape velocity of C or above. C is sufficient, but perhaps you are asking if it can get higher? Tricky question.

Best I can figure it the answer is no, even if I am wrong, and Black Holes exist. The reason is rather interesting. At the point which I think Tormod is accurately calling the event horizon, time dilation is total. Nothing can go further, or faster because there is no time for it to happen in.

[Aki]

Well this is what I'm thinking, and I'm probably wrong:
if the escape velocity is C, then wouldn't light be able to escape? So shouldn't the escape velocity be greater than C?

[BlameTheEx]

Aki

Well, light would escape, and it wouldn't.

An escape velocity of C would result in a red shift of infinity. The light would escape, but with a frequency of zero hertz, and an energy of zero electron volts! In short it will disappear entirely. Nothing gets out except the idea of a photon.

[Freethinker]

Originally posted by: Tormod
So while technically the black hole has an "inside" and a "surface", the singularity does not.

That is called the event horizon.

I think it might be more accurate to refer to the Event Horizon as a "Boundary", not a "surface".

[Aki]

Originally posted by: BlameTheEx
Aki

Well, light would escape, and it wouldn't.

An escape velocity of C would result in a red shift of infinity. The light would escape, but with a frequency of zero hertz, and an energy of zero electron volts! In short it will disappear entirely. Nothing gets out except the idea of a photon.

Ah okay, I get it now

[BlameTheEx]

Tormod.

Done my checking. You are right. Event horizon is correct, and Singularity isn't.

Thanks.

[Tormod]

Originally posted by: Freethinker

I think it might be more accurate to refer to the Event Horizon as a "Boundary", not a "surface".

I did not say the event horizon has a surface. The black hole has a "surface", the event horizon is the boundary which Blame correctly labeled the "point of no return". I think however that for all practical purposes they are one and the same.

The "point of no return" idea is true no matter what happens, even if we see particles escaping. When, say, a proton reaches the horizon it will decay into smaller parts, some of which will fall into the black hole, while some will "miss" it. The original particle is nevertheless destroyed by the interaction. this is, however, true for *all* events in quantum physics.

I found an interesting (not too technical) read on black hole formation:

The Formation and Growth of Black Holes
http://www.mathpages.com/rr/s7-02/7-02.htm

[paultrr]

Has anyone else ever noticed that the zero point out of quantum physics shares a lot in common with a blackhole state? Granted the gravity context is different. But zero time type background frame still applies.

[paultrr]

Basically, backing up another post with the words, "this is, however, true for *all* events in quantum physics."