Re: Event horizon questions?

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Posted by egibbs on May 14, 2002 at 08:26:30:

In Reply to: Re: Event horizon questions? posted by DickT on May 13, 2002 at 20:13:23:

Dick,

I think it's a bit more complicated than that if you really look carefully.

For one thing, the radial (inward) dimension becomes timelike once you cross the Event Horizon. The singularity lies not at a point in space at the center of the Black Hole, but rather at the "End of Time" inside the Black Hole.

Everything that falls into the Black Hole winds up in the singularity (in a simple, non-rotating, non-charged Black Hole), but it all gets there at exactly the same time - the time represented by the location of the singularity.

So in a sense, all of the matter that is falling to the singularity is present in the space between the Event Horizon and the singularity at all times except for the one instant of the singularity.

Of course, this does not prevent an observer from posthumously concluding that they fell to the singularity in finite proper time. But I don't think they would find themselves falling through a vacuum - they would be falling with everything else that entered the hole at the same time as they did - matter, radiation, etc.

Further, even if there were a vacuum between the Event Horizon and the singularity, it would not be totally empty. There would still be the zero point energy and there would still be virtual particle pairs being created and destroyed.

I think that in a certain sense the observer brings a horizon with them into the hole. Photons emitted by objects closer to the singularity cannot climb "up" to meet a free-falling observer, so the observer has a hidden region, no? This hidden region should split particle pairs I think, and produce Hawking radiation. Since the surface area of the hidden region shrinks as the observer falls the apparent temperature should go up, and by the time they hit the singularity the observer should be well-fried.