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Is the event horizon of a black hole physical?

 
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Jan24-13, 04:50 PM   #69
 
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Is the event horizon of a black hole physical?


Well that paper appears to treat them as mathematically equivelent whether they are or not is something I would definetely like to know asa well. If you happen to find the answer in the other post or other sources I would be interested.

I'm starting to make headway now on that paper, its slow going as I'm also looking at Hawkings radiation and a paper on quantum fluctuations of a vacuum. There is several correlations but its too early for me to describe them.
Jan24-13, 05:20 PM   #70
 
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Here is a description [no source] which I liked:

Let me describe a Rindler horizon scenario. Two ships are accelerating together at 1 g for a long time approaching near c. One of them runs out of fuel and stops accelerating. The accelerating ship will see the out of fuel ship fall a little behind, but then become red shifted, clocks on it appear to slow down and asymptotically stop; red shift grows to infinity. The empty ship becomes invisible. The empty ship is never seen to be farther than a short distance away from accelerating ship, as long as it can be seen at all. It is 'trapped' on the Rindler horizon. Of course, for the empty ship, nothing strange has happened. The other ship accelerates away from it, getting ever further away. The empty ship can receive signals from the accelerating one, but any signals it sends can never reach the accelerating ship (because the accelerating ship stays ahead of the light; no contradiction because it had a head start and keeps accelerating.
This has direct implications for other horizons:
http://gregegan.customer.netspace.ne...erHorizon.html

An 'odd' consequence [to me] is that the accelerating ship sees vacuum particles the inertial [out of fuel] ship does not, via the Unruh effect Yet the accelerating ship can't get signals from the inertial ship. The inertial ship receives signals from the accelerating ship but not the extra vacuum signals. This seems a weird information flow!
Jan24-13, 05:34 PM   #71
 
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lol yeah I'm definetely going to have to add that one to my reading material.
and your right it does seem strange on the information side.
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