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An object swallowed billions of years ago thus will retain some incredibly tiny solid angle over which a sufficiently vertical photon will eventually reemerge into the outside world... For a galactic center black hole, how exactly does "pump" mass-energy from the singularity back out to the event horizon... ? ... the apparent horizon at which the ...


We never observe the event horizon begin to form. The entire event horizon is a region of space time outside our past light cone. I don't see how a firewall could form. For a firewall to form, radiation at the event horizon would have to cause the firewall at another part of the event horizon in its own past light cone. Even if we do observe the black hole ...


If you look at the time scale for evaporation (which basically asks you to wait for the black hole temperature to be higher than the cosmic background radiation), you will find that binary black holes will have merged (due to emission of gravitational waves) a long, long time before there is any evaporation happening.


First, the Unruh and Hawking radiation aren't quite "the same thing". They have a similar origin and the Unruh radiation may be considered a flat space (large black hole) limit of the Hawking radiation. Now, the near-horizon metric of an extremal black hole is $AdS_2\times S^2$ while for a non-extremal one, the $AdS_2$ is replaced by the Rindler space. ...

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