7
votes
Might the tiny Hawking radiation from our cosmic event horizon (CEH) be additive, since my CEH is not your CEH?
No, it is not additive. The reason is the origin of these sorts of effects. For simplicity, I'll treat our Universe as being exactly de Sitter.
Firstly, I should notice that the thermal radiation on ...
3
votes
Does the event horizon always stay below you in the frame falling freely with you in a black hole?
There is no moving event horizon for a falling observer. It is still the case that this observer cannot receive information about events inside THE event horizon until they have also passed inside it.
...
2
votes
Accepted
Calculating coordinate increase of light ray escaping black hole
What you are doing in the "dividing by $dv$" step is, rigorously, a part of imposing that the tangent $k^\mu$ to the photon's worldline is a null vector. If you want to do it in a "...
2
votes
Does the event horizon always stay below you in the frame falling freely with you in a black hole?
The usual presentation of black holes being black because light can't escape is misleading. When you look towards a black hole, what you see is determined by your past light cone, which the black hole'...
1
vote
Does the event horizon always stay below you in the frame falling freely with you in a black hole?
So it seems there is a radial distance from behind which light can't reach you.
This is incorrect. It is easiest to see in Kruskal–Szekeres coordinates:
What makes these coordinates so useful is ...
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