Question

For a charged black hole, does the charge appear to lie on the event horizon?

Answer 1

In considering a charged (Reissner–Nordström) black hole, I was trying to figure out if the charge acts as though it is at the singularity or rather behaves as though it is a surface charge density on the event horizon.

From a distance, the two cases would mostly appear the same, yet in close proximity, or for the Kerr situation one would definitely see the difference.

I ask, because I was thinking about Hawking radiation, and if you're near a charged black hole, my understanding is the radiation (not measurable for known black holes, too weak) would necessarily be charged in this case.

If you're near such an object giving off charged particles from the even horizon, would it not have to appear as though the charge lies on the event horizon? Otherwise one has a discontinuity in the behavior of the charge as calculated by someone measuring the electric field from outside.

Answer 2

I assume that the answer is 'hairy numerical model running on a supercomputer'. In other words I assume there's no easy way to do this. I believe that numerical models which work for this sort of thing are fairly recent -- I have '2005' in my head but I'm not sure if that's right. The place to look would probably be LIGO papers, as they are the canonical people who need to do this. – tfb Mar 7 '17 at 15:36