Timeline for Detection of the Electric Charge of a Black Hole: How can an electromagnetic field escape the event horizon of a Reissner-Nordström black hole?

5 events

when toggle format	what		by	license	comment
Jul 12, 2011 at 17:41	vote	accept	Benjamin Horowitz
Jul 12, 2011 at 14:36	comment	added	Ted Bunn		Well, when we picture electric field lines, we picture them at a moment in time, so the answer to this question depends on a choice of a time coordinate (or at least of a particular foliation of spacetime into constant-time slices). If you use Schwarzschild coordinates for this, then yes, the field lines end on (or just barely outside of) the horizon. There's a good reason for this: in Schwarzschild coordinates, infalling matter appears to get "stuck" at the horizon, not crossing it until $t=\infty$. (I say "appears to" because this is just an artifact of a coordinate singularity.)
Jul 12, 2011 at 9:21	comment	added	Georg		""Even after the material collapses to form a black hole, the field lines are still there, a relic of the material that formed the black hole."" So, the field lines end on the event horizon? Where is the charge? Inside or on the horizon?
Jul 12, 2011 at 0:59	history	edited	Ted Bunn	CC BY-SA 3.0	added 415 characters in body
Jul 12, 2011 at 0:50	history	answered	Ted Bunn	CC BY-SA 3.0