How can black holes spin if the event horizon isn't a surface but just the border between where light can escape and where it can't? A black hole is assumed to be a singularity or the "entrance" of an Einstein Rosen Bridge (while white holes are the "exit" of one) so how can it spin and how can you tell how fast it spins (on its event horizon or whatever)? Isn't it rather the accreted material that is spinning around the black hole?



Browse other questions tagged .