Just to add a twist to the conversation, if light (in a vacuum) travels at the speed of light, (a fair assumption) and a black holes gravitational pull is greater than the velocity of light (making it "black"), and the general theory of relativity suggests nothing can travel faster than the speed of light, then..... The light trapped by a black hole must in fact be stationary, not moving towards the centre as suggested, to move backwards towards the centre it would have to be dragged back faster than the speed of light. Problem: Balck hole theory is wrong or Einstein was wrong....what gives???