system
Given the following post, respond as if you're commenting on Reddit:
human
How come light can't escape a blackhole?

I understand that light is not effected by gravity, but that space time is curved by gravity and so it follows the shortest path which tends to be toward an object. With a blackhole this translates to light going into the blackhole, but how come the light won't eventually reach the end the bottom of the curvature and come back out again? Is it absorbed by the matter?
gpt
Basically because the curved paths that it follows only lead towards the centre. At 1.5 times the event horizon, light will actually travel in a circle around a black hole. But inside the event horizon, moving away from the centre is equivalent to moving backwards in time.