Black Hole Physics
Most recent answer: 06/13/2011
- Anonymous
Of course, from the point of view of whoever is falling in, after an ordinary finite length of time they cross the horizon. As they do, they see the last of our outside world, looking into the "future" of a narrower and narrower cone of sight. What happens to them afterwards from their point of view? You're right to be asking questions. As for how we can fit their point of view and ours into some unified concept of the world, we leave that headache as an exercise for the reader.
Mike W.
(published on 06/13/2011)
Follow-Up #1: can gravity escape a black hole?
- Don (age 60)
Arkansas
That's a nice question. If somehow a black hole could appear without any gravitational bending of spacetime associated with it, we'd have trouble explaining what could happen. However, that's not what happens, or what can happen. As the black hole gradually forms, the gravitational effects from that mass already extend out throughout space. In other words, gravity doesn't have to escape the black hole and travel elsewhere, it already is elsewhere before the black hole forms. Incidentally, as we mention above, it actually takes the black hole infinitely long to fully form, so we actually never quite get to that stage.
Mike W.
"Our Theory of Gravitation is as good as perfect.... Nothing can act but where it is...; only, WHERE is it?" Thomas Carlyle. 1831
(published on 08/13/2013)