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- Why is a black hole black? 4 answers
There's something which I don't quite get about black holes and event horizons (feel free to tell me if I got something completely backwards at any step along the way):
Say we have a singularity and we launch a particle from the singularity's Schwarzchild radius R at the speed of light directed outwards from the black hole - wouldn't that particle be able to escape beyond R, slowly decelerating in a parabolic path to a halt somewhere outside it (at a radius of, say, R1)?
If so - wouldn't an observer A between R and R1 be able to see that particle as it decelerates? And if so, we couldn't define the event horizon to be at R, because light from R can affect A who's outside it. We couldn't define the event horizon to be at R1 either, because light from the observer could escape R1 entirely.
So where would we define the event horizon in the case presented above? How can there be an event horizon if light can be launched slightly below it and take an parabolic path outside it, even if only for a moment?