Quote (bentherdonethat @ Oct 20 2011 10:20pm)

Saying that the escape velocity is greater than the speed of light just means that nothing can ever escape it. It's not perfect, but it's not bad for a one-line definition.

The Schwarzchild radius is the "point of no return", meaning if light (or anything else, of course) passes within that radius it can never escape. You're correct in thinking that escape velocity is no longer relevant inside that radius since space itself contorts such that escape is impossible.

Of course, if one could find a way to travel to a fourth spatial dimension that was NOT curved as much as the three spatial dimensions that we experience regularly, then you could potentially escape. However, that's hypothetical at best and extremely unlikely.

Quote (bentherdonethat @ Oct 21 2011 05:03pm)

Novocane, I answered that already.

Quote (novocane @ Oct 21 2011 05:10pm)

that definition implies that escape velocity is part of the reason light can't escape

also, its more than just a one-line definition; they use it to calculate the radius of black holes

so why would they put something in the definition and then use it to make calculations even though that something is completely irrelavent

Quote (novocane @ Oct 21 2011 06:10pm)

that definition implies that escape velocity is part of the reason light can't escape

also, its more than just a one-line definition; they use it to calculate the radius of black holes

so why would they put something in the definition and then use it to make calculations even though that something is completely irrelavent

Quote (bentherdonethat @ Oct 21 2011 05:26pm)

If spacetime didn't warp at all, then the escape velocity description would be completely valid. That's why it's used to calculate that radius. Something can be mathematically useful and conceptually irrelevant at the same time. It's just that escape velocity is a simpler calculation than performing the one to find the point where the spacetime curvature is such that everything points back towards the black hole.

Quote (novocane @ Oct 21 2011 05:29pm)

But even if spacetime didn't warp, the escape velocity of light still wouldnt matter.  If spacetime didn;t warp light would be able to escape would it not?

Quote (L4d @ Oct 21 2011 05:34pm)

Light cannot change its course like a ship or whatever, so once it is pulled close enough, it would be unable to escape, no?

Quote (novocane @ Oct 21 2011 05:37pm)

no because it doesn't get pulled close because light is massless

Quote (L4d @ Oct 21 2011 05:39pm)

Light is effected by gravity.
The only way for light to escape without the event horizon is if it had enough momentum?

Quote (novocane @ Oct 21 2011 05:53pm)

lights energy is affected by gravity but its position is only indirectly affected by gravity. gravity can't "suck light in" like it could a space ship.  any change in the path of light by gravity is done by the bending of the spacetime the light is traveling through.

and in the hypothetical "if black holes didnt warp spacetime", then light would be able to escape them