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 Be the first pioneers to continue the Astronomy Discussions at our new Astronomy meeting place...The Space and Astronomy Agora Re: Escaping Pull Of The Black Hole. Forum List | Follow Ups | Post Message | Back to Thread TopicsPosted by Bruce Jensen/">Bruce Jensen on June 25, 1997 16:31:54 UTC

: : Why do I keep hearing that there is no speed faster than light. How is anyone positive about that. If there is such a speed that is faster, isn't it possible to pass through the horizon of the hole, and come back out without being ripped into pieces? Also, I heard that once you pass through the horizon (supposing that a person did somehow), that death would be inescapable because of singularity, and something about how a person couldn't escape their own future. How can a person's future lie within the black hole, and if it is, could it be the key to time-travel, or maybe a fountaion of youth? just curious.

: The reason shutles can break through the atmosphere of the earth is because the earth has a very small escape velocity. Escape velocity does not depend o nthe mass of the object, but the density. A black hole is an extremely dence star, so it has a great escape velocity. The escape velocity is greater than the speed of light, so light can not escape. Since light is the fastest thing known to man, us scientists prodict that nothing can escape.

Now, wait a second guys! The gravity around a black hole behaves EXACTLY the saem way as it does around a star of the saem mass, given the same distance away. It makes no difference how dense the object is. The problem is, we think of ourselves as being very close to a black hole in order to achieve the spectacular results that we have come expect, and then apply this spacetime warped view to normal circumstances, which we cannot do. The reason a black hole has an EVENT HORIZON is because it is dense, or a lot of matter packed into a space small enough so that it is possible to be gravitationally attracted to the objevct at a point where light cannot escape without physically being inside the object (which is, technically, the singularity). Whew!

: An English scientist used the quantum theory to predict that particles can escape from a black hole. He predicted that when two part of a molecule crossed the event horizen they would split apart. One would go into the black hole and never escape, but the other half goes away from the event horizen and escapes.

This happens for some types of particle that divide into virtual pairs, not regular molecules. It doesn't always happen, and the fundamental idea is that over an immense period of time, even a black hole will eventually evaporate.