Black Holes Vanish

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Black holes don't exist. Well, they do exist, but they're not black. Or, to be more precise, they still behave like black holes, they just never form the part that makes black holes look black. At least, that's the gist of some controversial calculations by scientists at Case Western Reserve University.

A black hole has two main parts. The first is the "singularity." It contains all the black hole's mass, squeezed into a mere pinpoint.

The singularity's powerful gravity creates the second part of the black hole, the "event horizon." It's the distance from the singularity at which not even light can escape. It's what makes a black hole black. Anything that falls through this horizon is lost to the outside universe.

But the Case Western scientists looked at several problems with the idea of black holes.

One example comes from Albert Einstein's theory of gravity. It says that if you watch a black hole from afar, nothing ever appears to fall in. If you throw a rock toward a black hole, it appears to move slower and slower, while its light is shifted to longer and longer wavelengths. The rock does fall in, but you'll never see it do so.

And if nothing ever appears to fall in, then there can't be an event horizon. And without an event horizon, there's no black hole.

The scientists say that the "black star" influences matter and space around it just as a black hole would. But technically speaking, they say, it's not a black hole.

Script by Damond Benningfield, Copyright 2007

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