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To: First_Salute
Yet by observation, what do you see, looking westbound at the tip of the L.A.S.E.R. beam? Relative to you, that tip of light must be traveling away faster than any image of it getting back to you; hence, it may appear to you as a "black hole," a "spec" of non-light, there's nothing there.

This is incorrect. What you would see is light travelling at the speed of light.

To wit: a "black hole" is light traveling away from your point of view, faster than the speed of light, relative to your position.

A "black hole" is a gravitational object, similar to a massive star or brown dwarf, in which the gravitational effects are so strong that light cannot escape the event horizon of the black hole.

Supposedly black holes can also radiate light -- a prediction first made by Hawking (I think), but I have no idea if this phenomena has ever been observed experimentally.

26 posted on 01/24/2002 9:49:48 AM PST by UberVernunft
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To: UberVernunft
Supposedly black holes can also radiate light

Oops, this is not quite correct. Let me quote a better explanation:

"From thermodynamic arguments Stephen Hawking realized that a black hole should have a nonzero temperature, and ought therefore to emit blackbody radiation. He eventually figured out a quantum- mechanical mechanism for this. Suffice it to say that black holes should very, very slowly lose mass through radiation, a loss which accelerates as the hole gets smaller and eventually evaporates completely in a burst of radiation. This happens in a finite time according to an outside observer."

28 posted on 01/24/2002 9:56:38 AM PST by UberVernunft
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