On Wed, Aug 01, 2001 at 03:07:14AM +1000, Miriam English wrote:
> Nobody has
> actually even seen a black hole in action yet as far as I know. We are
> pretty damn sure they exist and are at the heart of most(?) galaxies, but I
> don't think we yet have any direct evidence that they even exist, let alone
> certainty about what goes on inside them.
Actually, the observational evidence starts to look good. Check out
http://www.sciencedaily.com/releases\2001\01\010111194759.htm
http://www.sciencedaily.com/releases\1997\11\971107071006.htm
http://www.sciencedaily.com/releases\2000\05\000516072438.htm
http://www.sciencedaily.com/releases\2000\01\000113233828.htm
http://www.sciencedaily.com/releases\2001\07\010720093143.htm
http://www.sciencedaily.com/releases\1999\12\991215103043.htm
There are several ways of detecting them (gravitational lensing, X-rays and
accretion disks), making it hard to explain away the results.
Also, it doesn't matter the least what happens inside black holes because
they are objects where information from the inside cannot escape. Hence, if
a black hole swallows 1 kilogram of matter, it will now gravitate with a
mass 1 kilogram larger. So stuffing down matter and energy into them will
result in a larger hole with a stronger gravitational field, making them
useless for saving the steady state model.
> But, I wasn't actually saying that matter *is* crushed out of existence
> inside black holes, it was an *if*. I was simply posing speculative
> possibilities in response to your earlier hasty post.
OK. You can actually use a black hole for cooling if you put it into a
sealed chamber and don't let any matter fall in (then it will absorb the
blackbody radiation from the walls), but it isn't a likely state in the
universe.
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