From: Matt Mahoney (matmahoney@yahoo.com)
Date: Fri Aug 24 2007 - 15:20:55 MDT
I think that there are explanations for the Eridanus Void that don't require a
superhuman intelligence. (It is in the constellation Eridanus, see
http://www.world-science.net/othernews/070823_void.htm )
We observe an expanding universe and extrapolate backwards to the conclusion
that the universe must have been condensed into a single point at the
beginning of time. Never mind that Einstein's general theory of relativity is
based in part on the assumption that spacetime has no discontinuities.
If you calculate the radius of a black hole that would be formed by all the
mass of the universe, 2Gm/c^2, it is (order of magnitude) the size of the
universe today. So why did it not collapse billions of years ago when it was
much denser?
We observe anomalies in the cosmic background radiation, and postulate
"inflation", a faster than light expansion of space right after the Big Bang.
We observe galaxies not only receding, but accelerating away. We postulate a
mysterious "dark energy", a sort of negative gravity, inconsistent with
general relativity.
The way we keep bending the laws of physics to fit the data reminds me of
early astronomers inventing epicycles to salvage the well established theory
that the sun and planets revolve around the earth.
Consider what you would observe if you were falling toward a massive black
hole. As you approach a massive body, relativity predicts that your clock
will speed up. Since the speed of light is constant in your frame of
reference, nearby objects will appear to accelerate away in all directions.
As you approach the black hole, it will at first fill half the sky. But
because of gravitational lensing, almost any direction you look will be toward
the hole. Any light radiating from objects very near the event horizon will
also be extremely red-shifted (e.g. from gamma rays to microwaves).
Black holes are predicted by general relativity, so they cannot violate
continuity of spacetime. From your point of view, the event horizon is
infinitely far away. You cannot reach it because the closer you get, the
faster your clock runs and the more it appears to recede. The popular view is
that once matter crosses the event horizon, it cannot escape. But this view
also violates general relativity's symmetry of time. If nothing can escape,
then nothing can enter it either.
A black hole model of the universe does not require any new physics. Dark
energy is just gravity. There is no discontinuity, no inflation, no
mysterious expansion of space. But there is one difference in this model.
There should be a small spot in the sky, looking directly away from the black
hole, where you are not looking toward the event horizon. Depending on how
close you are, this spot could be arbitrarily small. You might never find it.
But now I think we might have.
-- Matt Mahoney, matmahoney@yahoo.com
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