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Old September 27th 06, 03:23 PM posted to alt.astronomy
Greg Neill[_2_]
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Posts: 42
Default The Oldest Light in the Universe

"Hagar" wrote in message
...

"Greg Neill" wrote in message
m...



Your model of the Big Bang is flawed; you're picturing
everything rushing out of an explosion into pre-existing
space. The BB was an explosion (expansion) of space
itself, occurred everywhere (everywhere that existed) at
once, and there was no center.


OK, I'll bite on this one: if there was NO space before the BB, what was
there instead ??


As far as we know, nothing. Our theories do not describe
anything that preceded the BB, nor what, if anything, the
primordial universe might have been embedded. What the
theory does say is that at the instant of the beginning
of the BB, all of spacetime (all three spaceial dimensions
and time) were extremely compact.


The expansion was so fast that light from events that
happened even relatively close to one another could
not reach each other since the space between expanded
at many times the speed of light itself.


That's been termed as "hyper-inflation", since there was nothing to impede
the outward expansion into the existing, infinite VOID of space!!


Again, it was space itself expanding. Contrary to
what may seem common sense, it wasn't expanding into
any pre-existing void.


We're seeing light that left those (then) "nearby" events just
arriving now. So when we look out into space in *any*
direction, we're looking back in time towards the Big Bang.


Once again, you cannot shoot a gun and then run fast enough to where the
bullet finally hits the ground, spin around and take a photograph of the
muzzle flsh.


In the beginning space was compact, but even so all points
were surrounded by an infinite amount of other points.
Think of it as being very, very dense. When space expanded,
every point was surrounded by events that were carried
away from them by the expansion. The BB occurred *everywhere*
around every point that made up the primordial universe.
So it's not necessary to "run and catch up" to see the BB
from any given point -- the BB surrounded every point.


As far as the background emissions, I think that the Universe wants to

be
at
the absolute Zero, but the combined radiation of the billions of

galaxies
is
enough to keep the ambient galactic temperature at about 3.5 or so
degrees
above zero. As they are receding from each other, that is very slowly
dropping towards zero, and by the time the last stars blip out into
oblivion, everything will stop.


Nope. The cosmic background radiation is much more uniform
than the clumpy matter concentrations of galaxies, and
matches the curve of black body radiation very precisely.


COBE determined that the background radiation is indeed NOT uniform, but
rather blotchy. Even though that difference is measured in fractions of a
degree K, nonetheless it matches the "clumpiness" of galaxy cluster
distribution throughout the observable universe.


Maybe you should revisit the figures. What's the magnitude
of the "blotchiness"? I think you'll find that the background
is remarkably uniform, and that the deviations are very, very
tiny in temperature.