Re: Gravity and levity

Hans Aberg wrote:

>In article <[EMAIL PROTECTED]>,
>[EMAIL PROTECTED] (Gordon D. Pusch) wrote:
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>Strictly speaking, I think about a universe that might have a series of
>globs, each which its own life and life span, just as with every other
>subcomponent of the currently observable universe. It is a universe that
>would be much older and much larger than that of the current Big Bang
>model predictions. The globs would not be stable, but considerably more
>dynamic and perhaps also have a great deal of cosmic convection: Perhaps
>the dark matter would not expand as uniformly as the visible matter.
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  The model you are envisioning sounds a bit akin to the chaotic inflation
that has been suggested by Linde, but there is plenty that does not make
sense to me here.  Firstly, it is not at all clear to me what you mean by
cosmic convection, since this term is rarely, if ever, used by astronomers.
Secondly, while the density fluctuations were larger in the dark matter
than in baryonic matter in the radiation-dominated universe since the
radiation pressure only affected the baryonic matter, that is by no means
the case today.  Baryonic matter can cool by emitting electromagnetic
radiation, which means that it can condense to form galaxies and stars,
which the dark matter cannot do, therefore the baryonic matter is
more clumpy than the dark matter, and there is also some evidence
that the dark matter halos of galaxies are more extended than the
visible matter in galaxies.

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>If you take a glob of the size and density of our currently observable
>universe, the estimate that Ulf Torkelsson by the formula GM/(c^2 r) says
>that its expansion rate should start to contract as it is by observation.
>This is currently interpreted as the "acceleration of the universe". I
>then neglect the fact that looking further out also looks further back in
>time. But if the universe, for some reason, hangs together in such a
>model, it might make sense.
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>>... when all the evidence that we have
>>strongly indicates that the Universe =ISN'T= stable and =ISN'T= eternal ?!?
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>The funny thing is that there is experimental evidence that contradicts this:
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  Well, the observable fact that the universe is expanding is the basic
evidence supporting Gordon's statement here, and showing that you
start from an erroneous assumption.

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>The Hubble telescope was pointed at a very small region that appeared to
>be pitch black.
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>Then one found there a large number of very tiny galaxies. These galaxies
>should be at the very outer edge of our currently observable universe.
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>The funny thing, though, with these tiny galaxies, is that they look fully
>formed. Thus, when looking that far, the universe does not become older,
>as it should be in a Big Bang model.
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  No, they do not look like the local galaxies, in general they are smaller
and less regular.  Furthermore we know that the density of quasars is
much higher at a redshift of 2, than in the local universe, which should
also tell us that the universe is evolving.  By studying molecules in
distant galaxies we can see that they live in an environment in which
the temperature of the microwave background is higher than today.
All of this and other observations show very clearly that we live in
a dynamic evolving universe.

Ulf Torkelsson