Juergens' Electric Sun model?

You are probably correct in your assessment of my comprehension of the
scales in question. I must say that I've posed that same argument to a
physicist or two who could never answer me. I think your explanation is the
most clear and concise I've ever gotten on the subject. It also makes
sense. I would like to follow up, if I may, to ask you to comment on the
other part (within the galaxy). You state that we do indeed see a mix of
red and blue shift within the galaxy. Is it differential in that at an
object's greatest acceleration away from us (relatively speaking) is the red
shift greater than when it is at its maximum distance? At that point,
theoretically speaking, there should be no shift whatsoever, correct?

Taking the point a bit further, am I correct in assuming that galactic
collisions are gravitationally caused as opposed to two galaxies happening
to cross paths in the way meteors and comments sometimes intersect Earth? I
realize the Sun's gravity is involved there as well. My analogies aren't
always perfect, but are chosen to more clearly communicate what I'm trying
to say.

DBJ

Em Sb 28 Fev 2004 13:11, Donald Brewer, Jr. escreveu:
> Applying this analogy to the galaxy, some stars within the galaxy should
be
> coming towards us and others should be traveling away from us thereby
> representing a mix of blue and red shifts. Perhaps I am mistaken (please
> correct me if I am), but to my knowledge, this is not the case. The only
> rational explanation that I feel might explain this would be if the
> universe is expanding at such a rate that the expansion within the galaxy
> is so great the distance two objects within the galaxy are moving apart
> from each other is greater than the distance that is being closed by an
> object passing us by.

I think that you are misunderstanding the scales where the cosmological
redshift occurs. Inside our galaxy, and even inside our group of galaxies,
gravity reigns, and thus we indeed *see* a mix of red and blue shifts. For
instance, the Andromeda Galaxy is blue shifted, for its is comming to
collide
with the Milkway.

Now, over cosmological distances (tens of megaparsecs) the expansion of the
Universe wins the gravity, and then the groups of galaxies are getting far
from each other - that is, almost all of them are redshifted related to the
others.