From: Loren Haarsma (lhaarsma@calvin.edu)
Date: Mon Aug 19 2002 - 18:07:27 EDT
On Fri, 16 Aug 2002, Iain Strachan wrote:
> Something further might be worth adding here, having read the website
> in more detail.
>
> The fact is that the authors of the website are not at all happy with
> the idea of a geocentric (or galacto-centric) universe, and therefore
> adopt and equally unacceptable (to the mainstream cosmology)
> alternative. Namely that the cosmological red-shift relationship is
> incorrect.
>
> There are some fascinating articles to back this up, concerning the
> observed proper motion of quasars. They maintain that far from being
> extra-galactic objects, they are in fact stars in our own galaxy ,
> and the so-called "red-shift" is down to laser physics. If they were
> at the distance indicated by cosmological red-shift, then their
> proper motions would indicate speeds vastly in excess of the speed of
> light, which is of course impossible.
>
> This is an uncomfortable position to adopt because it undermines the
> whole notion of the expanding cosmos, big bang etc.
>
> My creationist colleague, whom I mentioned in the last posting, has
> reviewed in depth the work of another maverick astronomer Halton Arp,
> who similarly maintains that the cosmological red-shift is incorrect.
> It is of interest to note that the general response of the scientific
> community has been to ostracize Arp, to the extent that he is not
> able to publish anything in peer reviewed literature.
Some additional information relevant to this:
There are several strong, independent lines of evidence that quasars are
extra-galactic and that their red-shifts are cosmological. I'll just
mention one compelling line of evidence: gravitational lenses. (I know a
bit about them because a colleague of mine here at Calvin College studies
them.)
Some quasars are positioned such that a large galaxy or, more typically, a
cluster of galaxies is almost exactly along a line-of-sight between us and
the quasar. We know the distances to these "intervening" galaxy clusters
by measuring the distances to the variable stars and supernovas within
them. We know that the quasars are beyond these galaxy clusters because
the gravitational field of the cluster bends the light (and radio waves)
from the quasars on their way to us. This bending or lensing of the light
(radio waves) can create multiple images of the same quasar. Moreover,
because the light (radio waves) of each image of the quasar takes a
different path to us, there is a "time delay" amongst the images. (The
light from one image reaches us several hours or several years before the
light from the other images.) The exact time delay amongst the images
depends upon the exact geometery of the particular lens. By measuring the
time delays and modeling the mass of the intervening galaxy clusters, we
can get an independent measure of the cosmological distances involved.
These distance measurements from gravitational lenses independently
confirm the cosmological red-shift measurements of distance.
As for the apparent super-luminal motion in some quasars, that's been
figured out, too. If you've got a galaxy core and a jet of material
inside that galaxy both emitting radio waves, and if the jet is moving
away from the core at high velocities in a direction which is mostly (but
not entirely) along the line-of-sight between the core and the observer
(us), the jet will appear to be moving "super-luminally." That is, if you
make the (mistaken) assumption that the jet is moving in a direction
perpendicular to the line-of-sight between the core and the observer, then
the jet would have to be moving super-luminally to shift its apparent
position as much as it does. However, if you assume that the jet is
moving in a direction nearly along the line-of-sight, its velocity really
is sub-luminal. An example of this is in a _Science_ article, "Flashing
superluminal components in the jet of Radio Galaxy 3C120" by Gomez et al.
Loren Haarsma
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