Bill Payne wrote:
> On Tue, 05 Jun 2001 16:02:57 -0400 george murphy <email@example.com>
> > Comment: Halton Arp is hardly a good example of someone being
> > simply because of his unorthodox ideas.
> That's definitely not the impression I got from reading his books.
> "Since the people who make these kinds of observations have now been
> excluded from regular observations on the [Palomar 200-inch]
> telescope.....It is clear there is a vested political interest in
> suppressing these kinds of observing projects." (_Quasars, Redshifts
> and Controversies_, 1987, p 162
Have you never heard the old saying "No man is a judge in his own
case"? It's a lot easier to say "I'm being persecuted" than "Maybe I'm
wrong." As I pointed out, the big bang cosmology was not established
orthodoxy at the time Arp started making his claims, and those claims were
given serious attention.. Moreover, there were a lot of astronomers &
astrophysicists then who thought that quasar redshifts were not
cosmological: I used to present such theories as viable alternatives to a
cosmological explanation for quasars when I taught astronomy in the early
70s. Now there is a good deal of evidence that many quasars are indeed at
cosmological distances. Even if some of Arp's anomalous redshifts were real,
we would need to look for explanations within the total context which
includes all the evidence in support of the big bang.
Don't believe everything you read!
> > Question: Is the van Flandern mentioned below the one who thought
> that he
> > had evidence for a time variation of the gravitational "constant" back
> in the
> > 70s? If so, this was hardly an example of "pseudoscience" but OTOH
> would do
> > nothing to support young earth views: Variations in G over 10^4 years
> > have been (again I'm going from memory) on the order of 10^-6, too
> small to
> > have a significant geophysical effect.
> I'm sure that must be the same Tom Van Flandern, who on his website has
> some interesting stuff about the speed of gravity propogating faster than
> light. He says if gravity didn't propogate almost instantly then the
> planetary orbits would be unstable and move away from the sun. His
> website is:
> I don't remember anything about a variation in the gravational constant,
> but he does spout some very interesting ideas. I think his website links
> to some info by/about Arp.
Thanks for the reference. I'll look at it & comment.
According to general relativity, which is in agreement with all relevant
observations to this point, gravitational waves propagate locally with the
speed of light. But since we haven't detected gravitational waves yet (but
only their effect in damping the orbits of the Hulse-Taylor pulsar) we of
course have't been able to measure their speed.
In Note 8 of _The Mathematical Theory of Relativity_ (2d ed.)
Eddington calculated the damping effects due to on a spinning rod due to the
finite propagation of gravitation according to general relativity. This
takes place because, due to the finite time it takes gravitational effects to
get from one end of the rod to the other, there will be a retarding couple
which slows down the rotation. Eddington showed that the loss of energy
calculated in this way agrees with that which is calculated from emission of
gravitational waves. He comments:
"Laplace anticipated that if gravitation were propagated with the
speed of light this disturbing couple would be large enough to be appreciable
in astronomical systems and deduced from its absence that gravitation must
have a much greater speed. We know now that the first order effect which
Laplace anticipated is compensated; but the loss of energy (1) is actually
the residual Laplace effect of the third order of small quantities, as
determined by modern theory."
It'll be interesting to see if Van Flandern has just gone back to
George L. Murphy
"The Science-Theology Interface"
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