Ralph Hertle wrote:
The question you are making is, however, based upon the same assumption
that the BB theorists make. That is, that the supposed cause of the BB and
the supposed cause of the expansion of the universe are the same.

By and large, BB theorists do not, in fact, make that assumption. They
assume that the BB started the expansion. Most cosmologists do not
concern themselves with what caused the BB. Since time as we know it
was created at the BB, it is not clear what causality would really mean
in this context. There are some theories that place BB in a broader,
multiversal context, but they are not (yet) mainstream cosmology.

Both those theoretical viewpoints have, as their common basis, the same
true and empirically verifiable argument: that the Apparent Red Shift of
the frequencies of light waves from specifically identified atomic elements
have been observed on spectrographs.

Hubble observed that light from what appeared to be more distant sources
also appeared to be more Red Shifted in their frequencies as displayed on
the spectrographs. He was dealing with frequencies, and he applied the
concept of the Doppler Effect to explain the RS effect.

He was not the first to do so. V. M. Slipher had done so before that,
and Fizeau anticipated the effect before him. All this by way of saying
that Hubble had strong grounds for using the Doppler effect as his
explanation for the observed red shift.

Nor was this effect *only* observed for receding galaxies. It was also
observed in the preceding and following limbs of the Sun. The preceding
limb rotates away from us, the following one toward us. This leads to
a Doppler shift in the light radiated by the Sun; we can tell by the
minute shifts in the absorption lines in the solar spectrum. The amount
of the red and blue shifts in the preceding and following limbs,
respectively, are exactly what are predicted for the Doppler shift. It
is not at all a fanciful or solely theoretical effect.

Even today, the majority of extrasolar planets are discovered by an
application of the Doppler shift. These shifts are tiny, thousandths
of a percent, perhaps, but there just the same, and the stellar wobbles
they represent are the effect of their orbiting planets. The variation
of the Doppler shift with respect to time is exactly what you would
expect of a revolving planet (or planets). Could you explain the same
variations by resorting to the hydrogen absorption you mention below?
I suspect it would be quite a contrivance.

In science the principle of application has always been considered to be a
lesser form of explanation and verification. Because something fits or is
similar does not mean that the causes have been explained or proved, or
that the demonstration in logic or actuality is necessarily logically true
and factual.

Of course not, since these things can never be proved logically and
absolutely true. To prove them would require axioms of science--axioms
that we would have to assume true. That is not a weakness of science;
it means that ideas about the world can be revised without having to
rewrite our basic assumptions each and every time.

Hubble also applied the principle of Euclid's that given a straight line,
that in geometry one could extend the straight line in either direction.
Hubble, observing that most celestial objects were to some extent Red
Shifted in their frequencies of emitted light, also hypothesized that all
things could be moving away from one another. He concluded that the
aforementioned straight lines if continued in the direction of the presumed
origin of travel could cut one another at a common point. He further
hypothesized that all things could have traveled from a common point of
origin.

Hubble thought the universe was expanding. He did not espouse the BB
theory with any kind of vigor. I seem to recall he found it unconvincing.
It was others that used his observations to support the BB theory.

There is another theory that better explains the RS, and, that uses almost
the same set of original empirical facts and identifications of properties
and consequences as the Doppler-Euclid-Hubble explanation.

It has nothing at all to do with Euclid, since every indication shows
that space is non-Euclidean, and yet the BB theory survives.

Lord Rayleigh discovered that hydrogen atoms change the frequencies of
light photons that strike the atoms and that continue on. He said that the
collisions were inelastic, and that he measured the lowered frequencies of
the transmitted photons. He really had discovered the Red Shift, only in a
more fundamental way. Rayleigh's explanation did not rely upon the
application on other theories, e.g., Doppler and Euclid, and, rather, he
found direct repeatable empirical results from laboratory experiments.

Recently, the Cassini space vehicle returned powerful evidence that
hydrogen gas, indeed, does lower the energy level of photons traveling in
space.

Hydrogen gas, and the electrons in the plurality of that gas, as I
understand the matter from a scientist acquaintance, can indeed, lower the
energy level of the photons. A quotient of energy remains, and the identity
of that quotient may be explained further to the scientific public in due
time. I gather that scientist have prior identified these relationships,
and that they are well known.

The upshot of all this, leading to the idea that the hydrogen-photon RS
theory is true, is that the RS has been explained by verifiable scientific
experiments under at least three types of experimental conditions, and that
the factual basis is far more scientific and demonstrable than the previous
explanation. Numerous supporting evidence, being accurate identifications
of facts found when trying to examine the universe from the
Doppler-Euclid-Hubble point of view, also supports the hydrogen-photon
theory of the Red Shift.

Science must now compare the two theories. Many pieces to a complex puzzle
appear to fit together by merit of the RS being logically rather than
associatively explained by the theory of the reduction of photon energy
levels.

It is true that under certain circumstances, light may be absorbed by
hydrogen atoms--in particular, by the electrons orbiting the nucleus.
That does not mean that it has anything at all to do with the observed
red shift of galaxies (other than that it enables us to measure that
shift).

What mostly happens is that the light does not lower in frequency. It
either passes through unaffected, or if it is at one of the right
frequencies, it is absorbed *in toto*, leading to the absorption lines
in a spectrum that indicate the presence of hydrogen gas. The sum total
of the light energy is reduced by a small percentage, that is true, but
each photon either retains all of its original energy, or it is absorbed
entirely (perhaps to be re-emitted later as the electron returns to its
original energy level).

If galactic red shift were due to absorption by hydrogen gas, why is it
that intergalactic hydrogen gas doesn't seem to have an effect on the
observed shift? True, it's very tenuous, but there are cubic megaparsecs
of it. It's a lot of hydrogen. Yet galaxies at roughly the same distance
by other metrics do not exhibit variations in red shift depending on
whether there's a lot of hydrogen gas in the way, or very little. There
are variations, yes--but they don't depend very much on how much hydrogen
gas is in the way.

This is a simplified overview, and real scientists have been weighing in
support of the hydrogen-photon theory of the Apparent Red Shift of the
frequencies of light.

By which you presumably mean those scientists who agree with you that
quantum effects somehow explain galactic red shifts. And the rest of
them are just faking it? Probably you think I'm faking it, too.

I'm afraid I don't play that game. I play the game of science, which
means that you don't discount well-established theories because they
haven't been proven (which can't happen, anyway), and you don't favor
a theory simply because it makes more sense to you. Nature doesn't
always make sense--at least, not initially.

Brian Tung
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