Sounds off base to me, but I'd welcome an informed critique.
If you look at his references, you will see the experiments cited are either unpublished (performed by others) or very old (an 1887 Michelson Morley citation if you can believe it). More recent experiments which disagree with his conclusion are completely ignored.
And that is the good part of the paper, as much of the rest is devoted to slamming the physics establishment for wasting the past 100 years.
Cahill also mentions Dayton Miller. Compare this to the Usenet FAQ on the subject:
The Michelson-Morley experiment was repeated with greater accuracy in the years that followed. In 1925 Dayton Miller announced that he had detected a change in velocity of the speed of light and was even awarded prizes for the discovery, but a 1950s appraisal of his work indicated that the most likely origin of his results lay with diurnal and seasonal variations in the temperature of his equipment.
Modern instruments could easily detect any ether drift if it existed. The Earth moves around the sun at a speed of about 30 km/s, so if velocities added vectorially as Newtonian mechanics requires, the last 5 digits in the value of the speed of light now used in the SI definition of the metre would be meaningless. Today, high energy physicists at CERN in Geneva and Fermilab in Chicago routinely accelerate particles to within a whisper of the speed of light. Any dependence of the speed of light on reference frames would have shown up long ago, unless it is very slight indeed.
Cahill claims that the Michelson-Morley data (by his analysis) indicates a non-zero velocity with respect to a preferred reference frame. According to Tom Roberts (in sci.physics.relativity) Cahill did not properly take into account the experimental uncertainties in the M-M data, which can be extracted from the data themselves. Taking the actual uncertainties into account, Cahill's analysis actually is statistically consistent with a velocity of anywhere between zero and several thousand km/sec in any direction.
I'm very interested...
Reg Cahill is a senior member of the Faculty of Science and Engineering at an Australian university (Flinders), is the chairman of the Courses and Curricula committee for the School of Chemistry, Physics, and Earth Sciences in that faculty, but seems to be operating in the realm of fringe science...
Is this good or bad?
Check out the Process Physics page. Remember, this is not a run-of-the-mill crackpot site, this is a serious academic web site at an accredited University.
He is a pottery magician.
This work looks professional and Reginald T. Cahill has referenced some interesting work on Dalton Miller and Roland De Witte (recently deceased), which I fully agree with - namely a sidereal variation in the speed of light.
However, the rest of his work is quite advanced and I can't say whether it's good or bad, without spending more time on it.
...and a search through the archives reveals all.
It's certainly an easy label to apply, but don't you think he's not your run-of-the-mill crackpot? Do you think you might be applying that label a little hastily in this case?
How does he measure up on the crackpot index?
What makes you agree with those but not these:
1. "Tests of Relativity Using a Cryogenic Optical Resonator", C. Braxmaier et al., PRL v.88, p.010401 (2002).
2. "Tests of Lorentz Invariance using a Microwave Resonator", P. Wolf et al., PRL v.90, p.060403 (2003).
3. "New Limit on Signals of Lorentz Violation in Electrodynamics", J.A. Lipa et al., v.90, p.060403 (2003).
4. Muller et al., PRL v.91, p.020401 (2003).
...And it is run by Cahill himself.
Face it, Cahill is trying to tell us that one of the most fundamental concepts of relativity is wrong without himself performing a single experiment to support the charge; and he ignores or rejects all modern published experiments (i.e. in the last 50+ years) which contradict him.
There is no peer acceptance of this work and I don't expect any in the near future for obvious reasons.
It is possible to for Lorentz Symmetry to be upheld 100%, even when the one-way speed of light is only constant relative to a preferred reference fame.
The above experiments seem to imply that Lorentz Violation is a test of the constancy of the speed of light, which it is not. However, there link is strong to the two-way speed of light measurements, but not for the one-way.
Yet, when the SAME type of experiments (Dalton Miller and Roland De Witte) showed hints of such violation, how come you didn't question why it would show up IF what you said is true? I didn't ask why you buy or don't buy the experiments I listed. I asked why you believe in one set, but NOT the other, especially when the latter are testing the SAME thing, with BETTER and more accurate measurements? If you wish to throw out the latter as being "two-way speed of light measurements" and not show any lorentz invariant, then you should also not buy into the experiments that you prefer to believe in.
I remember seeing a discussion on your idea somewhere (may have even been here on PF, a year or more ago) where you described a relatively simple experiment that would (in your view) settle this matter (for you) in a straight-forward way.
IIRC, it wouldn't involve a lot of expensive equipment; with accurate clocks and good lasers being now available at quite reasonable prices, less than a mortgage on an average family home (and maybe not much more than the cost of new Toyota sedan).
It sounded like an interesting experiment, in its own right, so perhaps with the right kind of marketing, and wrapping it up in a nice package, you might be able to find a way to get it done?
Seems to me that spending lots of time discussing how many teeth a horse has is inferior to going out and actually counting them!
And what do people make of these periodic pendulum effects?
The experiment didn't appear to reveal the anomalous effect of the eclipse on the Pendulum as reported in other eclipse events - but as they pointed out - it may be because of the geometric relationship involved in this particular eclipse. What does the principle of mutual interaction say about the periodic effects?
Are you referring to the principle of mutual interation of self creation cosmology?
The experiment needs to be replicated under stricter conditions. In particular it needs to be in a high vacuum isolated from any other field effects and vibrations. It is an interesting concept as it is claiming a higher order Foucault's pendulum effect.
As far as the PMI is concerned the interesting question is to see whether any confirmed results are correlated with the Earth's motion relative to the surface of last scattering of the CMB. They mention a possible correlation with the direction of the centre of the galaxy.
May I ask WHERE exactly do you propose to find such conditions?
Zz - In a carefully constructed laboratory experiment?
How do you propose to achieve isolation from "other field effects" such as gravity, and how high of a vacuum would suffice?
Separate names with a comma.