Tam Hunt said:
I'm not equipped to judge the merits of his analysis in detail, so I'd be grateful for your feedback on his results and interpretation.
Hi Tam, I had never heard of Cahill before, but having read his analysis of the MM experiment I can safely say that he is a crank. However, since being a crank does not automatically imply that he is wrong I will address the substance of his paper on a few points.
1) "An ongoing confusion in physics is that absolute motion is incompatible with Lorentz symmetry". This is incorrect, it is well known that LET has both Lorentz symmetry and absolute motion.
2) "the evidence is that absolute motion is the cause of these relativistic effects, a proposal that goes back to Lorentz in the 19th century. ... Einstein’s postulates regarding the invariant speed of light have always been in disagreement with experiment". Here he makes the same mistake that you and I have discussed at length. You cannot even in principle have experimental evidence which verifies Lorentz and falsifies Einstein.
3) The speed of light through a moving medium (V) with a refractive index of n is given by V = c/n + v (1-1/n²). Even ignoring the Frensel drag coefficient it is V = c/n + v, not simply V = c/n.
4) There are several post-MM experiments that were performed using some other medium besides vacuum, including one by Michelson and Morely. All verify the Fizeau experiment, which can be derived using SR velocity addition.
5) The MM 8 km/s result is, in fact, a statistically null result as is the 10 km/s result of Miller. In their times it was common to not perform a statistical analysis on the experimental errors, but Cahill has no such excuse. When an error analysis is done it can be seen that their results are not significantly different from 0 km/s.
Anyway, Cahill's paper does not stand scrutiny. He does not understand LET and its relationship to SR, the derivation of his mathematical framework is incorrect, he ignores experiments that directly contradict his claims, and he does not have any statistically significant experiment supporting his claims. I would recommend that you read http://math.ucr.edu/home/baez/physics/Relativity/SR/experiments.html" . Of course, all of the experimental support listed there also supports LET, as we have discussed.