Still reading your (& Nixey) paper, sporadically. Some thoughts:
Einstein's 1952 view that 'space' is actually "infinitely many spaces in relative motion" is very hard to interpret, but certainly seems to imply that 'locality' is paramount.
That "the nature of light is still subject to contention 100 years after Special Relativity" seems corroborated by the papers in this FQXi contest.
I don't believe that 'empty space' exists, as I believe gravity to be a continuous field filling space everywhere. Frank Wilczek seems to say the same about 'quantum fields' everywhere in space, but I reject 'quantum fields'.
If gravity is the primordial or underlying field, then it may provide the 'medium' in which E and M trade energy as the photon travels, and the C-field circulation, as explained in my essay, helps conserve the photon's inertial momentum.
FWIW, your paper inspired me to re-buy Jenkins and White's "Fundamentals of Physical Optics", the only physics text I've ever sold in my life. Also, FYI, I took 'Introduction to Fourier Optics' under Joseph Goodman, the first time he taught the course out of his book.
You state that "Max Planck's proposal of a compressible aether, more dense at the surface countered Lorentz's first objection...[but not] that the speed of light would be affected by density." It is along these lines that I think my equation 7 may have relevance, when the right hand side is viewed as variation of density.
I have not yet worked out the case of photons traversing a region of space, (dV =dx**3), subject to
d(t)/dV = d(m)/dx --- (in units of Planck action, h) .
The 'time dilation' dt, here would seem to imply that a distributed light wave/photon would 'bend' as a function of the variation in mass density, dm/dx, (where, in the most general case, dm is the change in gravitational energy with x.)
The above is for an extended wave front traversing a variable density region at right angles to the variation in density.
If the direction of the photons is parallel to the direction of maximum variation, then we have a Pound-Rebka type of dilation. This may be consistent with your statement on page 8 (Nixey) that "we now know that light speed is indeed reduced by increasing density in the atmosphere."
That's as far as I've gotten on your Nixey paper, but I find it very well written, extremely interesting, and not too difficult to follow, although I have not checked any of the results.
Thanks for putting me on to that paper. I am very interested in applying equation 7, which is derived in a straightforward manner from my generalized Heisenberg principle, which in turn fell right out of my Master equation, which is essentially a fundamental statement of logic.
Ain't FQXI fun!
Edwin Eugene Klingman