Dear Colin,
You have written a thought-provoking essay. Here are my comments:
"Black holes and an expanding universe stand out as absurd."
i think having such a strong assertion at the beginning of your paper may turn off some readers from reading the rest, which I think would unfortunate because you present the subject matter sensibly. I think it would have been better to soften the statement a little, for isn't possible that the apparent absurdity of these notions merely reflects our incomplete understanding?
"The objection is founded on the classical notion of causality." Thank you for pointing this out, it implies that this would be considered a very strong objection, since causality is one of the sacred principles of physics. If I wanted to address this objection I would probably try to do more than quote a couple of (albeit well-respected) physicists and philosophers of science and appeal to a quasi-philosophical principle to support my argument. Could you, for example, have given examples of other situations in which are analogical to the one you discuss? Is there any remotely analogous situation in condensed matter physics, for example?
"Scattering would be detectable as smearing of images"
Wouldn't scattering also affect the speed of light? I'm surprised I could not find a discussion of this, for this might potentially suggest a way of falsifying the idea. If you can derive values for the fluctuations in the speed of light, you could compare it to some recent experimental results. See, for instance
http://www.nature.com/nphys/journal/v11/n4/full/nphys3270.html
(Although they were not testing the tired light hypothesis it seems their experiment might be relevant to it)
"Readers who are willing to reconsider their faith in the
basis of inflationary cosmology may suspect they have been tricked, seduced..."
Well, based on what you wrote it seems a commitment to the tired light hypothesis entails more than just abandoning inflationary cosmology, namely a commitment at least to:
1. A particular interpretation of the complementarity principle which I'm not sure is mainstream
2. A particular process for matter creation for which I am uncertain to what degree it is supported by established physics
3. A particular mechanism for circumventing the second law of thermodynamics.
So, I would say that for a mainstream physicist that is quite a lot to swallow. If you really believe this, then finding more evidence and stronger evidence along all these fronts would be helpful to your cause.
"It can be shown that a reformulation of potential energy using special
relativity provides an exponential potential energy function that can be appropriately
normalized to the rest energy of a test object, thus setting a limit to the
energy available from changing elevation in the gravitational field of a massive
object".
I don't remember if we had ever talked about it, but there is a paper I wrote a while back and revised more recently about the relation between gravitational and kinetic Energy you might find interesting:
http://xxx.tau.ac.il/abs/1003.4824
All in all, you offer an intriguing alternative to the way we currently frame our cosmological observations in terms of Dark energy. But to be very frank, I'm afraid that more will be needed to sway people toward this paradigm.
Best wishes,
Armin