Whither redshift? And other musings on the nature of photons.

I have never seen any attempt to explain any physical process by which the expansion of space would cause redshift, or by what means the expansion of space would accelerate or decelerate.  Now, this doesn't mean there is no explanation, just that I, in looking, have never found one.  I don't claim to be a professional (or even well trained) physicist, so there are real limits to my knowledge.

That being said, this lack raises my hackles.  Results must have causes.

After a great deal of thought, I have come up with this.  If space is expanding, and if that expansion somehow causes photons to lose energy (redshift), then lower energy, longer wavelength photons would necessarily lose proportionately more energy than higher frequency, shorter wavelength photons.  This would appear as acceleration.

This thought experiment should be testable, as different frequencies of light from the same source would show ever so slightly different redshifts.  If this is true, then the expansion of space need not be accelerating.  If this s not true, the how is space expansion affecting photons, if it doesn't stretch longer waves more?  Unless the wavelength of a photon is an artifact of a point-like spin frequency, and not an inherent property.

And where does the lost energy go?  Is energy simply not conserved?  That is what the theory implies.  Remember, if energy is lost, it must be lost as some particular time and place.  For that to happen, it must go somewhere, or be transferred into some other form.  Unless all energy is slowly being reduced over the entire history of the universe, of course.  Then it would be time causing redshift, not distance.  A distinction without a difference, really, since it's all spacetime, but intellectually more satisfying.

Come to think of it, what is the wavelength of a photon newly emitted by an electron?  If the frequency is in the AM radio band, the wavelength is measured in many meters.  How would it work for a photon with a wavelength of, say, ten meters, to be emitted and then absorbed by two atoms a mere centimeter apart?  Where is the energy held in a photon?  The leading edge of a wave, with the wavelength being an artifact of its passing?  It cannot be a pointlike center of a full wave, or even the entire wave.  No, it has to be the leading edge, for something has to cause the leading edge, and nothing can travel faster than the photon itself.  It makes the most sense if the photon has a spin, and the wavelength is an artifact of the frequency of spin interacting with the EM field, trailing along behind.  But that makes the double slit experiment results rely on the passage of previous photons, negating all the "woo-hoo" effects.  That would also mean the wave function wouldn't have to exceed to speed of light (in some directions but not others) to achieve the necessary addition and subtraction effects.  (Yes, the standard explanation of the double slit diffraction grating requires a variable speed of light - for the same photon.  Measure the paths.)

I knew I liked where that thought was heading.  Has anybody ever done a double slit experiment while also shining a strong light of the same wavelength longitudinally between the grating and the detector?  I honestly don't know.  I do know that I have seen no evidence of the experiment ever actually being performed with single photons, mostly because I don't think anybody has ever found a way to create a reliable means of emitting single photons of the same wavelength from a source.  No, applying filters doesn't count, especially when the wavelength is longer than the average separation.