James
Light is a definitive, physically existent effect in photons, which is created as the result of an interaction of certain physically existent photons with a specific physically existent state of any given matter. Precisely how this all works is irrelevant at the generic level. The relevant point being that for every given physically existent state of anything, there are many, specific, identical, physically existent states of the effect (ie light). Once created, these all have an independent physical existence (ie each light from another, and all lights from the matter). These effects (ie lights) travel, sometimes being received by an observer. And this occurrence repeats, with a subsequent existent state of the matter, thereby rendering a sequence of different effects.
So, irrespective of whatever happens to the light as it approaches other matter, that can have no effect on the matter which existed, (and which the light 'represents'-in the context of the sensing system know as sight), that was involved in the interaction which resulted in its creation.
If this did occur, ie light is slowed as it approaches matter, then there would be an effect in the observation of reality (ie the matter).
Whilst the gravity effect of the 'recipent' matter could have an effect on the 'emitting' matter, the question arises as to why this just happens to be an opposite and equal effect to that which the 'recipient' matter has on light? How does it happen that two different causal factors have the opposite but equal effect on different types of entity?
The assertion: ""Since photons hold atoms together, it is postulated that length contraction of bodies of matter results from the length contraction of photons", involves a number of presumptions. Apart from which, light is not photons, it is an effect in photons. Furthermore, the two effects are not directly comparable, because they are not physically existent at the same point in time. There was a point in time when the matter had a given physically existent state. At that point in time, light was also created as a result of an interaction with that state. That light then continues to exist (by some means) as it travels, ie over time. And it is in this duration that it is, possibly, affected (ie slowed) by the other matter it is travelling towards. The physically existent state of the matter, represented by that light, ceased to exist as of the next point in time. Alteration occurred, and it was superseded by another, different, state, which reacts with different photons, creating different light.
The constancy of light is a function of the way it is created, ie an atomic interaction, and the nature of its physical existence. It is always the same reaction, therefore light always originates at the same speed. And, like any other entity, it will continue at that speed unless impeded upon in some way, and its movement is independent of the 'emitting' object, and the 'recipient' object (which may be an observer, or it may be a brick wall, etc). This is what constancy means, ie invariability/independence. To calibrate it, ie assess a value for its rate of movement, then some other entity must be deemed as the reference. By definition, any reference will suffice, as everything is moving, it is just that some are more practical as references than others. Movement being the comparison of spatial position and the rate of alteration thereof. For comparability, other assessments of movement must be made wrt the same reference.
In other words, as with any entity (which all move), of which light is just another, its calibrated speed will be a differential. The fact that it is the physically existent entity which enables sight, is irrelevant, this does not endow light with any form of 'special' feature. There is then, no need to invoke some explanation for 'constant' light speed, because whenever it is measured, it has not got one. So, whether or not the observer is "aware that the gravitational potential energy is varying", he does not measure "the speed of light as the constant C". A solution is being postulated for a problem which does not exist.
"the length of photons shrinks such that the time required for every photon everywhere in the universe to pass a given point is a universal constant". This means that the effect is omnipresent, or there is, effectively, no effect, because irrespective of the nature of the matter being approached, it has the same effect (ie slowing it) on light.
"The length of a photon is set as equal to the radius of the hydrogen atom" This may or may not be so, but it does not follow that "is the value that corresponds with the universal constant time period". Because there is no such thing in existence. What physically corresponds with the concept of time is the rate at which any given change occurs. 'Photons passing a given point' is but just one example of change. As with movement, and any other such attribute, there is no absolute, only differential established by comparison. Timing, being the method whereby the comparison of frequencies of change is compared (ie measured). Assuming that this is how light works anyway, ie it is not, for example, the transference of the effect from photon to photon, rather like a chain reaction.
Finally, as discussed very recently, again, Einstein's original theory had nothing to do with time, observers, etc, etc. This was a flawed explanation as to what was said to be occurring (which might, of itself, be incorrect) which was already in train before the 1905 paper was written, and culminated in the model: spacetime.
Paul
