Steve Andresen,
Hi, It has gotten late. I will just explain why I say that there is no place in the Universe where the speed of light is really 'C'. Another way of saying this is there is no place in the Universe where length is not contracted to less than it could be. Object activity, the very thing that we substitute to serve in place of actually being able to measure time, is never quite as fast as it could be. The reason for these two effects to miss their ultimate mark is that that ultimate mark is unreacheable. It is unreachable because of the infinite extent of mass. The speed of light is regulated throughout the Universe. It varies, but it is controlled. It is the most important property in this orderly Universe. That orderliness is constant proof that fundamental unity exists. Fundamental unity is always the product of a single cause for all effects. Since physics is a mechanical interpretation of the operation of the Universe, I limit what I say to this: The variation of the speed of light is the cause for all mechanical effects. Measuring the ultimate speed of light, true 'C', would be like witnessing the end of the universe. What I mean is that there is never a time during the life of the Universe that the speed of light is not varying.
Mass is the inverse representation of the variation of the speed of light for a single particle. Particles gather together and become complex assemblies of particles. Their masses combine together. As their sum of masses increase in magnitude, the speed of light for them locally is decreasing in magnitude. This is how I find that mass varies and, inversely the speed of light varies for a neutral atom: I don't think that mass begins as a singularity, but, I will let that be the case just for the sake of simplifying this description. If mass begins from a singularity, then it begins with a magnitude of infinity. Again, I don't think this is the case, but it simplifies the curve that the magnitude of mass follows as a function of distance from its center of origin. To be exact, it is mass that is the particle, meaning that a particle consists only of its ability to control the speed of light. Mass represents the magnitude of that speed inversely. So the particle is not made of mass, but, instead is a curve representing the speed of light beginning from its singularity with a speed of zero, and increasing its speed with distance from its singularity.
The shape of the curve that the speed of light follows has a short length where it increases very rapidly. That length is approximately the radius of the hydrogen atom. When that length is reached the speed of light slows very rapidly giving the curve a knee where instead of rising rapidly it bends over until its increase in speed is very small with respect to distance from its singularity. The speed of light does continue to increase, but does so very slowly with distance. When two particles combine their masses, and therefore their control of the speed of light; their masses add together meaning that the two particles cause the increase in the speed of light with respect to distance to slow down. The larger mass becomes, the slower the speed of light increases. For an isolated particle, or an isolated combination of particles, the speed of light does not decrease, but the increase in the speed of light with distance approaches zero. That value of zero would only occur at a distance of infinity. The speed of light would approximately reach its maximum possible value of 'C' only if the Universe expanded to a size that could be mathematically treated as approaching infinity.
The property of mass for protons, electrons, neutrons, or whatever is more complicated than this message indicates. So there is more to be said, but for a neutral atom of group of neutral atoms, this description is adequate as an introduction. My intent was to indicate in physically meaningful way why I said that the speed of light is never actually 'C' anywhere in the Universe. The speed 'C' is the ultimate maximum speed of light.
James Putnam