Aether 'Density'

Here's a little pure speculation for you. One can ask, what is the relative contribution of each primary electric field to the medium at a given location? One possibility is that the 'weighting factor' is proportional to the electric field strength at a given location. Since the electric field strength falls off as the inverse square of the distance from the source particle, one would expect pretty big variations in the effective state of 'rest' of the medium and the propagation speed of the medium. In other words, stars (and planets) would tend to carry their own state of rest with them. For example, the dominating medium around the earth would more or less move with the earth, and we might expect to see significant variations in the characteristic speed (speed of light) with distance from the earth.

On the other hand, if there was no weighting factor at all, in others words if the contribution of each field element was completely independent of field strength, then one might expect the characteristic speed to be totally constant and the state of rest to be solely determined by the 'average' state of motion of all particles in the universe.

Now, if the weighting factor were dependent on the inverse distance from the source particle (like the electric potential), then one would expect an intermediate result. For example, the characteristic speed would be nearly constant, varying just a tiny bit near massive objects. And friends, this is precisely what we see. Likewise, the local effective state of rest of the medium would almost solely determined by the average state of motion of all particles in the universe.

Ernst Mach dimly perceived that something like this could be the case. In a sense, local physical laws are determined by the large-scale structure of the universe.