[jeffreyH (OP)]

An electromagnetic field arises from a charged mass. If the source mass is then moving with velocity v along the x-axis so the field must be moving with it. Since the limit of propagation is c and velocity addition is not Galilean for light then dilation should follow naturally for a moving field. Would anyone disagree?

[chiralSPO]

Electric and magnetic fields can be transformed into each other by change in reference frame.

This video might help:

[jeffreyH (OP)]

I am not talking about a wire. I am talking about the field. It need not be an electromagnetic field. It could be a gravitational field. The motion of the field has no effect on the motion of the boson. The boson does not move at c plus the velocity of the particle generating the field. That the motion of the field has no influence on the motion of a force carrier is a puzzle. If you don't get this then you won't see the implications.

[jeffreyH (OP)]

I have found what I have been looking for here:
https://en.m.wikipedia.org/wiki/Covariant_formulation_of_classical_electromagnetism

[jeffreyH (OP)]

From Special Relativity by H.M.J Woodhouse, beginning of chapter 8, Relativistic Electrodynamics p 133.

"The requirement that Maxwell's equations should be consistent with the principal of relativity implies that the velocity of photons must be independent of the motion of their source and of the observer".

That is independent of all source motions and all observers. This implies a photon velocity that is relative to some fixed background and that all motion is relative to that of the photon. Since the electric and magnetic constants relate to free space we can conclude that the background is a static field of some kind. Then the propagation of photons is with respect to this static field and not the electromagnetic field.