Light velocity may be relatively Lorentz-factor variable, and if so:
observers measure the same light velocities & physics changes dramatically while complying with its experimental foundations
A Theory of Light Relativity (TLR): tested yet unchallenged
A novel relativity physics in which observers use abelian (commuting) spacetime-based equations to interpret the experimental foundations of physics. These observers' measurement perspectives of both the cosmos and particle physics are consistent with a unified quantum electrodynamics model that eliminates singularities, complies with Mach's principle, and resolves (with plausible physical paradigms) many of the outstanding conundrums in post-Newtonian physics.