Non-Minimal Coupling Efiects of the Ultra-Light Particles on Photons Velocities in the Radiation Dominated Era of the Universe
The efiect of the ultra-light masses of the order of the Hubble constant, implemented in Einstein's fleld equations from non-minimal coupling and supergravities arguments, on photons velocities in the radiation dominated epoch of the Universe within the framework of non-minimal interaction of electromagnetic flelds with gravity is developed and discussed in details. c