Abstract
We especulate on the dynamics of charged photons admitting a hypothetical non-neglible photon charge Q_\gamma, albeit our limited understanding of extragalactic magnetic fields and of the expansion of the universe lead to uncertainties on its bound. We found a wavelength for the charged photons proportional to \sqrt{Q_\gamma /N_p}, where N_p is their number density. The light waves frequencies being of the order of the cosmic rays (>10^19 Hz).
Enrique Canessa