Symmetrical formulation of electron--photon scattering in relativistic quantum mechanics

In this paper, electron--photon scattering in relativistic quantum mechanics is formulated in a symmetrical form by making use of a modified form of the photon wave equation proposed by the author in a previous article, together with the usual form of the Dirac wave equation. By solving the coupled wave equations two S matrices are deduced, one with the photon wave function and the other with the Dirac wave function. For a given scattering process, either one may be used to give the correct result, if it is obtainable from both. Thus, the symmetry of quantum electrodynamics is explicitly revealed in this formulation