A general theory of non-abelian electrodynamics

The general theory of gauge fields is used to develop a theory of electrody namics in which the fundamental structure is non-Abelian and in which the i nternal gauge field symmetry is O(3), based on the existence of circular po larization and the third Stokes parameter. The theory is used to provide an explanation for the Sagnac effect with platform at rest and in motion. The Sagnac formula is obtained by considering the platform in motion to be a g auge transformation. The topological phases can be described straightforwar dly with non Abelian electrodynamics, which produces a novel magnetic field component for all types of radiation, a component which is proportional to the third Stokes parameter. The theory provides a natural explanation for the inverse Faraday effect without phenomenology.