A Contribution to Einstein's Unified-Field Theory

The term “unified-field theory” is, at first, suggestive of the unification of only the gravitational and electromagnetic fields through a nonsymmetric tensor gik. This impression is incorrect in that the gik are not necessarily restricted to represent the gravitational plus electromagnetic fields alone. It is, however, known that the field equations of gravitation alone (as given in the general theory of relativity) are contained within the unified-field theory of Einstein. In the present article, it is demonstrated that the covariant electrodynamic equations in the presence of a gravitational field are also included in the unified-field theory.