Topological interpretation of Dirac equation and geometrisation of   electromagnetic field
  A new concept of geometrization of electromagnetic field is proposed. Instead of the concept of extended field and its point sources, the interacting Maxwellian and Dirac electron--positron fields are considered as a microscopic unified closed connected nonmetrized space--time 4-manifold. Within this approach, the Dirac equation proves to be a group-theoretic relation that accounts for the topological and metric properties of this manifold. The Dirac spinors serve as basis functions of its fundamental group representation, while the tensor components of electromagnetic field prove to be the components of a curvature tensor of the relevant covering space. A basic distinction of the suggested approach from the geometrization of gravitational field in general relativity is that, first, not only the field is geometrized but also are its microscopic sources and, second, the field and its sources are treated not as a metrized Riemannian space--time but as a nonmetrized space-- time manifold. A possibility to geometrize weak interaction is also discussed. 
O. A. Olkhov