The Dirac -- Kerr-Newman electron
  We discuss the relation of the Kerr-Newman spinning particle to the Dirac electron and show that the Dirac equation may naturally be incorporated into Kerr-Schild formalism as a master equation controlling the Kerr-Newman geometry. As a result, the Dirac electron acquires an extended space-time structure of the Kerr-Newman geometry - singular ring of the Compton size and twistorial polarization of the gravitational and electromagnetic fields.   Behavior of this Dirac -- Kerr-Newman system in the weak and slowly changed electromagnetic fields is determined by the wave function of the Dirac equation, and is indistinguishable from the behavior of the Dirac electron. The wave function of the Dirac equation plays in this model the role of an ``order parameter'' which controls dynamics, spin-polarization and twistorial structure of space-time. 
Alexander Burinskii