About spin electromagnetic wave-particle with ring singularity
  An axisymmetric space-localized solution of nonlinear electrodynamics is considered as massive charged particle with spin and magnetic moment. The appropriate solution for nonlinear electrodynamics with ring singularity is investigated. In view of this problem the system of toroidal waves in linear electrodynamics is considered. The problem with boundary conditions on the singular ring of the toroidal coordinate system is investigated. The boundary conditions are taken taking into account the conformity between the toroidal and cylindrical waves on the ring. In this case the singular ring looks like convolute axis of cylindrical system. The appropriate system of wave modes are obtained in an integral form with the help of source function. 
Alexander A. Chernitskii
math-ph hep-th math.MP quant-ph