Propagation of matter wave in a medium

Propagation of matter wave in a medium is found to be governed by a damped Klein-Gordon (or telegraph) equation. This equation and Dirac equation are treated as describing a wavepacket propagating at speed of light. Matter fields analogous to electric and magnetic fields that are associated with the electric charge are found to be associated with particle mass. In this formulation the matter magnetic field vanishes. Moreover, the mass of the moving damped spin - 0 particle in a conducting medium is found to be related to the conductivity of the medium. The electromagnetic field of massive photon following Klein-Gordon equation in a conducting medium is created from the spatial and temporal variations of the charge and current densities. The violation of Lorenz gauge condition is found to give rise to longitudinal wave with zero spin.