A Derivation of Dirac's Equation From a Model of an Elastic Medium
  Starting from a model of an elastic medium, we derive equations of motion that are identical in form to Dirac's equation for a spin 1/2 particle with mass, coupled to electromagnetic and gravitational interactions. The mass and electromagnetic terms are not added by hand but emerge naturally from the formalism. A two dimensional version of this equation is derived by starting with a model in three dimensions and deriving equations for the dynamics of the lowest Fourier modes assuming one dimension to be periodic. Generalizations to higher dimensions are discussed. 
John M. Baker