We survey the correct definition of a generalized Dirac operator on a Space-Time and the classicla result about propagation of singularities. This says that light travels along light-like geodesics. Finally we show this is also true for generalized Dirac operators.
Cite this article
Paolo Antonini, Generalized Dirac Operators on Lorentzian Manifolds and Propagation of Singularities. Rend. Sem. Mat. Univ. Padova 126 (2011), pp. 237–244