Singularity structure of a model quark propagator

Abstract

A model Schwinger-Dyson equation for the fermion self-energy is solved for both spacelike and timelike momenta. The singularity structure of the quark propagator obtained as a solution of this equation is studied. It is found to be an entire function (except for an essential singularity at p2 = -∞; timelike in our metric): a property that may be indicative of confinement. The absence of singularities is a non-trivial feature that arises only as a result of the cancellation of zeros in the numerator and denominator of the propagator. Show more