Kinks and bound states in the Gross-Neveu model.

Abstract

We investigate static space-dependent \ensuremath{\sigma}(x)=〈\ensuremath{\psi}\ifmmode\bar\else\textasciimacron\fi{}\ensuremath{\psi}〉 saddle point configurations in the two-dimensional Gross-Neveu model in the large N limit. We solve the saddle point condition for \ensuremath{\sigma}(x) explicitly by employing supersymmetric quantum mechanics and using simple properties of the diagonal resolvent of one-dimensional Schr\"odinger operators rather than inverse scattering techniques. The resulting solutions in the sector of unbroken supersymmetry are the Callan-Coleman-Gross-Zee kink configurations. We thus provide a direct and clean construction of these kinks. In the sector of broken supersymmetry we derive the DHN saddle point configurations. Our method of finding such nontrivial static configurations may be applied also in other two-dimensional field theories.