%0 Journal Article
%T Integrating out the Dirac sea: Effective field theory approach to exactly solvable four-fermion models
%A Karbstein
%A Felix
%A Thies
%A Michael
%J High Energy Physics - Phenomenology
%D 2007
%I 
%R 10.1103/PhysRevD.77.025008
%X We use 1+1 dimensional large N Gross-Neveu models as a laboratory to derive microscopically effective Lagrangians for positive energy fermions only. When applied to baryons, the Euler-Lagrange equation for these effective theories assumes the form of a non-linear Dirac equation. Its solution reproduces the full semi-classical results including the Dirac sea to any desired accuracy. Dynamical effects from the Dirac sea are encoded in higher order derivative terms and multi-fermion interactions with perturbatively calculable, finite coefficients. Characteristic differences between models with discrete and continuous chiral symmetry are observed and clarified.
%U http://arxiv.org/abs/0708.3176