Undoubled Chiral Fermions on a Lattice

Abstract

We analyze the dynamics of an $S{U}_L(2)\otimes U_R(1)$ chiral theory on the lattice with a strong multifermion coupling. It is shown that no spontaneous symmetry breaking occurs; the ``spectator'' fermion ${\psi }_R$ is a free mode; doublers are decoupled as massive Dirac fermions consistently with the chiral symmetries. In 1+1 dimension, we show that the right-handed three-fermion state disappears at the threshold and an undoubled left-handed chiral fermion remains in the continuum limit.

Comments: Talk presented at LATTICE96 (chiral gauge), Latex