Effective Lagrangian for strongly coupled domain wall fermions

TL;DR

This paper derives an effective Lagrangian for mesons in strongly coupled lattice gauge theories with domain-wall fermions, revealing their doubled and massive nature in this regime, with implications for overlap fermions.

Contribution

It introduces a formalism using supergroups to handle Pauli-Villars fields and derives the meson spectrum in the strong-coupling, large-N_c limit for domain-wall fermions.

Findings

Domain-wall fermions are doubled and massive in the strong-coupling regime.

The formalism applies to overlap fermions as well.

The spectrum of pseudo-Goldstone bosons is explicitly calculated.

Abstract

We derive the effective Lagrangian for mesons in lattice gauge theory with domain-wall fermions in the strong-coupling and large-N_c limits. We use the formalism of supergroups to deal with the Pauli-Villars fields, needed to regulate the contributions of the heavy fermions. We calculate the spectrum of pseudo-Goldstone bosons and show that domain wall fermions are doubled and massive in this regime. Since we take the extent and lattice spacing of the fifth dimension to infinity and zero respectively, our conclusions apply also to overlap fermions.