English

Domain wall fermions

High Energy Physics - Lattice 2026-05-19 v4

Abstract

We introduce the formulation of domain wall fermions in the context of lattice QCD. We prove the recovery of exact chiral symmetry in the limit of an infinite fifth direction, and derive the effective four-dimensional operator satisfying the Ginsparg-Wilson relation obtained in this limit. We discuss the residual breaking of chiral symmetry for finite extent of the fifth direction, and how it is affected by spectral features of the Wilson kernel. We also discuss various improvements of domain wall fermions including notably M\"obius fermions. These notes are a chapter contributed to the on-line book ``Lattice QCD at 50 years'' (LQCD@50).

Keywords

Cite

@article{arxiv.2603.27608,
  title  = {Domain wall fermions},
  author = {Thomas Blum and Yigal Shamir},
  journal= {arXiv preprint arXiv:2603.27608},
  year   = {2026}
}

Comments

81 pages, 7 figures

R2 v1 2026-07-01T11:42:46.959Z