Exact chiral invariance at finite density on the lattice

TL;DR

This paper introduces a lattice action for the overlap Dirac matrix at finite density that exactly preserves chiral invariance, derived from domain wall fermions with chemical potential applied to physical modes.

Contribution

It presents a novel lattice formulation maintaining exact chiral symmetry at finite chemical potential, linking overlap fermions to domain wall fermions with mode-specific chemical potential.

Findings

Exact chiral invariance on the lattice at finite density

Derivation from domain wall fermions with mode-specific chemical potential

Preservation of physical mode contributions

Abstract

We propose a lattice action for the overlap Dirac matrix with nonzero chemical potential which is shown to preserve the chiral invariance on the lattice exactly. We further demonstrate it to arise from the Domain wall by letting the chemical potential count only the physically relevant wall modes.