Overlap fermion with the topology conserving gauge action

TL;DR

This paper compares the distribution of low-lying eigenmodes of the hermitian Wilson-Dirac operator using a topology conserving gauge action versus the standard plaquette action, showing reduced eigenmode density with the former.

Contribution

It demonstrates that a topology conserving gauge action reduces low-lying eigenmodes compared to the standard action, with preliminary results for dynamical overlap fermion simulations.

Findings

Less density of low-lying eigenmodes with topology conserving action

Preliminary success in dynamical overlap fermion simulations

Potential for improved topological stability in lattice QCD

Abstract

We investigate the distribution of low-lying eigenmodes of hermitian Wilson-Dirac operator, $H_W$, with the gauge action whose form is designed to avoid topology change, as well as with the standard plaquette action. On the quenched lattices, the former gauge action exhibits less density of low-lying eigenmodes of $H_W$ compared to the latter at the same lattice spacing. We also show preliminary results for the dynamical simulation with two flavors of overlap fermions.