Influence of center vortices on the overlap quark propagator in dynamical QCD

TL;DR

This study investigates how removing center vortices affects the quark propagator in dynamical QCD, revealing their crucial role in dynamical mass generation and nonperturbative phenomena.

Contribution

It extends previous work by analyzing the impact of vortex removal on the overlap quark propagator across multiple quark masses in dynamical QCD.

Findings

Vortex removal suppresses dynamical mass generation.

Vortex-only fields reproduce dynamical mass with smoothing.

Results support the link between center vortices and nonperturbative QCD phenomena.

Abstract

There is strong evidence supporting center vortices as underpinning confinement and dynamical chiral symmetry breaking -- the two key features of nonperturbative QCD. In our recent letter [ arXiv:2305.18690 ] we find that dynamical mass generation vanishes upon vortex removal in full QCD with a near-physical quark mass. In this work we extend those results and consider the influence of center vortex removal on the overlap Landau-gauge quark propagator at multiple valence quark masses on the same dynamical QCD ensemble, keeping fixed the near-physical sea quark mass. After carefully applying a smoothing process we also find that dynamical mass generation is reproduced on the corresponding vortex-only fields. This vortex-only dynamical mass shows qualitative agreement with the untouched Monte Carlo gauge field results. The results reported herein lend further credence to the important relationship between dynamical fermions and center vortices and the mediation of nonperturbative phenomena in QCD.