Testing a Topology Conserving Gauge Action in QCD

TL;DR

This paper investigates a gauge action in lattice QCD that maintains a fixed topological sector, facilitating more efficient simulations in the epsilon-regime and potentially benefiting dynamical quark simulations.

Contribution

It introduces a topology conserving gauge action and demonstrates its effectiveness in confining the topological charge during Monte Carlo simulations.

Findings

Topological sectors are effectively preserved over long simulation times.

The proposed action allows for improved statistics accumulation in fixed topological sectors.

Potential applicability to dynamical quark simulations is suggested.

Abstract

We study lattice QCD with a gauge action, which suppresses small plaquette values. Thus the MC history is confined to a single topological sector over a significant time, while other observables are decorrelated. This enables the cumulation of statistics with a specific topological charge, which is needed for simulations of QCD in the $\epsilon$-regime. The same action may also be useful for simulations with dynamical quarks. The update is performed with a local HMC algorithm.