On practical problems to compute the ghost propagator in SU(2) lattice gauge theory

TL;DR

This paper investigates how Gribov copies affect the ghost propagator in SU(2) lattice gauge theory, revealing their significance at certain scales and challenges at higher beta values due to fluctuations.

Contribution

It provides a numerical analysis of Gribov copy effects on the ghost propagator across different beta values in SU(2) lattice gauge theory.

Findings

Gribov copies significantly influence the ghost propagator in the scaling window.

The impact of Gribov copies diminishes as beta increases.

Large beta values introduce strong fluctuations complicating calculations.

Abstract

In SU(2) lattice pure gauge theory we study numerically the dependence of the ghost propagator G(p) on the choice of Gribov copies in Lorentz (or Landau) gauge. We find that the effect of Gribov copies is essential in the scaling window region, however, it tends to decrease with increasing beta. On the other hand, we find that at larger beta-values very strong fluctuations appear which can make problematic the calculation of the ghost propagator.