Vacuum type of SU(2) gluodynamics in maximally Abelian and Landau gauges

TL;DR

This study uses Monte-Carlo simulations to analyze the vacuum type of SU(2) gluodynamics in different gauges, revealing similar confinement properties and dual superconductor characteristics through measurements of coherence and penetration lengths.

Contribution

It provides a comparative analysis of vacuum properties in maximally Abelian and Landau gauges, including the correlation between monopole density and gluon operators, advancing understanding of dual superconductivity in QCD.

Findings

Dual Meissner effect observed in both gauges.

Coherence and penetration lengths are nearly identical in the two gauges.

Vacuum is near the border between type 1 and type 2 dual superconductors.

Abstract

The vacuum type of SU(2) gluodynamics is studied using Monte-Carlo simulations in maximally Abelian (MA) gauge and in Landau (LA) gauge, where the dual Meissner effect is observed to work. The dual Meissner effect is characterized by the coherence and the penetration lengths. Correlations between Wilson loops and electric fields are evaluated in order to measure the penetration length in both gauges. The coherence length is shown to be fixed in the MA gauge from measurements of the monopole density around the static quark-antiquark pair. It is also shown numerically that a dimension 2 gluon operator A^+A^-(s) and the monopole density has a strong correlation as suggested theoretically. Such a correlation is observed also between the monopole density and A^2(s)= A^+A^-(s) + A^3A^3(s) condensate if the remaining U(1) gauge degree of freedom is fixed to U(1) Landau gauge (U1LA). The coherence length is determined numerically also from correlations between Wilson loops and A^+A^-(s) and A^2(s) in MA + U1LA gauge. Assuming that the same physics works in the LA gauge, we determine the coherence length from correlations between Wilson loops and A^2(s). Penetration lengths and coherence lengths in the two gauges are almost the same. The vacuum type of the confinement phase in both gauges is near to the border between the type 1 and the type 2 dual superconductors.