QCD, monopoles on the Lattice and gauge invariance

TL;DR

This paper demonstrates that monopoles in lattice QCD are gauge invariant objects, and their detection depends on the choice of abelian projection, with numerical evidence supporting this theoretical result.

Contribution

It proves monopoles are gauge invariant in QCD using non-abelian Bianchi identities and analyzes how detection methods depend on abelian projection choices.

Findings

Monopoles are gauge invariant objects in QCD.

Detection methods depend on the choice of abelian projection.

Numerical checks confirm theoretical predictions.

Abstract

The number and the location of the monopoles observed on the lattice in QCD configurations happens to depend strongly on the choice of the gauge used to expose them, in contrast to the physical expectation that monopoles be gauge invariant objects. It is proved by use of the non abelian Bianchi identities (NABI) that monopoles are indeed gauge invariant, but the method used to detect them depends, in a controllable way, on the choice of the abelian projection. Numerical checks are presented.