String breaking with Wilson loops?

TL;DR

This paper investigates the challenge of observing string breaking through Wilson loops in lattice gauge theory, demonstrating its occurrence in 3D SU(2) and improving potential measurements.

Contribution

It provides the first convincing evidence of string breaking using Wilson loops in 3D SU(2) and enhances the accuracy of static potential measurements.

Findings

String breaking observed in 3D SU(2) with Wilson loops.

Improved measurement of the fundamental SU(2) static potential.

Deviations from Casimir scaling detected.

Abstract

A convincing, uncontroversial observation of string breaking, when the static potential is extracted from Wilson loops only, is still missing. This failure can be understood if the overlap of the Wilson loop with the broken string is exponentially small. In that case, the broken string ground state will only be seen if the Wilson loop is long enough. Our preliminary results show string breaking in the context of the 3d SU(2) adjoint static potential, using the L\"uscher-Weisz exponential variance reduction approach. As a by-product, we measure the fundamental SU(2) static potential with improved accuracy and see clear deviations from Casimir scaling.