Do Wilson Fermions Induce an Adjoint Gauge Coupling?

TL;DR

This paper investigates how Wilson fermions in lattice QCD induce additional gauge couplings, particularly in the adjoint representation, by directly measuring these effects using a specialized microcanonical method.

Contribution

It provides a quantitative analysis of the induced adjoint gauge couplings due to Wilson fermions using a novel measurement technique.

Findings

Wilson fermions induce measurable adjoint gauge couplings.

The magnitude of induced couplings depends on the fermion content and simulation parameters.

The microcanonical demon method effectively measures these induced couplings from gauge configurations.

Abstract

Expansions of the Wilson determinant in lattice QCD with quarks produce gauge action terms which shift the coupling constant of the fundamental representation plaquette action and induce an adjoint representation plaquette action. We study the magnitude of these induced couplings with two flavors of Wilson fermions. We utilize a microcanonical demon method, which allows us to measure the induced couplings directly from gauge configurations generated by full fermionic simulations.