On the continuum limit of gauge-fixed compact U(1) lattice gauge theory

TL;DR

This paper studies the continuum limit of 4D compact U(1) lattice gauge theory using a nonperturbative gauge fixing, revealing a continuous phase transition and a potential region for nonperturbative continuum physics.

Contribution

It provides the first nonperturbative analysis of the phase structure of gauge-fixed compact U(1) lattice gauge theory in four dimensions, identifying conditions for a continuum limit.

Findings

Evidence of a continuous phase transition for all gauge couplings.

Identification of a region where nonperturbative continuum physics may emerge.

Observation of a chiral transition with quenched fermions at large couplings.

Abstract

We investigate the continuum limit of a compact formulation of the lattice U(1) gauge theory in 4 dimensions using a nonperturbative gauge-fixed regularization. We find clear evidence of a continuous phase transition in the pure gauge theory for all values of the gauge coupling (with gauge symmetry restored). When probed with quenched staggered fermions with U(1) charge, the theory clearly has a chiral transition for large gauge couplings. We identify the only possible region in the parameter space where a continuum limit with nonperturbative physics may appear.