Flowing Gauge Theories: Finite-Density $QED_{1+1}$

TL;DR

This paper explores the use of holomorphic flow equations to mitigate sign problems in finite-density lattice gauge theories, demonstrating their application to $QED_{1+1}$ and revealing novel features of the method.

Contribution

It introduces a new approach using holomorphic flow equations to improve finite-density calculations in gauge theories, with specific results for $QED_{1+1}$.

Findings

Flow equations reduce sign fluctuations in finite-density $QED_{1+1}$

Novel features of applying flow equations to gauge theories

Potential for broader application in lattice field theory

Abstract

Finite-density calculations in lattice field theory are typically plagued by sign problems. A promising way to ameliorate this issue is the holomorphic flow equations that deform the manifold of integration for the path integral to manifolds in the complex space where the sign fluctuations are less dramatic. We discuss some novel features of applying the flow equations to gauge theories and present results for finite-density $QED_{1+1}$.