Comparison of complex Langevin and mean field methods applied to effective Polyakov line models

Understand

Effective Polyakov line models, derived from SU(3) gauge-matter systems at finite chemical potential, have a sign problem.

• In this article I solve two such models, derived from SU(3) gauge-Higgs and heavy quark theories by the relative weights method, over a range of chemical potentials where the sign problem is severe.
• Two values of the gauge-Higgs coupling are considered, corresponding to a heavier and a lighter scalar particle.
• Each model is solved via the complex Langevin method, following the approach of Aarts and James, and also by a mean field technique.