Gluon and ghost correlation functions of 2-color QCD at finite density

TL;DR

This study computes gluon and ghost correlation functions in 2-color QCD at finite density, providing benchmarks for non-perturbative approaches and observing minimal effects except for low-momentum gluon screening.

Contribution

It offers the first lattice determination of minimal-Landau-gauge correlation functions and the running gauge coupling of 2-color QCD at finite density.

Findings

No significant effects on correlation functions except low-momentum screening

Gluon screening observed at and above the phase transition

Provides benchmarks for non-perturbative methods in finite density QCD

Abstract

2-color QCD, i. e. QCD with the gauge group SU(2), is the simplest non-Abelian gauge theory without sign problem at finite quark density. Therefore its study on the lattice is a benchmark for other non-perturbative approaches at finite density. To provide such benchmarks we determine the minimal-Landau-gauge 2-point and 3-gluon correlation functions of the gauge sector and the running gauge coupling at finite density. We observe no significant effects, except for some low-momentum screening of the gluons at and above the supposed high-density phase transition.