Landau-gauge propagators in Yang-Mills theories at beta = 0: massive solution versus conformal scaling

TL;DR

This study analyzes Landau-gauge gluon and ghost propagators in SU(2) Yang-Mills theories at beta=0, finding strong support for the massive solution with finite gluon propagator and free ghost behavior in the infrared.

Contribution

It provides the first comprehensive lattice comparison at beta=0 for SU(2) in 3D and 4D, favoring the massive solution over conformal scaling.

Findings

Supports the massive solution with finite gluon propagator.

Ghost propagator behaves as essentially free in the infrared.

Discretization effects are negligible in the analysis.

Abstract

We study Landau-gauge gluon and ghost propagators in Yang-Mills theories at lattice parameter beta = 0, considering relatively large lattice volumes for the case of the SU(2) gauge group in three and four space-time dimensions. We compare the lattice data to the so-called massive and conformal-scaling solutions, examining the requirements for a good description of the propagators over various ranges of momenta and discussing possible systematic errors. Our analysis strongly supports the massive solution, i.e. a finite gluon propagator and an essentially free ghost propagator in the infrared limit, in disagreement with Ref. [1]. Moreover, we argue that discretization effects play no role in the analysis of these propagators.