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

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.