Yang-Mills propagators in linear covariant gauges from Nielsen identities

Abstract

We calculate gluon and ghost propagators in Yang-Mills theory in linear covariant gauges. To that end, we utilise Nielsen identities with Landau gauge propagators and vertices as the starting point. We present and discuss numerical results for the gluon and ghost propagators for values of the gauge parameter 0 < ξ ≤ 5. Extrapolating the propagators to ξ → ∞ we find the expected qualitative behavior. We provide arguments that our results are quantitatively reliable at least for values ξ 1/2 of the gauge fixing parameter. It is shown that the correlation functions, and in particular the ghost propagator, change significantly with increasing gauge parameter. In turn, the ghost-gluon running coupling as well as the position of the zero crossing of the Schwinger function of the gluon propagator remain within the uncertainties of our calculation unchanged.

An all order renormalizable Refined-Gribov-Zwanziger model with BRST invariant fermionic horizon function in linear covariant gauges

“…• the Nielsen identities also imply that the longitudinal component of the gluon propagator does not get any quantum correction to all orders, a property shared also by the studies of the LCG gauge within the Schwinger-Dyson framework [39,40] as well as by lattice numerical simulations [41][42][43],…”

Polyakov loop, gluon mass, gluon condensate and its asymmetry near deconfinement

“…Because the decoupling behavior as observed on the lattice extends beyond the Landau gauge to linear covariant gauges [56,57], it will be important to make sure that the dynamical mass generation mechanism applies independently of the gauge-fixing parameter. Moreover, for the dynamically generated mass to carry a physical significance, it should be associated to a BRST invariant gluon condensate.…”