A Universal Constraint on the Infrared Behavior of the Ghost Propagator in QCD

TL;DR

This paper derives a new identity for the quark-gluon interaction vertex in QCD, establishing a universal constraint that the ghost propagator's dressing function approaches a constant in the infrared limit, impacting our understanding of gauge theories.

Contribution

It introduces a novel gauge-symmetry-based identity for the quark-gluon vertex, providing a universal constraint on ghost propagator behavior in the infrared regime.

Findings

Ghost dressing function approaches a constant at zero momentum.

Provides a strong theoretical constraint on infrared ghost behavior.

Enhances understanding of gauge symmetry implications in QCD.

Abstract

With proposing a unified description of the fields variation at the level of generating functional, we obtain a new identity for the quark-gluon interaction vertex based on gauge symmetry, which is similar to the Slavnov-Taylor Identities(STIs) based on the Becchi-Rouet-Stora-Tyutin transformation. With these identities, we find that in Landau gauge, the dressing function of the ghost propagator approaches to a constant as its momentum goes to zero, which provides a strong constraint on the infrared behaviour of ghost propagator.