A dynamical mechanism for generating quark confinement

TL;DR

This paper proposes a gauge-invariance-based dynamical mechanism in QCD that explains how an infrared singular quark-gluon vertex leads to quark confinement and links it with chiral symmetry breaking.

Contribution

It introduces a novel gauge-invariance constraint that explains the infrared behavior of the quark-gluon vertex and its role in quark confinement.

Findings

Infrared singular quark-gluon vertex generates a linear confining potential.

Infrared behavior of form factors in the quark-ghost scattering kernel is crucial.

Link between chiral symmetry breaking and quark confinement is established.

Abstract

We explore the dynamical mechanism for generating the infrared singular quark-gluon vertex and quark confinement based on the gauge invariance in covariant-gauge quantum chromodynamics(QCD). We first derive the gauge-invariance constraint relation for the infrared-limit behavior of the quark-gluon vertex, which shows the mechanism for generating the infrared behavior of the quark-gluon vertex. We hence unravel a novel mechanism for generating an infrared singular quark-gluon vertex and then a linear rising potential for confining massive quarks, where the infrared singularity in the form factors composing the quark-ghost scattering kernel plays a crucial role. The mechanism for linking chiral symmetry breaking with quark confinement is also shown.