On the infrared behavior of Landau gauge Yang-Mills theory

TL;DR

This paper investigates the infrared behavior of ghost and gluon propagators in Landau gauge Yang-Mills theory, showing that boundary conditions determine whether scaling or decoupling occurs, with implications for confinement.

Contribution

It demonstrates that the infrared behavior depends on boundary conditions and argues that decoupling conflicts with BRST symmetry, improving truncation schemes in Dyson-Schwinger and functional renormalization group analyses.

Findings

Infrared scaling or decoupling depends on boundary conditions.

Decoupling phase conflicts with BRST symmetry.

Enhanced truncation schemes improve analysis accuracy.

Abstract

We discuss the properties of ghost and gluon propagators in the deep infrared momentum region of Landau gauge Yang-Mills theory. Within the framework of Dyson-Schwinger equations and the functional renormalization group we demonstrate that it is only a matter of infrared boundary conditions whether infrared scaling or decoupling occurs. We argue that the second possibility is at odds with global BRST symmetry in the confining phase. For this purpose we improve upon existing truncation schemes in particular with respect to transversality and renormalization.