Center vortices and the emergence of a gluon mass scale

TL;DR

The paper addresses how gauge-invariant field-strength correlators can exhibit massive-like IR behavior in a confining Yang-Mills vacuum. It adopts an Abelian-projected wavefunctional peaked on networks of center vortices and monopoles, and computes gauge-invariant two-point correlators in momentum space. The main result is that the mixed ensemble of oriented and nonoriented center vortices induces a mass scale $m$ in electric and magnetic correlators, with explicit IR expressions showing massive-like suppression, while preserving confinement through the center-vortex mechanism that yields area law and Casimir scaling. This work bridges center-vortex content with gauge-invariant correlators, offering a concrete mechanism for coexistence of a gluon mass scale and confinement, and suggests testable IR signatures in the field-strength correlators.

Abstract

Lattice simulations and theoretical analyses consistently identify center vortices and monopoles as key nonperturbative configurations in Yang-Mills theory. Independently, studies of correlation functions reveal an infrared behavior characterized by massive-like scales. Yet, an open issue is how such correlators can arise in a confining regime characterized by a linearly rising potential rather than a Yukawa one. Using an Abelian-projected vacuum wavefunctional peaked on chains formed by center vortices and monopoles, we compute gauge-invariant field-strength correlators. We show the emergence of a massive-like correlator constructed from the gauge-invariant two-point field strength observable. This behavior arises from the nonoriented soft component of the center-vortex condensate, the same hierarchical mechanism previously shown to produce the area law and Casimir scaling of string tensions.