Confinement from semiclassical gluon fields in SU(2) gauge theory

TL;DR

This paper investigates the infrared structure of SU(2) Yang-Mills theory using a novel lattice simulation technique that preserves confinement and reveals semiclassical configurations with topological and chiral properties.

Contribution

It introduces a constrained cooling method that maintains confinement while reducing action, revealing semiclassical configurations with a cluster structure and topological features.

Findings

Confinement persists after constrained cooling.

Semiclassical configurations support topological susceptibility.

Clusters are mainly (anti-)selfdual with smoothly distributed topological charge.

Abstract

The infrared structure of SU(2) Yang-Mills theory is studied by means of lattice gauge simulations using a new constrained cooling technique. This method reduces the action while all Polyakov lines on the lattice remain unchanged. In contrast to unconstrained cooling, quark confinement is still intact. A study of the Hessian of the Yang-Mills action shows that low action (semi-) classical configurations can be achieved, with a characteristic splitting between collective modes and higher momentum modes. Besides confinement, the semiclassical configurations also support the topological susceptibility and generate spontaneous breakdown of chiral symmetry.We show that they possess a cluster structure of locally mainly (anti-) selfdual objects. By contrast to an instanton or a meron medium, the topological charge of individual clusters is smoothly distributed.