On the Landau-gauge adjoint quark propagator

TL;DR

This paper investigates the Landau-gauge adjoint quark propagator in SU(2) lattice gauge theory, revealing significant differences from fundamental quarks, especially near the chiral limit, with implications for understanding confinement and chiral symmetry.

Contribution

It provides the first detailed lattice study of the adjoint quark propagator in Landau gauge, highlighting its distinct behavior compared to fundamental quarks.

Findings

Pronounced differences in the propagator near the chiral limit.

Distinct behavior observed between quenched and unquenched cases.

Insights into the relation between confinement and chiral symmetry in adjoint quarks.

Abstract

Quarks in the adjoint representation have been a subject of study for both conceptual and practical purposes. Conceptually, their differences when it comes to confining and chiral symmetry properties has long been suspected to hold important information on the relation of these two distinguished properties of QCD-like gauge theories. Practically, they have been studied as both a possibility to access finite density quark systems as well as candidate theories for technicolor in beyond-the-standard-model settings. The most elementary object describing such particles is their propagator, though it being gauge-dependent. Its properties in the minimal Landau gauge are investigated here both in the quenched and unquenched case for a range of lattice parameters using the Wilson formulation for the gauge group SU(2). It is found that the propagator shows pronounced differences to the case of fundamental quarks, especially towards the chiral limit.