Instanton effects and chiral symmetry breaking in QCD2

TL;DR

This paper investigates how instanton configurations influence chiral symmetry breaking in two-dimensional QCD, highlighting the necessity of instantons for nontrivial fermionic correlators and exploring effects for both massless and massive quarks.

Contribution

It demonstrates the essential role of instantons in chiral symmetry breaking in 2D QCD and extends analysis to large N_c with massive quarks.

Findings

Instantons are crucial for nontrivial fermionic correlators.

Chiral symmetry breaking is linked to instanton effects in 2D QCD.

Results apply to both massless and large N_c massive quark regimes.

Abstract

We discuss the spontaneous breakdown of chiral symmetry in Quantum Chromodynamics by considering gluonic instanton configurations in the partition function. It is shown that in order to obtain nontrivial fermionic correlators in a two dimensional gauge theory for the strong interactions among quarks, a regular instanton background has to be taken into account. We work over massless quarks in the -fundamental- representation of SU(N_c). For large N_c, massive quarks are also considered.