Light-Front Aspects of Chiral Symmetry

TL;DR

This paper explores chiral symmetry breaking and anomalies using light-front formulation, demonstrating the role of fermion zero modes and gauge-invariant regularization in simple models and quantum electrodynamics.

Contribution

It introduces a consistent light-front approach to chiral symmetry and anomalies, highlighting the importance of fermion zero modes and gauge-invariant regularization methods.

Findings

Demonstrates multiple vacua and Nambu-Goldstone bosons in a simple sigma model.

Shows the necessity of gauge-invariant point-splitting regularization for anomalies.

Analyzes chiral symmetry and anomalies in the light-front formulation of QED.

Abstract

Spontaneous chiral symmetry breaking and axial anomaly are studied in the light-front formulation. The existence of multiple vacua and a Nambu-Goldstone boson, both related to dynamical fermion zero modes, are demonstrated within a simple sigma model with fermions. The Weyl gauge formulation and a consistent gauge invariant point-splitting regularization, which includes the light front time, are crucial for obtaining the anomaly in the massive Schwinger model and QED(3+1).