Effective Action in a General Chiral Model: Next to Leading Order Derivative Expansion in the Worldline Method

TL;DR

This paper introduces a formalism using worldline path integrals to compute the imaginary part of the effective action in general chiral models, incorporating anomalies and covariant currents.

Contribution

It develops a novel worldline-based method to evaluate the effective action's imaginary part in chiral models at next-to-leading order.

Findings

Provides explicit covariant form of the covariant current

Enables calculation of the imaginary part of the effective action

Incorporates anomaly considerations in the formalism

Abstract

We present a formalism to determine the imaginary part of a general chiral model in the derivative expansion. Our formalism is based on the worldline path integral for the covariant current that can be given in an explicit chiral and gauge covariant form. The effective action is then obtained by integrating the covariant current, taking account of the anomaly.