Integrable Extension of Nonlinear Sigma Model

TL;DR

This paper introduces an integrable extension of the nonlinear sigma model on Hermitian symmetric spaces, utilizing the coadjoint orbit method to establish a covariant structure and derive infinite conservation laws.

Contribution

It develops a novel integrable extension of the nonlinear sigma model on HSS using the coadjoint orbit method and covariant structures, enabling zero curvature representation.

Findings

Constructed integrable models on arbitrary HSS

Derived infinite conservation laws for nonlocal charges

Established zero curvature representation for the extended model

Abstract

We propose an integrable extension of nonlinear sigma model on the target space of Hermitian symmetric space (HSS). Starting from a discussion of soliton solutions of O(3) model and an integrally extended version of it, we construct general theory defined on arbitrary HSS by using the coadjoint orbit method. It is based on the exploitation of a covariantized canonical structure on HSS. This term results in an additional first-order derivative term in the equation of motion, which accommodates the zero curvature representation. Infinite conservation laws of nonlocal charges in this model are derived.