The Form Factor Program: a Review and New Results - the Nested SU(N) Off-Shell Bethe Ansatz

TL;DR

This paper reviews the bootstrap approach for integrable quantum field theories in 1+1 dimensions, illustrating it with models like sinh-Gordon and SU(N) Gross-Neveu, and introduces a nested off-shell Bethe ansatz for SU(N).

Contribution

It presents a new nested off-shell Bethe ansatz method for SU(N) factorizing S-matrices, advancing the explicit construction of models within the bootstrap program.

Findings

Constructed the nested off-shell Bethe ansatz for SU(N) S-matrix.

Reviewed form factors and operator equations for sinh-Gordon model.

Analyzed the short distance behavior of two-point functions.

Abstract

The purpose of the ''bootstrap program'' for integrable quantum field theories in 1+1 dimensions is to construct explicitly a model in terms of its Wightman functions. In this article, this program is mainly illustrated in terms of the sinh-Gordon model and the SU(N) Gross-Neveu model. The nested off-shell Bethe ansatz for an SU(N) factorizing S-matrix is constructed. We review some previous results on sinh-Gordon form factors and the quantum operator field equation. The problem of how to sum over intermediate states is considered in the short distance limit of the two point Wightman function for the sinh-Gordon model.