Sine-Gordon multi-soliton form factors in finite volume

TL;DR

This paper compares sine-Gordon multi-soliton form factors obtained via bootstrap with finite volume matrix elements calculated through the truncated conformal space approach, confirming their agreement and addressing prior issues.

Contribution

It provides the first detailed comparison between bootstrap form factors and numerical finite volume matrix elements in sine-Gordon theory.

Findings

Convincing agreement between bootstrap and numerical results.

Resolution of previous discrepancies in multi-soliton form factor calculations.

Validation of bootstrap approach for finite volume sine-Gordon models.

Abstract

Multi-soliton form factors in sine-Gordon theory from the bootstrap are compared to finite volume matrix elements computed using the truncated conformal space approach. We find convincing agreement, and resolve most of the issues raised in a previous work.