Topological defects in open string field theory

TL;DR

This paper explores how topological defects in conformal field theory can connect different solutions in open string field theory, revealing a novel algebraic structure and generalizing previous results to include boundary condition changes.

Contribution

It introduces a generalized framework for defect actions on boundary condition changing fields, including cases with nontrivial multiplicities, and demonstrates the defect fusion algebra's realization on open string fields.

Findings

Defects relate solutions with different boundary conditions.

Fusion algebra of defects is realized up to a star algebra isomorphism.

Generalization of Graham and Watts' results to include multiplicities.

Abstract

We show how conformal field theory topological defects can relate solutions of open string field theory for different boundary conditions. To this end we generalize the results of Graham and Watts to include the action of defects on boundary condition changing fields. Special care is devoted to the general case when nontrivial multiplicities arise upon defect action. Surprisingly the fusion algebra of defects is realized on open string fields only up to a (star algebra) isomorphism.