Noncritical-Topological Correspondence: Disc Amplitudes and Noncompact Branes

TL;DR

This paper explores the duality between type 0 noncritical strings and topological B-model strings, focusing on flux dependence and the role of noncompact branes in holomorphic factorisation and disc amplitudes.

Contribution

It precisely defines the B-model dual including both compact and noncompact branes, explaining their roles in holomorphic factorisation and disc terms, and extends the analysis to rational radii.

Findings

Noncompact B-branes contribute disc terms that violate holomorphic factorisation.

The duality is generalized to rational radii with nonperturbative results.

The framework extends to a topological-anti-topological correspondence.

Abstract

We examine the duality between type 0 noncritical strings and topological B-model strings, with special emphasis on the flux dependence. The former theory is known to exhibit holomorphic factorisation upto a subtle flux-dependent disc term. We give a precise definition of the B-model dual and propose that it includes both compact and noncompact B-branes. The former give the factorised part of the free energy, while the latter violate holomorphic factorisation and contribute the desired disc term. These observations are generalised to rational radii, for which we derive a nonperturbatively exact result. We also show that our picture extends to a proposed alternative topological-anti-topological picture of the correspondence for type 0 strings.