Double-Scaling Limit of Heterotic Bundles and Dynamical Deformation in CFT

TL;DR

This paper studies heterotic string theory on Eguchi-Hanson space, revealing a conformal field theory description in a specific limit that connects to deformations of fivebrane backgrounds and highlights non-perturbative effects.

Contribution

It constructs a worldsheet CFT for heterotic strings on Eguchi-Hanson space in a double scaling limit, linking singularity resolution to dynamical deformations of fivebrane backgrounds.

Findings

Identifies a conformal field theory describing heterotic strings near a resolved A_1 singularity.

Shows the role of non-perturbative effects in the spectrum analysis.

Connects the blow-down limit to a dynamical deformation of the fivebrane background.

Abstract

We consider heterotic string theory on Eguchi-Hanson space, as a local model of a resolved A_1 singularity in a six-dimensional flux compactification, with an Abelian gauge bundle turned on and non-zero torsion. We show that in a suitable double scaling limit, that isolates the physics near the non-vanishing two-cycle, a worldsheet conformal field theory description can be found. It contains a heterotic coset whose target space is conformal to Eguchi-Hanson. Starting from the blow-down limit of the singularity, it can be viewed as a dynamical deformation of the near-horizon fivebrane background. We analyze in detail the spectrum of the theory in particular examples, as well as the important role of worldsheet non-perturbative effects.