Non-perturbative corrections in N=2 strings

TL;DR

This paper studies non-perturbative effects in N=2 string theories, comparing heterotic and type IIA dual pairs by calculating R2 corrections, testing duality, and predicting non-perturbative corrections.

Contribution

It provides the first detailed comparison of non-perturbative corrections in heterotic/type IIA dual pairs with N=2 supersymmetry, including instanton effects and duality group analysis.

Findings

Perturbative parts of R2 corrections match, confirming duality.

Type IIA results predict non-perturbative corrections on the heterotic side.

Identified instanton numbers and duality groups for the theories.

Abstract

We investigate the non-perturbative equivalence of some heterotic/type IIA dual pairs with N=2 supersymmetry. We compute R2-like corrections, both on the type IIA and on the heterotic side. The coincidence of their perturbative part provides a test of duality. The type IIA result is then used to predict the full, non-perturbative correction to the heterotic effective action. We determine the instanton numbers and the Olive-Montonen duality groups.