Heterotic-Type II String Duality and the H-Monopole Problem

TL;DR

This paper demonstrates that perturbative T-duality combined with heterotic-type II duality implies the existence of heterotic H-monopoles, addressing a key non-perturbative aspect of heterotic string theory.

Contribution

It shows that heterotic H-monopoles can be inferred from known dualities, providing a non-perturbative consistency check within heterotic string theory.

Findings

Heterotic H-monopoles have the correct multiplicity.

Heterotic H-monopoles have the correct multiplet structure.

Construction valid at generic points in moduli space.

Abstract

Since T-duality has been proved only perturbatively and most of the heterotic states map into solitonic, non-perturbative, type II states, the 6-dimensional string-string duality between the heterotic string and the type II string is not sufficient to prove the S-duality of the former, in terms of the known T-duality of the latter. We nevertheless show in detail that perturbative T-duality, together with the heterotic-type II duality, does imply the existence of heterotic H-monopoles, with the correct multiplicity and multiplet structure. This construction is valid at a generic point in the moduli space of heterotic toroidal compactifications.