Type IIA Dual of the Six-Dimensional CHL Compactification

TL;DR

This paper proposes a duality between a six-dimensional heterotic string compactification and a specific type IIA string theory setup involving orbifolds and fluxes, illustrating a novel non-standard dual background.

Contribution

It introduces a new candidate dual for a six-dimensional heterotic compactification involving orbifolds and fluxes, expanding the understanding of string dualities.

Findings

Constructs a type IIA dual with orbifold and flux features.

Shows the dual background differs from standard super-conformal backgrounds.

Provides explicit example of non-standard duality in string theory.

Abstract

We propose a candidate for the dual (in the weak/strong coupling sense) of the six-dimensional heterotic string compactification constructed recently by Chaudhuri, Hockney and Lykken. It is a type IIA string theory compactified on an orbifold $K3/Z_2$, where the $Z_2$ action involves an involution of $K3$ with fixed points, and also has an embedding in the U(1) gauge group associated with the Ramond-Ramond sector of the type IIA string theory. This introduces flux of the U(1) gauge field concentrated at the orbifold points. This construction provides an explicit example where the dual of a super-conformal field theory background of the heterotic string theory is not a standard super-conformal field theory background of the type IIA string theory.