Duality and Infinite Distance Limits in Asymmetric Freely Acting Orbifolds

TL;DR

This paper constructs four-dimensional string theories using asymmetric orbifolds, revealing new infinite distance points in moduli space where theories decompactify, thus supporting the distance conjecture in non-geometric compactifications.

Contribution

It introduces a class of asymmetric orbifold models with modified duality groups and explores their infinite distance limits, providing evidence for the distance conjecture in non-geometric string compactifications.

Findings

Identification of infinite distance points in moduli space.

Verification of the distance conjecture in non-geometric backgrounds.

Discovery of decompactification points to different orbifold theories.

Abstract

We use freely acting asymmetric orbifolds of type IIB string theory to construct a class of theories in four dimensions with eight supercharges. Their low energy effective field theories resemble $STU$ models, but have different duality groups: the orbifold's free action reduce the duality groups to congruence subgroups of the modular group. The fundamental domain is consequently larger and contains new interesting points at infinite distance on the real axis bounding the upper half plane. We verify that the distance conjectures hold in the non-geometric compactification of string theory studied here. In particular, we find points at infinite distance in moduli space at which the theory decompactifies to a different orbifold construction.