On the String Landscape Without Hypermultiplets

TL;DR

This paper explores special regions of the quantum gravity landscape with 8 supercharges, revealing constructions without hypermultiplets and analyzing their geometric and quantum properties across various dimensions.

Contribution

It identifies asymmetric orbifold constructions lacking hypermultiplets and examines their origins, including strong coupling effects and violations of geometric conditions.

Findings

Existence of orbifold models without hypermultiplets in 4 and 5 dimensions.

Strong quantum corrections violate Kodaira conditions in certain F-theory limits.

Construction of a 3D theory from pure supergravity with no scalar fields.

Abstract

In this work we study interesting corners of the quantum gravity landscape with 8 supercharges pushing the boundaries of our current understanding. Calabi-Yau threefolds compactifications of F/M/type II theories to 6, 5 and 4 dimensions are the most prominent examples of this class, and these always lead to a universal hypermultiplet coming from the volume/string coupling constant. We find that there are asymmetric orbifold constructions which have no hypermultiplets in 4 or 5 dimensions and no neutral hypers in 6d. We argue that these theories can also be obtained by going to strong coupling/small volume regions of geometric constructions where a new Coulomb branch opens up and moving in this direction freezes the volume/string coupling constant. Interestingly we find that the Kodaira condition encountered in geometric limits of F-theory compactifications to 6 dimensions is violated in these corners of the landscape due to strong quantum corrections. We also construct a theory in 3 dimensions which if it were to arise by toroidal compactifications from 5d, it would have to come from pure ${\mathcal N}=1$ supergravity with no massless scalar fields.