Moduli Stabilization and Cosmology of Type IIB on SU(2)-Structure Orientifolds

TL;DR

This paper explores type IIB flux compactifications on SU(2)-structure manifolds, deriving the scalar potential, stabilizing moduli, and establishing no-go theorems that restrict the existence of de Sitter vacua and inflation.

Contribution

It provides the first explicit example of a fully stabilized AdS vacuum with large volume and small string coupling in this setting, and formulates no-go theorems for dS vacua and inflation.

Findings

Constructed a fully stabilized AdS vacuum with large volume

Derived no-go theorems forbidding dS vacua and slow-roll inflation

Found a dS critical point with tachyons and negative eta in a specific example

Abstract

We consider type IIB flux compactifications on six-dimensional SU(2)-structure manifolds with O5- and O7-planes. These six-dimensional spaces allow not only for F_3 and H_3 fluxes but also for F_1 and F_5 fluxes. We derive the four-dimensional N=1 scalar potential for such compactifications and present one explicit example of a fully stabilized AdS vacuum with large volume and small string coupling. We then discuss cosmological aspects of these compactifications and derive several no-go theorems that forbid dS vacua and slow-roll inflation under certain conditions. We also study concrete examples of cosets and twisted tori and find that our no-go theorems forbid dS vacua and slow-roll inflation in all but one of them. For the latter we find a dS critical point with \epsilon numerically zero. However, the point has two tachyons and eta-parameter \eta \approx -3.1.