Moduli stabilization and cosmology of type IIB on SU(2)-structure orientifolds

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 is an element of numerically zero. However, the point has two tachyons and eta-parameter eta approximate to -3.1.