On full-fledged supergravity cosmologies and their Weyl group asymptotics

Abstract

We consider a class of cosmological solutions of d=4, N=2 supergravity theories coupled to vector multiplets. The solutions result from performing a compactification to three dimensions, where the theory reduces to a symmetric space sigma model coupled to gravity and where the resulting equations of motion are integrable. We describe in detail how the three-dimensional solutions can be uplifted to four dimensions again. The four-dimensional cosmologies are generically characterized by an algebra of translational isometries that is of Heisenberg type. We give explicit examples of these cosmologies for the S-T-U model and comment also on their uplift to 10 dimensions by interpreting them as solutions of a truncation of type IIB supergravity on a K3 x T^2/Z_2 orientifold.