Regular Seminar Anthony Ashmore (Imperial College)
room G.O. Jones 610
Calabi-Yau manifolds without flux are perhaps the best-known supergravity backgrounds that leave some supersymmetry unbroken. The supersymmetry conditions on such spaces can be rephrased as the existence and integrability of a particular geometric structure. When fluxes are allowed, the conditions are more complicated and the analogue of the geometric structure is not well understood. In this talk, I will define the analogue of Calabi-Yau geometry for generic D=4, N=2 backgrounds with flux in both type II and eleven-dimensional supergravity. The geometry is characterised by a pair of G-structures in 'exceptional generalised geometry' that interpolate between complex, symplectic and hyper-Kahler geometry. Supersymmetry is then equivalent to integrability of the structures, which appears as moment maps for diffeomorphisms and gauge transformations. Similar structures also appear in D=5 and D=6 backgrounds with eight supercharges. As a simple application, I will discuss the case of AdS5 backgrounds in type IIB, where deformations of these geometric structures give exactly marginal deformations of the dual field theories.