We investigate backgrounds of Type IIB string theory with null singularities and their duals
proposed in SR Das, J. Michelson, K. Narayan, SP Trivedi, hep-th/0602107. The dual theory …

These proceedings are based on lectures delivered at the'RTN Winter School on Strings,
Supergravity and Gauge Theories', CERN, 16–20 January 2006. The school was mainly …

We construct cosmological spacetimes with null Kasner-like singularities as purely
gravitational solutions with no other background fields turned on. These can be recast as …

We construct a fairy general family of supersymmetric solutions in time-and space-
dependent backgrounds in general supergravity theories. One class of the solutions are …

We construct a family of supersymmetric solutions in time-dependent backgrounds in
supergravity theories. One class of the solutions are intersecting brane solutions and …

We construct a general family of supersymmetric solutions in time-and space-dependent
wave backgrounds in general supergravity theories describing single and intersecting p …

We compute correlation functions of closed strings in Misner space, which is a big
crunch/big bang universe. We develop a general method for correlators with twist fields …

We present a class of low energy type IIB supergravity solutions of two D3-branes rotated by
an angle α∈ SU (2) in a linear dilaton pp-wave background. The D-branes bound state …

We construct a general family of supersymmetric solutions in time-and space-dependent
wave backgrounds in general supergravity theories describing single and intersecting p …