My research explores various aspects of the AdS/ CFT correspondence, including giant gravitons and pp-waves. I also study topological string theory. Topological string theory counts the number of holomorphic curves in Calabi-Yau space, a problem of great interest in the mathematics of algebraic geometry. Finally, I am interested in the applications of string theory to cosmology and particle physics. Some of my recent works with collaborators study the non-Gaussian feature in the anisotropy of the Cosmic Microwave Background (CMB) in various inflationary models inspired by string theory constructions.