We study the boundary states of D-branes wrapped around supersym-metric cycles in a general Calabi-Yau manifold. In particular, we show how the geometric data on the cycles are encoded in theâ€¦ (More)

We construct supergravity solutions that correspond to N Dp-branes coinciding with N Dp-branes. We study the physical properties of the solutions and analyse the supergravity description of tachyonâ€¦ (More)

We calculate the spectrum of glueball masses in non-supersymmetric YangMills theory in three and four dimensions, based on a conjectured duality between supergravity and large N gauge theories. Theâ€¦ (More)

We derive in the SCFT and low energy effective action frameworks the necessary and sufficient conditions for supersymmetric cycles in exceptional holonomy manifolds and Calabi-Yau 4-folds. We showâ€¦ (More)

We consider systems of Dp-branes in the presence of a nonzero B field. We study the corresponding supergravity solutions in the limit where the branes worldvolume theories decouple from gravity.â€¦ (More)

It has been known that the fivebrane of type IIA theory can be used to give an exact low energy description of N = 2 supersymmetric gauge theories in four dimensions. We follow the recent M-theoryâ€¦ (More)

We construct and analyze dual N = 4 supersymmetric gauge theories in three dimensions with unitary and symplectic gauge groups. The gauge groups and the field content of the theories are encoded inâ€¦ (More)

We use brane configurations and SL(2, Z) symmetry of the type IIB string to construct mirror N = 2 supersymmetric gauge theories in three dimensions. The mirror map exchanges Higgs and Coulombâ€¦ (More)

We use the Konishi anomaly equations to construct the exact effective superpotential of the glueball superfields in various N = 1 supersymmetric gauge theories. We use the superpotentials to study inâ€¦ (More)

We use the superspace method of hep-th/0211017 to prove the matrix model conjecture for N=1 USp(N) and SO(N) gauge theories in four dimensions. We derive the prescription to relate the matrix modelâ€¦ (More)