A double scaling limit can be defined in string theory on a Calabi-Yau (CY) manifold by approaching a point in moduli space where the CY space develops an isolated singularity and at the same time… (More)

Target space duality and discrete symmetries in string theory are reviewed in different settings. Email: giveon@vms.huji.ac.il 2 On leave of absence from INFN, sez. di Pisa, Pisa, Italy. Email:… (More)

We review some aspects of the interplay between the dynamics of branes in string theory and the classical and quantum physics of gauge theories with different numbers of supersymmetries in various… (More)

We argue that a class of “non-critical superstring” vacua is holographically related to the (non-gravitational) theory obtained by studying string theory on a singular Calabi-Yau manifold in the… (More)

We propose a framework where the string scale as well as all compact dimensions are at the electroweak scale ∼ TeV−1. The weakness of gravity is attributed to the small value of the string coupling… (More)

We propose a construction of dual pairs in four dimensional N=1 supersymmetric Yang-Mills theory using branes in type IIA string theory. Supersymmetric gauge theories invariant under eight or sixteen… (More)

Some properties of N = 2 superstrings on AdS3 × N are studied. Their spectrum has the same pattern as 2-d CFTs in the moduli space of symmetric products M/Sp, where p is associated with the number of… (More)

We study the exceptional U duality group E d of M-theory compactified on a d−torus and its representations using Matrix theory. We exhibit the E d structure and show that p-branes wrapped or… (More)

We discuss some aspects of the relation between space-time properties of branes in string theory, and the gauge theory on their worldvolume, for models invariant under four supercharges in three and… (More)