The proposed research covers a wide range of topics in superstring theory and phenomenology. The main focus will be in non-Abelian generalizations of the Born-Infeld theory describing the SO (32) gauge boson excitations of Type I open Superstrings. Dualities will be used to analyze the effective action of these theories. Duality techniques will also be applied to understanding questions of superstring phenomenology such as supersymmetry breaking and mass generation with the purpose of obtaining testable prediction for present and future collider experiments. Among these predictions will be predictions of gaugino condensation mechanisms for understanding tan b and to understand cascades of supersymmetry breaking and their experimental consequences.
