Meta-Stable Vacua in

This masters thesis discusses some aspects of four dimensional super-symmetric gauge theories. More specifically, it discusses a method to break supersymmetry spontaneously in certain gauge theories in a way that bypasses some phenomenological problems. We start by giving a short introduction to supersymmetry and spon-taneous supersymmetry breaking. We then discuss a supersymmetric version of QCD and the phenomenon of Seiberg duality. Using these tools we show, following K. Intriligator, N. Seiberg and D. Shih, that supersymmetric QCD has a supersymmetry breaking metastable vac-uum for certain number of flavors. We conclude by showing that this metastable vacuum can be made parametrically long lived. Acknowledgments First of all, I would like to express my gratitude to my supervisor Gabriele Ferretti for introducing me to the fascinating world of Super