%0 Journal Article %T Duality in Topological Quantum Field Theories %A Carlos Lozano %J Physics %D 1999 %I arXiv %X This thesis presents a thorough analysis of the links between the N=4 supersymmetric gauge theory in four dimensions and its three topological twisted counterparts. Special emphasis is put in deriving explicit results in terms of the vacuum structure and low-energy effective description of four-dimensional supersymmetric gauge theories. A key ingredient is the realization of Montonten-Olive duality in the twisted theories, which is discussed in detail from different viewpoints. %U http://arxiv.org/abs/hep-th/9907123v2