Supersymmetric Gauge Theories from String Theory
  The subject of this thesis are various ways to construct four-dimensional quantum field theories from string theory. In a first part we study the generation of a supersymmetric Yang-Mills theory, coupled to an adjoint chiral superfield, from type IIB string theory on non-compact Calabi-Yau manifolds, with D-branes wrapping certain subcycles. The low energy limit of this non-Abelian gauge theory can be obtained from a second non-compact Calabi-Yau geometry, which is related to the first one through a geometric transition. In particular, the effective superpotential governing the vacuum structure of the gauge theory can be obtained from integrals on a Calabi-Yau manifold. These integrals in turn are related to matrix model quantities and one therefore can use the matrix model to learn something about the gauge theory vacua. The second part of this work covers the generation of four-dimensional supersymmetric gauge theories, carrying several important characteristic features of the standard model, from compactifications of eleven-dimensional supergravity on G_2-manifolds. We discuss anomaly cancellation through inflow in the case of conical singularities, present an explicit compact manifold with two conical singularities and weak G_2-holonomy, and review the anomaly cancellation mechanism in the context of M-theory on the interval. 
Steffen Metzger