Kyungho Oh

Orientifold, geometric transition and large N duality for SO / Sp gauge theories

We extend the large N duality of four dimensional = 1 supersymmetric Yang-Mills theory with additional chiral fields and arbitrary superpotential recently proposed by Cachazo, Intriligator and Vafa to the case of SO/Sp gauge groups. By orientifolding the geometric transition, we investigate a large N duality between = 1, SO/Sp supersymmetric theories with arbitrary superpotential and an abelian = 2 theory with supersymmetry broken to = 1 by electric and magnetic Fayet-Iliopoulos terms.

Geometric transition, large N dualities and MQCD dynamics

Abstract We study Vafas geometric transition from a brane setup in M-theory. In this transition D5 branes wrapped on P 1 cycles of a resolved conifold disappear and are replaced by fluxes on a deformed conifold. In the limit of small sized P 1 , we describe this mechanism as a transition from curved M5 branes to plane M5 branes which replaces SU(N) MQCD by U(1) theories on the bulk. This agrees with the results expected from the geometric transition. We also discuss the reduction to ten dimensions and a brane creation mechanism in the presence of fluxes.

Open/Closed String Dualities and Seiberg Duality from Geometric Transitions in M-theory

We propose a general method to study open/closed string dualities from transitions in M theory which is valid for a large class of geometrical configurations. By T-duality we can transform geometrically engineered configurations into = 1 brane configurations and study the transitions of the corresponding branes by lifting the configurations to M-theory. We describe the transformed degenerated M5 branes and extract the field theory information on gluino condensation by factorization of the Seiberg-Witten curve. We also include massive flavors and orientifolds and discuss Seiberg duality which appears in this case as a birational flop. After the transition, the Seiberg duality becomes an abelian electric-magnetic duality.

Geometric transition versus cascading solution

We study Vafas geometric transition and Klebanov-Strassler solution from various points of view in M-theory. In terms of brane configurations, we show the detailed equivalences between the two models. In some limits, both models have an alternative realization as fourfolds in M-theory with appropriate G-fluxes turned on. We discuss some aspects of the fourfolds including how to see the transition and a possible extension to the non-supersymmetric case.

Three dimensional SCFT from M2 branes at conifold singularities

Recently it was conjectured that parallel branes at conical singularities are related to string/M theory on

Renormalization group flows on D3 branes at an orbifolded conifold

AdS \times X

Orbifolds, Penrose limits and supersymmetry enhancement

where

Branes at orbifolded conifold singularities and supersymmetric gauge field theories

X

Branes, geometry and N = 1 duality with product gauge groups of SO and Sp

is an Einstein manifold. In this paper we consider coincident M2 branes near a conifold singularity when M theory is compactified on

Conifolds with discrete torsion and noncommutativity

AdS_4 \times Q^{1,1,1}