Yutaka Ookouchi

Direct mediation of metastable supersymmetry breaking

The supersymmetric SU(NC) Yang-Mills theory coupled to NF matter fields in the fundamental representation has metastable vacua with broken supersymmetry when NC<NF<(3/2)NC. By gauging the flavor symmetry, this model can be coupled directly to the standard model. We show that it is possible to make a slight deformation to the model so that gaugino masses are generated and the Landau pole problem can be avoided. The deformed model has simple realizations on intersecting branes in string theory, where various features of the metastable vacua are encoded geometrically as brane configurations.

Meta-stable supersymmetry breaking vacua on intersecting branes

We identify configurations of intersecting branes that correspond to the meta-stable supersymmetry breaking vacua in the four-dimensional N = 1 supersymmetric Yang-Mills theory coupled to massive flavors. We show how their energies, the stability properties, and the decay processes are described geometrically in terms of the brane configurations.

Landscape of supersymmetry breaking vacua in geometrically realized gauge theories

Abstract We study vacuum structure of N = 1 supersymmetric quiver gauge theories which can be realized geometrically by D-brane probes wrapping cycles of local Calabi–Yau three-folds. In particular, we show that the A 2 quiver theory with gauge group U ( N 1 ) × U ( N 2 ) with 1 2 N 1 N 2 2 3 N 1 has a regime with an infrared free description that is partially magnetic and partially electric. Using this dual description, we show that the model has a landscape of inequivalent meta-stable vacua where supersymmetry is dynamically broken and all the moduli are stabilized. Each vacuum has distinct unbroken gauge symmetry. The gaugino masses are generated by radiative corrections, and we are left with the bosonic pure Yang–Mills theory in the infrared. We also identify the supersymmetric vacua in this model using their infrared free descriptions and show that the decay rates of the supersymmetry breaking vacua can be made parametrically small.

Supersymmetry Breaking and Gauge Mediation

We review recent works on supersymmetry breaking and gauge mediation. We survey our current understanding of dynamical supersymmetry-breaking mechanisms and describe new model-building tools that use duality, metastability, and stringy construction. We discuss phenomenological constraints and their solutions, paying particular attention to gaugino masses and electroweak symmetry breaking.

Comments on Effective Superpotentials via Matrix Models

Dijkgraaf and Vafa have conjectured that the effective superpotentials for = 1 four-dimensional supersymmetric gauge theories can be given by the planar diagrams of matrix models. We examine some special models with cubic and quartic tree level superpotentials for adjoint chiral superfield Φ. We consider the effective superpotentials for the classical vacuum Φ = 0 for U(N) and SO(N)/Sp(N) gauge theories. We evaluate the effective superpotentials exactly in terms of the matrix model and in terms of closed string theory on Calabi-Yau geometry with fluxes. As a result we find their perfect agreements.

Confining phase superpotentials for SO/Sp gauge theories via geometric transition

We examine a large N duality via geometric transition for = 1 SO/Sp gauge theories with superpotential for adjoint chiral superfield. In this paper, we find that the large N gauge theories are exactly analyzed for the classical quartic superpotentials by the finite rank SO/Sp gauge theories. With this classical superpotentials, we evaluate the confining phase superpotentials using the Seiberg-Witten theory. In the dual theory, we calculate the superpotential generated by the R-R and NS-NS 3-form fluxes. As the non-trivial examples, we discuss for SO(6), SO(8) and Sp(4) gauge theories. In these cases we have the perfect agreement of the confining phase superpotentials up to the 4th order of the glueball superfields.

N = 1 gauge theory with flavor from fluxes

Cachazo and Vafa studied

Gauge Mediation in String Theory

\mathcal{N}=1

Phases of Script N = 1 supersymmetric SO/Sp gauge theories via matrix model

dynamics of U(N) gauge theory from a viewpoint of type IIB superstring compactified on a Calabi-Yau manifold with fluxes. They proved the equivalence between the dynamics and that of

Current Correlators for General Gauge Mediation

\mathcal{N}=2