Holographic MQCD

Abstract

We study a brane configuration of D4-branes and NS5-branes in weakly coupled type IIA string theory, which describes in a particular limit d=4 N=1 SU(N+p) supersymmetric QCD with 2N flavors and a quartic superpotential. We describe the geometric realization of the supersymmetric vacuum structure of this gauge theory. We focus on the confining vacua of the gauge theory, whose holographic description is given by the MQCD brane configuration in the near-horizon geometry of N D4-branes. This description, which gives an embedding of MQCD into a field theory decoupled from gravity, is valid for 1 << p << N, in the limit of large five dimensional `t Hooft couplings for the color and flavor groups. We analyze various properties of the theory in this limit, such as the spectrum of mesons, the finite temperature behavior, and the quark-anti-quark potential. We also discuss the same brane configuration on a circle, where it gives a geometric description of the moduli space of the Klebanov-Strassler cascading theory, and some non-supersymmetric generalizations.