Nonsupersymmetric Seiberg duality, orientifold QCD, and noncritical strings

Abstract

We propose an electric-magnetic duality and conjecture an exact conformal window for a class of nonsupersymmetric $U({N}_{c})$ gauge theories with fermions in the (anti)symmetric representation of the gauge group and ${N}_{f}$ additional scalar and fermion flavors. The duality exchanges ${N}_{c}\ensuremath{\rightarrow}{N}_{f}\ensuremath{-}{N}_{c}\ensuremath{\mp}4$ leaving ${N}_{f}$ invariant, and has common features with Seiberg duality in $\mathcal{N}=1$ super QCD (SQCD) with $SU$ or $SO/Sp$ gauge group. At large $N$ the duality holds due to planar equivalence with $\mathcal{N}=1$ SQCD. At finite $N$ we embed these gauge theories in a setup with D-branes and orientifolds in a nonsupersymmetric, but tachyon-free, noncritical type 0B string theory and argue in favor of the duality in terms of boundary and crosscap state monodromies as in analogous supersymmetric situations. One can verify explicitly that the resulting duals have matching global anomalies. Finally, we comment on the moduli space of these gauge theories and discuss other potential nonsupersymmetric examples that could exhibit similar dualities.