Exotic Non-Supersymmetric Gauge Dynamics from Supersymmetric QCD

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We extend Seiberg's qualitative picture of the behavior of supersymmetric QCD to nonsupersymmetric models by adding soft supersymmetry breaking terms. In this way, we recover the standard vacuum of QCD with Nf flavors and Nc colors when Nf < Nc. However, for Nf ≥ Nc, we find new exotic states---new vacua with spontaneously broken baryon number for Nf = Nc, and a vacuum state with unbroken chiral symmetry for Nf > Nc. These exotic vacua contain massless composite fermions and, in some cases, dynamically generated gauge bosons. In particular Seiberg's electric-magnetic duality seems to persist also in the presence of (small) soft supersymmetry breaking. We argue that certain, specially tailored, lattice simulations may be able to detect the novel phenomena. Most of the exotic behavior does not survive the decoupling limit of large SUSY breaking parameters.