More exact results on chiral gauge theories: The case of the symmetric tensor

We study dynamics of SU(N-4) gauge theories with fermions in rank-2 symmetric tensor and N antifundamental representations, by perturbing supersymmetric theories with anomaly-mediated supersymmetry breaking. We find the SU(N)×U(1) global symmetry is dynamically broken to $SO(N)$ for N≥17, a different result from conjectures in the literature. For $N<17$, the theory initially flows to a superconformal fixed point, but is diverted by the soft masses, which act as a relevant perturbation.