Ak F ¯ chiral gauge theories Ak F ¯ chiral gauge theories Yan-Liang Shi and Robert Shrock

We study asymptotically free chiral gauge theories with an SU(N) gauge group and chiral fermions transforming according to the antisymmetric rank-k tensor representation, Ak≡[k]N, and the requisite number, nF¯, of copies of fermions in the conjugate fundamental representation, F¯≡[1]¯N, to render the theories anomaly-free. We denote these as AkF¯ theories. We take N≥2k+1 so that nF¯≥1. The A2F¯ theories form an infinite family with N≥5, but we show that the A3F¯ and A4F¯ theories are only asymptotically free for N in the respective ranges 7≤N≤17 and 9≤N≤11, and that there are no asymptotically free AkF¯ theories with k≥5. We investigate the types of ultraviolet to infrared evolution for these AkF¯ theories and find that, depending on k and N, they may lead to a non-Abelian Coulomb phase, or may involve confinement with massless gauge-singlet composite fermions, bilinear fermion condensation with dynamical gauge and global symmetry breaking, or formation of multifermion condensates that preserve the gauge symmetry. We also show that there are no asymptotically free, anomaly-free SU(N) SkF¯ chiral gauge theories with k≥3, where Sk denotes the rank-k symmetric representation.