fermion: representation

Finite-temperature phase structure of SU(4) gauge theory with multiple fermion representations

We investigate the phase structure of SU(4) gauge theory with the gauge field simultaneously coupled to two flavors of fermions in the fundamental representation and two flavors of fermions in the two-index antisymmetric representation. We find that …

Spectroscopy of SU(4) composite Higgs theory with two distinct fermion representations

We have simulated the SU(4) lattice gauge theory coupled to dynamical fermions in the fundamental and two-index antisymmetric (sextet) representations simultaneously. Such theories arise naturally in the context of composite Higgs models that include …

One-loop Chiral Perturbation Theory with two fermion representations

We develop chiral perturbation theory for chirally broken theories with fermions in two different representations of the gauge group. Any such theory has a nonanomalous singlet U(1)A symmetry, yielding an additional Nambu-Goldstone boson when …