Lattice studies of QCD-like theories with many fermionic degrees of freedom

Abstract

I give an elementary introduction to the study of gauge theories coupled to fermions with many degrees of freedom. Besides their intrinsic interest, these theories are candidates for nonperturbative extensions of the Higgs sector of the Standard Model. While related to QCD, these systems can exhibit very different behavior from it: they can possess a running gauge coupling with an infrared attractive fixed point (IRFP). I briefly survey recent lattice work in this area.