IR-conformal gauge theories and composite Higgs

Abstract

The existence of non-trivial IR and UV fixed points in gauge theories as a function of the number of fermion flavors and bare coupling is discussed in the light of recent work. It is pointed out that in fact only a small subset of potential IR-conformal gauge theories, i.e. theories whose IR behavior is determined by an IR fixed point, has so far been examined. Recent lattice computations of the spectrum in some cases where existence of an IR fixed point is reasonably assured, however, reveal a non-QCD-like spectrum with the lightest states being scalars. It is suggested that these naturally light composite scalars provide a natural setting for the construction of new composite Higgs models. A schematic outline of such a model is given.