Fermion Sector of Little Higgs

Abstract

The little Higgs mechanism provides an alternative solution to the hierarchy problem, arguably fitting better into the phenomenological hint of the "little hierarchy" which may cause some fine-tuning for the case of supersymmetry. We discuss an aspect of little Higgs physics lacking proper attention -- the construction of an interesting and consistent chiral fermionic sector and its phenomenological implications. At least for the kind of example models to be discussed, the gauge and top sector structure of a model largely dictates, through gauge anomaly cancellation conditions, a specific chiral fermion spectrum. The spectrum has interesting, family non-universal, flavor structure. The implications for flavor physics are specially interesting. We also add a brief comment of little Higgs versus supersymmetry.