Flavor and Little Higgs

TL;DR

This paper explores how constructing anomaly-free fermionic spectra in little Higgs models impacts flavor physics, highlighting the importance of family non-universal structures and their phenomenological implications.

Contribution

It introduces a consistent fermionic spectrum for little Higgs models that addresses flavor physics and anomaly cancellation, enhancing the model's realism and phenomenological viability.

Findings

Anomaly cancellation requires family non-universal fermion structures.

The completed fermionic spectrum influences flavor physics phenomenology.

Comparison with supersymmetry offers insights into model differences.

Abstract

We discuss the proper starting point to look into flavor physics under the perspective of solving the hierarchy problem with the little Higgs mechanism -- the construction of anomaly free fermionic spectra of the effective theory of extended electroweak gauge symmetry around the TeV scale. Anomaly cancellations among the three SM families, plus extra fermions, are typically needed, giving family non-universal flavor structures. Such a completed and consistent fermionic spectrum supplements a scalar sector little Higgs model, turning the latter into a realistic model the phenomenological viability of which can then be investigated. The implications for flavor physics are specially interesting. We give more elaborated discussion here on our basic perspective, trying to clarify on issues that are in our opinion under-appreciated. We also add a brief comment of little Higgs versus supersymmetry.