Flavor hierarchies from dynamical scales

TL;DR

This paper explores how dynamically generating fermion Yukawa couplings at different scales in composite Higgs models can address flavor hierarchies and CP violation constraints, predicting observable deviations in flavor physics.

Contribution

It introduces a framework where fermion Yukawa couplings are generated at different scales, linking lighter fermions to higher scales, and shows this can satisfy flavor constraints without extra symmetries.

Findings

Flavor and CP constraints are satisfied at a few TeV scale.

Predicted deviations in B physics observables could be observed in future experiments.

Top-mediated contributions dominate B physics deviations.

Abstract

One main obstacle for any beyond the SM (BSM) scenario solving the hierarchy problem is its potentially large contributions to electric dipole moments. An elegant way to avoid this problem is to have the light SM fermions couple to the BSM sector only through bilinears, $\bar ff$. This possibility can be neatly implemented in composite Higgs models. We study the implications of dynamically generating the fermion Yukawa couplings at different scales, relating larger scales to lighter SM fermions. We show that all flavor and CP-violating constraints can be easily accommodated for a BSM scale of few TeV, without requiring any extra symmetry. Contributions to B physics are mainly mediated by the top, giving a predictive pattern of deviations in $\Delta F=2$ and $\Delta F=1$ flavor observables that could be seen in future experiments.