A Composite Theory of Higgs and Flavour

TL;DR

This paper proposes a composite Higgs model with a flavor-deconstructed gauge group embedded in the strong sector, naturally addressing Higgs and flavor hierarchies while suppressing flavor violation and electric dipole moments.

Contribution

It introduces a novel composite Higgs framework featuring a second Higgs doublet and a flavor structure that reduces tuning and flavor constraints.

Findings

The model predicts a second Higgs doublet coupled to light generations.

Flavor violating effects are CKM- and chirally suppressed.

Electric dipole moments are naturally evaded due to mass alignment.

Abstract

We introduce a composite Higgs model in which a flavour deconstructed gauge group is embedded in the strong sector. The pattern of global symmetry breaking yields, as pseudo-Nambu-Goldstone (pNGB) bosons, both a Standard Model (SM)-like Higgs and the link field whose vacuum expectation value breaks the flavour non-universal gauge group down to the SM. Inevitably, a third pNGB appears, transforming as a second Higgs doublet coupled only to the light generations. This heavy Higgs naturally mediates suppressed light Yukawa couplings, providing a solution to the flavour puzzle. At the same time, new physics contributions to flavour violating observables are CKM- and chirally suppressed, while electric dipole moment bounds are evaded through an automatic mass alignment in the light fermion sector. The result is a natural framework for addressing the origin of both Higgs and flavour hierarchies, with reduced Higgs mass tuning and minimised impact in flavour observables, that is best tested by high-$p_T$ and precision electroweak measurements.