Fundamental partial compositeness

TL;DR

This paper develops renormalizable extensions of the Standard Model that produce a composite Higgs via a new strong force, incorporating partial compositeness, custodial symmetry, and natural flavor structures, valid up to the Planck scale.

Contribution

It introduces a novel class of renormalizable models with strong dynamics and scalars that realize partial compositeness and custodial symmetry, extending previous composite Higgs frameworks.

Findings

Successful models exist under certain scalar dynamics assumptions.

Standard Model fermions gain mass at tree level.

Baryon and lepton numbers are accidental symmetries.

Abstract

We construct renormalizable Standard Model extensions, valid up to the Planck scale, that give a composite Higgs from a new fundamental strong force acting on fermions and scalars. Yukawa interactions of these particles with Standard Model fermions realize the partial compositeness scenario. Under certain assumptions on the dynamics of the scalars, successful models exist because gauge quantum numbers of Standard Model fermions admit a minimal enough 'square root'. Furthermore, right-handed SM fermions have an SU(2)$_R$-like structure, yielding a custodially-protected composite Higgs. Baryon and lepton numbers arise accidentally. Standard Model fermions acquire mass at tree level, while the Higgs potential and flavor violations are generated by quantum corrections. We further discuss accidental symmetries and other dynamical features stemming from the new strongly interacting scalars. If the same phenomenology can be obtained from models without our elementary scalars, they would reappear as composite states.