Dynamical electroweak symmetry breaking due to strong Yukawa interactions

TL;DR

This paper proposes a novel mechanism for electroweak symmetry breaking driven by strong Yukawa interactions, allowing fermion and gauge boson mass generation without scalar vacuum expectation values.

Contribution

It introduces a model where EWSB occurs dynamically through strong Yukawa couplings, independent of scalar VEVs, with explicit mass and scalar splittings derived from self-energies.

Findings

EWSB achieved without scalar VEVs

Fermion and gauge boson masses derived from self-energies

Model compatible with experimental constraints

Abstract

We present a new mechanism for electroweak symmetry breaking (EWSB) based on a strong Yukawa dynamics. We consider an SU(2)_L x U(1)_Y gauge invariant model endowed with the usual Standard model fermion multiplets and with two massive scalar doublets. We show that, unlike in the Standard model, EWSB is possible even with vanishing vacuum expectation values of the scalars. Such EWSB is achieved dynamically by means of the (presumably strong) Yukawa couplings and manifests itself by the emergence of fermion and gauge boson masses and scalar mass-splittings, which are expressed in a closed form in terms of the fermion and scalar proper self-energies. The `would-be' Nambu--Goldstone bosons are shown to be composites of both the fermions and the scalars. We demonstrate that the simplest version of the model is compatible with basic experimental constraints.