Vacuum stability with radiative Yukawa couplings

TL;DR

This paper investigates how radiative Yukawa couplings from a dark sector can stabilize the electroweak vacuum, offering a novel mechanism that avoids fine-tuning and predicts new testable particles at colliders.

Contribution

It introduces a new framework where Yukawa couplings are radiatively generated, leading to vacuum stability without fine-tuning, and explores potential collider signatures.

Findings

Vacuum stability achieved without parameter tuning.

Yukawa couplings generated radiatively from dark sector.

Testable predictions for collider experiments.

Abstract

We explore the electroweak vacuum stability in the framework of a recently proposed paradigm for the origin of Yukawa couplings. These arise as low energy effective couplings radiatively generated by portal interactions with a hidden, or dark, sector at the one-loop level. Possible tree-level Yukawa couplings are forbidden by a new underlying symmetry, assumed to be spontaneously broken by the vacuum expectation value of a new scalar field above the electroweak scale. As a consequence, the top Yukawa interaction ceases to behave as a local operator at energies above the new sector scale and, therefore, cannot contribute to the running of the quartic Higgs coupling at higher energies. By studying two complementary scenarios, we explicitly show that the framework can achieve the stability of the electroweak vacuum without particular tuning of parameters. The proposed mechanism requires the existence of a dark sector and new portal messenger scalar interactions that, connecting the Standard Model to the dark sector fields, could be tested at the LHC and future collider experiments.