Vacuum stability, neutrinos, and dark matter

TL;DR

This paper investigates how extensions of the Standard Model with neutrinos and dark matter can influence vacuum stability, highlighting the roles of new particles and couplings in maintaining a stable Higgs potential up to high energy scales.

Contribution

It analyzes the impact of neutrino and dark matter sectors on Higgs vacuum stability using minimal SM extensions and RG evolution, identifying key factors that stabilize the vacuum.

Findings

Darkon scalar stabilizes the vacuum up to high scales.

Heavy neutrino Yukawa couplings affect the instability scale.

MDM and fermion triplet contribute positively to gauge coupling RG.

Abstract

Motivated by the discovery hint of the Standard Model (SM) Higgs mass around 125 GeV at the LHC, we study the vacuum stability and perturbativity bounds on Higgs scalar of the SM extensions including neutrinos and dark matter (DM). Guided by the SM gauge symmetry and the minimal changes in the SM Higgs potential we consider two extensions of neutrino sector (Type-I and Type-III seesaw mechanisms) and DM sector (a real scalar singlet (darkon) and minimal dark matter (MDM)) respectively. The darkon contributes positively to the $\beta$ function of the Higgs quartic coupling $\lambda$ and can stabilize the SM vacuum up to high scale. Similar to the top quark in the SM we find the cause of instability is sensitive to the size of new Yukawa couplings between heavy neutrinos and Higgs boson, namely, the scale of seesaw mechanism. MDM and Type-III seesaw fermion triplet, two nontrivial representations of $SU(2)_{L}$ group, will bring the additional positive contributions to the gauge coupling $g_{2}$ renormalization group (RG) evolution and would also help to stabilize the electroweak vacuum up to high scale.