Ultra-weak sector, Higgs boson mass, and the dilaton

TL;DR

This paper explores a model where the Higgs boson mass is generated through a portal to a singlet field with a large VEV, involving ultra-weak couplings that are naturally small and resemble a pseudo-dilaton, with explicit scale invariance breaking via Coleman-Weinberg potential.

Contribution

It introduces a framework linking the Higgs mass to a singlet field with ultra-weak couplings, demonstrating natural smallness and scale invariance breaking mechanisms.

Findings

Ultra-weak couplings are naturally small due to shift symmetry.

The singlet field acts like a pseudo-dilaton.

Explicit scale invariance breaking is achieved via Coleman-Weinberg potential.

Abstract

The Higgs boson mass may arise from a portal coupling to a singlet field $\sigma$ which has a very large VEV $f \gg m_\text{Higgs}$. This requires a sector of "ultra-weak" couplings $\zeta_i$, where $\zeta_i \lesssim m_\text{Higgs}^2 / f^2$. Ultra-weak couplings are technically naturally small due to a custodial shift symmetry of $\sigma$ in the $\zeta_i \rightarrow 0$ limit. The singlet field $\sigma$ has properties similar to a pseudo-dilaton. We engineer explicit breaking of scale invariance in the ultra-weak sector via a Coleman-Weinberg potential, which requires hierarchies amongst the ultra-weak couplings.