Effects of Curvature-Higgs Coupling on Electroweak Fine-Tuning

TL;DR

This paper proposes a fine-tuning mechanism involving the nonminimal coupling of the Higgs field to spacetime curvature, which stabilizes the electroweak scale against ultraviolet divergences without altering the Standard Model's loop structure.

Contribution

It introduces a novel fine-tuning scheme using curvature-Higgs coupling to stabilize the electroweak scale, applicable even in extended models with additional scalars.

Findings

Nonminimal curvature-Higgs coupling can stabilize the electroweak scale.

The scheme works with classical gravity and does not affect SM loop structure.

Applicable to models with extra Higgs or singlet scalar fields.

Abstract

It is shown that, nonminimal coupling between the Standard Model (SM) Higgs field and spacetime curvature, present already at the renormalizable level, can be fine-tuned to stabilize the electroweak scale against power-law ultraviolet divergences. The nonminimal coupling acts as an extrinsic stabilizer with no effect on the loop structure of the SM, if gravity is classical. This novel fine-tuning scheme, which could also be interpreted within Sakharov's induced gravity approach, works neatly in extensions of the SM involving additional Higgs fields or singlet scalars.