Softening Higgs Naturalness - an EFT Analysis

TL;DR

This paper uses effective field theory to analyze the conditions under which new heavy physics can address the Higgs naturalness problem, identifying operators and theories that achieve this without conflicting with experiments.

Contribution

It introduces the concept of EFT Naturalness, deriving conditions and operators for heavy physics to stabilize the Higgs mass, and classifies theories capable of generating these operators at tree-level.

Findings

Higher-dimensional operators can restore naturalness.

Heavy theories generating these operators are classified.

Experimental constraints on EFT Naturalness are discussed.

Abstract

We investigate naturalness in the Standard Model (SM) Higgs sector using effective field theory (EFT) techniques and find the requirements on the new heavy physics that can potentially cure the little hierarchy problem below a scale $\Lambda \gg O(1 ~{\rm TeV})$, assuming the new heavy particles have a mass larger than $ \Lambda $. In particular, we determine the conditions under which the 1-loop corrections to $ m_h $ from the heavy new physics can balance those created by SM loop effects up to the naturalness scale $\Lambda$, a condition we denote by "EFT Naturalness". We obtain the higher dimensional ($n \ge 5$) operators in the effective Lagrangian that can lead to EFT Naturalness, and classify the underlying heavy theories that can generate such operators at tree-level. We also address the experimental constraints on our EFT Naturalness setup and discuss the expected experimental signals of the new heavy physics associated with EFT Naturalness.