Naturally Speaking: The Naturalness Criterion and Physics at the LHC

TL;DR

Giudice analyzes the naturalness problem of the Higgs mass within the LHC context, framing it as a test of whether a small parameter can be natural under 't Hooft's symmetry criterion and within effective field theory. The work traces historical developments, formalizes numerical naturalness, and surveys proposed resolutions from SUSY and Split SUSY to multiverse ideas, while offering a quantitative tuning measure. It argues that TeV-scale new physics is expected if naturalness holds, but that anthropic or criticality viewpoints could explain the hierarchy without new EFT particles. The practical impact is that LHC data will either confirm naturalness-based expectations or compel a radical rethinking of how fundamental scales are connected.

Abstract

A non-technical discussion of the naturalness criterion and its implications for new physics searches at the LHC. To be published in the book "LHC Perspectives", edited by G. Kane and A. Pierce.