A solution to the hierarchy problem from an almost decoupled hidden sector within a classically scale invariant theory

TL;DR

This paper proposes a classically scale invariant model with a hidden sector where the hierarchy between the weak and Planck scales naturally emerges as a quantum effect, avoiding the hierarchy problem.

Contribution

It introduces a simple scale invariant theory with a nearly decoupled hidden sector that explains the hierarchy without fine-tuning.

Findings

Hierarchy emerges in the decoupling limit

Quadratic divergences are avoided due to scale invariance

The model provides a natural explanation for the weak/Planck scale separation

Abstract

If scale invariance is a classical symmetry then both the Planck scale and the weak scale should emerge as quantum effects. We show that this can be realized in simple scale invariant theories with a hidden sector. The weak/Planck scale hierarchy emerges in the (technically natural) limit where the hidden sector decouples from the ordinary sector. The weak scale is protected from quadratic divergences because of classical scale invariance, so there is no hierarchy problem.