# Fermion stabilisation of extra dimensions and natural mass hierarchies

## TL;DR

This paper demonstrates that fermion-induced Casimir forces in extra-dimensional models can naturally stabilize the geometry and generate large electroweak hierarchies without fine tuning, linking fermion mass hierarchies to extra-dimensional stabilization.

## Contribution

It shows that fermion Casimir forces can stabilize Randall-Sundrum models and produce large hierarchies naturally, connecting fermion mass generation mechanisms with extra-dimensional stabilization.

## Key findings

- Casimir forces from fermions can stabilize extra dimensions.
- Large electroweak hierarchies can emerge without fine tuning.
- The model applies to both Higgs and Higgsless symmetry breaking mechanisms.

## Abstract

Casimir forces from fermions in an extra dimension can stabilise Randall-Sundrum models. Contrary to previous expectations, the stabilisation can produce large electroweak hierarchies without fine tuning. The Casimir stabilisation occurs in the same five-dimensional fermion models which have been found to give the observed fermion mass hierarchies. This is shown for masses generated by the Higgs mechanism and by a Higgsless symmetry breaking mechanism, where new light Kaluza-Klein states are presented