Testing the mechanism of lepton compositness

TL;DR

This paper investigates the Frohlich-Morchio-Strocchi mechanism explaining how leptons behave as elementary particles despite being bound states, using lattice gauge theory simulations.

Contribution

It provides the first lattice gauge theory test of the mechanism for fermions, specifically in a model with vectorial leptons that respects relevant symmetries.

Findings

Confirmed the Frohlich-Morchio-Strocchi mechanism for fermions.

Simulated a model with vectorial leptons obeying relevant symmetries.

Supported the idea that leptons can be viewed as bound states consistent with gauge invariance.

Abstract

Strict gauge invariance requires that physical left-handed leptons are actually bound states of the elementary left-handed lepton doublet and the Higgs field within the standard model. That they nonetheless behave almost like pure elementary particles is explained by the Fr\"ohlich-Morchio-Strocchi mechanism. Using lattice gauge theory, we test and confirm this mechanism for fermions. Though, due to the current inaccessibility of non-Abelian gauged Weyl fermions on the lattice, a model which contains vectorial leptons but which obeys all other relevant symmetries has been simulated.