QED Coupling from a 5-D Kaluza-Klein Theory

TL;DR

This paper demonstrates how the QED coupling can be derived from a five-dimensional Kaluza-Klein theory by applying a specific phase dependence and connection modification to a free spinor Lagrangian.

Contribution

It introduces a novel method to obtain QED coupling from a 5D spinor theory through Kaluza-Klein reduction with phase dependence and connection adjustments.

Findings

QED coupling emerges from 5D spinor theory

Phase dependence on extra coordinate is crucial

Modified connection yields correct 4D interaction

Abstract

We discuss the possibility to obtain, from a five-dimensional free spinor Lagrangian, the Quantum Electro-Dynamics (QED) coupling via a Kaluza-Klein reduction of the theory. This result is achieved taking a phase dependence of the spinor field on the extra-coordinate and modifying the corresponding connection. The five-dimensional spinor theory is covariant under the admissible coordinates transformations and its four-dimensional reduction provides the QED coupling term.