How Electrons Spin

TL;DR

This paper explores the classical interpretation of electron spin, showing that the electron's charge and mass distribution can explain its magnetic properties without requiring superluminal rotation.

Contribution

It demonstrates that the electron's spin can be understood through the Dirac field's charge and mass flow, avoiding superluminal speeds and explaining the gyromagnetic ratio.

Findings

Electron's charge and mass are spread over large distances.

Superluminal velocities are avoided in the classical model.

Electron's gyromagnetic ratio is explained by charge rotating faster than mass.

Abstract

There are a number of reasons to think that the electron cannot truly be spinning. Given how small the electron is generally taken to be, it would have to rotate superluminally to have the right angular momentum and magnetic moment. Also, the electron's gyromagnetic ratio is twice the value one would expect for an ordinary classical rotating charged body. These obstacles can be overcome by examining the flow of mass and charge in the Dirac field (interpreted as giving the classical state of the electron). Superluminal velocities are avoided because the electron's mass and charge are spread over sufficiently large distances that neither the velocity of mass flow nor the velocity of charge flow need to exceed the speed of light. The electron's gyromagnetic ratio is twice the expected value because its charge rotates twice as fast as its mass.