Is the electron magnetic moment unique?

TL;DR

This paper investigates the electron's magnetic moment using two different methods and finds that it varies with the electron's state in hydrogen-like ions, suggesting the electron is not point-like and can be deformed.

Contribution

It demonstrates that the electron's magnetic moment is state-dependent and differs between methods, challenging the notion of the electron as a point particle.

Findings

Electron magnetic moment varies with electron state in ions.

Different methods yield different magnetic moment values.

Electron exhibits deformability under external fields.

Abstract

There exist two methods for finding the magnetic moment of the electron. In the first of them employed in quantum electrodynamics, one calculates the energy of the electron placed in a constant magnetic field, the extra energy due to the field being proportional to the magnetic moment. It is also possible to use the second method proceeding from the fact that the asymptotic form of the vector potential at infinity is proportional to the magnetic moment. If the electron were point-like, both the methods would yield identical results. In the present paper is studied the magnetic field created by the electron in hydrogen-like ions, which enables one to find the electron magnetic moment by the second method. The electron magnetic moment in this case proves to be different in different states of the electron in the Coulomb field of the ions and, moreover, is distinct from the magnetic moment calculated by the first method. The results of the paper show that the electron is not small and is deformable under action of external fields.