Canonical Angular Momentum of Electron, Positron and the Gamma Photon

Abstract

We calculate the canonical angular momentum of a free electron, positron and gamma photon. We show that for any particle with charge q the canonical angular momentum ( J c ) is written as the summation of the kinetic angular momentum ( J kin ) and the intrinsic quantum flux dependent terms. In terms of the z-components this can be written as . For a free electron ( e - ) and a positron ( e + ) depending on the spin orientation we find that: ; ; and respectively. Similarly for a gamma ( γ ) photon, propagating in z direction with an angular frequency ω, the canonical angular momentum is found to be: , here the (+) and (-) signs stand for the right and left hand circular helicity respectively.