Some Effects of the Intrinsic Magnetic Moment of the Electron

Effects of the magnetic moment of the electron of the six-vector type are calculated. According to the hypothesis followed here, the electron's behavior in the field of a nucleus is described only approximately as that of a point charge. More accurately, it behaves as a particle having mainly the properties of a point charge which are corrected by the addition of a small "intrinsic" magnetic moment. In the present note the purely empirical point of view of an intrinsic magnetic moment is followed without any attempt at a justification from the point of view of quantum electrodynamics which has been given by Schwinger. Formulas are worked out for the effect on hyperfine structure, on the Landé $g$ factor and the contribution to the Lamb-Retherford line shift. The arrangement of the calculations is such as to have the same system for the ordinary hyperfine structure and the other effects. The finite rather than zero size of the nuclear current system is explicitly included in the formulas.