The magnetic moment of a particle of nonzero spin $S$ is computed by the introduction of minimal coupling into the appropriate Galilean-invariant wave equation. It is shown that the requirement that the differential equations be of first order, together with a minimality assumption on the number of components, uniquely implies a $g$ factor of $\frac{1}{S}$ . The role played by this minimality condition is made explicit by means of a counterexample.The magnetic moment of a particle of nonzero spin $S$ is computed by the introduction of minimal coupling into the appropriate Galilean-invariant wave equation. It is shown that the requirement that the differential equations be of first order, together with a minimality assumption on the number of components, uniquely implies a $g$ factor of $\frac{1}{S}$. The role played by this minimality condition is made explicit by means of a counterexample.

Physical Review LettersJun 15, 197063 citations

The Aharonov-Casher Effect for Particles of Arbitrary Spin

Ya. I. Azimov, R.M. Ryndin

The Aharonov-Casher (AC) effect for quantum motion of a neutral magnetized particle in the electric field is believed to be a topological effect closely related to the known Aharonov-Bohm (AB) effect. We study how it depends on the spin of the particle involved. Duality of the AB and AC effects is demonstrated to exist only for two extreme spin (and magnetic moment) projections. Classical consideration confirms the conclusion. Motion of a classical magnetized particle with generally oriented magnetic moment in the AC field appears to be subjected to both forces and torques. Only for two special orientations of the magnetic moment (same as in the quantum case) the motion is effectively free and similar to the AB motion of a charged particle. Thus, the AC effect is not really topological. Presence of higher multipoles totally destroys the possible AB-AC duality.The Aharonov-Casher (AC) effect for quantum motion of a neutral magnetized particle in the electric field is believed to be a topological effect closely related to the known Aharonov-Bohm (AB) effect. We study how it depends on the spin of the particle involved. Duality of the AB and AC effects is demonstrated to exist only for two extreme spin (and magnetic moment) projections. Classical consideration confirms the conclusion. Motion of a classical magnetized particle with generally oriented magnetic moment in the AC field appears to be subjected to both forces and torques. Only for two special orientations of the magnetic moment (same as in the quantum case) the motion is effectively free and similar to the AB motion of a charged particle. Thus, the AC effect is not really topological. Presence of higher multipoles totally destroys the possible AB-AC duality.

arXiv:hep-ph/9710433Physics of Atomic NucleiOct 22, 19971 citation

Spin of Atomic Particles

Robert D. Potter

ScienceDec 16, 19380 citations

The magnetic moment of a particle of nonzero spin

S

is computed by the introduction of minimal coupling into the appropriate Galilean-invariant wave equation. It is shown that the requirement that the differential equations be of first order, together with a minimality assumption on the number of components, uniquely implies a

g

factor of

\frac{1}{S}

. The role played by this minimality condition is made explicit by means of a counterexample.