Indeterminacy and Electron Spin


SINCE a dipole of magnetic moment M in a magnetic field of intensity H has a potential energy—M.H, two free electrons in magnetized iron with magnetic axes respectively parallel and anti-parallel to the direction of magnetization should differ in potential energy by Heh/2πmc, where H is the effective field intensity acting on a free electron in the iron. It may be of some interest to see whether this difference in energy could be detected in an ideal experiment, for example, by a splitting under magnetization of the photo-electric threshold of iron, or whether the quantum indeterminacy prevents the resolution, as Bohr has shown it must in a Stern-Gerlach experiment on a beam of free electrons1.

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  1. 1

    See Mott, N. F., Proc. Roy. Soc., A, 124, 425 (1929).

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COX, R., MYERS, F. Indeterminacy and Electron Spin. Nature 142, 394 (1938).

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