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In the paper What is spin?, Am. J. Phys. 54 (1986) 500, by Hans C. Ohanian, spin is described as a circulating flow of energy in the wave-field of a particle. Is this the generally agreed upon explanation of intrinsic angular momentum or just a fringe theory?

(A similar thread exists on Reddit, but I couldn't find a satisfactory discussion there.)

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    $\begingroup$ I must admit this is very weird, for me. When I studied this subject I was taugh that spin (and helicity) is just a degree of freedom that appeared in quantising a particular irreducible representation of the Lorentz group. That's a very good question. $\endgroup$ – QuantumBrick Oct 9 '16 at 18:58
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    $\begingroup$ I've never heard anyone criticize the paper for incorrectness, but it also only appears as a footnote. None of my texts or instructors spent any time on it. I've never dug in to try to figure our why that should be, but the response feels like people find the result to be difficult to generalize or it is more complicated without making new predictions. It could be perfectly correct, but more difficult than is justified by the value it offers and it would get a response like that. But that is social guess work based on people knowing it is there and not bothering with it. $\endgroup$ – dmckee --- ex-moderator kitten Oct 9 '16 at 23:34
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Ohanian's paper shows that spin can be understood as a circulating flow of energy, and is a wave property, valid in both classical and quantum mechanical formulations, rather than inherently and mysteriously "quantum mechanical" in nature. A fine point not needed for calculations that can be ignored by the pragmatic experimental physicist. But to me (and apparently the author) it's comforting to have physical intuition so lacking in much of conventional qm.

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I read the abstract.

The basic reason it is not referred to or used is that main stream physics has elementary particles as point particles in the standard model and any wave nature attributed to the particle is on the probability distribution of its location in space and time.

it can be shown that the spin may be regarded as an angular momentum generated by a circulating flow of energy in the wave field of the electron.

A point particle can have no circulating flow of energy. So it may be a correct mathematically description but not within the language/model of mainstream particle physics at present.

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