  A classical circularly polarized electromagnetic wave carries angular
momentum, and represents the classical limit of a photon, which carries
quantized spin. It is shown that a very similar picture of a circularly
polarized coherent wave can account for both the spin of an electron and its
quantum wave function, in a Lorentz-invariant fashion. The photon-electron
interaction occurs through the usual electromagnetic potentials, modulating the
frequency and wavevector (energy and momentum) of this rotating spin field.
Other quantum particles can also be represented either as rotating spin fields,
or as composites of such fields. Taken together, this picture suggests an
alternative interpretation of quantum mechanics based solely on coherent wave
packets, with no point particles present.
