Commuting Co-Ordinates in the New Field Theory

M. H. L. Pryce
1935 Proceedings of the Royal Society A  
parts of the commuting co-ordinates used by Dirac do not commute, but satisfy together with the momenta and the total angular momenta the same commutation rules as the co-ordinates, momenta and angular momenta of the electromagnetic theory. The electromagnetic inner angular momentum plays an analogous role to that of Dirac's spin; but it has a real physical meaning and is not restricted to the eigenvalues ±
doi:10.1098/rspa.1935.0094 fatcat:kpyistjwdnai3h3wqzpwcy7wfu