On a Relativistic Magnetic Top
Keywords: relativistic magnetic top, particle spin, point electron
The development of theories of elementary particles as extended objects, from Thomson to Dehmelt and MacGregor, is reviewed. Most of the theories are inspired by the existence of particle spin. The arguments of their authors are contrasted to Pauli's assertion than spin is "a classically non-explainable two-valuedness," as well as to Dirac's theory of a point electron.