The subject is a Letter to the Editor by H. Aspden in American Journal of Physics, v. 53, p. 938 (1985).
Commentary: This letter refers to the editorial entitled 'Small things in physics can be big things' . It begins by commenting that "Surely, the proton is predictable," and, after showing how minor discrepancies have led to major advances in theoretical physics, ends with the challenging reminder that, even after 50 years, there is still no resolution of what is a major discrepancy involving the proton magnetic moment. It is discrepant by a factor of almost 2.79285, with this its value measured in nuclear magnetons. Having recently  responded to Victor F. Weisskopf's concern about the proton-electron mass ratio, by drawing attention to a 1975 theoretical derivation of this quantity, now valid at the one part in 10 million level of its precision measurement, I offer also a comment in response to the challenge of Ref. 1.
I believe that the proton magnetic moment and, indeed, the neutron magnetic moment are explicable fully by a theory involving a standing wave system cantered on the proton and its quantum electrodynamic interaction with virtual muons and electrons in the surrounding field. The method is too long to outline in this short letter, but it is hoped that my papers on the subject will be published in the scientific literature in the not-too-distant future. Meanwhile, readers can share my own fascination with a quite remarkable result, which, if fortuitous, would be a cruel act on the part of nature. The theory gives reason for believing, first, that the basic proton magnetic moment is governed normally by the usual g factor of 2, but that standing wave excitation increases this to its anomalous value of nearly 2.79285. Second, the neutron responds to a wave excitation between virtual muons and electrons in the magnetic field as if separated from a neutralizing charge to become a non-excited (g = 2) antiproton for 22/23 parts of any short period of time. The standing wave resonance indicates integer relationships; it is relevant that the nearest integer 207 to the muon-electron mass ratio includes, as its highest prime factor, the integer 23. The consequence is that the neutron magnetic moment should then be (2)(l-1/23) or 44/23 nuclear magnetons attributable to a negative charge. Evaluated, this gives a theoretical neutron magnetic moment of -1.913043478 nuclear magnetons, in excellent accord with the measured value of -1.91304308(54)(0.28 ppm) reported by Greene et al. . If this standing wave explanation eventually finds acceptance, the theme of the editorial will still hold, because it was the explanation of a small discrepancy connected with the electron magnetic moment that suggested the standing wave approach to the proton and neutron.
 J. S. Rigden, Am. J. Phys., 53, 107 (1985).
 H. Aspden, Physics Today 37, 15 (1984).
 G. L Greene, N. F. Ramsey, W. Mampe, J. M. Pendlebury, K. Smith, W. B. Dress, P. D. Miller, and P. Perrin, Precision Measurement and Fundamental Constants, edited by B. N. Taylor and W. D. Phillips (Natl. Bur. Stand., Spec. Publ. 617, 1984).