Geonium spectra·electron radius·cosmon

By means of a new, continuous version of the Stern-Gerlach effect the g-factor of the electron, an elementary particle as simple as a quark, has been measured to 4 parts in 1012. After QED corrections, this g-factor deviates from the Dirac value 2 by ∼10-10. A graph of corrected measured non-Dirac contributions |g-2| vs normalized radius for the three next larger stable charged near-Dirac fermions, proton, triton, and 3He nucleus, when applied to the electron, then suggests an rms radius R<10-20 cm. The graph further suggests a progression of ever smaller, heavier and less imperfect near-Dirac particles, until ''the'' elementary particle, the ''cosmon'' is reached. A lone ''cosmon/anticosmon'' pair, bound so tightly that its relativistic mass is zero, is assumed to have been formed from the metastable vacuum in a spontaneous quantum jump. Rapid disintegration of cosmon and anticosmon, each of immense mass, then formed the early universe in the big bang. No infinitely small point particles or singularities appear in our picture of a universe finite in the large and small