Asymptotic properties of the electron-proton scattering amplitude and sum rules for the Schwinger term

The relationship is established between the asymptotic behavior of the electron-proton scattering amplitude, the Jost–Lehmann–Dyson spectral function of the current commutator, and the sum rules for the Schwinger term. It is shown that the conditions on the Jost–Lehmann– Dyson spectral function are less stringent than those that lead to the “scaling invarianee” property of the scattering amplitude.