Nucleon Form-Factor Sum Rules from the Nonforward Retarded Commutator

Abstract

Using the equal-time commutators for current densities at equal times, five sum rules involving the nucleon from factors are derived by considering the Fourier transform of the retarded commutator of the currents evaluated between nucleon states of nonequal momenta. This leads to sum rules that contain not only the masses of the external vector particles, but also the momentum transfers, which give new sum rules and generalize previous sum rules.