Torsional regularization of vertex function

The noncommutativity of the momentum components, arising from spacetime torsion coupled to spin, replaces the integration over the momentum in loop Feynman diagrams with the summation over the momentum eigenvalues. This prescription regularizes logarithmically divergent integrals by turning them into convergent sums. We apply torsional regularization to the vertex function in quantum electrodynamics in the one-loop correction. The magnetic form factor is consistent with Schwinger's value for the anomalous magnetic dipole moment of a fermion. We show that it depends on the mass of a fermion, which may explain the observed deviation of the magnetic moment of a muon from the predicted theoretical value. We also show that the electric form factor is ultraviolet convergent.