  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.
