Regularization of QED by a generalized ’t Hooft and Veltman method

Generalizing the ’t Hooft and Veltman method of unitary regulators, we demonstrate for the first time the existence of local, Lorentz-invariant, physically motivated Lagrangians of quantum-electrodynamic phenomena such that: (i) Feynman diagrams are finite and equal the diagrams of QED but with regularized propagators. (ii) N-point Green functions are causal. (iii) Smatrix relates only electrons, positrons and photons, is unitary and Lorentzinvariant, and conserves charge and total four-momentum.