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

Marijan Ribaric·Luka Sustersic
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Abstract

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) S-matrix relates only electrons, positrons and photons, is unitary and Lorentz-invariant, and conserves charge and total four-momentum.

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Marijan Ribaric, Luka Sustersic. 2000-06-05. Regularization of QED by a generalized 't Hooft and Veltman method. https://arxiv.org/abs/hep-th/9909207

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