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arXiv · 2010.03125

Quantum parity conservation in planar quantum electrodynamics

O. M. Del Cima·D. H. T. Franco·L. S. Lima·E. S. Miranda
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Abstract

Quantum parity conservation is verified at all orders in perturbation theory for a massless parity-even $U(1)\times U(1)$ planar quantum electrodynamics (QED$_3$) model. The presence of two massless fermions requires the Lowenstein-Zimmermann (LZ) subtraction scheme, in the framework of the Bogoliubov-Parasiuk-Hepp-Zimmermann-Lowenstein (BPHZL) renormalization method, in order to subtract the infrared divergences induced by the ultraviolet subtractions at 1- and 2-loops, however thanks to the superrenormalizability of the model the ultraviolet divergences are bounded up to 2-loops. Finally, it is proved that the BPHZL renormalization method preserves parity for the model taken into consideration, contrary to what happens to the ordinary massless parity-even $U(1)$ QED$_3$.

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O. M. Del Cima, D. H. T. Franco, L. S. Lima, E. S. Miranda. 2020-10-07. Quantum parity conservation in planar quantum electrodynamics. https://doi.org/10.1007/s10773-021-04851-8

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