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Exact calculation of the radiatively-induced Lorentz and CPT violation in QED

M. Perez-Victoria
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Abstract

Radiative corrections arising from the axial coupling of charged fermions to a constant vector b_μcan induce a Lorentz- and CPT-violating Chern-Simons term in the QED action. We calculate the exact one-loop correction to this term keeping the full b_μdependence, and show that in the physically interesting cases it coincides with the lowest-order result. The effect of regularization and renormalization and the implications of the result are briefly discussed.

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M. Perez-Victoria. 2001-02-22. Exact calculation of the radiatively-induced Lorentz and CPT violation in QED. https://doi.org/10.1103/physrevlett.83.2518

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