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arXiv · 1804.08413

On quantum aspects of the higher-derivative Lorentz-breaking extension of QED

T. Mariz·J. R. Nascimento·A. Yu. Petrov·C. Marat Reyes
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Abstract

We consider the higher-derivative Lorentz-breaking extension of QED, where the new terms are the Myers-Pospelov-like ones in gauge and spinor sectors, and the higher--derivative CFJ term. For this theory, we study its tree-level dynamics, discuss the dispersion relation, and present one more scheme for its perturbative generation, including the finite temperature case. Also, we develop a method to study perturbative unitarity based on consistent rotation of the theory to Euclidean space. We use this method to verify explicitly that for special choices of the Lorentz-breaking vector, the unitarity is preserved at the one-loop level, even in the presence of higher time derivatives.

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T. Mariz, J. R. Nascimento, A. Yu. Petrov, C. Marat Reyes. 2018-04-23. On quantum aspects of the higher-derivative Lorentz-breaking extension of QED. https://doi.org/10.1103/physrevd.99.096012

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