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The structure of radiatively induced Lorentz and CPT violation in QED at finite temperature

L. Cervi·L. Griguolo·D. Seminara
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Abstract

We obtain the induced Lorentz- and CPT-violating term in QED at finite temperature using imaginary-time formalism and dimensional regularization. Its form resembles a Chern-Simons-like structure, but, unexpectedly, it does not depend on the temporal component of the fixed $b_μ$ constant vector that is coupled to the axial current. Nevertheless Ward identities are respected and its coefficient vanishes at T=0, consistently with previous computations with the same regularization procedure, and it is a non-trivial function of temperature. We argue that at finite $T$ a Chern-Simons-like Lorentz- and CPT-violating term is generically present, the value of its coefficient being unambiguously determined up to a $T-$independent constant, related to the zero-temperature renormalization conditions.

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L. Cervi, L. Griguolo, D. Seminara. 2001-04-03. The structure of radiatively induced Lorentz and CPT violation in QED at finite temperature. https://doi.org/10.1103/physrevd.64.105003

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