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arXiv · 1409.6867

Electromagnetism with dimension-five operators

Leonardo Campanelli
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Abstract

We derive, in curved spacetime, the most general Lorentz-violating electromagnetic Lagrangian containing dimension-five operators with one more derivative than the Maxwell term in the hypothesis that Lorentz symmetry is broken by a background four-vector $n_μ$. We then study, for the case of isotropic $n_μ$, the generation of cosmic magnetic fields at inflation and cosmic birefringence. In the limiting case of Minkowski spacetime, we find that other than the CPT-odd Myers-Pospelov term, there exists another CPT-odd term that gives rise to nontrivial dispersion and constitutive relations.

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Leonardo Campanelli. 2014-11-13. Electromagnetism with dimension-five operators. https://doi.org/10.1103/physrevd.90.105014

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