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arXiv · 1610.07951

Comment on "Fermion production in a magnetic field in a de Sitter universe"

Nistor Nicolaevici·Attila Farkas
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Abstract

We point out that the transition probabilities used in a recent perturbative calculation of pair creation in an external magnetic field in the expanding de Sitter space with the $in$ and $out$ fermion states defined by the Bunch-Davies modes [C. Crucean et al., Phys. Rev. D 73 044019 (20016)] are gauge dependent quantities. We examine the gauge variations of these amplitudes assuming a decoupling of the interaction at infinite times, which allows to conclude that the source of the problem lies in the nonoscillatory behavior of the fermion current in the infinite future.

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Nistor Nicolaevici, Attila Farkas. 2016-10-25. Comment on "Fermion production in a magnetic field in a de Sitter universe". https://doi.org/10.1103/physrevd.95.048501

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