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arXiv · 2111.13165

Bianchi type I cosmology with a Kalb-Ramond background field

R. V. Maluf·Juliano C. S. Neves
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Abstract

An effect of the Lorentz symmetry breaking is pointed out in the cosmological context. Using a Bianchi I geometry coupled to the Kalb-Ramond field, a consequence of the Lorentz symmetry violation is indicated by a different rate of expansion in a given spatial direction. This article focuses on the coupling constant $ξ_1$, which generates, from the Kalb-Ramond field, all three coefficients that give rise to the Lorentz violation in the gravity sector of the minimal Standard Model Extension. The coupling constant $ξ_1$ increases the rate of expansion of the universe in a given direction during a dark energy era. As a consequence, a range of validity of that coupling constant is also obtained.

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R. V. Maluf, Juliano C. S. Neves. 2022-02-14. Bianchi type I cosmology with a Kalb-Ramond background field. https://doi.org/10.1140/epjc%2Fs10052-022-10109-2

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