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arXiv · 2305.19171

Perturbations in Horndeski theory above anisotropic cosmological background

S. Mironov·A. Shtennikova
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Abstract

Considering an anisotropic cosmological background is an interesting and simultaneously challenging problem of theoretical physics, since we not only assume a high degree of anisotropy in the early stages of the Universe, but also observe it to a small degree until now. In this paper we have constructed the unconstrained action for the perturbations above Bianchi I type background in the most general scalar-tensor theory of gravity, the Horndeski theory, and evaluate the effect of the deviation from the anisotropic background on the previously established stable solution obtained in previous works.

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S. Mironov, A. Shtennikova. 2023-05-30. Perturbations in Horndeski theory above anisotropic cosmological background. https://doi.org/10.1134/s002136402360204x

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