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arXiv · 1710.08753

Anisotropic cosmological solutions in $R + R^2$ gravity

Daniel Müller·Angelo Ricciardone·Alexei A. Starobinsky·Aleksey Toporensky
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Abstract

In this paper we investigate the past evolution of an anisotropic Bianchi I universe in $R+R^2$ gravity. Using the dynamical system approach we show that there exists a new two-parameters set of solutions that includes both an isotropic "false radiation" solution and an anisotropic generalized Kasner solution, which is stable. We derive the analytic behaviour of the shear from a specific property of $f(R)$ gravity and the analytic asymptotic form of the Ricci scalar when approaching the initial singularity. Finally we numerically checked our results.

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Daniel Müller, Angelo Ricciardone, Alexei A. Starobinsky, Aleksey Toporensky. 2017-10-24. Anisotropic cosmological solutions in $R + R^2$ gravity. https://doi.org/10.1140/epjc%2Fs10052-018-5778-0

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