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arXiv · 2009.10204

On stable exponential cosmological solutions with two factor spaces in $(1+ m + 2)$-dimensional EGB model with $\Lambda$-term

V. D. Ivashchuk·A. A. Kobtsev
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Abstract

A $(m+ 3)$-dimensional Einstein-Gauss-Bonnet gravitational model including the Gauss-Bonnet term and the cosmological term $\Lambda$ is considered. Exact solutions with exponential time dependence of two scale factors, governed by two Hubble-like parameters $H >0$ and $h \neq H$, corresponding to factor spaces of dimensions $m >2$ and $l = 2$, respectively, are found. Under certain restrictions on $x = h/H $, the stability of the solutions in a class of cosmological solutions with diagonal metrics is proved. A subclass of solutions with small enough variation of the effective gravitational constant $G$ is considered and the stability of all solutions from this subclass is shown.

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V. D. Ivashchuk, A. A. Kobtsev. 2020-09-21. On stable exponential cosmological solutions with two factor spaces in $(1+ m + 2)$-dimensional EGB model with $\Lambda$-term. https://arxiv.org/abs/2009.10204

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