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arXiv · 1503.00860

On exponential cosmological type solutions in the model with Gauss-Bonnet term and variation of gravitational constant

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

A D-dimensional gravitational model with Gauss-Bonnet term is considered. When ansatz with diagonal cosmological type metrics is adopted, we find solutions with exponential dependence of scale factors (with respect to "synchronous-like" variable) which describe an exponential expansion of "our" 3-dimensional factor-space and obey the observational constraints on the temporal variation of effective gravitational constant G. Among them there are two exact solutions in dimensions D = 22, 28 with constant G and also an infinite series of solutions in dimensions D \ge 2690 with the variation of G obeying the observational data.

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V. D. Ivashchuk, A. A. Kobtsev. 2016-10-02. On exponential cosmological type solutions in the model with Gauss-Bonnet term and variation of gravitational constant. https://doi.org/10.1140/epjc%2Fs10052-015-3394-9

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