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arXiv · hep-th/0612264

Non-singular solutions in multidimensional cosmology with a perfect fluid: acceleration and variation of G

V. D. Ivashchuk·S. A. Kononogov·V. N. Melnikov·M. Novello
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Abstract

Exact solutions with an exponential behaviour of the scale factors are considered in a multidimensional cosmological model describing the dynamics of n+1 Ricci-flat factor spaces M_i in the presence of a one-component perfect fluid. The pressures in all spaces are proportional to the density: p_i = w_i ρ, i = 0,...,n. Solutions with accelerated expansion of our 3-space M_0 and a small enough variation of the gravitational constant G are found. These solutions exist for two branches of the parameter w_0. The first branch describes superstiff matter with w_0 > 1, the second one may contain phantom matter with w_0 < - 1.

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V. D. Ivashchuk, S. A. Kononogov, V. N. Melnikov, M. Novello. 2008-03-09. Non-singular solutions in multidimensional cosmology with a perfect fluid: acceleration and variation of G. https://arxiv.org/abs/hep-th/0612264

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