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arXiv · 0901.0025

Electric S-brane solutions corresponding to rank-2 Lie algebras: acceleration and small variation of G

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

Electric S-brane solutions with two non-composite electric branes and a set of l scalar fields are considered. The intersection rules for branes correspond to Lie algebras A_2, C_2 and G_2. The solutions contain five factor spaces. One of them, M_0, is interpreted as our 3-dimensional space. It is shown that there exists a time interval where accelerated expansion of our 3-dimensional space is compatible with a small enough variation of the effective gravitational constant G(τ). This interval contains τ_0, a point of minimum of the function G(τ). A special solution with two phantom scalar fields is analyzed and it is shown that in the vicinity of the point τ_0 the time variation of G(τ) (calculated in the linear approximation) decreases in the sequence of Lie algebras A_2, C_2 and G_2.

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V. D. Ivashchuk, S. A. Kononogov, V. N. Melnikov. 2008-12-30. Electric S-brane solutions corresponding to rank-2 Lie algebras: acceleration and small variation of G. https://doi.org/10.1134/s0202289308030055

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