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Non-singular solutions in multidimensional model with scalar fields and exponential potential

J. -M. Alimi·V. D. Ivashchuk·V. N. Melnikov
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Abstract

Using developed earlier our methods for multidimensional models \cite{M1,M2,M3} a family of cosmological-type solutions in D-dimensional model with two sets of scalar fields \vecϕ and \vecψ and exponential potential depending upon \vecϕ is considered. The solutions are defined on a product of n Ricci-flat spaces. The fields from \vecϕ have positive kinetic terms and \vecψ are "phantom" fields with negative kinetic terms. For vector coupling constant obeying 0< \vecλ^2 < (D-1)/(D-2) a subclass of non-singular solutions is singled out. The solutions from this subclass are regular for all values of synchronous "time" τ\in (- \infty, + \infty). For \vecλ^2 < 1/(D-2) we get an asymptotically accelerated and isotropic expansion for large values of τ.

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J. -M. Alimi, V. D. Ivashchuk, V. N. Melnikov. 2005-07-05. Non-singular solutions in multidimensional model with scalar fields and exponential potential. https://arxiv.org/abs/gr-qc/0504044

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