Accelerating Cosmologies in Lovelock Gravity with Dilaton

ABSTRACT

For the description of the Universe expansion, compatible with observational data, a model of Lovelock gravity with dilaton is investigated. D-dimensional space with 3- and (D-4)-dimensional maximally symmetric subspaces is considered. Space without matter and space with perfect fluid are under test. In various forms of the theory (third order without dilaton and second order with dilaton and without it) there are obtained stationary, power-law, exponential and exponent-of-exponent form cosmological solutions. Last two forms include solutions which are clear to describe accelerating expansion of 3-dimensional subspace. Also there is a set of solutions describing cosmological expansion which does not tend to isotropization in the presence of matter.

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