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arXiv · 1612.04177

Cosmology in nonlinear multidimensional gravity and the Casimir effect

S. V. Bolokhov·K. A. Bronnikov
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Abstract

We study the possible cosmological models in Kaluza-Klein-type multidimensional gravity with a curvature-nonlinear Lagrangian and a spherical extra space, taking into account the Casimir energy. First, we find a minimum of the effective potential of extra dimensions, leading to a physically reasonable value of the effective cosmological constant in our 4D space-time. In this model, the huge Casimir energy density is compensated by a fine-tuned contribution of the curvature-nonlinear terms in the original action. Second, we present a viable model with slowly evolving extra dimensions and power-law inflation in our space-time. In both models, the results formulated in Einstein and Jordan frames are compared.

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S. V. Bolokhov, K. A. Bronnikov. 2016-12-13. Cosmology in nonlinear multidimensional gravity and the Casimir effect. https://doi.org/10.1134/s0202289316040034

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