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arXiv · 1803.01887

Realistic Compactification Models in Einstein-Gauss-Bonnet Gravity

Sergey Pavluchenko
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Abstract

We report the results of a study on the dynamical compactification of spatially flat cosmological models in Einstein-Gauss-Bonnet gravity. The analysis was performed in the arbitrary dimension in order to be more general. We consider both vacuum and $\Lambda$-term cases. Our results suggest that for vacuum case, realistic compactification into the Kasner (power law) regime occurs with any number of dimensions ($D$), while the compactification into the exponential solution occurs only for $D \geqslant 2$. For the $\Lambda$-term case only compactification into the exponential solution exists, and it only occurs for $D \geqslant 2$ as well. Our results, combined with the bounds on Gauss-Bonnet coupling and the $\Lambda$-term ($\alpha, \Lambda$, respectively) from other considerations, allow for the tightening of the existing constraints and forbid $\alpha < 0$.

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Sergey Pavluchenko. 2018-03-05. Realistic Compactification Models in Einstein-Gauss-Bonnet Gravity. https://doi.org/10.3390/particles1010004

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