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arXiv · 1804.02193

Dynamic compactification with stabilized extra dimensions in cubic Lovelock gravity

Dmitry Chirkov·Alex Giacomini·Alexey Toporensky
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Abstract

In this paper the dynamic compactification in Lovelock gravity with a cubic term is studied. The ansatz will be of space-time where the three dimensional space and the extra dimensions are constant curvature manifolds with independent scale factors. The numerical analysis shows that there exist a phenomenologically realistic compactification regime where the three dimensional hubble parameter and the extra dimensional scale factor tend to a constant. This result comes as surprise as in Einstein-Gauss-Bonnet gravity this regime exists only when the couplings of the theory are such that the theory does not admit a maximally symmetric solution (i.e. "geometric frustration"). In cubic Lovelock gravity however there always exists at least one maximally symmetric solution which makes it fundamentally different from the Einstein-Gauss-Bonnet case. Moreover, in opposition to Einstein-Gauss-Bonnet Gravity, it is also found that for some values of the couplings and initial conditions these compactification regimes can coexist with isotropizing solutions.

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Dmitry Chirkov, Alex Giacomini, Alexey Toporensky. 2018-04-06. Dynamic compactification with stabilized extra dimensions in cubic Lovelock gravity. https://doi.org/10.1007/s10714-018-2417-x

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