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arXiv · 1707.00302

Inhomogeneous compact extra dimensions

K. A. Bronnikov·R. I. Budaev·A. V. Grobov·A. E. Dmitriev·Sergey G. Rubin
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Abstract

We show that an inhomogeneous compact extra space possesses two necessary features --- their existence does not contradict the observable value of the cosmological constant $\Lambda_4$ in pure $f(R)$ theory, and the extra dimensions are stable relative to the "radion mode" of perturbations, the only mode considered. For a two-dimensional extra space, both analytical and numerical solutions for the metric are found, able to provide a zero or arbitrarily small $\Lambda_4$. A no-go theorem has also been proved, that maximally symmetric compact extra spaces are inconsistent with 4D Minkowski space in the framework of pure $f(R)$ gravity.

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K. A. Bronnikov, R. I. Budaev, A. V. Grobov, A. E. Dmitriev, Sergey G. Rubin. 2017-07-02. Inhomogeneous compact extra dimensions. https://doi.org/10.1088/1475-7516%2F2017%2F10%2F001

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