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Strong coupling in brane-induced gravity in five dimensions

V. A. Rubakov
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Abstract

Brane-induced gravity in five dimensions (Dvali--Gabadadze--Porrati model) exhibits modification of gravity at ultra-large distances, $r\gg r_c = M_{Pl}^2/M^3$ where $M$ is the five-dimensional gravity scale. This makes the model potentially interesting for explaining the observed acceleration of the Universe. We argue, however, that it has an intrinsic intermediate energy scale $(M^9/M_{Pl}^4)^{1/5}$. At higher energies, the model is strongly coupled. For $r_c$ of order of the present Hubble size, the strong coupling regime occurs at distanced below tens of metres.

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V. A. Rubakov. 2003-03-13. Strong coupling in brane-induced gravity in five dimensions. https://arxiv.org/abs/hep-th/0303125

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