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arXiv · hep-ph/9909481

Cosmological 3-Brane Solutions

P. Kanti·I. I. Kogan·K. A. Olive·M. Pospelov
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Abstract

We analyze cosmological equations in the brane world scenario with one extra space-like dimension. We demonstrate that the cosmological equations can be reduced to the usual 4D Friedmann type if the bulk energy-momentum tensor is different from zero. We then generalize these equations to the case of a brane of finite thickness. We also demonstrate that when the bulk energy-momentum tensor is different from zero, the extra space-like dimension can be compactified with a single brane and show that the stability of the radius of compactification implies standard cosmology and vice versa. For a brane of finite thickness, we provide a solution such that the 4D Planck scale is related to the fundamental scale by the thickness of the brane. In this case, compactification of the extra dimension is unnecessary.

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P. Kanti, I. I. Kogan, K. A. Olive, M. Pospelov. 1999-11-10. Cosmological 3-Brane Solutions. https://doi.org/10.1016/s0370-2693(99)01218-6

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