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Brane World Cosmology, the CMB and the Radion

A. -C. Davis·Ph. Brax·C. van de Bruck
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Abstract

Recent developments in the theory of extra dimensions have opened up avenues to confront such theories with cosmological tests. We discuss a brane-world model with a bulk scalar field, motivated by supergravity. The low-energy effective action is derived and physical constraints on the parameters of the model discussed. The cosmological evolution of the brane-world moduli is investigated and it is shown that one of the moduli is a quintessence field. The CMB predictions are computed. Finally, the possibility that the radion field in brane-worlds could be a chameleon field is investigated.

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A. -C. Davis, Ph. Brax, C. van de Bruck. 2005-03-22. Brane World Cosmology, the CMB and the Radion. https://doi.org/10.1016/j.nuclphysbps.2005.04.052

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