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Brane-world inflation without inflaton on the brane

Yoshiaki Himemoto·Misao Sasaki
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Abstract

Inspired by the Randall-Sundrum brane-world scenario, we investigate the possibility of brane-world inflation driven not by an inflaton field on the brane, but by a bulk, dilaton-like gravitational field. As a toy model for the dilaton-like gravitational field, we consider a minimally coupled massive scalar field in the bulk 5-dimensional spacetime, and look for a perturbative solution in the anti-de Sitter (AdS) background. For an adequate range of the scalar field mass, we find a unique solution that has non-trivial dependence on the 5th dimensional coordinate and that induces slow-roll inflation on the brane.

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Yoshiaki Himemoto, Misao Sasaki. 2001-01-26. Brane-world inflation without inflaton on the brane. https://doi.org/10.1103/physrevd.63.044015

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