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Density perturbations in Kaluza--Klein theories during a de Sitter phase

Julio Fabris·Mairi Sakellariadou
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Abstract

In the context of Kaluza-Klein theories, we consider a model in which the universe is filled with a perfect fluid described by a barotropic equation of state. An analysis of density perturbations employing the synchronous gauge shows that there are cases where these perturbations have an exponential growth during a de Sitter phase evolution in the external space.

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Julio Fabris, Mairi Sakellariadou. 1997-01-09. Density perturbations in Kaluza--Klein theories during a de Sitter phase. https://doi.org/10.1088/0264-9381%2F14%2F3%2F014

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