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arXiv · hep-th/0010063

Evolution of cosmological perturbations in a brane-universe

David Langlois
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Abstract

The present article analyses the impact on cosmology, in particular on the evolution of cosmological perturbations, of the existence of extra-dimensions. The model considered here is that of a five-dimensional Anti-de Sitter spacetime where ordinary matter is confined to a brane-universe. The homogeneous cosmology is recalled. The equations governing the evolution of cosmological perturbations are presented in the most transparent way: they are rewritten in a form very close to the equations of standard cosmology with two types of corrections: a. corrections due to the unconventional evolution of the homogeneous solution, which change the background-dependent coefficients of the equations; b. corrections due to the curvature along the fifth dimension, which act as source terms in the evolution equations.

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David Langlois. 2000-10-10. Evolution of cosmological perturbations in a brane-universe. https://doi.org/10.1103/physrevlett.86.2212

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