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arXiv · hep-th/0009010

Density perturbations in the brane-world

Christopher Gordon·Roy Maartens
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Abstract

In Randall-Sundrum-type brane-world cosmologies, density perturbations generate Weyl curvature in the bulk, which in turn backreacts on the brane via stress-energy perturbations. On large scales, the perturbation equations contain a closed system on the brane, which may be solved without solving for the bulk perturbations. Bulk effects produce a non-adiabatic mode, even when the matter perturbations are adiabatic, and alter the background dynamics. As a consequence, the standard evolution of large-scale fluctuations in general relativity is modified. The metric perturbation on large-scales is not constant during high-energy inflation. It is constant during the radiation era, except at most during the very beginning, if the energy is high enough.

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BibTeXRIS

Christopher Gordon, Roy Maartens. 2000-11-24. Density perturbations in the brane-world. https://doi.org/10.1103/physrevd.63.044022

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