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Multiple-scales analysis of cosmological perturbations in brane-worlds

Richard A. Battye·Andrew Mennim
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Abstract

We present a new approximation method for solving the equations of motion for cosmological tensor perturbations in a Randall-Sundrum brane-world model of the type with one brane in a five-dimensional anti-de Sitter spacetime. This method avoids the problem of coordinate singularities inherent in some methods. At leading order, the zero-mode solution replicates the evolution of perturbations in a four-dimensional Friedmann-Robertson-Walker universe in the absence of any tensor component to the matter perturbation on the brane. At next order, there is a mode-mixing effect, although, importantly, the zero-mode does not source any other modes.

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Richard A. Battye, Andrew Mennim. 2004-08-12. Multiple-scales analysis of cosmological perturbations in brane-worlds. https://doi.org/10.1103/physrevd.70.124008

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