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Cosmological Perturbations in Brane-World Theories: Formalism

C. van de Bruck·M. Dorca·R. H. Brandenberger·A. Lukas
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Abstract

We develop a gauge-invariant formalism to describe metric perturbations in five-dimensional brane-world theories. In particular, this formalism applies to models originating from heterotic M-theory. We introduce a generalized longitudinal gauge for scalar perturbations. As an application, we discuss some aspects of the evolution of fluctuations on the brane. Moreover, we show how the five-dimensional formalism can be matched to the known four-dimensional one in the limit where an effective four-dimensional description is appropriate.

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C. van de Bruck, M. Dorca, R. H. Brandenberger, A. Lukas. 2000-11-29. Cosmological Perturbations in Brane-World Theories: Formalism. https://doi.org/10.1103/physrevd.62.123515

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