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Gauge invariant cosmological perturbation theory for braneworlds

Alain Riazuelo·Filippo Vernizzi·Danièle Steer·Ruth Durrer
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Abstract

We derive the gauge invariant perturbation equations for a 5-dimensional bulk spacetime in the presence of a brane. The equations are derived in full generality, without specifying a particular energy content of the bulk or the brane. We do not assume Z_2 symmetry, and show that the degree of freedom associated with brane motion plays a crucial role. Our formalism may also be used in the Z_2 symmetric case where it simplifies considerably.

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Alain Riazuelo, Filippo Vernizzi, Danièle Steer, Ruth Durrer. 2002-05-21. Gauge invariant cosmological perturbation theory for braneworlds. https://arxiv.org/abs/hep-th/0205220

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