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arXiv · hep-th/0306109

Cosmological Perturbations in a Big Crunch/Big Bang Space-time

Andrew J. Tolley·Neil Turok·Paul J. Steinhardt
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Abstract

A prescription is developed for matching general relativistic perturbations across singularities of the type encountered in the ekpyrotic and cyclic scenarios i.e. a collision between orbifold planes. We show that there exists a gauge in which the evolution of perturbations is locally identical to that in a model space-time (compactified Milne mod Z_2) where the matching of modes across the singularity can be treated using a prescription previously introduced by two of us. Using this approach, we show that long wavelength, scale-invariant, growing-mode perturbations in the incoming state pass through the collision and become scale-invariant growing-mode perturbations in the expanding hot big bang phase.

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Andrew J. Tolley, Neil Turok, Paul J. Steinhardt. 2003-06-12. Cosmological Perturbations in a Big Crunch/Big Bang Space-time. https://doi.org/10.1103/physrevd.69.106005

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