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The failure of cosmological perturbation theory in the new ekpyrotic and cyclic ekpyrotic scenarios

D H Lyth
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Abstract

Cosmological perturbation theory fails in the new ekpyrotic and cyclic ekpyrotic scenarios, before the scale factor of the Universe reaches zero. As a result, a recently-proposed recipe for evolving the curvature perturbation through the bounce in these scenarios cannot be justified.

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D H Lyth. 2002-01-08. The failure of cosmological perturbation theory in the new ekpyrotic and cyclic ekpyrotic scenarios. https://doi.org/10.1016/s0370-2693(01)01438-1

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