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arXiv · 2106.07958

Singularity scattering laws for bouncing cosmologies: a brief overview

Philippe G. LeFloch
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Abstract

For contracting/expanding bouncing cosmologies, the formulation of junction conditions at a bouncing was recently revisited by the author in collaboration with B. Le Floch and G. Veneziano. The regime of interest here is the so-called quiescent regime, in which a monotone behavior of the metric is observed and asymptotic expansions can be derived. Here, we overview our new methodology based on the notion of {\sl singularity scattering maps} and {\sl cyclic spacetimes}, and we present our main conclusions. In particular, we provide a classification of all allowed bouncing junction conditions, including three universal laws.

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Philippe G. LeFloch. 2021-06-15. Singularity scattering laws for bouncing cosmologies: a brief overview. https://arxiv.org/abs/2106.07958

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