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arXiv · 1501.04606

No Open or Flat Bouncing Cosmologies in Einstein Gravity

Maulik K. Parikh
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Abstract

We show that bouncing open or flat Friedmann-Robertson-Walker cosmologies are inconsistent with worldsheet string theory to first approximation. Specifically, the Virasoro constraint translates to the null energy condition in spacetime at leading order in the alpha-prime expansion. Thus one must go beyond minimally-coupled Einstein gravity in order to find bounce solutions.

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Maulik K. Parikh. 2015-01-23. No Open or Flat Bouncing Cosmologies in Einstein Gravity. https://arxiv.org/abs/1501.04606

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