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arXiv · 1609.01253

Fully stable cosmological solutions with a non-singular classical bounce

Anna Ijjas·Paul J. Steinhardt
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Abstract

We recently showed how it is possible to use a cubic Galileon action to construct classical cosmological solutions that enter a contracting null energy condition (NEC) violating phase, bounce at finite values of the scale factor and exit into an expanding NEC-satisfying phase without encountering any singularities or pathologies. A drawback of these examples is that singular behavior is encountered at some time either just before or just after the NEC-violating phase. In this Letter, we show that it is possible to circumvent this problem by extending our method to actions that include the next order ${\cal L}_4$ Galileon interaction. Using this approach, we construct non-singular classical bouncing cosmological solutions that are non-pathological for all times.

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BibTeXRIS

Anna Ijjas, Paul J. Steinhardt. 2020-11-18. Fully stable cosmological solutions with a non-singular classical bounce. https://doi.org/10.1016/j.physletb.2016.11.047

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