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arXiv · 2301.08652

Cosmic bounce and phantom-like equation of state from tunnelling

Jean Alexandre·Silvia Pla
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Abstract

We allow a scalar field on a flat FLRW background metric to tunnel between two degenerate vacua. The resulting true vacuum state then violates the Null Energy Condition, and the corresponding homogeneous fluid induces a bounce, after which it has a phantom-like equation of state and asymptotically leads to a de Sitter phase. The mechanism presented here requires no exotic matter or modified gravity, it is purely generated by quantum fluctuations and is valid for a generic double well potential.

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Jean Alexandre, Silvia Pla. 2023-01-20. Cosmic bounce and phantom-like equation of state from tunnelling. https://doi.org/10.1007/jhep05(2023)145

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