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arXiv · 2308.00765

Tunnelling-induced cosmic bounce in the presence of anisotropies

Jean Alexandre·Katy Clough·Silvia Pla
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Abstract

If we imagine rewinding the universe to early times, the scale factor shrinks and the existence of a finite spatial volume may play a role in quantum tunnelling effects in a closed universe. It has recently been shown that such finite volume effects dynamically generate an effective equation of state that could support a cosmological bounce. In this work we extend the analysis to the case in which a (homogeneous) anisotropy is present, and identify a criteria for a successful bounce in terms of the size of the closed universe and the properties of the quantum field.

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Jean Alexandre, Katy Clough, Silvia Pla. 2023-08-01. Tunnelling-induced cosmic bounce in the presence of anisotropies. https://doi.org/10.1103/physrevd.108.103515

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