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arXiv · 1506.08162

Negative potentials and collapsing universes II

Roberto Giambò·John Miritzis·Koralia Tzanni
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Abstract

Completing a previous analysis started in [1], we study flat Friedmann--Lema\^{\i}tre--Robertson--Walker (FLRW) models with a perfect fluid matter source and a scalar field nonminimally coupled to matter, self--interacting with a potential that may attain negative values. We prove that the evolution generically forces the Hubble function to diverge to $-\infty$ in a finite time, except in case the potential exhibits a flat plateau at infinity (tending to zero from below); in that case we find conditions which may give rise to ever expanding or recollapsing cosmologies.

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Roberto Giambò, John Miritzis, Koralia Tzanni. 2015-06-26. Negative potentials and collapsing universes II. https://doi.org/10.1088/0264-9381/32/16/165017

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