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arXiv · 2203.01598

Hyperbolic inflationary model with nonzero curvature

Andronikos Paliathanasis·Genly Leon
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Abstract

We consider a cosmological model consisting of two scalar fields defined in the hyperbolic plane known as hyperbolic inflation. For the background space, we consider a homogeneous and isotropic spacetime with nonzero curvature. We study the asymptotic behaviour of solutions and we search for attractors in the expanding regime. We prove that two hyperbolic inflationary stages are stable solutions that can solve the flatness problem and describe acceleration for both open and closed models, and additionally we obtain a Milne-like attractor solution for the open model. We also investigate the contracting branch obtaining mirror solutions with the opposite dynamical behaviours.

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Andronikos Paliathanasis, Genly Leon. 2022-05-20. Hyperbolic inflationary model with nonzero curvature. https://doi.org/10.1016/j.physletb.2022.137407

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