Hyperbolic inflationary model with nonzero curvature

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 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. (C) 2022 The Author(s). Published by Elsevier B.V.

Automated summary

In this study, we investigate the asymptotic behavior of solutions and search for attractors in a cosmological model called hyperbolic inflation. We find that two hyperbolic inflationary stages are stable solutions that can solve the flatness problem and describe acceleration. We also obtain a Milne-like attractor solution for the open model and investigate mirror solutions with opposite dynamical behaviors in the contracting branch.