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arXiv · 1209.3726

Scalar field cosmology in phase space

Valerio Faraoni·Charles S. Protheroe
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Abstract

Using dynamical systems methods, we describe the evolution of a minimally coupled scalar field and a Friedmann-Lemaitre-Robertson-Walker universe in the context of general relativity, which is relevant for inflation and late-time quintessence eras. Focussing on the spatially flat case, we examine the geometrical structure of the phase space, locate the equilibrium points of the system (de Sitter spaces with a constant scalar field), study their stability through both a third-order perturbation analysis and Lyapunov functions, and discuss the late-time asymptotics. As we do not specify the scalar field's origin or its potential, the results are independent of the high-energy model.

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Valerio Faraoni, Charles S. Protheroe. 2012-09-17. Scalar field cosmology in phase space. https://doi.org/10.1007/s10714-012-1462-0

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