Scalar field cosmology in the energy phase-space -- unified description of dynamics

Marek Szydlowski; Orest Hrycyna

doi:10.1088/1475-7516/2009/01/039

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arXiv · 0811.1493

Scalar field cosmology in the energy phase-space -- unified description of dynamics

Marek Szydlowski·Orest Hrycyna

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Abstract

In this letter we apply dynamical system methods to study all evolutional paths admissible for all initial conditions of the FRW cosmological model with a non-minimally coupled to gravity scalar field and a barotropic fluid. We choose "energy variables" as phase variables. We reduce dynamics to a 3-dimensional dynamical system for an arbitrary potential of the scalar field in the phase space variables. After postulating the potential parameter $Γ$ as a function of $λ$ (defined as $-V'/V$) we reduce whole dynamics to a 3-dimensional dynamical system and study evolutional paths leading to current accelerating expansion. If we restrict the form of the potential then we will obtain a 2-dimensional dynamical system. We use the dynamical system approach to find a new generic quintessence scenario of approaching to the de Sitter attractor which appears only for the case of non-vanishing coupling constant.

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Marek Szydlowski, Orest Hrycyna. 2009-01-26. Scalar field cosmology in the energy phase-space -- unified description of dynamics. https://doi.org/10.1088/1475-7516%2F2009%2F01%2F039

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