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arXiv · 1505.06903

Scalar field deformations of Lambda-CDM cosmology

Artur Alho·Claes Uggla
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Abstract

This paper treats nonrelativistic matter and a scalar field $ϕ$ with a monotonically decreasing potential minimally coupled to gravity in flat Friedmann-Lemaître-Robertson-Walker cosmology. The field equations are reformulated as a three-dimensional dynamical system on an extended compact state space, complemented with cosmographic diagrams. A dynamical systems analysis provides global dynamical results describing possible asymptotic behavior. It is shown that one should impose \emph{global and asymptotic} bounds on $λ=-V^{-1}\,dV/dϕ$ to obtain viable cosmological models that continuously deform $Λ$CDM cosmology. In particular we introduce a regularized inverse power-law potential as a simple specific example.

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BibTeXRIS

Artur Alho, Claes Uggla. 2015-11-04. Scalar field deformations of Lambda-CDM cosmology. https://doi.org/10.1103/physrevd.92.103502

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