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arXiv · 0805.3782

Scalar Field as Dark Energy Accelerating Expansion of the Universe

O. Sergijenko·B. Novosyadlyj
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Abstract

The features of a homogeneous scalar field $ϕ$ with classical Lagrangian $L=ϕ_{;i}ϕ^{;i}/2-V(ϕ)$ and tachyon field Lagrangian $L=-V(ϕ)\sqrt{1-ϕ_{;i}ϕ^{;i}}$ causing the observable accelerated expansion of the Universe are analyzed. The models with constant equation-of-state parameter $w_{de}=p_{de}/ρ_{de}<-1/3$ are studied. For both cases the fields $ϕ(a)$ and potentials $V(a)$ are reconstucted for the parameters of cosmological model of the Universe derived from the observations. The effect of rolling down of the potential $V(ϕ)$ to minimum is shown.

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O. Sergijenko, B. Novosyadlyj. 2008-05-27. Scalar Field as Dark Energy Accelerating Expansion of the Universe. https://doi.org/10.3103/s0884591308060019

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