منابع مشابه
Reconstructing K-essence
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There are a number of mathematical theorems in the literature on the dynamics of cosmological models with accelerated expansion driven by a positive cosmological constant Λ or a nonlinear scalar field with potential V (quintessence) which do not assume homogeneity and isotropy from the beginning. The aim of this paper is to generalize these results to the case of k-essence models which are defi...
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We analyze the implications of having a divergent speed of sound in k-essence cosmological models. We first study a known theory of that kind, for which the Lagrangian density depends linearly on the time derivative of the k-field. We show that consistency requires that the potential of the k-field be of the inverse square form. Then, we review the known result that the corresponding power-law ...
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We propose an holographic k-essence and dilaton models of dark energy. The correspondence between the k-essence and dilaton energy densities with the holographic density, allows the reconstruction of the potential and the fields for the k-essence and dilaton models in flat FRW background. For the proposed infrared cut-off the reconstruction was made for the two cases of the constant α: for α < ...
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ژورنال
عنوان ژورنال: Astrophysics and Space Science
سال: 2016
ISSN: 0004-640X,1572-946X
DOI: 10.1007/s10509-016-2846-5