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arXiv · 1210.0781

Generalized ghost dark energy in Brans-Dicke theory

A. Sheykhi·E. Ebrahimi·Y. Yosefi
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Abstract

It was argued that the vacuum energy of the Veneziano ghost field of QCD, in a time-dependent background, can be written in the general form, $H + O(H^2)$, where $H$ is the Hubble parameter. Based on this, a phenomenological dark energy model whose energy density is of the form $ρ=αH+βH^{2}$ was recently proposed to explain the dark energy dominated universe. In this paper, we investigate this generalized ghost dark energy model in the setup of Brans-Dicke cosmology. We study the cosmological implications of this model. In particular, we obtain the equation of state and the deceleration parameters and a differential equation governing the evolution of this dark energy model. It is shown that the equation of state parameter of the generalized ghost dark energy can cross the phantom line ($w_D=-1$) in some range of the parameters spaces.

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A. Sheykhi, E. Ebrahimi, Y. Yosefi. 2013-07-23. Generalized ghost dark energy in Brans-Dicke theory. https://arxiv.org/abs/1210.0781

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