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arXiv · 0908.0606

Interacting new agegraphic dark energy in non-flat Brans-Dicke cosmology

Ahmad Sheykhi
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Abstract

We construct a cosmological model of late acceleration based on the new agegraphic dark energy model in the framework of Brans-Dicke cosmology where the new agegraphic energy density $\rho_{D}= 3n^2 m^2_p /\eta^{2}$ is replaced with $\rho_{D}= {3n^2\phi^2}/({4\omega \eta^2}$). We show that the combination of Brans-Dicke field and agegraphic dark energy can accommodate $w_D = -1 $ crossing for the equation of state of \textit{noninteracting} dark energy. When an interaction between dark energy and dark matter is taken into account, the transition of $w_D $ to phantom regime can be more easily accounted for than when resort to the Einstein field equations is made. In the limiting case $\alpha = 0$ $(\omega\to \infty)$, all previous results of the new agegraphic dark energy in Einstein gravity are restored.

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Ahmad Sheykhi. 2009-08-05. Interacting new agegraphic dark energy in non-flat Brans-Dicke cosmology. https://doi.org/10.1103/physrevd.81.023525

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