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

TL;DR

This paper develops a cosmological model combining new agegraphic dark energy with Brans-Dicke theory, showing it can explain late-time acceleration and crossing of the phantom divide, especially with dark energy-dark matter interaction.

Contribution

It introduces a novel integration of agegraphic dark energy into Brans-Dicke cosmology, allowing for equation of state crossing and easier phantom regime transition.

Findings

Model accommodates $w_D = -1$ crossing in noninteracting case.

Interaction facilitates transition to phantom regime.

Recovers Einstein gravity results when $eta=0$.

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.