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arXiv · 1807.00987

Dynamical analysis of Brans-Dicke Universe with inverse power-law effective potential

Jonghyun Sim·Jiwon Park·Tae Hoon Lee
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Abstract

We study Brans-Dicke cosmology with an inverse power-law effective potential. By using dynamical analyses, we search for fixed points corresponding to the radiation-like matter and dark energy-dominated era of our Universe, and the stability of fixed points is also investigated. We find phase space trajectories which are attracted to the stable point of the dark energy-dominated era from unstable fixed points like matter-dominated era of the Universe. The dark energy comes from effective potentials of the Brans-Dicke field, whose variation (related to the time-variation of the gravitational coupling constant) is shown to be in good agreement with observational data.

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Jonghyun Sim, Jiwon Park, Tae Hoon Lee. 2018-07-03. Dynamical analysis of Brans-Dicke Universe with inverse power-law effective potential. https://doi.org/10.1142/s0217732320500947

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