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arXiv · 1405.2515

Cosmological Constraints on Ghost Dark Energy in the Brans-Dicke Theory by Using MCMC Approach

Hamzeh Alavirad·Ahmad Sheykhi
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Abstract

By using a Markov Chain Monte Carlo simulation, we investigate cosmological constraints on the ghost dark energy (GDE) model in the framework of the Brans-Dicke (BD) theory. A combination of the latest observational data of the cosmic microwave background radiation data from seven-year WMAP, the baryon acoustic oscillation data form the SDSS, the supernovae type Ia data from the Union2 and the X-ray gas mass fraction data from the Chandra X-ray observations of the largest relaxed galaxy clusters are used to perform constraints on GDE in the BD cosmology. In this paper, we consider both flat and non-flat universes together with interaction between dark matter and dark energy. The main cosmological parameters are obtained as: $Ω_{\rm b}h^2= 0.0223^{+0.0016}_{-0.0013}$, $Ω_{\rm c}h^2=0.1149^{+0.0088}_{-0.0104}$ and $Ω_{\rm k}=0.0005^{+0.0025}_{-0.0073}$. In addition, the Brans-Dicke parameter $ω$ is estimated as $1/ω\simeq 0.002$.

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Hamzeh Alavirad, Ahmad Sheykhi. 2014-05-11. Cosmological Constraints on Ghost Dark Energy in the Brans-Dicke Theory by Using MCMC Approach. https://doi.org/10.1016/j.physletb.2014.05.023

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