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arXiv · 1202.4228

Holographic Dark Energy Characterized by the Total Comoving Horizon and Insights to Cosmological Constant and Coincidence Problem

Zhuo-Peng Huang·Yue-Liang Wu
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Abstract

The observed acceleration of the present universe is shown to be well explained by the holographic dark energy characterized by the total comoving horizon of the universe ($η$HDE). It is of interest to notice that the very large primordial part of the comoving horizon generated by the inflation of early universe makes the $η$HDE behave like a cosmological constant. As a consequence, both the fine-tuning problem and the coincidence problem can reasonably be understood with the inflationary universe and holographical principle. We present a systematic analysis and obtain a consistent cosmological constraint on the $η$HDE model based on the recent cosmological observations. It is found that the $η$HDE model gives the best-fit result $Ω_{m0}=0.270$ ($Ω_{de0}=0.730$) and the minimal $χ^2_{min}=542.915$ which is compatible with $χ^2_{Λ{\rm CDM}}=542.919$ for the $Λ$CDM model.

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Zhuo-Peng Huang, Yue-Liang Wu. 2012-05-03. Holographic Dark Energy Characterized by the Total Comoving Horizon and Insights to Cosmological Constant and Coincidence Problem. https://doi.org/10.1103/physrevd.85.103007

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