English

Modified holographic Ricci dark energy coupled to interacting dark matter and a non interacting baryonic component

General Relativity and Quantum Cosmology 2013-04-02 v1 Cosmology and Nongalactic Astrophysics Space Physics

Abstract

We examine a Friedmann-Robertson-Walker universe filled with interacting dark matter, modified holographic Ricci dark energy (MHRDE), and a decoupled baryonic component.The estimations of the cosmic parameters with Hubble data lead to an age of the universe of 13.17Gyr13.17 {\rm Gyr} and show that the MHRDE is free from the cosmic-age problem at low redshift (0z20 \leq z \leq 2) in contrast to holographic Ricci dark energy (HRDE) case. We constrain the parameters with the Union2 data set and contrast with the Hubble data. We also study the behavior of dark energy at early times by taking into account the severe bounds found at recombination era and/or at big bang nucleosynthesis. The inclusion of a non interacting baryonic matter forces that the amount of dark energy at ztO(1)z_{t} \sim {\cal O}(1) changes abruptly implying that Ωx(z1100)=0.03\Omega_x (z\simeq 1100) =0.03, so the bounds reported by the forecast of Planck and CMBPol experiments are more favored for the MHRDE model than in the case of HRDE cutoff. For the former model, we also obtain that at high redshift the fraction of dark energy varies from 0.006 to 0.002, then the amount of Ωx\Omega_x at the big bang nucleosynthesis era does not disturb the observed Helium abundance in the universe provided that the bound Ωx(z1010)<0.21\Omega_{x}(z\simeq 10^{10})<0.21 is hold.

Keywords

Cite

@article{arxiv.1301.2737,
  title  = {Modified holographic Ricci dark energy coupled to interacting dark matter and a non interacting baryonic component},
  author = {Luis P. Chimento and Mónica I. Forte and Martín G. Richarte},
  journal= {arXiv preprint arXiv:1301.2737},
  year   = {2013}
}

Comments

11 pages, 6 figures, two columns. Accepted for publication in The European Physical Journal C (2013)