arXiv 1409.31152014-09-09gr-qc

Brans-Dicke宇宙学中HDE与GO红外截止相互作用参数的最佳值

Best values of parameters for interacting HDE with GO IR-cutoff in Brans-Dicke cosmology

A. Khodam-Mohammadi, E. Karimkhani, A. Sheykhi

备注：: 20 pages, 10 figures
发表信息：: Int.J.Mod. Phys.D, 23, 14500813 (2014)
DOI：: 10.1142/S0218271814500813

摘要：

在Brans-Dicke（BD）宇宙学框架下研究了具有Granda-Oliveros（GO）红外截止的相互作用全息暗能量（HDE）.在平坦的FRW宇宙中，我们得到了HDE的状态方程参数$w_D$、有效状态方程参数$w_{\mathrm{eff}}$、减速参数$q $和声速的平方$v_s^2$.我们表明，在晚些时候，宇宙符合问题可以得到缓解。在无相互作用的情况下，HDE可以给出BD宇宙学中统一的暗物质-暗能量分布，只是不能解决未来的符合问题。通过对状态方程参数的研究，我们看到了幻影鸿沟是可以跨越的。利用最新的观测数据，我们计算了BD框架下相互作用HDE的最佳参数值。计算减速参数意味着对于红移$z\geq 0.5$发生了从减速到加速阶段的转变。最后，我们研究了该模型的稳定性，发现在BD宇宙学框架下，只要我们采用$β=0.44$和$b^2<0.35$，GO截止的HDE可以导致一个稳定的DE支配宇宙，这是观测所青睐的.这与爱因斯坦引力中的HDE模型形成对比，该模型不会导致稳定的DE支配宇宙。

英文摘要：

We investigate the interacting holographic dark energy (HDE) with Granda-Oliveros (GO) IR-cutoff in the framework of Brans-Dicke (BD) cosmology. We obtain the equation of state (EoS) parameter of HDE, $w_D$, the effective EoS parameter $w_{\mathrm{eff}}$, the deceleration parameter $q $ and the squared of sound speed $v_s^2$ in a flat FRW universe. We show that at late time the cosmic coincidence problem can be alleviated. Also we show that for non-interacting case, HDE can give a unified dark matter-dark energy profile in BD cosmology, except that it cannot solve the coincidence problem in the future. By studying the equation of state parameter, we see that the phantom divide may be crossed. Using the latest observational data, we calculate the best values of the parameters for interacting HDE in BD framework. Computing the deceleration parameter implies that the transition from deceleration to the acceleration phase occurred for redshift $z\geq 0.5$. Finally, we investigate the sound stability of the model, and find that HDE with GO cutoff in the framework of BD cosmology can lead to a stable DE-dominated universe favored by observations, provided we take $β=0.44$ and $b^2<0.35$. This is in contrast to HDE model in Einstein gravity which does not lead to a stable DE dominated universe.

机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。

摘要：

英文摘要：

相关论文