将量子引力理论的全息原理应用于暗能量（DE）问题，迄今已提出了三种全息DE模型：原始全息暗能量（HDE）模型、年龄记录暗能量（ADE）模型和全息里奇暗能量（RDE）模型。本文利用Union+ CFA 3的397颗Ia型超新星（SNIa）的最新观测数据、威尔金森微波各向异性探测器（WMAP 5）5年观测的宇宙微波背景（CMB）位移参数和斯隆数字巡天（SDSS）的重子声学振荡（BAO）测量数据，对这三个模型进行了最佳拟合分析。分析表明，对于HDE，为$χ_{min}^{2}=465.912$ ;对于RDE，为$χ_{min}^{2}=483.130$ ;对于ADE，为$χ_{min}^{2}=481.694$。在这些模型中，HDE模型可以给出最小的$χ^2_{min}$。此外，我们还使用贝叶斯证据（BE）作为模型选择标准进行比较。发现HDE、ADE和RDE的$Δ\ln \mathrm{BE}= -0.86$分别为$Δ\ln \mathrm{BE}= -0.86$、-5.17和-8.14。因此，HDE模型似乎更受观测数据的青睐。
英文摘要：
The holographic principle of quantum gravity theory has been applied to the dark energy (DE) problem, and so far three holographic DE models have been proposed: the original holographic dark energy (HDE) model, the agegraphic dark energy (ADE) model, and the holographic Ricci dark energy (RDE) model. In this work, we perform the best-fit analysis on these three models, by using the latest observational data including the Union+CFA3 sample of 397 Type Ia supernovae (SNIa), the shift parameter of the cosmic microwave background (CMB) given by the five-year Wilkinson Microwave Anisotropy Probe (WMAP5) observations, and the baryon acoustic oscillation (BAO) measurement from the Sloan Digital Sky Survey (SDSS). The analysis shows that for HDE, $χ_{min}^{2}=465.912$; for RDE, $χ_{min}^{2}=483.130$; for ADE, $χ_{min}^{2}=481.694$. Among these models, HDE model can give the smallest $χ^2_{min}$. Besides, we also use the Bayesian evidence (BE) as a model selection criterion to make a comparison. It is found that for HDE, ADE, and RDE, $Δ\ln \mathrm{BE}= -0.86$, -5.17, and -8.14, respectively. So, it seems that the HDE model is more favored by the observational data.
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Holographic Ricci dark energy: Current observational constraints, quintom feature, and the reconstruction of scalar-field dark energy
在这项工作中，我们考虑的宇宙学约束的全息里奇暗能量提出的高等。[Phys. Rev. D 79，043511（2009）]，利用现有的观测数据。全息Ricci暗能量的主要特征由模型中的正数值参数$α$决定。当$α<1/2$时，全息里奇暗能量将表现出类似五等分的行为;即，它的状态方程将跨越宇宙常数边界$w=-1$。参数$α$只能通过观察确定。因此，利用观测数据约束参数$α$，对于刻画暗能量的演化特征和预测宇宙的命运具有非常重要的意义。本文利用307颗Ia型超新星的Union样本、Wilkinson微波各向异性探测器5年观测给出的宇宙微波背景位移参数和Sloan数字巡天的重子声学振荡测量结果，导出了全息Ricci暗能量模型的约束条件。联合分析给出了最佳拟合结果（$σ$不确定度为1）：$α=0.359^{+0.024}_{-0.025}$和$Ω_{\rm m0}=0.318^{+0.026}_{-0.024}$。也就是说，根据观测，全息利玛窦暗能量呈现出五分之一的特征。最后，根据宇宙学约束的结果，我们讨论了基于全息Ricci真空能量的标量场暗能量重构问题。
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By combining cosmological probes at low, intermediate and high redshifts, we investigate the observational viability of a class of models with interaction in the dark sector. We perform a Bayesian analysis using the latest data sets of type Ia supernovae, baryon acoustic oscillations, the angular acoustic scale of the cosmic microwave background, and measurements of the expansion rate. When combined with the current measurement of the local expansion rate obtained by the Hubble Space Telescope, we find that these observations provide evidence in favour of interacting models with respect to the…
This work is the reconstruction of the interaction rate of holographic dark energy whose infrared cut-off scale is set by the Hubble length. We have reconstructed the interaction rate between dark matter and the holographic dark energy for a specific parameterization of the effective equation of state parameter. We have obtained observational constraints on the model parameters using the latest Type Ia Supernova (SNIa), Baryon Acoustic Oscillations (BAO) and Cosmic Microwave Background (CMB) radiation datasets. We have found that for the present model, the interaction rate increases with expan…
In the literature, it was proposed that the growth index $γ$ is useful to distinguish the scenarios of dark energy and modified gravity. In the present work, we consider the constraints on the growth index $γ$ by using the latest observational data. To be model-independent, we use cosmography to describe the cosmic expansion history, and also expand the general $γ(z)$ as a Taylor series with respect to redshift $z$ or $y$-shift, $y=z/(1+z)$. We find that the present value $γ_0=γ(z=0)\simeq 0.42$ (for most of viable $f(R)$ theories) is inconsistent with the latest observational data at high con…
This paper is devoted to the analysis of a class of $F(R)$ gravity, where additional logarithmic corrections are assumed. The gravitational action includes an exponential term and a $R^2$ inflationary term, both with logarithmic corrections. This model can unify an early time inflationary era and also the late time acceleration of the universe expansion. This model is deeply analysed, confronting with recent observational data coming from the largest Pantheon Type Ia supernovae sample, the latest measurements of the Hubble parameter $H(z)$, manifestations of Baryon Acoustic Oscillations and Co…
The paper deals with a theoretical model for interacting Tsallis holographic dark energy (THDE) whose infrared (IR) cut-off scale is set by the Hubble length. The interaction $Q$ between the dark sectors (dark energy and pressureless dark matter) of the universe has been assumed to be non-gravitational in nature. The functional form of $Q$ is chosen in such a way that it reproduces well known and most used interactions as special cases. We then study the nature of the THDE density parameter, the equation of state parameter, the deceleration parameter and the jerk parameter for this interacting…
We investigate the observational constraints on three typical brane inflation models by considering the latest local measurement of the Hubble constant in the global fit. We also employ other observational data, including the Planck 2015 CMB data, the BICEP2/Keck Array B-mode data, and the baryon acoustic oscillations data, in our analysis. Previous studies have shown that the addition of the latest local $H_{0}$ measurement favors a larger spectral index, and can exert a significant influence on the model selection of inflation. In this work, we investigate its impacts on the status of brane …
Reconstructions of $f(\mathcal{P})$ and $f(\mathcal{Q})$ gravity models from $(m,n)$-type Barrow Holographic Dark Energy: Analysis and Observational Constraints
In this study we combine the expansion and the growth data in order to investigate the ability of the three most popular holographic dark energy models, namely event future horizon, Ricci scale and Granda-Oliveros IR cutoffs, to fit the data. Using a standard $χ^2$ minimization method we place tight constraints on the free parameters of the models. Based on the values of the Akaike and Bayesian information criteria we find that two out of three holographic dark energy models are disfavored by the data, because they predict a non-negligible amount of dark energy density at early enough times. A…
We investigate the growth of matter fluctuations in holographic dark energy cosmologies. First we use an overall statistical analysis involving the latest observational data in order to place constraints on the cosmological parameters. Then we test the range of validity of the holographic dark energy models at the perturbation level and its variants from the concordance $Λ$ cosmology. Specifically, we provide a new analytical approach in order to derive, for the first time, the growth index of matter perturbations. Considering a homogeneous holographic dark energy we find that the growth index…
