arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2306.14014astro-ph.CO
收藏

尺度依赖引力相变的重建

Reconstruction of A Scale-Dependent Gravitational Phase Transition

Marzieh Farhang, Nima Khosravi

AI总结:

本研究通过尺度依赖的引力相变模型,利用多种宇宙学数据重建参数,调和了哈勃常数与σ8张力,未发现显著偏离广义相对论。

摘要:

在这项工作中,我们扩展了先前关于引力相变(GPT)及其向早期宇宙推广的唯象模型,通过让线性扰动爱因斯坦方程中的修正具有尺度依赖性。这些修正被表征为参数$μ(z,k)$和$γ(z,k)$相对于广义相对论(GR)中值的偏差。我们利用多种数据组合测量了修正后的$μ(z,k)$和$γ(z,k)$的尺度依赖振幅、定义相变的参数以及标准宇宙学参数。从扰动参数中,我们构建了引力本征模,这些本征模代表了数据最易探测到的扰动模式。我们在这些参数中未检测到与广义相对论的显著偏差。然而,由于新自由度导致的更大参数空间,使得在$Λ$CDM中相互矛盾的多种数据集得以调和。特别是,我们利用普朗克卫星测量的宇宙微波背景各向异性以及多种重子声学振荡测量,得到$H_0=71.9\pm 9.2$,这与局域哈勃测量结果一致。我们还发现,暗能量巡天与普朗克测量之间的$σ_8$张力被降低到小于$1σ$。

英文摘要:

In this work we extend our earlier phenomenological model for a gravitational phase transition (GPT) and its generalization to early times by letting the modifications in the linearly-perturbed Einstein equations be scale-dependent. These modifications are characterized as deviations of the parameters $μ(z,k)$ and $γ(z,k)$ from their values in general relativity (GR). The scale-dependent amplitudes of modified $μ(z,k)$ and $γ(z,k)$ and the parameters defining the phase transition, along with the standard cosmological parameters, are measured by various data combinations. Out of the perturbation parameters, we construct gravity eigenmodes which represent patterns of perturbations best detectable by data. We detect no significant deviation from GR in these parameters. However, the larger parameter space produced due to the new degrees of freedom allows for the reconciliation of various datasets which are in tension in $Λ$CDM. In particular, we find $H_0=71.9\pm 9.2$ from anisotropies of the Cosmic Microwave Background as measured by Planck and various measurements of the Baryonic Acoustic Oscillations, in agreement with local Hubble measurements. We also find that the $σ_8$ tension between the measurements of Dark Energy Survey and Planck is reduced to less than $1σ$.

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。

↑