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arXiv 2107.07538astro-ph.CO
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具有几何和增长的标准宇宙学模型的检验

A Test of the Standard Cosmological Model with Geometry and Growth

Uendert Andrade, Dhayaa Anbajagane, Rodrigo von Marttens, Dragan Huterer, Jailson Alcaniz

备注：
27 pages, 10 figures. References updated; matches version published in JCAP
发表信息：
JCAP 11 (2021) 014
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摘要：

我们进行一般测试的$Λ{\rm CDM}$和$w {\rm CDM}$宇宙学模型的膨胀历史的几何结构上的增长的限制进行比较。具体来说，我们将总物质能量密度$Ω_M$和（对于$w {\rm CDM}$）暗能量状态方程$w$分成两个参数：一个参数捕获几何形状，另一个参数捕获生长。我们约束我们的分裂模型使用当前的宇宙学数据，包括Ia型超新星，重子声振荡，红移空间扭曲，引力透镜，和宇宙微波背景（CMB）各向异性。我们专注于两项任务：（i）约束由参数$ΔΩ_M \equiv Ω_M^{\rm grow}-Ω_M^{\rm geom}$和$Δw \equiv w^{\rm grow}-w^{\rm geom}$捕获的与标准模型的偏差，以及（ii）研究CMB和弱透镜效应之间的$S_8$张力是否可以转化为几何和生长之间的张力，即$ΔΩ_M \neq 0$、$Δw \neq 0$。在分离的$Λ{\rm CDM}$和$w {\rm CDM}$病例中，我们结合所有数据的结果与$ΔΩ_M = 0$和$Δw = 0$一致。如果我们忽略BAO/RSD数据并约束分裂的$w {\rm CDM}$宇宙学，我们发现数据在$3.6σ$显著性上更倾向于$Δw<0$，在$4.2σ$证据上更倾向于$ΔΩ_M>0$。我们还发现，对于CMB和弱透镜，$ΔΩ_M$和$S_8$是相关的，CMB显示出稍强的相关性。在我们的扩展模型中，轮廓的普遍加宽确实减轻了$S_8$张力，但允许的$ΔΩ_M$的非零值并不包含$S_8$值，该值将指向几何形状和生长之间的不匹配作为张力的起源。

英文摘要：

We perform a general test of the $Λ{\rm CDM}$ and $w {\rm CDM}$ cosmological models by comparing constraints on the geometry of the expansion history to those on the growth of structure. Specifically, we split the total matter energy density, $Ω_M$, and (for $w {\rm CDM}$) dark energy equation of state, $w$, into two parameters each: one that captures the geometry, and another that captures the growth. We constrain our split models using current cosmological data, including type Ia supernovae, baryon acoustic oscillations, redshift space distortions, gravitational lensing, and cosmic microwave background (CMB) anisotropies. We focus on two tasks: (i) constraining deviations from the standard model, captured by the parameters $ΔΩ_M \equiv Ω_M^{\rm grow}-Ω_M^{\rm geom}$ and $Δw \equiv w^{\rm grow}-w^{\rm geom}$, and (ii) investigating whether the $S_8$ tension between the CMB and weak lensing can be translated into a tension between geometry and growth, i.e. $ΔΩ_M \neq 0$, $Δw \neq 0$. In both the split $Λ{\rm CDM}$ and $w {\rm CDM}$ cases, our results from combining all data are consistent with $ΔΩ_M = 0$ and $Δw = 0$. If we omit BAO/RSD data and constrain the split $w {\rm CDM}$ cosmology, we find the data prefers $Δw<0$ at $3.6σ$ significance and $ΔΩ_M>0$ at $4.2σ$ evidence. We also find that for both CMB and weak lensing, $ΔΩ_M$ and $S_8$ are correlated, with CMB showing a slightly stronger correlation. The general broadening of the contours in our extended model does alleviate the $S_8$ tension, but the allowed nonzero values of $ΔΩ_M$ do not encompass the $S_8$ values that would point toward a mismatch between geometry and growth as the origin of the tension.

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。

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