Cosmic variance and the measurement of the local Hubble parameter.
Cosmic variance and the measurement of the local Hubble parameter.
复制标题
DOI：
10.1103/physrevlett.110.241305
复制
发表时间：
2013-03
影响因子：
8.6
通讯作者：
V. Marra;L. Amendola;I. Sawicki;W. Valkenburg
中科院分区：
文献类型：
--
作者：
V. Marra;L. Amendola;I. Sawicki;W. Valkenburg
在宇宙膨胀率的两个独立约束之间存在大约9%的差异，相当于2.4 σ：一个间接来自宇宙微波背景和重子声振荡，另一个直接来自红移和源距离之间关系的局部测量。我们认为，考虑到当地的引力势在观察者的位置，这种紧张局势-加强了最近的普朗克结果-是部分缓解和宇宙学的标准模型的一致性增加。我们估计，局部哈勃常数的测量受到约2.4%（将局部样本限制在红移z > 0.010）或1.3%（将其限制在z > 0.023）的宇宙方差的影响，这是一个比已经考虑的更重要的修正。尽管如此，我们表明，人们需要一个非常罕见的波动，以充分解释哈勃速率的偏移。如果这种张力进一步加强，超越标准模型的宇宙学可能是必要的。
There is an approximately 9% discrepancy, corresponding to 2.4 σ, between two independent constraints on the expansion rate of the Universe: one indirectly arising from the cosmic microwave background and baryon acoustic oscillations and one more directly obtained from local measurements of the relation between redshifts and distances to sources. We argue that by taking into account the local gravitational potential at the position of the observer this tension--strengthened by the recent Planck results--is partially relieved and the concordance of the Standard Model of cosmology increased. We estimate that measurements of the local Hubble constant are subject to a cosmic variance of about 2.4% (limiting the local sample to redshifts z > 0.010) or 1.3% (limiting it to z > 0.023), a more significant correction than that taken into account already. Nonetheless, we show that one would need a very rare fluctuation to fully explain the offset in the Hubble rates. If this tension is further strengthened, a cosmology beyond the Standard Model may prove necessary.