论文标题
在块状宇宙中使用平稳宇宙距离的后果：i
Consequences of using a smooth cosmic distance in a lumpy universe: I
论文作者
论文摘要
我们如何适当地拟合基于理想化的Friedmann-Lema \^{} Tre Robertson-Walker Spacetime的模型与由笨拙宇宙中的单个位置进行的观测值？我们解决了这个问题的调查，该调查测量了银河系分布中重子振荡的烙印和IA型超新星型的峰值明显大小。这些可观察到的物品与宇宙学模型通过Alcock-Paczyński参数和距离红移关系有关。使用这些观察到的数据，使用这些相应的不均匀时空表达式，我们执行一个参数推断，假设背景Friedmann-LemaîtreRobertson-Walker模型是宇宙的正确模型。这个过程使我们能够估算最佳拟合哈勃速率和减速参数。我们发现，从Alcock-Paczyński参数的单极从距离距离红外关系确定的哈勃速率处于张力。后者为宇宙扩张提供了最佳拟合哈勃速率。 Alcock-Paczyński参数对哈勃速率的约束受到环境污染。当环境贡献仅限于哈勃流中的模式时，我们发现哈勃速率的（9-12）\％差异。最后，我们评论宇宙学方法在约束减速参数时的不足。
How do we appropriately fit a model based on an idealised Friedmann-Lema\^{}tre Robertson-Walker spacetime to observations made from a single location in a lumpy Universe? We address this question for surveys that measure the imprints of the baryon acoustic oscillation in galaxy distribution and the peak apparent magnitude of the Type Ia supernova. These observables are related to the cosmological model through the Alcock-Paczyński parameters and the distance-redshift relation. Using the corresponding inhomogeneous spacetime expressions of these as observed data, we perform a parameter inference assuming that the background Friedmann-Lemaître Robertson-Walker model is the correct model of the Universe. This process allows us to estimate the best fit Hubble rate and the deceleration parameter. We find that the inferred Hubble rate from the monopole of the Alcock-Paczyński parameters is in tension with the Hubble rate determined using the distance-redshift relation. The latter gives the best fit Hubble rate for the cosmological expansion. The constraint on the Hubble rate from the Alcock-Paczyński parameters is contaminated by the environment. When the environmental contribution is restricted to modes in the Hubble flow, we find about (9-12)\% discrepancy in the Hubble rate. Finally, we comment on the insufficiency of the method of cosmography in constraining the deceleration parameter.
