论文标题
高红移$λ$ CDM宇宙学：垃圾箱还是不垃圾箱？
High Redshift $Λ$CDM Cosmology: To Bin or not to Bin?
论文作者
论文摘要
We construct observational Hubble $H(z)$ and angular diameter distance $D_{A}(z)$ mock data with baseline Planck $Λ$CDM input values, before fitting the $Λ$CDM model to study evolution of probability density functions (PDFs) of best fit cosmological parameters $(H_0, Ω_m, Ω_k)$ across redshift bins.我们发现，PDF峰仅与低红移（$ z \ Lessim 1 $）中的输入参数一致，以$ h（z）$和$ d_ {a}（z）$约束，以及当$ h（z）$和$ h（z）$和$ d_ {a}（z）$约束时的所有红移箱中。当未恢复输入参数时，我们观察到PDF向较大的$ω_m$ y值表现出非高斯尾巴，并在较小的$ω_m$ yublat下转移到（较不明显的）峰值。 PDF的这种扁平化预计为$ h（z）$和$ d_ {a}（z）$观测值仅约束宇宙学参数的组合，因此预计PDF均匀。我们的分析使我们可以选择将高红移数据集结出来，因为我们可能不太可能恢复Planck值，或进行完整的样本分析，以使$λ$ CDM推断对下层红移宇宙。
We construct observational Hubble $H(z)$ and angular diameter distance $D_{A}(z)$ mock data with baseline Planck $Λ$CDM input values, before fitting the $Λ$CDM model to study evolution of probability density functions (PDFs) of best fit cosmological parameters $(H_0, Ω_m, Ω_k)$ across redshift bins. We find that PDF peaks only agree with the input parameters in low redshift ($z \lesssim 1$) bins for $H(z)$ and $D_{A}(z)$ constraints, and in all redshift bins when $H(z)$ and $D_{A}(z)$ constraints are combined. When input parameters are not recovered, we observe that PDFs exhibit non-Gaussian tails towards larger $Ω_m$ values and shifts to (less pronounced) peaks at smaller $Ω_m$ values. This flattening of the PDF is expected as $H(z)$ and $D_{A}(z)$ observations only constrain combinations of cosmological parameters at higher redshifts, so uniform PDFs are expected. Our analysis leaves us with a choice to bin high redshift data in the knowledge that we may be unlikely to recover Planck values, or conduct full sample analysis that biases $Λ$CDM inferences to the lower redshift Universe.
