论文标题
Ultravista Galaxy调查的分形分析
Fractal Analysis of the UltraVISTA Galaxy Survey
论文作者
论文摘要
本文试图测试大型星系分布是否可以将其表征为分形系统。开发并应用于Ultravista Galaxy调查，适用于相对论设置中具有单个分形尺寸$ d $的星系分形结构的工具。给出了与每个红移箱中的红移极限相对应的体积限制样品图。使用标准$λ$ CDM宇宙学模型的分形分析应用于$ 0.1 \ le z \ le 4 $的降低子样本，整个样本在$ 0.1 \ le z \ le 6 $之内。使用了三个相对论距离，亮度距离$ d_l $，红移距离$ d_z $和星系距离$ d_g $，因为对于$ z \ gtrsim 0.3 $ 0.3 $的数据，相对论效应使得相同的$ z $这些距离会产生不同的值。结果显示，在还原和完整的样品中，数据作为单个分形星系结构的连续和完整的样品中都有两个连续的红移范围。对于简化的子样本，我们发现分形维度为$ d = \ left（1.58 \ pm0.20 \右）$ for $ z <1 $，而$ d = \ left（0.59 \ pm0.28 \ right）$ for $ 1 \ le le z \ le z \ le 4 $。完整的样本产生$ d = \ left（1.63 \ pm0.20 \右）$ for $ z <1 $和$ d = \ left（0.52 \ pm0.29 \ right）$ for $ 1 \ le le z \ le6 $。这些结果与Conde-Saavedra等人发现的结果一致。 （2015; arxiv：1409.5409v1），在同等红移深度上进行了类似的分析，对更有限的调查进行了调查，并表明，要么存在尚不清楚的观察性偏见，导致分形尺寸的下降，或者银河聚类的偏见可能更加稀疏，而不是太稀疏而不是过于主导的。
This paper seeks to test if the large-scale galaxy distribution can be characterized as a fractal system. Tools appropriate for describing galaxy fractal structures with a single fractal dimension $D$ in relativistic settings are developed and applied to the UltraVISTA galaxy survey. A graph of volume-limited samples corresponding to the redshift limits in each redshift bins for absolute magnitude is presented. Fractal analysis using the standard $Λ$CDM cosmological model is applied to a reduced subsample in the range $0.1\le z \le 4$, and the entire sample within $0.1\le z\le 6$. Three relativistic distances are used, the luminosity distance $d_L$, redshift distance $d_z$ and galaxy area distance $d_G$, because for data at $z\gtrsim 0.3$ relativistic effects are such that for the same $z$ these distance definitions yield different values. The results show two consecutive and distinct redshift ranges in both the reduced and complete samples where the data behave as a single fractal galaxy structure. For the reduced subsample we found that the fractal dimension is $D=\left(1.58\pm0.20\right)$ for $z<1$, and $D=\left(0.59\pm0.28\right)$ for $1\le z\le 4$. The complete sample yielded $D=\left(1.63\pm0.20\right)$ for $z<1$ and $D=\left(0.52\pm0.29\right)$ for $1\le z\le6$. These results are consistent with those found by Conde-Saavedra et al. (2015; arXiv:1409.5409v1), where a similar analysis was applied to a much more limited survey at equivalent redshift depths, and suggest that either there are yet unclear observational biases causing such decrease in the fractal dimension, or the galaxy clustering was possibly more sparse and the universe void dominated in a not too distant past.
