高维非高斯性质的量化及其对宇宙学的费舍尔分析的影响
Core Francisco Park1, Erwan Allys2, Francisco Villaescusa-Navarro3,4
1Harvard University, 17 Oxford Street, Cambridge, MA 02138, USA; corefranciscopark@g.harvard.edu.
The Astrophysical journal
|September 8, 2023
概括
如果统计测试假定高斯性,宇宙参数约束可能会误导. 本研究使用非高斯度测试来提高费舍尔矩阵计算对宇宙密度场的准确性.
科学领域:
- 宇宙学的宇宙学是什么?
- 统计物理学的统计物理.
- 天体物理学 天体物理学
背景情况:
- 仅仅功率光谱就不足以表征非高斯宇宙密度场.
- 提出了各种统计数据,以改善从非高斯领域提取信息.
- 费舍尔矩阵形式主义通常假定统计数据的多变量高斯分布,可能导致不准确的宇宙参数约束.
研究的目的:
- 从宇宙统计中识别和删除非高斯元件.
- 评估非高斯性对费舍尔矩阵计算宇宙学参数的影响.
- 为评估费舍尔矩阵分析的可靠性提供一个可靠的方法.
主要方法:
- 利用两个统计测试来检测功率光谱,双光谱,标记功率光谱和波纹散射变换 (WST) 中的非高斯性.
- 应用了高斯化技术,从这些统计数据中删除非高斯元件.
- 使用Quijote模拟对高斯统计进行了费舍尔矩阵计算.
主要成果:
- 在各种宇宙统计数据中识别了非高斯性.
- 证明了删除非高斯元件可以改变参数约束的最大系数为~2.2.
- 展示了非高斯统计数据如何在费舍尔矩阵分析中产生人为紧密的边界.
结论:
- 非高斯性测试对于验证宇宙学中的费舍尔矩阵计算至关重要.
- 高斯化统计为宇宙学参数提供了更强大的约束.
- 开发的方法和发布的代码提高了宇宙参数估计的可靠性.
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