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The Diffusion of Passive Tracers in Laminar Shear Flow
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从大规模散装流量估计对标准宇宙学模型的挑战
1Department of Physics, Willamette University, Salem, OR 97301, USA.
概括
银河系的运动显示出大规模的质量流,这挑战了标准的宇宙学模型. 这种大批量流动.
科学领域:
- 宇宙学的宇宙学是什么?
- 天体物理学 天体物理学
- 宇宙的大规模结构宇宙的大规模结构
背景情况:
- 宇宙学原理认为,银河系运动在大尺度上应该很小.
- 几十年来,人们一直在暗示异常的大规模散装流,但数据质量存在有限的约束.
- 奇特的速度数据,比如来自CosmicFlows-4的数据,现在允许对宇宙学模型进行有意义的测试.
研究的目的:
- 为了测试宇宙学原理和标准宇宙学模型.
- 为了研究随着体积增加的大规模散装流的行为.
- 为了确定观察到的异常散装流的潜在来源.
主要方法:
- 使用最小方差 (MV) 方法来估计散装流量.
- 从CosmicFlows-4 (CF4) 目录中使用的数据.
- 在日益增长的半径的体积中分析了散装流.
主要成果:
- 发现大量流量的幅度随着分析体积的半径的增加而增加.
- 在[公式:参见文本]Mpc半径检测到显著的散装流量.
- 这种观察到的散装流在标准宇宙学模型中发生的概率很低 (0.003%).
结论:
- 这些发现挑战了标准宇宙学模型和宇宙学原理.
- 随着半径的增加,散流幅度的增加表明偏离了预期的宇宙学行为.
- 需要对这种大规模散装货物流的特征和来源进行进一步的调查.
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