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没有解的抑制:通过银河系聚类限制结构形成和暗能量
Shi-Fan Chen1, Mikhail M Ivanov2, Oliver H E Philcox3,4
1School of Natural Sciences, <a href="https://ror.org/00f809463">Institute for Advanced Study</a>, 1 Einstein Drive, Princeton, New Jersey 08540, USA.
Physical review letters
|December 23, 2024
概括
这项研究分析了BOSS星系聚类数据,发现低红移处被抑制的宇宙结构. 结果挑战了标准宇宙学模型,并提出了潜在的数据系统学或需要新的理论框架.
科学领域:
- 宇宙学的宇宙学是什么?
- 天体物理学 天体物理学
- 银河系的进化 银河系的进化
背景情况:
- 兰巴达冷暗物质 (ΛCDM) 模型是标准宇宙学模型.
- 以前的研究表明,宇宙微波背景 (CMB) 数据和低红移观测之间的潜在紧张关系.
研究的目的:
- 为了对巴里昂振荡光谱调查 (BOSS) 星系聚类数据进行全面分析.
- 为了限制宇宙学参数,并调查暗能量的性质.
- 评估BOSS数据与其他宇宙学数据集之间的一致性.
主要方法:
- 对BOSS星系的功率光谱和双光谱多极的扰动性全形分析.
- 纳入声振荡 (BAO) 和与普朗克CMB引力透镜交叉相关.
- 在 ΛCDM 框架内限制宇宙学参数.
主要成果:
- 约束物质密度分数Ωm=0.3138±0.0086,哈勃常数H0=68.23±0.78公里/秒/Mpc,以及 σ8=0.688±0.026 (S8=0.703±0.029).
- 与普朗克 ΛCDM 模型相比,在低红移时观察到显著 (4.5σ) 的宇宙结构抑制.
- 在将BOSS数据与DESI BAO和PantheonPlus超新星结合时,没有发现动态暗能量 (DDE) 的偏好,暗能量与宇宙常数一致.
结论:
- 观察到的宇宙结构的抑制可能表明数据中的剩余系统性或需要新的理论模型.
- 宇宙学一致性仍然是一个挑战,需要进一步调查不同数据集和理论预测之间的潜在差异.
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