宇宙微波背景温度宇宙学
Cosmic microwave background temperature cosmography
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中文总结 AI 辅助
研究利用宇宙学成像方法，通过天体物理测量约束温度-红移关系对标准模型的违反，探讨不同方法和变量选择影响，发现违反被限制在百分之几水平，单一非标准参数可描述，还表明直接拟合斜率与FIRAS兼容，标准宇宙学知识在此不适用。
中文摘要 AI 辅助
温度-红移关系\(T(z)=T_0(1+z)\)是标准宇宙学模型的基石，但在许多有物理动机的扩展模型中会被违反，比如光子数不守恒时。我们将宇宙学的一种与模型无关的方法——宇宙学成像方法应用于此可观测量，利用跨越红移范围\(0\leq z\leq6.34\)的天体物理苏尼亚耶夫-泽尔多维奇效应和高分辨率光谱测量来约束对标准关系的违反。我们探讨了不同宇宙学成像方法和膨胀变量选择的影响，并将宇宙学成像约束与在利马的规范绝热扩展模型中用相同数据得到的约束进行比较。虽然这些选择有一定影响，但总体上我们发现这种违反被限制在百分之几的水平，并且一个单一的非标准参数就足以描述它们。我们还表明，温度-红移关系的直接拟合斜率与从FIRAS推断出的斜率兼容（但略小），并且基于标度因子展开的标准宇宙学知识不适用于此可观测量，例如帕德近似相对于普通泰勒级数没有有意义的优势。
英文摘要
The temperature-redshift relation, $T(z)=T_0(1+z)$, is a cornerstone of the standard cosmological model, but it is violated in many physically motivated extensions thereof, e.g. when photon number is not conserved. We apply the methodology of cosmography, a model-independent approach to cosmology, to this observable, and use astrophysical Sunyaev-Zeldovich and high-resolution spectroscopic measurements spanning the redshift range $0\le z\le6.34$, to constrain violations of the standard relation. We explore the impact of different cosmographic approaches and expansion variable choices and also compare the cosmographic constraints with those obtained, with the same data, in the canonical adiabatic extension model of Lima. While these choices have some impact, overall we find that such violations are constrained to percent level, and that a single non-standard parameter suffices to describe them. We also show that the directly fitted slope of the temperature-redshift relation is compatible with (but slightly smaller than) the one inferred from FIRAS, and that standard cosmography lore, based on scale factor expansions, does not apply to this observable, e.g. Padé approximants have no meaningful advantage over plain Taylor series.
