论文标题
在晚期宇宙的扩展中，摇摆不定的表现
Inevitable manifestation of wiggles in the expansion of the late Universe
论文作者
论文摘要
Using the fact that the comoving angular diameter distance to the last scattering surface is strictly constrained almost model independently, we show that, for any model agreeing with the standard $Λ$CDM model on its background dynamics at $z\sim0$ and size of the comoving sound horizon at last scattering, the deviations of the Hubble radius from the one of the standard $Λ$CDM model must be a member of the set of admissible wavelets.以该框架为特征的模型家族还提供了各种功能的非平凡振荡行为，这些函数定义了宇宙的运动学，即使小波本身非常简单。我们还讨论了将这些运动学归因于第一，暗能量的后果，其次是不同的引力耦合强度。利用一些最简单的小波，我们证明了该框架在描述Baryon声学振荡（BAO）数据方面的能力，而无需对宇宙微波背景测量的一致性进行任何修改。该框架还为哈勃参数和深色能量密度的非参数观察重建中发现的颠簸提供了自然的解释，作为某些BAO数据建议的倾角的补偿，并质疑其存在的物理现实。我们注意到，在模型之上利用此框架，这些框架既与宇宙微波背景和局部$ H_0 $测量结果都一致，却被BAO数据固定，可以通过可以自然可以容纳BAO数据的小波的摇摆性质来复活这些模型。最后，我们还建议缩小合理的可允许小波集，以进一步改善我们的框架，从可行的宇宙学模型的预期运动学或第一个原理基本物理（例如能量条件）施加条件。
Using the fact that the comoving angular diameter distance to the last scattering surface is strictly constrained almost model independently, we show that, for any model agreeing with the standard $Λ$CDM model on its background dynamics at $z\sim0$ and size of the comoving sound horizon at last scattering, the deviations of the Hubble radius from the one of the standard $Λ$CDM model must be a member of the set of admissible wavelets. The family of models characterized by this framework also offers nontrivial oscillatory behaviours in various functions that define the kinematics of the Universe, even when the wavelets themselves are very simple. We also discuss the consequences of attributing these kinematics to, first, dark energy, and second, varying gravitational coupling strength. Utilizing some simplest wavelets, we demonstrate the competence of this framework in describing the baryon acoustic oscillation (BAO) data without any modifications to the agreement with cosmic microwave background measurements. This framework also provides a natural explanation for the bumps found in nonparametric observational reconstructions of the Hubble parameter and dark energy density as compensations of the dips suggested by some BAO data, and questions the physical reality of their existence. We note that utilizing this framework on top of the models that agree with both the cosmic microwave background and local $H_0$ measurements but are held back by BAO data, one may resurrect these models through the wiggly nature of wavelets that can naturally accommodate the BAO data. Finally, we also suggest narrowing the plausible set of admissible wavelets to further improve our framework by imposing conditions from expected kinematics of a viable cosmological model or first principle fundamental physics such as energy conditions.
