论文标题
通过时间延迟和宇宙计时仪观测来重新访问哈勃常数,空间曲率和宇宙学
Revisiting the Hubble constant, spatial curvature and cosmography with time-delay and cosmic chronometer observations
论文作者
论文摘要
在本文中,我们走得更远,并提出了一种独立于宇宙学模型的方法,以同时确定具有强大的镜头时间延迟测量值的哈勃常数和宇宙曲率,而没有任何先前关于宇宙内容的假设。我们使用的数据包括最近研究的六个精心镜头类星体的汇编,而宇宙天文序列数据用于通过cosmographic参数重建距离。在三阶Taylor扩展的框架和(2,1)用于杂志分析的订单padé近似中,我们的结果提供了模型无关的估计,对哈勃常数$ H_0 = 72.24 = 72.24^{+2.73} _ { - 2.52} 〜km〜s 72.45^{+1.95} _ { - 2.02} 〜km〜s^{ - 1} 〜mpc^{ - 1} $,这与SH0ES协作源自本地距离阶梯得出的距离非常一致。 The measured cosmic curvature $Ω_k=0.062^{+0.117}_{-0.078}$ and $Ω_k=0.069^{+0.116}_{-0.103}$ shows that zero spatial curvature is supported by the current observations of strong lensing time delays and cosmic chronometers.施加空间平稳性的先验会导致更精确(在1.6 $ \%$级别)确定哈勃常数$ h_0 = 70.47 = 70.47^{+1.14} _ { - 1.15} 〜km〜s^{ - 1} 〜mpc^{ - 1} 〜km〜s^{ - 1} 〜mpc^{ - 1} $,一个位于\ textit {planck}的结果与SH0ES协作之间的值。 If a prior of local (SH0ES) $H_0$ measurement is adopted, the curvature parameter constraint can be further improved to $Ω_k=0.123^{+0.060}_{-0.046}$ and $Ω_k=0.101^{+0.090}_{-0.072}$, supporting no significant deviation from a flat universe.最后,我们还讨论了帕德近似在$ z \ sim2.3 $内重建宇宙扩展历史的有效性,考虑到其在贝叶斯信息标准(BIC)中的表现更好。
In this paper, we go further and propose a cosmological model-independent approach to simultaneously determine the Hubble constant and cosmic curvature with strong lensing time-delay measurements, without any prior assumptions regarding the content of the Universe. The data we use comprises the recent compilation of six well studied strongly lensed quasars, while the cosmic chronometer data are utilized to reconstruct distances via cosmographic parameters. In the framework of third-order Taylor expansion and (2, 1) order Padé approximation for for cosmographic analysis, our results provides model-independent estimation of the Hubble constant $H_0 = 72.24^{+2.73}_{-2.52} ~km~s^{-1}~Mpc^{-1}$ and $H_0 = 72.45^{+1.95}_{-2.02} ~km~s^{-1}~Mpc^{-1}$, which is well consistent with that derived from the local distance ladder by SH0ES collaboration. The measured cosmic curvature $Ω_k=0.062^{+0.117}_{-0.078}$ and $Ω_k=0.069^{+0.116}_{-0.103}$ shows that zero spatial curvature is supported by the current observations of strong lensing time delays and cosmic chronometers. Imposing the prior of spatial flatness leads to more precise (at 1.6$\%$ level) determination of the Hubble constant $H_0=70.47^{+1.14}_{-1.15} ~km~s^{-1}~Mpc^{-1}$ and $H_0=71.66^{+1.15}_{-1.57} ~km~s^{-1}~Mpc^{-1}$, a value located between the results from \textit{Planck} and SH0ES collaboration. If a prior of local (SH0ES) $H_0$ measurement is adopted, the curvature parameter constraint can be further improved to $Ω_k=0.123^{+0.060}_{-0.046}$ and $Ω_k=0.101^{+0.090}_{-0.072}$, supporting no significant deviation from a flat universe. Finally, we also discuss the effectiveness of Padé approximation in reconstructing the cosmic expansion history within the redshift range of $z\sim2.3$, considering its better performance in the Bayes Information Criterion (BIC).