论文标题
第一个同时测量哈勃常数和牛顿后参数
The first simultaneous measurement of Hubble constant and post-Newtonian parameter from Time-Delay Strong Lensing
论文作者
论文摘要
强烈的引力镜头是对宇宙学模型和重力的强大探针。迄今为止，已分别获得了任一域中的约束。我们提出了一种新的方法，可以同时限制宇宙学模型，特别是哈勃常数和牛顿后参数。使用强透镜的时间延迟宇宙学结合了偏转镜的恒星运动学，我们证明了哈勃常数和牛顿后参数分别以两个距离比率纳入，分别反映了镜头质量和动力学质量。通过重新分析H0licow协作的四个公开释放的镜头距离后代，可以获得哈勃常数和牛顿后参数的同时约束。 Our results suggests no deviation from the General Relativity, $γ_{\texttt{PPN}}=0.87^{+0.19}_{-0.17}$ with a Hubble constant favors the local Universe value, $H_0=73.65^{+1.95}_{-2.26}$ km s$^{-1}$ mpc $^{ - 1} $。最后，我们通过使用时间延迟的强镜头来预测重力测试的鲁棒性，以实现未来几年我们期望的约束。我们发现，来自40个镜头的联合约束能够达到Newtonian Parameter的$ 7.7 \％$ $，Hubble常数$ 1.4 \％$ $。
Strong gravitational lensing has been a powerful probe of cosmological models and gravity. To date, constraints in either domain have been obtained separately. We propose a new methodology through which the cosmological model, specifically the Hubble constant, and post-Newtonian parameter can be simultaneously constrained. Using the time-delay cosmography from strong lensing combined with the stellar kinematics of the deflector lens, we demonstrate the Hubble constant and post-Newtonian parameter are incorporated in two distance ratios which reflect the lensing mass and dynamical mass, respectively. Through the reanalysis of the four publicly released lenses distance posteriors from the H0LiCOW collaboration, the simultaneous constraints of Hubble constant and post-Newtonian parameter are obtained. Our results suggests no deviation from the General Relativity, $γ_{\texttt{PPN}}=0.87^{+0.19}_{-0.17}$ with a Hubble constant favors the local Universe value, $H_0=73.65^{+1.95}_{-2.26}$ km s$^{-1}$ Mpc$^{-1}$. Finally, we forecast the robustness of gravity tests by using the time-delay strong lensing for constraints we expect in the next few years. We find that the joint constraint from 40 lenses are able to reach the order of $7.7\%$ for the post-Newtonian parameter and $1.4\%$ for Hubble constant.
