Hees A, Do T, Roberts B M, Ghez A M, Nishiyama S, Bentley R O, Gautam A K, Jia S, Kara T, Lu J R, Saida H, Sakai S, Takahashi M, Takamori Y
SYRTE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, LNE, 61 avenue de l'Observatoire 75014 Paris, France.
Department of Physics and Astronomy, University of California, Los Angeles, California 90095, USA.
Phys Rev Lett. 2020 Feb 28;124(8):081101. doi: 10.1103/PhysRevLett.124.081101.
Searching for space-time variations of the constants of Nature is a promising way to search for new physics beyond general relativity and the standard model motivated by unification theories and models of dark matter and dark energy. We propose a new way to search for a variation of the fine-structure constant using measurements of late-type evolved giant stars from the S star cluster orbiting the supermassive black hole in our Galactic Center. A measurement of the difference between distinct absorption lines (with different sensitivity to the fine structure constant) from a star leads to a direct estimate of a variation of the fine structure constant between the star's location and Earth. Using spectroscopic measurements of five stars, we obtain a constraint on the relative variation of the fine structure constant below 10^{-5}. This is the first time a varying constant of nature is searched for around a black hole and in a high gravitational potential. This analysis shows new ways the monitoring of stars in the Galactic Center can be used to probe fundamental physics.
寻找自然常数的时空变化，是在统一理论以及暗物质与暗能量模型的推动下，探索超越广义相对论和标准模型的新物理的一种很有前景的方式。我们提出了一种新方法，利用对环绕银河系中心超大质量黑洞的S星团中晚期演化巨星的测量，来寻找精细结构常数的变化。对恒星不同吸收线（对精细结构常数敏感度不同）之间差异的测量，能直接估算出恒星所在位置与地球之间精细结构常数的变化。通过对五颗恒星的光谱测量，我们得到了精细结构常数相对变化低于10⁻⁵ 的约束。这是首次在黑洞周围和高引力势环境中寻找变化的自然常数。该分析展示了利用对银河系中心恒星的监测来探究基础物理学的新途径。
