标题： 使用恒星、脉冲星和事件视界望远镜对人马座 A* 进行的黑洞无毛定理定量检验 显示英文标题

标题： A Quantitative Test of the No-Hair Theorem with Sgr A* using stars, pulsars, and the Event Horizon Telescope

摘要： 银河系中心的黑洞人马座A*（Sgr A*）在宇宙中所有已知黑洞中具有最大的质量-距离比。 这一特性使Sgr A*成为测试引力毛发定理的理想目标。 在不久的将来，仪器的重大发展将提供工具，通过观测恒星轨道的相对论效应、脉冲星计时以及吸积流在视界面尺度上的图像，来进行高精度的空间时间研究。 我们在此探讨利用这三种类型的观测来测量黑洞时空属性的可能性。 我们表明，使用恒星和脉冲星轨道测量黑洞自旋和四极矩时的相关不确定性几乎与通过测量黑洞在周围发射物上投射的阴影形状和大小得到的不确定性正交。 因此，结合这三种类型的观测将使我们能够评估和量化每种测量中的系统偏差和不确定性，并导致对引力毛发定理的高度精确的定量检验。 显示英文摘要

摘要： The black hole in the center of the Milky Way, Sgr A*, has the largest mass-to-distance ratio among all known black holes in the Universe. This property makes Sgr A* the optimal target for testing the gravitational no-hair theorem. In the near future, major developments in instrumentation will provide the tools for high-precision studies of its spacetime via observations of relativistic effects in stellar orbits, in the timing of pulsars, and in horizon-scale images of its accretion flow. We explore here the prospect of measuring the properties of the black-hole spacetime using all these three types of observations. We show that the correlated uncertainties in the measurements of the black-hole spin and quadrupole moment using the orbits of stars and pulsars are nearly orthogonal to those obtained from measuring the shape and size of the shadow the black hole casts on the surrounding emission. Combining these three types of observations will, therefore, allow us to assess and quantify systematic biases and uncertainties in each measurement and lead to a highly accurate, quantitative test of the gravitational no-hair theorem.