论文标题
使用$γ$ metric限制球形对称性的偏差
Constraining deviations from spherical symmetry using $ γ$-metric
论文作者
论文摘要
$γ$ -Spacetime度量是爱因斯坦方程的静态和轴向对称的真空解决方案。这个时空代表着裸露的奇异性，它具有额外的参数$γ$，表示与球形对称性的偏差。在这项工作中，我们研究了通过天体物理观测来限制变形参数的可能性。我们从弱和强场极限的重力镜头开始，并计算相应的挠度角，以表明只有强场透镜观测值才能独立约束$γ$。后来，我们研究了其他两个经典重力测试：夏皮罗时间延迟和圆周的动力。我们表明，在这两个实验中，变形参数仅在近乎围巾中影响可观察到。
The $ γ$-spacetime metric is a static and axially symmetric vacuum solution of the Einstein equation. This spacetime represents a naked singularity and it has an extra parameter $ γ$ which signifies deviations from spherical symmetry. In this work, we study the possibility of constraining the deformation parameter with astrophysical observations. We start with gravitational lensing in the weak and strong-field limit and calculate the respective deflection angles to show that only strong-field lensing observations will be able to constrain $ γ$ independently. Later we study two other classical tests of gravity: Shapiro time delay and precession of perihelion. We show that, out of these two experiments, the deformation parameter affects the observables only in perihelion shift.
