论文标题
测试黑洞与活动地平线望远镜的射手图像a $^*$的图像
Testing black hole mimickers with the Event Horizon Telescope image of Sagittarius A$^*$
论文作者
论文摘要
事件地平线望远镜（EHT）最近观察到了超质量紧凑型对象的图像和阴影sagittarius a $^*$（sgr a $^*$）。根据EHT的合作，观察到的图像与Kerr黑洞的预期外观一致。但是，众所周知，某些非Kerr对象可能模仿Kerr Black Hole的许多属性，因此，它们的阴影可能与SGR A $^*$的观察到的阴影一致。在这项工作中，我们考虑了两个黑洞模仿并研究它们的阴影。第一个模仿是辛普森和维瑟（Simpson）和维塞尔（Visser）最近提出的静态静态对称的黑色弹跳时空的旋转概括，那里中央的schwarzschild奇异性被最小的表面取代。第二个是$γ$ - metric，它是真空爱因斯坦方程的静态，轴向对称的单数解，而无需事件范围。我们通过将它们的阴影与SGR A $^*$观察到的阴影进行比较，对这些黑洞模仿者的参数进行了约束。
The Event Horizon Telescope (EHT) has recently observed the image and shadow of the supermassive compact object Sagittarius A$^*$ (Sgr A$^*$). According to the EHT collaboration, the observed image is consistent with the expected appearance of a Kerr black hole. However, it is well-known that some non-Kerr objects may mimic many of the properties of the Kerr black hole, and hence, their shadows might be consistent with the observed shadow of Sgr A$^*$. In this work, we consider two black hole mimickers and study their shadows. The first mimicker is a rotating generalisation of the recently proposed static, spherically symmetric black-bounce spacetime by Simpson and Visser where the central Schwarzschild singularity is replaced by a minimal surface. The second one is the $γ$-metric which is a static, axially symmetric singular solution of the vacuum Einstein's equations without an event horizon. We put constraint on the parameters of these black hole mimickers by comparing their shadows with the one observed for Sgr A$^*$.
