Pook-Kolb Daniel, Hennigar Robie A, Booth Ivan
Max-Planck-Institut für Gravitationsphysik (Albert Einstein Institute), Callinstrasse 38, 30167 Hannover, Germany.
Leibniz Universität Hannover, 30167 Hannover, Germany.
Phys Rev Lett. 2021 Oct 29;127(18):181101. doi: 10.1103/PhysRevLett.127.181101.
We resolve the fate of the two original apparent horizons during the head-on merger of two nonspinning black holes. We show that, following the appearance of the outer common horizon and subsequent interpenetration of the original horizons, they continue to exist for a finite period of time before they are individually annihilated by unstable marginally outer trapped surfaces (MOTSs). The inner common horizon vanishes in a similar, though independent, way. This completes the understanding of the analog of the event horizon's "pair of pants" diagram for the apparent horizon. Our result is facilitated by a new method for locating MOTSs based on a generalized shooting method. We also discuss the role played by the MOTS stability operator in discerning which among a multitude of MOTSs should be considered as black hole boundaries.
我们解析了两个非旋转黑洞正面合并过程中两个原始表观视界的命运。我们表明，在外部共同视界出现以及原始视界随后相互穿透之后，它们会在有限的时间内继续存在，然后才分别被不稳定的 marginally outer trapped surfaces（MOTSs）湮灭。内部共同视界以类似但独立的方式消失。这完善了对视界“短裤”图类似物的表观视界的理解。我们的结果得益于一种基于广义打靶法定位 MOTSs 的新方法。我们还讨论了 MOTS 稳定性算子在辨别众多 MOTS 中哪些应被视为黑洞边界时所起的作用。
