This review is an introduction to causal properties of general relativity. Topics include the Raychaudhuri equation, singularity theorems of Penrose and Hawking, the black hole area theorem, topological censorship, and the Gao-Wald theorem. The review is based on lectures at the 2018 summer program Prospects in Theoretical Physics at the Institute for Advanced Study, and also at the 2020 New Zealand Mathematical Research Institute summer school in Nelson, New Zealand.

中文翻译：

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光线，奇异点等等

本文是对广义相对论的因果性质的介绍。主题包括Raychaudhuri方程，Penrose和Hawking的奇异性定理，黑洞面积定理，拓扑检查和高-瓦尔德定理。这篇评论是基于高等研究院2018年夏季课程《理论物理的前景》以及新西兰尼尔森2020年新西兰数学研究所夏季学校的演讲的。