Very compact objects probe extreme gravitational fields and may be the key to understand outstanding puzzles in fundamental physics. These include the nature of dark matter, the fate of spacetime singularities, or the loss of unitarity in Hawking evaporation. The standard astrophysical description of collapsing objects tells us that massive, dark and compact objects are black holes. Any observation suggesting otherwise would be an indication of beyond-the-standard-model physics. Null results strengthen and quantify the Kerr black hole paradigm. The advent of gravitational-wave astronomy and precise measurements with very long baseline interferometry allow one to finally probe into such foundational issues. We overview the physics of exotic dark compact objects and their observational status, including the observational evidence for black holes with current and future experiments.

非常紧凑的物体探测极端的引力场，可能是理解基础物理学中突出难题的关键。其中包括暗物质的性质、时空奇点的命运或霍金蒸发中统一性的丧失。对坍缩物体的标准天体物理学描述告诉我们，质量大、黑暗且致密的物体就是黑洞。任何表明其他情况的观察都将表明物理学超出了标准模型。空结果强化并量化了克尔黑洞范式。引力波天文学的出现和超长基线干涉测量的精确测量使人们最终能够探讨这些基本问题。我们概述了奇异的暗致密天体的物理学及其观测状态，包括当前和未来实验中黑洞的观测证据。