We consider the black hole information problem in an explicitly defined spacetime modeling black hole evaporation. Using this context we review basic aspects of the problem, with a particular effort to be unambiguous about subtle topics, for instance precisely what is meant by entropy in various circumstances. We then focus on questions of unitarity, and argue that commonly invoked semiclassical statements of long term, evaporation time, and Page time ‘unitarity’ may all be violated even if physics is fundamentally unitary. This suggests that there is no horizon firewall. We discuss how the picture is modified for regular (nonsingular) evaporation models. We also compare our conclusions to recent holographic studies, and argue that they are mutually compatible.

我们在明确定义的时空建模黑洞蒸发中考虑黑洞信息问题。使用这个上下文，我们回顾了问题的基本方面，特别努力使微妙的主题明确无误，例如在各种情况下熵的确切含义。然后，我们专注于单一性问题，并认为即使物理学从根本上是单一的，也可能会违反通常引用的长期、蒸发时间和 Page 时间“单一性”的半经典陈述。这表明没有地平线防火墙。我们讨论如何为常规（非奇异）蒸发模型修改图片。我们还将我们的结论与最近的全息研究进行比较，并认为它们是相互兼容的。