The complete gravitational collapse of a body in general relativity will result in the formation of a black hole. Although the black hole is classically stable, quantum particle creation processes will result in the emission of Hawking radiation to infinity and corresponding mass loss of the black hole, eventually resulting in the complete evaporation of the black hole. Semiclassical arguments strongly suggest that, in the process of black hole formation and evaporation, a pure quantum state will evolve to a mixed state, i.e. there will be 'information loss'. There has been considerable controversy over this issue for more than 40 years. In this review, we present the arguments in favor of information loss, and analyze some of the counter-arguments and alternative possibilities.

中文翻译：

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信息丢失

广义相对论中物体的完全引力坍缩将导致黑洞的形成。虽然黑洞在经典上是稳定的，但量子粒子的产生过程会导致霍金辐射发射到无限远，黑洞相应的质量损失，最终导致黑洞完全蒸发。半经典论证强烈表明，在黑洞形成和蒸发的过程中，纯量子态会演化为混合态，即存在“信息丢失”。40多年来，这个问题一直存在着相当大的争议。在这篇评论中，我们提出了支持信息丢失的论点，并分析了一些反论点和替代可能性。