The physics of information, and applications in quantum gravity, cosmology and engineering

无论信息在现实世界中以何种物理方式呈现，它都受量子理论和相对论定律的约束。对于信息的传统物理表示，比如纸上的字母，经典物理定律当然就足够了。然而，过去几年的研究表明，当信息在亚原子水平上和/或在强引力的存在下表现或处理时，会产生戏剧性的新效果。然后，量子理论的定律，如不确定性原理和纠缠，以及相对论的定律，如有限的最大通信速度和不可穿透的视界，对信息的表示和处理方式产生了非常深远的影响，无论是在原理上还是在实践中。

Whichever way information is physically represented in the real world, it is subject to the laws of quantum theory and relativity. In the case of traditional physical representations of information, such as letters on paper, the laws of classical physics suffice, of course, for a good description. Research over the past few years has shown, however, that there are dramatic new effects when information is represented or processed on the subatomic level and/or in the presence of strong gravity. Then, the laws of quantum theory, such as the uncertainty principle and entanglement, and the laws of relativity, such as the finite maximum speed of communication and unpenetrable horizons, yield a very profound impact on the way that information can be represented and processed, both in principle and in practice.