Limit on nonlocality in any world in which communication complexity is not trivial
Limit on nonlocality in any world in which communication complexity is not trivial
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DOI：
10.1103/physrevlett.96.250401
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发表时间：
2006-06-30
影响因子：
8.6
通讯作者：
Unger, F
中科院分区：
文献类型：
--
作者：
Brassard, G;Buhrman, H;Unger, F
贝尔证明了量子纠缠使两个类空分离的部分能够表现出经典不可能的相关性。尽管这些相关性比任何经典的可实现的东西都要强大，但它们不能被利用来使瞬时（比光速更快）通信成为可能。然而，波佩斯库和罗利希已经证明，可以定义更强的相关性，在这种相关性下，即时通信仍然是不可能的。这就提出了一个问题：为什么量子力学所能实现的相关性在那些保持因果关系的相关性中不是最大的？我们给出了这个问题的部分答案表明，稍微强的相关性将导致在一个世界中，通信的复杂性变得微不足道。
Bell proved that quantum entanglement enables two spacelike separated parties to exhibit classically impossible correlations. Even though these correlations are stronger than anything classically achievable, they cannot be harnessed to make instantaneous (faster than light) communication possible. Yet, Popescu and Rohrlich have shown that even stronger correlations can be defined, under which instantaneous communication remains impossible. This raises the question: Why are the correlations achievable by quantum mechanics not maximal among those that preserve causality? We give a partial answer to this question by showing that slightly stronger correlations would result in a world in which communication complexity becomes trivial.