Acín A, Cirac J I, Masanes Ll
Institut de Ciències Fotòniques, Jordi Girona 29, Edifici Nexus II, 08034 Barcelona, Spain.
Phys Rev Lett. 2004 Mar 12;92(10):107903. doi: 10.1103/PhysRevLett.92.107903.
We prove the conjectured existence of bound information, a classical analog of bound entanglement, in the multipartite scenario. We give examples of tripartite probability distributions from which it is impossible to extract any kind of secret key, even in the asymptotic regime, although they cannot be created by local operations and public communication. Moreover, we show that bound information can be activated: three honest parties can distill a common secret key from different distributions having bound information. Our results demonstrate that quantum information theory can provide useful insight for solving open problems in classical information theory.
我们证明了在多方情形下束缚信息（一种束缚纠缠的经典类似物）的推测存在性。我们给出了三方概率分布的例子，从这些分布中即使在渐近情形下也不可能提取任何类型的秘密密钥，尽管它们不能通过局部操作和公共通信来创建。此外，我们表明束缚信息可以被激活：三个诚实的参与方可以从具有束缚信息的不同分布中提取出一个公共秘密密钥。我们的结果表明量子信息理论可以为解决经典信息理论中的开放问题提供有用的见解。
