论文标题
部分可观测时空混沌系统的无模型预测
Security of quantum key distribution from generalised entropy accumulation
论文作者
论文摘要
量子密钥分布（QKD）的目的是建立由不安全量子通道连接的两个方之间的安全密钥。要在实践中使用QKD协议，必须证明有限的大小密钥是安全的：无论对手的攻击如何，它们都无法获得有关密钥的有用信息。一个更简单的任务是证明对集体攻击的安全性，在这种攻击中，假定对手在每回合中行为相同和独立。在这项工作中，我们为一般QKD协议提供了一个正式的框架，并表明，对于可以在此框架中表达的任何协议，防止一般攻击的安全性降低了针对集体攻击的安全性，这反过来又减少了数值计算。我们的证明依赖于最近开发的称为广义熵积累的信息理论工具，并且可以直接处理通用的准备和衡量协议而无需切换到基于纠缠的版本。
The goal of quantum key distribution (QKD) is to establish a secure key between two parties connected by an insecure quantum channel. To use a QKD protocol in practice, one has to prove that a finite size key is secure against general attacks: no matter the adversary's attack, they cannot gain useful information about the key. A much simpler task is to prove security against collective attacks, where the adversary is assumed to behave identically and independently in each round. In this work, we provide a formal framework for general QKD protocols and show that for any protocol that can be expressed in this framework, security against general attacks reduces to security against collective attacks, which in turn reduces to a numerical computation. Our proof relies on a recently developed information-theoretic tool called generalised entropy accumulation and can handle generic prepare-and-measure protocols directly without switching to an entanglement-based version.
