发表机构
Institute for Quantum Computing; University of Waterloo（量子计算研究所; 滑铁卢大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
提出通用编译器，将满足最小条件的可信制备协议转为顺序设备无关协议，基于Rényi散度新刚性定理实现恒定速率并容忍恒定噪声，应用于不可克隆加密、复制保护和盲随机性扩展。
AI 中文摘要
我们给出一个通用编译器，用于将一大类具有可信状态制备的设备相关协议转化为顺序设备无关协议。为使我们的编译器适用，可信制备协议需满足某些最小条件：首先具有基于纠缠的实现，且该基于纠缠的实现对应于任何满足相当弱刚性条件的非局域游戏的最优策略。我们将通用编译器应用于给出不可克隆加密、点函数复制保护和盲随机性扩展的顺序设备无关协议。我们的技术贡献是一类基于Rényi散度的新刚性定理，具有灵活的密码学应用。它们使我们的编译器能够实现恒定速率（即制备的可信状态与设备使用次数之比），同时容忍每次设备使用时的恒定噪声水平。这克服了先前基于迹距离或保真度的刚性定理所面临的根本性缩放障碍。对于一般顺序情形，我们的证明基于Fawzi和Fawzi（2021）的锐散度链式法则，这足以获得恒定但相当低的速率。在设备不保留记忆的特殊情形下，我们通过推导一种修正的信道夹层散度的新次可加性性质来改进速率，这可能具有独立意义。最后，作为未来改进的前景，我们还证明了Brown、Fawzi和Fawzi（2021）的迭代均值散度的链式法则。
英文摘要
We give a generic compiler for turning a wide class of device-dependent protocols with trusted state preparation into sequential device-independent protocols. In order for our compiler to apply, the trusted-preparation protocol needs to satisfy certain minimal conditions: having an entanglement-based realization in the first place, and the entanglement-based realization corresponding to the optimal strategy of any non-local game that satisfies a fairly weak rigidity condition. We apply our generic compiler to give sequential device-independent protocols for uncloneable encryption, copy-protection of point functions, and blind randomness expansion. Our technical contribution is a new class of rigidity theorems based on Rényi divergences, with flexible cryptographic applications. They allow our compiler to achieve a constant rate (i.e., the ratio of trusted states prepared to device uses), while tolerating a constant level of noise per device usage. This overcomes a fundamental scaling obstacle faced by previous rigidity theorems for trace distance or fidelity. For the generic sequential case, our proof is based on the sharp-divergence chain rule by Fawzi and Fawzi (2021), which suffices for a constant but fairly low rate. In the special case when the devices retain no memory, we improve the rates by deriving a novel subadditivity property for a modified channel sandwiched divergence, which may be of independent interest. Finally, as a prospect for future improvements, we also prove a chain rule for the iterated-mean divergences from Brown, Fawzi and Fawzi (2021).
