量子比特承诺协议中的隐蔽度和绑定度
Degrees of concealment and bindingness in quantum bit commitment protocols
摘要：
虽然比特承诺协议不可能既任意隐藏又任意绑定，但它既部分隐藏又部分绑定是可能的。这意味着Bob不能在公开阶段开始之前找到关于提交的位的所有信息，而Alice不能通过在提交阶段结束之后采取的行动来公开她想要的任何位。我们确定上界的隐藏和绑定度，可以同时实现在任何位承诺协议，虽然它是未知的，这些是否可以饱和。然而，我们确定这些数量的最大值在一个有限的类位承诺协议，即那些在承诺阶段发挥作用的所有系统提供的爱丽丝。我们表明，这些最大值可以实现使用一个协议，需要爱丽丝准备一对系统在纠缠态，提交一对鲍勃在承诺阶段，和其他在揭幕阶段。最后，我们确定的形式之间存在的折衷的程度的隐蔽性和绑定的程度给出各种假设的纯度和维数的状态中使用的协议。
英文摘要：
Although it is impossible for a bit commitment protocol to be both arbitrarily concealing and arbitrarily binding, it is possible for it to be both partially concealing and partially binding. This means that Bob cannot, prior to the beginning of the unveiling phase, find out everything about the bit committed, and Alice cannot, through actions taken after the end of the commitment phase, unveil whatever bit she desires. We determine upper bounds on the degrees of concealment and bindingness that can be achieved simultaneously in any bit commitment protocol, although it is unknown whether these can be saturated. We do, however, determine the maxima of these quantities in a restricted class of bit commitment protocols, namely those wherein all the systems that play a role in the commitment phase are supplied by Alice. We show that these maxima can be achieved using a protocol that requires Alice to prepare a pair of systems in an entangled state, submit one of the pair to Bob at the commitment phase, and the other at the unveiling phase. Finally, we determine the form of the trade-off that exists between the degree of concealment and the degree of bindingness given various assumptions about the purity and dimensionality of the states used in the protocol.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
