We analyze the information an attacker can obtain on the numbers generated by a user by measurements on a subsystem of a system consisting of two entangled two-level systems. The attacker and the user make measurements on their respective subsystems, only. Already the knowledge of the density matrix of the subsystem of the user completely determines the upper bound on the information accessible to the attacker. We compare and contrast this information to the appropriate bounds provided by quantum state discrimination.

中文翻译：

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估计量子随机数的隐私

我们通过对由两个纠缠的两级系统组成的系统的子系统的测量来分析攻击者可以获得的关于用户生成的数字的信息。攻击者和用户仅对各自的子系统进行测量。用户子系统的密度矩阵的知识已经完全确定了攻击者可以访问的信息的上限。我们将此信息与量子状态鉴别提供的适当界限进行比较和对比。