We show that the approximate quasi-orthogonality of two operator algebras is equivalent to the algebras being approximately private relative to their conditional expectation quantum channels. Our analysis is based on a characterization of the measure of orthogonality in terms of Choi matrices and Kraus operators for completely positive maps. We present examples drawn from different areas of quantum information.

中文翻译：

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算子代数的近似准正交性和相对量子保密性

我们表明，两个算子代数的近似准正交性等同于相对于它们的条件期望量子通道近似为私有的代数。我们的分析基于对完全正图的Choi矩阵和Kraus算子的正交性度量的表征。我们提供了来自量子信息不同领域的例子。