Quantum communication channels suffer from various noises, which are mathematically modeled by error super-operators. To combat these errors, it is necessary to design recovery super-operators. We aim to construct the optimal recovery that maximizes the minimum fidelity through the noisy channel. It is typically a MAX–MIN problem, out of the scope of convex optimization. Compared to existing methods, our method is exact and complete by a reduction to quantifier elimination over real closed fields in a fragment of two alternative quantifier blocks. Finally, the complexity is shown to be in EXP.

中文翻译：

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使用量词消除的最佳量子纠错程序

量子通信通道会遭受各种噪声的影响，而这些噪声是由错误超级算子进行数学建模的。为了解决这些错误，有必要设计恢复超级操作员。我们的目标是构建最佳恢复，以通过噪声通道最大化最小保真度。它通常是一个MAX–MIN问题，超出了凸优化的范围。与现有方法相比，我们的方法精确而完整，因为它减少了两个替代量词块片段中的实际封闭域的量词消除。最后，复杂度显示为EXP。