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arXiv · 2505.11362

Channel coding against quantum jammers via minimax

Michael X. Cao·Yongsheng Yao·Mario Berta
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Abstract

We introduce a minimax approach for characterizing the capacities of fully quantum arbitrarily varying channels (FQAVCs) under different shared resource models. In contrast to previous methods, our technique avoids de Finetti-type reductions, providing a more streamlined proof without dependency on the dimension of the jamming system. Consequently, we show that the entanglement-assisted and shared-randomness-assisted capacities of FQAVCs match those of the corresponding compound channels, even in the presence of general quantum adversaries.

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Michael X. Cao, Yongsheng Yao, Mario Berta. 2025-05-16. Channel coding against quantum jammers via minimax. https://arxiv.org/abs/2505.11362

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