AI 中文总结
本文证明沿信道Φ的Choi-几乎独立同分布信道类的通用经典与量子容量等于Φ的容量，实现了对几乎独立同分布扰动的鲁棒通信。
AI 中文摘要
独立同分布（iid）范式描述了通过量子信道进行渐近通信时，信道Φ的n次使用由Φ^⊗n表示。由于精确的张量幂行为是一种理想化，我们探讨了对于沿Φ几乎独立同分布的信道序列，Φ的渐近容量是否仍然可达。我们考虑Choi-几乎独立同分布信道序列，其归一化Choi态沿Φ的归一化Choi态为Mazzola-Sutter-Renner（MSR）几乎独立同分布，缺陷参数r_n=o(n)。在Renner关于量子态的指数de Finetti定理中，几乎独立同分布态出现在近似混合中，并激发了MSR几乎独立同分布类。Choi-几乎独立同分布信道在配套论文中建立的量子信道指数de Finetti定理中扮演相应角色。本文证明了沿Φ的Choi-几乎独立同分布信道类的通用无辅助经典和量子容量等于信道Φ的容量。这里的通用性是在此类内：对于低于相关容量的每个速率，一个依赖于Φ和速率但不依赖于特定信道序列的码序列，对该类中的每个序列实现消失误差。
英文摘要
The independent and identically distributed (iid) paradigm for asymptotic communication through quantum channels describes $n$ uses of a channel $Φ$ by $Φ^{\otimes n}$. Since exact tensor-power behaviour is an idealization, we ask whether the asymptotic capacities of $Φ$ remain achievable for channel sequences that are almost-iid along $Φ$. We consider sequences of Choi-almost-iid channels whose normalized Choi states are Mazzola-Sutter-Renner (MSR) almost-iid along the normalized Choi state of $Φ$, with defect parameters $r_n=o(n)$. In Renner's exponential de Finetti theorem for quantum states, almost-iid states appear in the approximating mixture and motivate the MSR almost-iid class. Choi-almost-iid channels play the corresponding role in an exponential de Finetti theorem for quantum channels established in a companion paper. In this paper, we prove that the universal unassisted classical and quantum capacities of the class of Choi-almost-iid channels along $Φ$ equal those of the channel $Φ$. Here universality is within this class: for each rate below the relevant capacity, a code sequence depending on $Φ$ and the rate, but not on the particular channel sequence, achieves vanishing error for every sequence in the class.
Comments45 pages
