正算子值测度与单位完全正映射的 C*-极值点
算子代数
2021-12-01 v2
摘要
我们研究可测空间上归一化正算子值测度(POVM)的量子()凸结构。特别地,可见与经典凸性下的极值点不同,可数空间(尤其是有限集)上归一化 POVM 的 -极值点总是谱测度(归一化投影值测度)。更一般地,我们证明了原子 -极值点是谱的。我们还证明了 POVM 的一个 Krein-Milman 型定理。作为一个应用,我们证明了任意具有可数谱(特别是 )的交换单位 -代数上的映射,在 unit 完全正映射集合中是 -极值的,当且仅当它是一个单位 -同态。
引用
@article{arxiv.2006.07076,
title = {$C^*$-extreme points of positive operator valued measures and unital completely positive maps},
author = {Tathagata Banerjee and B V Rajarama Bhat and Manish Kumar},
journal= {arXiv preprint arXiv:2006.07076},
year = {2021}
}
备注
36 pages; Some comments on a result in Holevo's book 'Statistical Structure of Quantum Theory' included after Corollary 2.10; A summary of our main results provided in the last Section; Some Remarks (2.3, 2.7, 4.6) added for clarification purposes; Several typos corrected; To appear in Communications in Mathematical Physics