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arXiv · 0807.2668

Mixing doubly stochastic quantum channels with the completely depolarizing channel

John Watrous
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Abstract

It is proved that every doubly stochastic quantum channel that is properly averaged with the completely depolarizing channel can be written as a convex combination of unitary channels. As a consequence, we find that the collection of channels expressible as convex combinations of unitary channels has non-zero Borel measure within the space of doubly stochastic channels.

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John Watrous. 2008-07-16. Mixing doubly stochastic quantum channels with the completely depolarizing channel. https://arxiv.org/abs/0807.2668

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