Remark on the additivity conjecture for the quantum depolarizing channel

G. G. Amosov

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Remark on the additivity conjecture for the quantum depolarizing channel

G. G. Amosov

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Abstract

We consider bistochastic quantum channels generated by unitary representations of the discret group. The proof of the additivity conjecture for the quantum depolarizing channel $Φ$ based on the decreasing property of the relative entropy is given. We show that the additivity conjecture is true for the channel $Ξ=Ψ\circ Φ$, where $Ψ$ is the phase damping.

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G. G. Amosov. 2005-09-11. Remark on the additivity conjecture for the quantum depolarizing channel. https://arxiv.org/abs/quant-ph/0408004

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