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Comments on Hastings’ Additivity Counterexamples

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Abstract

Hastings [12] recently provided a proof of the existence of channels which violate the additivity conjecture for minimal output entropy. In this paper we present an expanded version of Hastings’ proof. In addition to a careful elucidation of the details of the proof, we also present bounds for the minimal dimensions needed to obtain a counterexample.

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Correspondence to Christopher King.

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Communicated by M.B. Ruskai

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Fukuda, M., King, C. & Moser, D.K. Comments on Hastings’ Additivity Counterexamples. Commun. Math. Phys. 296, 111–143 (2010). https://doi.org/10.1007/s00220-010-0996-9

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