# A counterexample to additivity of minimum output entropy

@article{Hastings2008ACT,
title={A counterexample to additivity of minimum output entropy},
author={Matthew B. Hastings},
journal={Physical Review Letters},
year={2008}
}
• M. Hastings
• Published 23 September 2008
• Mathematics
• Physical Review Letters
We present a random construction of a pair of channels which gives, with non-zero probability for sufficiently large dimensions, a counterexample to the minimum output entropy conjecture. As shown by Shor, this implies a violation of the additivity conjecture for the classical capacity of quantum channels. The violation of the minimum output entropy conjecture is relatively small.
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