# 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} }

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.

## 148 Citations

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