On Hastings' Counterexamples to the Minimum Output Entropy Additivity Conjecture

@article{Brando2010OnHC,
  title={On Hastings' Counterexamples to the Minimum Output Entropy Additivity Conjecture},
  author={Fernando G. S. L. Brand{\~a}o and Michal Horodecki},
  journal={Open Syst. Inf. Dyn.},
  year={2010},
  volume={17},
  pages={31-52}
}
Hastings recently reported a randomized construction of channels violating the minimum output entropy additivity conjecture. Here we revisit his argument, presenting a simplified proof. In particular, we do not resort to the exact probability distribution of the Schmidt coefficients of a random bipartite pure state, as in the original proof, but rather derive the necessary large deviation bounds by a concentration of measure argument. Furthermore, we prove non-additivity for the overwhelming… 
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