Public Quantum Communication and Superactivation

  title={Public Quantum Communication and Superactivation},
  author={Fernando G. S. L. Brand{\~a}o and Jonathan Oppenheim},
  journal={IEEE Transactions on Information Theory},
Is there a meaningful quantum counterpart to public communication? We argue that it is the symmetric-side channel. This connection is partially motivated by recent work, where it was found that if a sender would like to communicate a secret message to a receiver through an insecure quantum channel using a shared quantum state as a key, then the insecure quantum channel is only ever used to simulate a symmetric-side channel. Here, we further show, in complete analogy to the role of public… 
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