Recoverability for optimized quantum f-divergences

  title={Recoverability for optimized quantum f-divergences},
  author={Li Gao and Mark M. Wilde},
  journal={Journal of Physics A: Mathematical and Theoretical},
  • Li GaoM. Wilde
  • Published 4 August 2020
  • Computer Science
  • Journal of Physics A: Mathematical and Theoretical
The optimized quantum f-divergences form a family of distinguishability measures that includes the quantum relative entropy and the sandwiched Rényi relative quasi-entropy as special cases. In this paper, we establish physically meaningful refinements of the data-processing inequality for the optimized f-divergence. In particular, the refinements state that the absolute difference between the optimized f-divergence and its channel-processed version is an upper bound on how well one can recover… 

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