# Recoverability for optimized quantum f-divergences

@article{Gao2021RecoverabilityFO, title={Recoverability for optimized quantum f-divergences}, author={Li Gao and Mark M. Wilde}, journal={Journal of Physics A: Mathematical and Theoretical}, year={2021}, volume={54} }

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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