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arXiv · 1112.0543

Uncertainty relations from simple entropic properties

Patrick J. Coles·Roger Colbeck·Li Yu·Michael Zwolak
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Abstract

Uncertainty relations provide constraints on how well the outcomes of incompatible measurements can be predicted, and, as well as being fundamental to our understanding of quantum theory, they have practical applications such as for cryptography and witnessing entanglement. Here we shed new light on the entropic form of these relations, showing that they follow from a few simple entropic properties, including the data processing inequality. We prove these relations without relying on the exact expression for the entropy, and hence show that a single technique applies to several entropic quantities, including the von Neumann entropy, min- and max-entropies and the Renyi entropies.

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Patrick J. Coles, Roger Colbeck, Li Yu, Michael Zwolak. 2012-04-16. Uncertainty relations from simple entropic properties. https://doi.org/10.1103/physrevlett.108.210405

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