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arXiv · 1206.0231

The problem with the geometric discord

Marco Piani
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Abstract

We argue that the geometric discord introduced in [B. Dakic, V. Vedral, and C. Brukner, Phys. Rev. Lett. 105, 190502 (2010)] is not a good measure for the quantumness of correlations, as it can increase even under trivial local reversible operations of the party whose classicality/non-classicality is not tested. On the other hand it is known that the standard, mutual-information based discord does not suffer this problem; a simplified proof of such a fact is given.

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Marco Piani. 2012-06-01. The problem with the geometric discord. https://doi.org/10.1103/physreva.86.034101

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