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arXiv · 1002.4913

Quantum discord and local demons

Aharon Brodutch·Daniel R. Terno
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Abstract

Quantum discord was proposed as a measure of the "quantumness" of correlations. There are at least three different discord-like quantities, two of which determine the difference between the efficiencies of a Szilard's engine under different sets of restrictions. The three discord measures vanish simulataneosly. We introduce an easy way to test for zero discord, relate it to the Cerf-Adami conditional entropy and show that there is no relation between the discord and the local disitnguishability.

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Aharon Brodutch, Daniel R. Terno. 2010-06-09. Quantum discord and local demons. https://doi.org/10.1103/physreva.81.062103

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