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arXiv · 1705.07918

The contextual fraction as a measure of contextuality

Samson Abramsky·Rui Soares Barbosa·Shane Mansfield
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Abstract

We consider the contextual fraction as a quantitative measure of contextuality of empirical models, i.e. tables of probabilities of measurement outcomes in an experimental scenario. It provides a general way to compare the degree of contextuality across measurement scenarios; it bears a precise relationship to violations of Bell inequalities; its value, and a witnessing inequality, can be computed using linear programming; it is monotone with respect to the "free" operations of a resource theory for contextuality; and it measures quantifiable advantages in informatic tasks, such as games and a form of measurement based quantum computing.

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Samson Abramsky, Rui Soares Barbosa, Shane Mansfield. 2017-05-22. The contextual fraction as a measure of contextuality. https://doi.org/10.1103/physrevlett.119.050504

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