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arXiv · 1506.04178

Robust preparation noncontextuality inequalities in the simplest scenario

Matthew F. Pusey
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Abstract

Contextuality is the leading notion of nonclassicality for a single system. However, an experimental demonstration requires finding procedures that are operationally equivalent, which might seem impossible to achieve exactly. Here I focus on the simplest non-trivial case, four preparations and two tomographically complete binary measurements. Exploiting a subtle connection to the CHSH scenario gives eight non-linear inequalities which are together necessary and sufficient for the experimental statistics to admit a preparation noncontextual model in such a scenario. No fixed operational equivalences are required, removing a key difficulty with experimental tests of older preparation noncontextuality inequalities.

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Matthew F. Pusey. 2015-06-12. Robust preparation noncontextuality inequalities in the simplest scenario. https://doi.org/10.1103/physreva.98.022112

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