# Contextuality for preparations, transformations, and unsharp measurements

@article{Spekkens2005ContextualityFP, title={Contextuality for preparations, transformations, and unsharp measurements}, author={Robert W. Spekkens}, journal={Physical Review A}, year={2005}, volume={71}, pages={052108} }

The Bell-Kochen-Specker theorem establishes the impossibility of a noncontextual hidden variable model of quantum theory, or equivalently, that quantum theory is contextual. In this paper, an operational definition of contextuality is introduced which generalizes the standard notion in three ways: (i) it applies to arbitrary operational theories rather than just quantum theory, (ii) it applies to arbitrary experimental procedures rather than just sharp measurements, and (iii) it applies to a…

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