We present two experiments testing the hypothesis of noncontextual hidden variables (NCHV's). The first one is based on observation of two-photon pseudo-Greenberger-Horne-Zeilinger correlations, with two of the originally three particles mimicked by the polarization degree of freedom and the spatial degree of freedom of a single photon. The second one, a single-photon experiment, utilizes the same trick to emulate two particle correlations, and is an "event ready" test of a Bell-like inequality, derived from the noncontextuality assumption. Modulo fair sampling, the data falsify NCHV's.
Cite
@article{arxiv.quant-ph/0009061,
title = {Experiments towards Falsification of Noncontextual Hidden Variable Theories},
author = {Markus Michler and Harald Weinfurter and Marek Zukowski},
journal= {arXiv preprint arXiv:quant-ph/0009061},
year = {2009}
}