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arXiv · 0907.4494

State-independent quantum contextuality with single photons

Elias Amselem·Magnus Radmark·Mohamed Bourennane·Adan Cabello
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Abstract

We present an experimental state-independent violation of an inequality for noncontextual theories on single particles. We show that 20 different single-photon states violate an inequality which involves correlations between results of sequential compatible measurements by at least 419 standard deviations. Our results show that, for any physical system, even for a single system, and independent of its state, there is a universal set of tests whose results do not admit a noncontextual interpretation. This sheds new light on the role of quantum mechanics in quantum information processing.

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Elias Amselem, Magnus Radmark, Mohamed Bourennane, Adan Cabello. 2009-10-18. State-independent quantum contextuality with single photons. https://doi.org/10.1103/physrevlett.103.160405

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