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arXiv · 2309.12868

Indirect Indication of the KCBS-Type Quantum Contextuality by the CHSH-Bell Test

Firat Diker·Antonio Mandarino
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Abstract

In this work, we show that the well-known Bell inequality in the Clauser-Horne-Shimony-Holt (CHSH) formulation serves not only as a non-locality test but also as a tool to prove KCBS-type contextuality. For this purpose, we investigate the symmetric family of two-qubit states that can be mapped to qutrit states (three-level quantum states) and show that they exhibit a contextual description, as evidenced by the KCBS-type inequality. Later, we apply the CHSH test to them and find a new non-contextuality bound for this test. This shows that the CHSH inequality can be modified to serve as a KCBS-type contextuality test by changing the limit. Also, the number of measurements required is four, fewer than the KCBS test's five. We discuss the new bound concerning the monogamy problem.

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Firat Diker, Antonio Mandarino. 2023-09-22. Indirect Indication of the KCBS-Type Quantum Contextuality by the CHSH-Bell Test. https://arxiv.org/abs/2309.12868

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