On the Fidelity Robustness of CHSH--Bell Inequality via Filtered Random States

Antonio Mandarino; Giovanni Scala

doi:10.3390/e25010094

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arXiv · 2310.09231

On the Fidelity Robustness of CHSH--Bell Inequality via Filtered Random States

Antonio Mandarino·Giovanni Scala

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Abstract

The theorem developed by John Bell constituted the starting point of a revolution that translated a philosophical question about the nature of reality into the broad and intense field of research of the quantum information technologies. We focus on a system of two qubits prepared in a random, mixed state, and we study the typical behavior of their nonlocality via the CHSH--Bell inequality. Afterward, motivated by the necessity of accounting for inefficiency in the state preparation, we address to what extent states close enough to one with a high degree of nonclassicality can violate local realism with a previously chosen experimental setup.

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Antonio Mandarino, Giovanni Scala. 2023-10-13. On the Fidelity Robustness of CHSH--Bell Inequality via Filtered Random States. https://doi.org/10.3390/e25010094

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