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arXiv · 2501.03123

Crypto-nonlocality in arbitrarily dimensional systems

Jianqi Sheng·Dongkai Zhang·Lixiang Chen
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Abstract

According to Bell's theorem, any model based on local variables cannot reproduce certain quantum correlations. A critical question is whether one could devise an alternative framework, based on nonlocal variables, to reproduce quantum correlations while adhering to fundamental principles. Leggett proposed a nonlocal model, termed crypto-nonlocality, rooted in considerations of the reality of photon polarization, but this property restricted it to being bi-dimensional. In this Letter, we extend the crypto-nonlocal model to higher dimensions and develop a framework for constructing experimentally testable Leggett-type inequalities for arbitrary dimensions. Our investigation into models that yield specific predictions exceeding those of quantum mechanics is intriguing from an information-theoretic perspective and is expected to deepen our understanding of quantum correlations.

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Jianqi Sheng, Dongkai Zhang, Lixiang Chen. 2025-01-06. Crypto-nonlocality in arbitrarily dimensional systems. https://arxiv.org/abs/2501.03123

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