aiqbench analysis
This paper extends Leggett-type nonlocal realistic models to arbitrary N-partite systems, establishing rigorous inequalities that distinguish quantum predictions from classical theories in multipartite scenarios. By demonstrating specific violations using Greenberger-Horne-Zeilinger (GHZ) states, the work provides a clear experimental framework for testing the limits of nonlocal realism beyond simple bipartite setups. The correction of previous bounds to a fundamental double inequality strengthens the theoretical foundation for future quantum verification experiments.
Leggett-type inequalities for testing nonlocal realism in multipartite systems
arXiv:2108.03665v2 Announce Type: replace Abstract: Nonlocal realism represents the last classical cornerstone in conflict with quantum theory, and has been shown to be largely untenable in bipartite systems [Nature 446, 871 (2007); Nature Physics 4, 681 (2008)]. We extend the Leggett-type nonlocal realistic model to arbitrary N-partite systems with polarizer settings, and derive rigorous inequalities that distinguish quantum predictions from nonlocal realistic theories. The derivation yields a fundamental double inequality that is universally valid, from which the Leggett-type bounds follow under specific measurement settings. As an illustration, we demonstrate quantum violations of these inequalities for Greenberger-Horne-Zeilinger (GHZ) states, with maximal violation 2(\sqrt{5}+1). Our results show that nonlocal realism in multipartite systems is experimentally testable.
Abstract:Nonlocal realism represents the last classical cornerstone in conflict with quantum theory, and has been shown to be largely untenable in bipartite systems [Nature 446, 871 (2007); Nature Physics 4, 681 (2008)]. We extend the Leggett-type nonlocal realistic model to arbitrary N-partite systems with polarizer settings, and derive rigorous inequalities that distinguish quantum predictions from nonlocal realistic theories. The derivation yields a fundamental double inequality that is universally valid, from which the Leggett-type bounds follow under specific measurement settings. As an illustration, we demonstrate quantum violations of these inequalities for Greenberger-Horne-Zeilinger (GHZ) states, with maximal violation 2(\sqrt{5}+1). Our results show that nonlocal realism in multipartite systems is experimentally testable.
This is a major revision of the previous version (v1). The derivation has been corrected by replacing the min/max bound with a rigorous double inequality, and the supplementary material has been significantly expanded and clarified. All main results, including the GHZ violation 2(\sqrt{5}+1), remain unchanged. 25 pages, 4 figures
arXiv:2108.03665 [quant-ph]
(or arXiv:2108.03665v2 [quant-ph] for this version)
Full text under the publisher's open licence · 166 words
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