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Related papers: Hardy's nonlocality for generalized n-particle GHZ…

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Systems of four nonbinary particles, each having three or more internal states, exhibit maximally entangled states that are inaccessible to four qubits. This breaks the pattern of two- and three-particle systems, in which the existing graph…

Quantum Physics · Physics 2015-06-23 Mario Gaeta , Andrei Klimov , Jay Lawrence

The exploration of entanglement and Bell non-locality among multi-particle quantum systems offers a profound avenue for testing and understanding the limits of quantum mechanics and local real hidden variable theories. In this work, we…

Quantum Physics · Physics 2025-10-23 Paweł Horodecki , Kazuki Sakurai , Abhyoudai S. Shaleena , Michael Spannowsky

We in this Letter derive analytic formulas of Bell correlations in terms of quantum probability statistics under the assumption of measuring outcome-independence. For a spin-1/2 singlet state we find analytically that the violations of…

Quantum Physics · Physics 2013-04-09 Zhigang Song , J. -Q. Liang , L. -F. Wei

The Hardy test of nonlocality can be seen as a particular case of the Bell tests based on the Clauser-Horne (CH) inequality. Here we stress this connection when we analyze the relation between the CH-inequality violation, its threshold…

Quantum Physics · Physics 2015-06-03 G. Lima , E. B. Inostroza , R. O. Vianna , J. -Å. Larsson , C. Saavedra

We consider the transformation of multisystem entangled states by local quantum operations and classical communication. We show that, for any reversible transformation, the relative entropy of entanglement for two parties must remain…

Quantum Physics · Physics 2007-05-23 N. Linden , S. Popescu , B. Schumacher , M. Westmoreland

We present a Bell-type inequality for four-qubit systems. Using the inequality we investigate quantum nonlocality of a generic family of states $\left|G_{abcd}\right >$ [Phys. Rev. A 65, 052112 (2002)] and several canonical four-qubit…

Quantum Physics · Physics 2017-06-07 Dong Ding , Fengli Yan , Ting Gao

Non-classical quantum correlations underpin both the foundations of quantum mechanics and modern quantum technologies. Among them, Bell nonlocality is a central example. For bipartite Bell inequalities, nonlocal correlations obey strict…

Quantum Physics · Physics 2026-05-13 Gerard Anglès Munné , Paweł Cieśliński , Jan Wójcik , Wiesław Laskowski

It remains an open question whether every pure multipartite state that is genuinely entangled is also genuinely nonlocal. Recently, a new general construction of Bell inequalities allowing the detection of genuine multipartite nonlocality…

Quantum Physics · Physics 2024-09-23 Ignacy Stachura , Owidiusz Makuta , Remigiusz Augusiak

In this note, we study Cabello's nonlocality argument (CNA) for three-qubit systems configured in the generalized GHZ state. For this class of states, we show that CNA runs for almost all entangled ones, and that the maximum probability of…

Quantum Physics · Physics 2016-09-27 José L. Cereceda

We derive a new inequality that is necessary and sufficient to show EPR-steering in a scenario employing only correlations between two arbitrary dichotomic measurements on each party. Thus the inequality is a complete steering analogy of…

Quantum Physics · Physics 2017-12-19 Parth Girdhar , Eric G. Cavalcanti

We present, at the gedanken level, a possibly novel non-statistical demonstration of nonlocality for two maximally entangled particles. The argument requires only two alternative experimental contexts, only one and the same single-particle…

Quantum Physics · Physics 2007-05-23 Demetrios Kalamidas

Analyzing the properties of entanglement in many-particle spin-1/2 systems is generally difficult because the system's Hilbert space grows exponentially with the number of constituent particles, $N$. Fortunately, it is still possible to…

Quantum Physics · Physics 2007-05-23 John K. Stockton , JM Geremia , Andrew C. Doherty , Hideo Mabuchi

For a multipartite quantum state, the maximal violation of all Bell inequalities constitutes a measure of its nonlocality [Loubenets, J. Math. Phys. 53, 022201 (2012)]. In the present article, for the maximal violation of Bell inequalities…

Quantum Physics · Physics 2022-07-06 Elena R. Loubenets , Min Namkung

When three or more particles are considered, quantum correlations can be stronger than the correlations generated by so-called hybrid local hidden variable models, where some of the particles are considered as a single block inside which…

Quantum Physics · Physics 2023-02-13 Fabian Bernards , Otfried Gühne

The familiar Greenberger-Horne-Zeilinger (GHZ) states can be rewritten by entangling the Bell states for two qubits with a state of the third qubit, which is dubbed entangled entanglement. We show that in this way we obtain all 8…

Quantum Physics · Physics 2015-10-06 Gabriele Uchida , Reinhold A. Bertlmann , Beatrix C. Hiesmayr

The nonlocal properties of the W states are investigated under particle loss. By removing all but two particles from an $N$-qubit W state, the resulting two-qubit state is still entangled. Hence, the W state has high persistency of…

Quantum Physics · Physics 2016-05-20 Péter Diviánszky , Réka Trencsényi , Erika Bene , Tamás Vértesi

We derive tight quadratic inequalities for all kinds of hybrid separable-inseparable $n$-particle density operators on an arbitrary dimensional space. This methodology enables us to truly derive a tight quadratic inequality as tests for…

Quantum Physics · Physics 2009-11-07 Koji Nagata , Masato Koashi , Nobuyuki Imoto

We determine the complete set of generalized spin squeezing inequalities. These are entanglement criteria that can be used for the experimental detection of entanglement in a system of spin-1/2 particles in which the spins cannot be…

Quantum Physics · Physics 2011-11-09 Geza Toth , Christian Knapp , Otfried Gühne , Hans J. Briegel

Multipartite nonlocality is of great fundamental interest and constitutes a useful resource for many quantum information protocols. However, demonstrating it in practice, by violating a Bell inequality, can be difficult. In particular,…

Quantum Physics · Physics 2015-06-25 Celal Furkan Senel , Thomas Lawson , Marc Kaplan , Damian Markham , Eleni Diamanti

We give a analytic quantitative relation between Hardy's non-locality and Bell operator. We find that Hardy's non-locality is a sufficient condition for violation of Bell inequality, the upper bound of Hardy's non-locality allowed by…

Quantum Physics · Physics 2015-05-19 Yang Xiang