Quantum Nonlocality of Arbitrary Dimensional Bipartite States

The main thread of chapter 4 introduces some of the major mysteries and interpretational issues of quantum mechanics (QM). These mysteries and issues include: quantum superposition, quantum nonlocality, Bell’s inequality, entanglement, delayed choice, the measurement problem, and the lack of counterfactual definiteness. All these mysteries and interpretational issues of QM result from dynamical explanation in the mechanical universe and are dispatched using the authors’ adynamical explanation in the block universe, called Relational Blockworld (RBW). A possible link between RBW and quantum information theory is provided. The metaphysical underpinnings of RBW, such as contextual emergence, spatiotemporal ontological contextuality, and adynamical global constraints, are provided in Philosophy of Physics for Chapter 4. That is also where RBW is situated with respect to retrocausal accounts and it is shown that RBW is a realist, psi-epistemic account of QM. All the relevant formalism for this chapter is provided in Foundational Physics for Chapter 4.

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Quantum postulate vs. quantum nonlocality: on the role of the Planck constant in Bell’s argument

Foundations of Physics ◽

10.1007/s10701-021-00430-3 ◽

2021 ◽

Vol 51 (1) ◽

Author(s):

Andrei Khrennikov

Keyword(s):

Quantum Nonlocality ◽

Quantum Mechanical ◽

Quantum Foundations ◽

Planck Constant ◽

Variable Model ◽

Basic Principles ◽

Fundamental Feature ◽

Hidden Variable ◽

Bell Model

AbstractWe present a quantum mechanical (QM) analysis of Bell’s approach to quantum foundations based on his hidden-variable model. We claim and try to justify that the Bell model contradicts to the Heinsenberg’s uncertainty and Bohr’s complementarity principles. The aim of this note is to point to the physical seed of the aforementioned principles. This is the Bohr’s quantum postulate: the existence of indivisible quantum of action given by the Planck constant h. By contradicting these basic principles of QM, Bell’s model implies rejection of this postulate as well. Thus, this hidden-variable model contradicts not only the QM-formalism, but also the fundamental feature of the quantum world discovered by Planck.

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Class of Bell-Clauser-Horne inequalities for testing quantum nonlocality

Physical Review A ◽

10.1103/physreva.103.062203 ◽

2021 ◽

Vol 103 (6) ◽

Author(s):

Chen Qian ◽

Yang-Guang Yang ◽

Qun Wang ◽

Cong-Feng Qiao

Keyword(s):

Quantum Nonlocality

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Experimental observation of quantum nonlocality in general networks with different topologies

Fundamental Research ◽

10.1016/j.fmre.2020.11.002 ◽

2021 ◽

Vol 1 (1) ◽

pp. 22-26

Author(s):

Chao Zhang ◽

Huan Cao ◽

Yun-Feng Huang ◽

Bi-Heng Liu ◽

Chuan-Feng Li ◽

...

Keyword(s):

Experimental Observation ◽

Quantum Nonlocality ◽

General Networks

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Mutually unbiased bases and symmetric informationally complete measurements in Bell experiments

Science Advances ◽

10.1126/sciadv.abc3847 ◽

2021 ◽

Vol 7 (7) ◽

pp. eabc3847

Author(s):

Armin Tavakoli ◽

Máté Farkas ◽

Denis Rosset ◽

Jean-Daniel Bancal ◽

Jedrzej Kaniewski

Keyword(s):

Quantum Key Distribution ◽

Random Number ◽

Random Number Generation ◽

Bell Inequalities ◽

Extremal Point ◽

Optimal Rate ◽

Quantum Nonlocality ◽

Space Structures ◽

Mutually Unbiased Bases ◽

Practical Relevance

Mutually unbiased bases (MUBs) and symmetric informationally complete projectors (SICs) are crucial to many conceptual and practical aspects of quantum theory. Here, we develop their role in quantum nonlocality by (i) introducing families of Bell inequalities that are maximally violated by d-dimensional MUBs and SICs, respectively, (ii) proving device-independent certification of natural operational notions of MUBs and SICs, and (iii) using MUBs and SICs to develop optimal-rate and nearly optimal-rate protocols for device-independent quantum key distribution and device-independent quantum random number generation, respectively. Moreover, we also present the first example of an extremal point of the quantum set of correlations that admits physically inequivalent quantum realizations. Our results elaborately demonstrate the foundational and practical relevance of the two most important discrete Hilbert space structures to the field of quantum nonlocality.

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Demonstrating the power of quantum computers, certification of highly entangled measurements and scalable quantum nonlocality

npj Quantum Information ◽

10.1038/s41534-021-00450-x ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Elisa Bäumer ◽

Nicolas Gisin ◽

Armin Tavakoli

Keyword(s):

Quantum Computer ◽

Outcome Measurement ◽

Bell State ◽

Bell Inequalities ◽

Quantum Correlations ◽

Entanglement Swapping ◽

Quantum Nonlocality ◽

Quantum Computers ◽

Classical Models ◽

Quantum Phenomena

AbstractIncreasingly sophisticated quantum computers motivate the exploration of their abilities in certifying genuine quantum phenomena. Here, we demonstrate the power of state-of-the-art IBM quantum computers in correlation experiments inspired by quantum networks. Our experiments feature up to 12 qubits and require the implementation of paradigmatic Bell-State Measurements for scalable entanglement-swapping. First, we demonstrate quantum correlations that defy classical models in up to nine-qubit systems while only assuming that the quantum computer operates on qubits. Harvesting these quantum advantages, we are able to certify 82 basis elements as entangled in a 512-outcome measurement. Then, we relax the qubit assumption and consider quantum nonlocality in a scenario with multiple independent entangled states arranged in a star configuration. We report quantum violations of source-independent Bell inequalities for up to ten qubits. Our results demonstrate the ability of quantum computers to outperform classical limitations and certify scalable entangled measurements.

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