The Einstein–Podolsky–Rosen Paradox, Bell’s Theorem and Nonlocality

Abstract Bell’s theorem proves that quantum theory is inconsistent with local physical models. It has propelled research in the foundations of quantum theory and quantum information science. As a fundamental feature of quantum theory, it impacts predictions far beyond the traditional scenario of the Einstein-Podolsky-Rosen paradox. In the last decade, the investigation of nonlocality has moved beyond Bell’s theorem to consider more sophisticated experiments that involve several independent sources that distribute shares of physical systems among many parties in a network. Network scenarios, and the nonlocal correlations that they give rise to, lead to phenomena that have no counterpart in traditional Bell experiments, thus presenting a formidable conceptual and practical challenge. This review discusses the main concepts, methods, results and future challenges in the emerging topic of Bell nonlocality in networks.

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The photon identification loophole in EPRB experiments: computer models with single-wing selection

Open Physics ◽

10.1515/phys-2017-0085 ◽

2017 ◽

Vol 15 (1) ◽

pp. 713-733 ◽

Cited By ~ 3

Author(s):

Hans De Raedt ◽

Kristel Michielsen ◽

Karl Hess

Keyword(s):

Laboratory Experiments ◽

Thought Experiment ◽

Discrete Event ◽

Theoretical Description ◽

Bell’S Theorem ◽

Quantum Model ◽

Bell's Theorem ◽

Event Simulation ◽

Einstein Podolsky Rosen ◽

Local Station

AbstractRecent Einstein-Podolsky-Rosen-Bohm experiments [M. Giustinaet al. Phys. Rev. Lett. 115, 250401 (2015); L. K. Shalmet al. Phys. Rev. Lett. 115, 250402 (2015)] that claim to be loophole free are scrutinized. The combination of a digital computer and discrete-event simulation is used to construct a minimal but faithful model of the most perfected realization of these laboratory experiments. In contrast to prior simulations, all photon selections are strictly made, as they are in the actual experiments, at the local station and no other “post-selection” is involved. The simulation results demonstrate that a manifestly non-quantum model that identifies photons in the same local manner as in these experiments can produce correlations that are in excellent agreement with those of the quantum theoretical description of the corresponding thought experiment, in conflict with Bell’s theorem which states that this is impossible. The failure of Bell’s theorem is possible because of our recognition of the photon identification loophole. Such identification measurement-procedures are necessarily included in all actual experiments but are not included in the theory of Bell and his followers.

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Quantum Computation and Arrows of Time

Entropy ◽

10.3390/e23010049 ◽

2020 ◽

Vol 23 (1) ◽

pp. 49

Author(s):

Nathan Argaman

Keyword(s):

Quantum Computation ◽

Quantum Physics ◽

Bell’S Theorem ◽

Arrow Of Time ◽

Bell's Theorem ◽

Classical Domain ◽

Further Development

Quantum physics is surprising in many ways. One surprise is the threat to locality implied by Bell’s Theorem. Another surprise is the capacity of quantum computation, which poses a threat to the complexity-theoretic Church-Turing thesis. In both cases, the surprise may be due to taking for granted a strict arrow-of-time assumption whose applicability may be limited to the classical domain. This possibility has been noted repeatedly in the context of Bell’s Theorem. The argument concerning quantum computation is described here. Further development of models which violate this strong arrow-of-time assumption, replacing it by a weaker arrow which is yet to be identified, is called for.

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