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Related papers: Quantum Counterfactuals and Locality

200 papers

Recently, Gallego et.al. [Phys. Rev. Lett 107, 210403 (2011)] proved that any future information principle aiming at distinguishing between quantum and post-quantum correlation must be intrinsically multipartite in nature. We establish…

Quantum Physics · Physics 2013-01-18 Subhadipa Das , Manik Banik , Ashutosh Rai , MD Rajjak Gazi , Samir Kunkri

It is univocally anticipated that in a theory of quantum gravity, there exist quantum superpositions of semiclassical states of spacetime geometry. Such states could arise for example, from a source mass in a superposition of spatial…

General Relativity and Quantum Cosmology · Physics 2025-01-20 Joshua Foo , Robert B. Mann , Magdalena Zych

For a special stochastic realistic model in certain spin-correlation experiments and without imposing the locality condition, an inequality is found. Then, it is shown that quantum theory is able (is possible) to violate this inequality.…

Quantum Physics · Physics 2007-05-23 Habibollah Razmi

William Unruh has suggested (quant-ph/9710032) that a certain counterfactual statement in my recent nonlocality proof should be re-interpreted in a way that would block the proof. I give reason's why that statement should not be…

Quantum Physics · Physics 2007-05-23 Henry P. Stapp

In this paper we provide a simple proof of the fact that for a system of two spin-1/2 particles, and for a choice of observables, there is a unique state which shows Hardy-type nonlocality. Moreover, an explicit expression for the…

Quantum Physics · Physics 2007-05-23 Jose L. Cereceda

It is demonstrated that hidden variables of a certain type follow logically from a certain local causality requirement (``Bell Locality'') and the empirically well-supported predictions of quantum theory for the standard EPR-Bell setup. The…

Quantum Physics · Physics 2015-06-26 Travis Norsen

We show that the presented real-number quantum theories, compatible with the independent source assumption, require the inclusion of a nonlocal map. This means that if the independent source assumption holds, in these models, complex-number…

Quantum Physics · Physics 2026-04-14 Tianfeng Feng , Changliang Ren , Vlatko Vedral

The Weltanschauung emerging from quantum theory clashes profoundly with our classical concepts. Quantum characteristics like superposition, entanglement, wave-particle duality, nonlocality, contextuality are difficult to reconcile with our…

Quantum Physics · Physics 2015-06-16 Radu Ionicioiu

In quantum logical terms, Hardy-type arguments can be uniformly presented and extended as collections of intertwined contexts and their observables. If interpreted classically those structures serve as graph-theoretic "gadgets" that enforce…

Quantum Physics · Physics 2023-06-29 Karl Svozil

What violations of Bell inequalities teach us is that the world is quantum mechanical, i.e., nonclassical. Assertions that they imply the world is nonlocal arise from ignoring differences between quantum and classical physics.

Quantum Physics · Physics 2013-04-17 Robert B. Griffiths

It is known that "quantum non locality", leading to the violation of Bell's inequality and more generally of classical local realism, can be attributed to the conjunction of two properties, that we call here elementary locality and…

Quantum Physics · Physics 2022-01-04 Philippe Grangier

An alternative proof for existence of ``quantum nonlocality without entanglement'', i.e. existence of variables with product-state eigenstates which cannot be measured locally, is presented. A simple``nonlocal'' variable for the case of…

Quantum Physics · Physics 2009-11-07 Berry Groisman , Lev Vaidman

Recent work has argued that the concepts of entanglement and nonlocality must be taken seriously even in systems consisting of only a single particle. These treatments, however, are nonrelativistic and, if single particle entanglement is…

Quantum Physics · Physics 2015-05-13 Jacob Dunningham , Vlatko Vedral

The empirical proof of Bell inequality violations was a landmark moment for research into quantum foundations. It commits us to a universe without strict relativistic locality or requires that we escape through a potential loophole like…

Quantum Physics · Physics 2026-05-29 Geoff Beck

The interpretative principle proposed by Bub in 1211.3062v1 [quant-ph] is justified only for all practical purposes (Bell's "FAPP trap"). An alternative interpretative principle is proposed. It brings to light those features of the quantum…

Quantum Physics · Physics 2012-12-18 Ulrich Mohrhoff

As with a Bell inequality, Hardy's paradox manifests a contradiction between the prediction given by quantum theory and local-hidden variable theories. In this work, we give two generalizations of Hardy's arguments for manifesting such a…

Quantum Physics · Physics 2024-04-10 Kai-Siang Chen , Shiladitya Mal , Gelo Noel M. Tabia , Yeong-Cherng Liang

The results of local measurements on some composite quantum systems cannot be reproduced classically. This impossibility, known as quantum nonlocality, represents a milestone in the foundations of quantum theory. Quantum nonlocality is also…

Quantum Physics · Physics 2015-05-20 D. Cavalcanti , M. L. Almeida , V. Scarani , A. Acin

Quantum nonlocality is arguably among the most counter-intuitive phenomena predicted by quantum theory. In recent years, the development of an abstract theory of nonlocality has brought a much deeper understanding of the subject. In…

We present a logical type of proof of contextuality for a two-qubit state. We formulate a paradox that cannot be verified by a two-qubit system with local measurements while it is possible by using entanglement measurements. With our scheme…

Quantum Physics · Physics 2019-08-21 Adel Sohbi , Jaewan Kim

It is shown that when properly analyzed using principles consistent with the use of a Hilbert space to describe microscopic properties, quantum mechanics is a local theory: one system cannot influence another system with which it does not…

Quantum Physics · Physics 2020-03-04 Robert B. Griffiths