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Related papers: Quantum theory cannot violate a causal inequality

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Bell's theorem reveals a profound conflict between quantum mechanics and local realism, a conflict we reinterpret through the modern lens of causal inference. We propose and computationally validate a framework where quantum entanglement…

Quantum Physics · Physics 2025-08-28 Pilsung Kang

A recent framework of quantum theory with no global causal order predicts the existence of "causally nonseparable" processes. Some of these processes produce correlations incompatible with any causal order (they violate so-called "causal…

Quantum Physics · Physics 2016-08-23 Adrien Feix , Mateus Araújo , Časlav Brukner

Quantum theory in a global space-time gives rise to non-local correlations, which cannot be explained causally in a satisfactory way; this motivates the study of theories with reduced global assumptions. Oreshkov, Costa, and Brukner (2012)…

Quantum Physics · Physics 2014-10-10 Ämin Baumeler , Adrien Feix , Stefan Wolf

Contrary to counterfactual definiteness quantum theory teaches us that measuring instruments are not passively reading predetermined values of physical observables. Counterfactual definiteness allows proving Bell inequalities. If the…

Quantum Physics · Physics 2016-11-28 Marian Kupczynski

The phenomenon of quantum entanglement is explained in a way which is fully consistent with Einstein's Special Theory of Relativity. A subtle flaw is identified in the logic supporting the view that Bell's Inequality precludes all local…

Quantum Physics · Physics 2007-05-23 Jeremy L. Fellows

Developing a quantum analog of the modern classical theory of causation, as formulated by Pearl and others using directed acyclic graphs, requires a theory of random or stochastic time development at the microscopic level, where the…

Quantum Physics · Physics 2024-12-10 Robert B. Griffiths

Why do correlations between the results of measurements performed on physical systems violate Bell and non-contextuality inequalities up to some specific limits? The answer may follow from the observation that in quantum theory, unlike in…

The strength of classical correlations is subject to certain constraints, commonly known as Bell inequalities. Violation of these inequalities is the manifestation of nonlocality---displayed, in particular, by quantum mechanics, meaning…

Quantum Physics · Physics 2015-03-18 R. Augusiak , J. Stasińska , C. Hadley , J. K. Korbicz , M. Lewenstein , A. Acín

Bell's theorem supposedly demonstrates an irreconcilable conflict between quantum mechanics and local, realistic hidden variable theories. Most proofs of Bell's theorem, are based on inequalities. In this paper we present an alternative…

Quantum Physics · Physics 2025-03-10 Andrea Aiello

J.S. Bell's work has convinced many that correlations in violation of CHSH inequalities show that the world itself is non-local, and that there is an apparently essential conflict between any sharp formulation of quantum theory and…

Quantum Physics · Physics 2012-08-01 Richard Healey

Quantum theory violates Bell's inequality, but not to the maximum extent that is logically possible. We derive inequalities (generalizations of Cirel'son's inequality) that quantify the upper bound of the violation, both for the standard…

Quantum Physics · Physics 2009-11-07 Dennis Dieks

Simulation tasks are insightful tools to compare information-theoretic resources. Considering a generalization of usual Bell scenarios where external quantum inputs are provided to the parties, we show that any entangled quantum state…

Quantum Physics · Physics 2013-06-06 Denis Rosset , Cyril Branciard , Nicolas Gisin , Yeong-Cherng Liang

Quantum theory is in principle compatible with processes that violate causal inequalities, an analogue of Bell inequalities that constrain the correlations observed by sets of parties operating in a definite causal order. Since the…

Quantum Physics · Physics 2025-04-22 Zixuan Liu , Giulio Chiribella

We will show for undergraduate and graduate students of physics that Quantum Mechanics is an incomplete and non-local theory. The problem of non-locality is discussed by analyzing the Bell's theorem where are considered correlations between…

General Physics · Physics 2011-03-03 M. Cattani

From the modern perspective of causal inference, Bell's theorem -- a fundamental signature of quantum theory -- is a particular case where quantum correlations are incompatible with the classical theory of causality, and the generalization…

Quantum Physics · Physics 2024-05-30 Pedro Lauand , Bereket Ngussie Bekele , Elie Wolfe

The problem of using observed correlations to infer causal relations is relevant to a wide variety of scientific disciplines. Yet given correlations between just two classical variables, it is impossible to determine whether they arose from…

We show one can use classical fields to modify a quantum optics experiment so that Bell's inequalities will be violated. This happens with continuous random variables that are local, but we need to use the correlation matrix to prove there…

Quantum Physics · Physics 2007-05-23 Patrick Suppes , J. Acacio de Barros , Adonai S. Sant'Anna

The correspondence principle suggests that quantum systems grow classical when large. Classical systems cannot violate Bell inequalities. Yet agents given substantial control can violate Bell inequalities proven for large-scale systems. We…

Quantum Physics · Physics 2021-02-10 Adam Bene Watts , Nicole Yunger Halpern , Aram Harrow

From the beginning of quantum mechanics, there has been a discussion about the concept of reality, as exemplified by the EPR paradox. To many, the idea of the paradox and the possibility of local hidden variables was dismissed by the Bell…

Quantum Physics · Physics 2012-03-15 David K. Ferry , Laszlo B. Kish

We will demonstrate in this paper that Bell's theorem (Bell's inequality) does not really conflict with quantum mechanics, the controversy between them originates from the different definitions for the expectation value using the…

Quantum Physics · Physics 2007-05-23 Zheng-Chuan Wang