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Related papers: Quantum violation of an instrumental test

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This text is an introduction to an operational outlook on Bell inequalities, which has been very fruitful in the past few years. It has lead to the recognition that Bell tests have their own place in applied quantum technologies, because…

Quantum Physics · Physics 2015-06-19 Valerio Scarani

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

Over the past few decades, experimental tests of Bell-type inequalities have been at the forefront of understanding quantum mechanics and its implications. These strong bounds on specific measurements on a physical system originate from…

Bell inequalities follow from a set of seemingly natural assumptions about how to provide a causal model of a Bell experiment. In the face of their violation, two types of causal models that modify some of these assumptions have been…

Quantum Physics · Physics 2022-05-11 Patrick J. Daley , Kevin J. Resch , Robert W. Spekkens

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 probe the foundations of causal structure inference experimentally. The causal structure concerns which events influence other events. We probe whether causal structure can be determined without intervention in quantum systems.…

Quantum Physics · Physics 2024-11-12 Hongfeng Liu , Xiangjing Liu , Qian Chen , Yixian Qiu , Vlatko Vedral , Xinfang Nie , Oscar Dahlsten , Dawei Lu

This short article concentrates on the conceptual aspects of the violation of Bell inequalities, and acts as a map to the 265 cited references. The article outlines (a) relevant characteristics of quantum mechanics, such as statistical…

Quantum Physics · Physics 2021-06-29 Brian Drummond

This study demonstrates the existence of a testable condition for the identification of the causal effect of a treatment on an outcome in observational data, which relies on two sets of variables: observed covariates to be controlled for…

Econometrics · Economics 2026-05-20 Martin Huber , Jannis Kueck

It has been experimentally confirmed that quantum physical phenomena can violate the Information Bell Inequalities. A violation of the one or the other of these Information Bell Inequalites is equivalent to a violation of local realism…

Quantum Physics · Physics 2011-01-11 Gary Bruno Schmid , Rudolf M. Duenki

Generalizations of Bell's theorem, particularly within quantum networks, are now being analyzed through the causal inference lens. However, the exploration of interventions, a central concept in causality theory, remains significantly…

Quantum Physics · Physics 2024-04-09 Davide Poderini , Ranieri Nery , George Moreno , Santiago Zamora , Pedro Lauand , Rafael Chaves

Bell's theorem prompts us with a fundamental inquiry: what is the simplest scenario leading to the incompatibility between quantum correlations and the classical theory of causality? Here we demonstrate that quantum non-classicality is…

Quantum Physics · Physics 2025-12-23 Pedro Lauand , Davide Poderini , Rafael Rabelo , Rafael Chaves

Quantum measurements are crucial for quantum technologies and give rise to some of the most classically counter-intuitive quantum phenomena. As such, the ability to certify the presence of genuinely non-classical joint measurements in a…

Quantum Physics · Physics 2019-05-13 Ciarán M. Lee

Contextuality and entanglement are valuable resources for quantum computing and quantum information. Bell inequalities are used to certify entanglement; thus, it is important to understand why and how they are violated. Quantum mechanics…

Quantum Physics · Physics 2021-08-30 Marian Kupczynski

An active area of research in the fields of machine learning and statistics is the development of causal discovery algorithms, the purpose of which is to infer the causal relations that hold among a set of variables from the correlations…

Quantum Physics · Physics 2015-03-10 Christopher J. Wood , Robert W. Spekkens

Though the topic of causal inference is typically considered in the context of classical statistical models, recent years have seen great interest in extending causal inference techniques to quantum and generalized theories. Causal…

Logic in Computer Science · Computer Science 2023-11-16 Isaac Friend , Aleks Kissinger

It is currently unknown whether the laws of physics permit time travel into the past. While general relativity indicates the theoretical possibility of causality violation, it is now widely accepted that a theory of quantum gravity must…

Quantum Physics · Physics 2014-01-03 Jacques Pienaar

Understanding the physical world fundamentally relies on the assumption that events are temporally ordered, with past events serving as causes for future ones. However, quantum mechanics permits events to occur in a superposition of causal…

Quantum Physics · Physics 2025-08-07 Dengke Qu , Quan Lin , Lei Xiao , Xiang Zhan , Peng Xue

The universality of quantum theory has been questioned ever since it was proposed. Key to this long-unsolved question is to test whether a given physical system has non-classical features. Here we connect recently proposed witnesses of…

Instrumental variables have been widely used to estimate the causal effect of a treatment on an outcome. Existing confidence intervals for causal effects based on instrumental variables assume that all of the putative instrumental variables…

Methodology · Statistics 2020-06-03 Hyunseung Kang , Youjin Lee , T. Tony Cai , Dylan S. Small

Demonstrations of quantum entanglement which confirm the violation of Bell's inequality indicate that under certain conditions action at a distance is possible. This consequence seems to contradict the relativistic principle of causality,…

Quantum Physics · Physics 2018-11-02 Yoram Kirsh