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Related papers: Quantum Counterfactuals and Locality

200 papers

Bell's theorem states that quantum mechanical description on physical quantity cannot be fully explained by local realistic theories, and lays solid basis for various quantum information applications. Hardy's paradox is celebrated to be the…

Quantum Physics · Physics 2024-08-09 Si-Ran Zhao , Shuai Zhao , Hai-Hao Dong , Wen-Zhao Liu , Jing-Ling Chen , Kai Chen , Qiang Zhang , Jian-Wei Pan

We show that quantum oracles provide an advantage over classical oracles for answering classical counterfactual questions in causal models, or equivalently, for identifying unknown causal parameters such as distributions over functional…

Quantum Physics · Physics 2025-12-16 Ciarán M. Gilligan-Lee , Yìlè Yīng , Jonathan Richens , David Schmid

Locally real states of electromagnetic radiation derived from the underlying quantum mechanical formalism are shown to provide an alternative basis for definite polarized states of the widely accepted probabilistic interpretation. The…

General Physics · Physics 2023-07-07 Stuart Mirell , Daniel Mirell

Quantum nonlocality without entanglement (Q-NWE) encapsulates nonlocal behavior of multipartite product states as they may entail global operation for optimal decoding of the classical information encoded within. Here we show that the…

Quantum Physics · Physics 2020-03-25 Some Sankar Bhattacharya , Sutapa Saha , Tamal Guha , Manik Banik

Here it is shown that the simplest description of Bell's experiment according to the canon of von Neumann's theory of measurement explicitly assumes the (Quantum Mechanics-language equivalent of the classical) condition of Locality. This…

Quantum Physics · Physics 2020-02-28 Alejandro Hnilo

We introduce quantum history states and their mathematical framework, thereby reinterpreting and extending the consistent histories approach to quantum theory. Through thought experiments, we demonstrate that our formalism allows us to…

Quantum Physics · Physics 2017-11-08 Jordan Cotler , Frank Wilczek

We argue that it is the assumption of counterfactual definiteness and not locality or realism that results in Bell inequality violations. Furthermore, this assumption of counterfactual definiteness is not supported in classical mechanics.…

Quantum Physics · Physics 2023-12-19 Khaled Mnaymneh

We mathematically axiomatise the stochastics of counterfactuals, by introducing two related frameworks, called counterfactual probability spaces and counterfactual causal spaces, which we collectively term counterfactual spaces. They are,…

Statistics Theory · Mathematics 2026-01-05 Junhyung Park , Fanny Yang , Thomas Icard

We critically discuss the apparent lack of logical rigor pervading the debate on quantum nonlocality. Strong convictions often prevail over rational assessment, leading to the acceptance of loose ideas that become entrenched dogmas. The…

Quantum Physics · Physics 2026-02-11 Justo Pastor Lambare

A model for experiments testing Bell Inequalities is presented that does not involve nonlocal effects. It constitutes essentially a physical explanation of a "loophole" in the logic of these experiments, which, if not excluded, in principle…

General Physics · Physics 2015-03-17 A. F. Kracklauer

Non-locality without entanglement is a rather counter-intuitive phenomenon in which information may be encoded entirely in product (unentangled) states of composite quantum systems in such a way that local measurement of the subsystems is…

Quantum Physics · Physics 2017-03-08 Sarah Croke , Stephen M Barnett

We argue that the claim given in quant-ph/9801014 remains untenable in the revised version. The fallacy in the proof is a misinterpretation of the no-cloning and teleportation theorems, which do not involve time and reference frames.

Quantum Physics · Physics 2007-05-23 Vladimir S. Mashkevich

The principle of non-violation of "information causality", has been proposed as one of the foundational properties of nature\cite{nature}. The main goal of the paper is to explore the gap between quantum mechanical correlations and those…

Quantum Physics · Physics 2017-08-01 Golnaz Zoka , Ali Ahanj

Nonlocality exhibited by ensembles of composite quantum states, wherein local operations and classical communication (LOCC) yield suboptimal discrimination probabilities compared to global strategies, is one of the striking nonclassical…

Quantum Physics · Physics 2025-12-02 Samrat Sen

The question raised by Shimony and Stein is examined and used to explain in more detail a key point of my proof that any theory that conforms to certain general ideas of orthodox relativistic quantum field theory must permit transfers of…

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

Two approaches to extend Hardy's proof of nonlocality without inequalities to maximally entangled states of bipartite two-level systems are shown to fail. On one hand, it is shown that Wu and co-workers' proof [Phys. Rev. A 53, R1927…

Quantum Physics · Physics 2009-10-31 Adan Cabello

A bipartite state is said to be steerable if and only if it does not have a single system description, i.e., the bipartite state cannot be explained by a local hidden state model. Several steering inequalities have been derived using…

Quantum Physics · Physics 2017-02-01 Debasis Mondal , Tanumoy Pramanik , Arun Kumar Pati

The widespread claim that violations of Bell inequalities establish the nonlocality of nature is critically reexamined. It is argued that this conclusion is not logically compelled by either the Einstein-Podolsky-Rosen (EPR) argument or…

Quantum Physics · Physics 2026-05-05 Partha Ghose

We analyze interrelation of quantum and classical entanglement. The latter notion is widely used in classical optic simulation of some quantum-like features of light. We criticize the common interpretation that "quantum nonlocality" is the…

Quantum Physics · Physics 2021-03-26 Andrei Khrennikov

'Locality' is a fraught word, even within the restricted context of Bell's theorem. As one of us has argued elsewhere, that is partly because Bell himself used the word with different meanings at different stages in his career. The…

Quantum Physics · Physics 2018-09-06 Mojtaba Ghadimi , Michael J. W. Hall , Howard M. Wiseman