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Related papers: Closing objectivity loophole in Bell tests on a pu…

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In a Bell test, the set of observed probability distributions complying with the principle of local realism is fully characterized by Bell inequalities. Quantum theory allows for a violation of these inequalities, which is famously regarded…

Quantum Physics · Physics 2022-06-01 Mariami Gachechiladze , Bartłomiej Bąk , Marcin Pawłowski , Nikolai Miklin

Another Bell test "loophole" - imperfect rotational invariance - is explored, and novel realist ideas on parametric down-conversion as used in recent "quantum entanglement" experiments are presented. The usual quantum theory of entangled…

Quantum Physics · Physics 2007-05-23 Caroline H Thompson

It is currently widely accepted, as a result of Bell's theorem and related experiments, that quantum mechanics is inconsistent with local realism and there is the so called quantum non-locality. We show that such a claim can be justified…

Quantum Physics · Physics 2007-05-23 Andrei Khrennikov , Igor Volovich

Self testing is a device independent approach to estimate the state and measurement operators, without the need to assume the dimension of our quantum system. In this paper, we show that one can self test black boxes into any pure entangled…

Quantum Physics · Physics 2013-05-21 Tzyh Haur Yang , Miguel Navascues

Using a new approach to quantum mechanics we revisit Hardy's proof for Bell's theorem and point out a loophole in it. We also demonstrate on this example that quantum mechanics is a local realistic theory.

Quantum Physics · Physics 2007-05-23 Gyula Bene

We examine the satisfaction of Bell criteria for single realizations of quantum systems. This is possible via the joint noisy measurement of all observables involved in the Bell test.We readily find that every outcome violates Bell bounds…

Quantum Physics · Physics 2025-01-24 Alfredo Luis

Bell nonlocality is a fundamental phenomenon of quantum physics as well as an essential resource for various tasks in quantum information processing. It is known that for the observation of nonlocality the measurements on a quantum system…

Quantum Physics · Physics 2025-07-16 Martin Plávala , Otfried Gühne , Marco Túlio Quintino

We present a source of entangled photons that violates a Bell inequality free of the "fair-sampling" assumption, by over 7 standard deviations. This violation is the first experiment with photons to close the detection loophole, and we…

The problem of closing the detection loophole in Bell tests is investigated in the presence of a limited number of efficient detectors using emblematic multipartite quantum states. To this end, a family of multipartite Bell inequalities is…

Quantum Physics · Physics 2018-08-17 Kamil Kostrzewa , Wieslaw Laskowski , Tamas Vertesi

A recent experiment testing the necessity of complex numbers in the standard formulation of quantum theory is recreated using IBM quantum computers. To motivate the experiment, we present a basic construction for real-valued quantum theory.…

Quantum Physics · Physics 2024-12-24 Jarrett L. Lancaster , Nicholas M. Palladino

Quantum Darwinism offers an explanation for the emergence of classical objective features -- those we are used to at macroscopic scales -- from quantum properties at the microscopic level. The interaction of a quantum system with its…

The interpretation of the meaning of Quantum Mechanics has faced controversy since its inception. Bell's inequalities are a touchstone in this controversy. Their observed violation demonstrates that at least one of the hypotheses involved…

Quantum Physics · Physics 2026-03-27 Mónica Agüero , Juliana Bordieu , Alejandro Hnilo , Marcelo Kovalsky , Myriam Nonaka

Bell test is one of the most important tools in quantum information science. On the one hand, it enables fundamental test for the physics laws of nature, and on the other hand, it can be also applied in varieties of device independent tasks…

Quantum Physics · Physics 2015-08-18 Xiao Yuan , Qi Zhao , Xiongfeng Ma

Understanding the emergence of objectivity from the quantum realm has been a long standing issue strongly related to the quantum to classical crossover. Quantum Darwinism provides an answer, interpreting objectivity as consensus between…

Fundamental principle of classical physics -- local realism, means that freely chosen observations can be explained by a local (slower than light) real process. It is apparently violated in quantum mechanics as shown by Bell theorem.…

Quantum Physics · Physics 2015-08-07 Adam Bednorz

The objectivity is a basic requirement for the measurements in the classical world, namely, different observers must reach a consensus on their measurement results, so that they believe that the object exists "objectively" since whoever…

Quantum Physics · Physics 2018-06-04 Sheng-Wen Li , C. Y. Cai , X. F. Liu , C. P. Sun

A recent experiment yielding results in agreement with quantum theory and violating Bell inequalities was interpreted [Nature 526 (29 Octobert 2015) p. 682 and p. 649] as ruling out any local realistic theory of nature. But quantum theory…

Quantum Physics · Physics 2015-12-07 Robert B. Griffiths

A classical model is presented for the features of parametric down-conversion and homodyne detection relevant to recent proposed ``loophole-free'' Bell tests. The Bell tests themselves are uncontroversial: there are no obvious loopholes…

Quantum Physics · Physics 2007-05-23 Caroline H Thompson

The power of quantum computers relies on the capability of their components to maintain faithfully and process accurately quantum information. Since this property eludes classical certification methods, fundamentally new protocols are…

Quantum Physics · Physics 2018-11-07 Pavel Sekatski , Jean-Daniel Bancal , Sebastian Wagner , Nicolas Sangouard

We discuss the connection between the incompatibility of quantum measurements, as captured by the notion of joint measurability, and the violation of Bell inequalities. Specifically, we present explicitly a given a set of non jointly…

Quantum Physics · Physics 2018-02-02 Flavien Hirsch , Marco Túlio Quintino , Nicolas Brunner