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Related papers: Unsharp eigenvalues and quantum contextuality

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Adopting the frame of mesoscopic physics, we describe a Bell type experiment involving time-delayed two-particle correlation measurements. The indistinguishability of quantum particles results in a specific interference between different…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 A. V. Lebedev , G. Blatter

Non-commutative spacetime and quantum groups have been argued to capture non-classical features of spacetime and its symmetries in the low-energy limit of quantum gravity. In this letter, we show that employing the $SU_q(2)$ quantum group…

Quantum Physics · Physics 2026-05-29 Vittorio D'Esposito , Giuseppe Fabiano , Domenico Frattulillo

In this paper we attempt to discuss what has Kochen-Specker (KS) theorem to say about physical invariance and quantum individuality. In particular, we will discuss the impossibility of making reference to objective physical properties…

Quantum Physics · Physics 2017-10-10 Christian de Ronde , Cesar Massri

Quantum contextuality is one of the fundamental notions in quantum mechanics. Proofs of the Kochen-Specker theorem and noncontextuality inequalities are two means for revealing the contextuality phenomenon in quantum mechanics. It has been…

Quantum Physics · Physics 2015-09-08 Xiao-Dong Yu , Yan-Qing Guo , D. M. Tong

For spin-1/2 particles, using a suitable Mach-Zehnder-type setup with a spin-flipper, we argue that it is a direct consequence of the quantum mechanical treatment that an experimentally verifiable \textit{subensemble} mean of the measured…

Quantum Physics · Physics 2015-05-14 Alok Kumar Pan , Dipankar Home

We present a detailed motivation for and definition of the contextual values of an observable, which were introduced by Dressel et al. [Phys. Rev. Lett. 104 240401 (2010)]. The theory of contextual values extends the well-established theory…

Quantum Physics · Physics 2012-02-29 J. Dressel , A. N. Jordan

For any state in four-dimensional system, the quantum violation of an inequality based on the Peres-Mermin proof for testing noncontextual realist models has experimentally been corroborated. In the Peres-Mermin proof, an array of nine…

Quantum Physics · Physics 2015-05-19 Alok Kumar Pan

The violation of a Bell inequality is an experimental observation that forces one to abandon a local realistic worldview, namely, one in which physical properties are (probabilistically) defined prior to and independent of measurement and…

For eight-dimensional quantum systems there is a Kochen-Specker (KS) set of 40 quantum yes-no tests that is related to the Greenberger-Horne-Zeilinger (GHZ) proof of Bell's theorem. Here we experimentally implement this KS set using an…

The Heisenberg microscope provides a powerful mental image of the measurement process of quantum mechanics (QM), attempting to explain the uncertainty relation through an uncontrollable back-action from the measurement device. However,…

Quantum Physics · Physics 2026-04-23 Jan-Åke Larsson

Unarticulated, implicit hypotheses in Bell's analysis of Einstein, Podolsky and Rosen (EPR) correlations are identified and examined. These relate to the mathematical-analytical properties of random variables, the character of the relevant…

Quantum Physics · Physics 2007-05-23 A. F. Kracklauer , N. A. Kracklauer

A necessary condition for the probabilities of a set of events to exhibit Bell nonlocality or Kochen-Specker contextuality is that the graph of exclusivity of the events contains induced odd cycles with five or more vertices, called odd…

Quantum Physics · Physics 2024-02-16 Lucas E. A. Porto , Rafael Rabelo , Marcelo Terra Cunha , Adán Cabello

The assumption of local realism in a Bell locality scenario imposes non-trivial conditions on the Shannon entropies of the associated probability distributions, expressed by linear entropic Bell inequalities. In principle, these entropic…

Quantum Physics · Physics 2013-06-24 Rafael Chaves

EPR showed that two particles emitted from a source can be entangled by a shared wavefunction where two non-commuting observables (position, momentum) can be simultaneously real, leading to a contradiction with quantum mechanics (two…

Quantum Physics · Physics 2026-03-12 Mafiz Uddin

Correlations for the Bell gedankenexperiment are constructed using probabilities given by quantum mechanics, and nonlocal information. They satisfy Bell's inequality and exhibit spatial non stationarity in angle. Correlations for three…

Quantum Physics · Physics 2015-06-26 Louis Sica

Bell's theorem shows that no hidden-variable model can explain the measurement statistics of a quantum system shared between two parties, thus ruling out a classical (local) understanding of nature. In this work we demonstrate that by…

Quantum Physics · Physics 2022-03-14 Benjamin Morris , Lukas J. Fiderer , Ben Lang , Daniel Goldwater

Is is shown here that the "simple test of quantumness for a single system" of arXiv:0704.1962 (for a recent experimental realization see arXiv:0804.1646) has exactly the same relation to the discussion of to the problem of describing the…

Quantum Physics · Physics 2009-11-13 Marek Zukowski

It has been argued that any test of quantum contextuality is nullified by the fact that perfect orthogonality and perfect compatibility cannot be achieved in finite precision experiments. We introduce experimentally testable two-qutrit…

Quantum Physics · Physics 2011-05-17 Adan Cabello , Marcelo Terra Cunha

A proof of Bell's theorem without inequalities and involving only two observers is given by suitably extending a proof of the Bell-Kochen-Specker theorem due to Mermin. This proof is generalized to obtain an inequality-free proof of Bell's…

Quantum Physics · Physics 2007-05-23 P. K. Aravind

Recent experiments allowed concluding that Bell-type inequalities are indeed violated thus it is important to understand what it means and how can we explain the existence of strong correlations between outcomes of distant measurements. Do…

Quantum Physics · Physics 2017-12-05 Marian Kupczynski