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Related papers: The Physics of crypto-nonlocality

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Violating a nonlocality inequality enables the most powerful remote quantum information tasks and fundamental tests of quantum physics. Loophole-free photonic verification of nonlocality has been achieved with polarization-entangled photon…

Einstein, Podolsky and Rosen (EPR) pointed out that the quantum-mechanical description of "physical reality" implied an unphysical, instantaneous action between distant measurements. To avoid such an action at a distance, EPR concluded that…

Quantum Physics · Physics 2009-11-07 Daniele Tommasini

The empirical validity of the locality (LOC) principle of relativity is used to argue in favour of a local hidden variable theory (HVT) for individual quantum processes. It is shown that such a HVT may reproduce the statistical predictions…

Quantum Physics · Physics 2007-05-23 W. De Baere

Quantum theory puts forward phenomena unexplainable by classical physics - or information, for that matter. A prominent example is non-locality. Non-local correlations cannot be explained, in classical terms, by shared information but only…

Quantum Physics · Physics 2014-08-26 Helen Ebbe , Stefan Wolf

The insight due to John Bell that the joint behavior of individually measured entangled quantum systems cannot be explained by shared information remains a mystery to this day. We describe an experiment, and its analysis, displaying…

Quantum Physics · Physics 2014-12-05 C. Bernhard , B. Bessire , A. Montina , M. Pfaffhauser , A. Stefanov , S. Wolf

We report on the first experimental realization of the entanglement witness for polarization entangled photons. It represents a recently discovered significant quantum information protocol which is based on few local measurements. The…

Quantum Physics · Physics 2013-05-29 M. Barbieri , F. De Martini , G. Di Nepi , P. Mataloni , G. M. D'Ariano , C. Macchiavello

Nonlocality and quantum entanglement constitute two special aspects of the quantum correlations existing in quantum systems, which are of paramount importance in quantum-information theory. Traditionally, they have been regarded as…

Quantum Physics · Physics 2015-05-27 J. Batle , M. Casas

Instantaneous measurements of non-local observables between space-like separated regions can be performed without violating causality. This feat relies on the use of entanglement. Here we propose novel protocols for this task and the…

Quantum Physics · Physics 2015-05-20 Salman Beigi , Robert Koenig

Quantum information science has leaped forward with the exploration of high-dimensional quantum systems, offering greater potential than traditional qubits in quantum communication and quantum computing. To advance the field of…

Characterization and categorization of quantum correlations are both fundamentally and practically important in quantum information science. Although quantum correlations such as non-separability, steerability, and non-locality can be…

We present a loophole-free violation of local realism using entangled photon pairs. We ensure that all relevant events in our Bell test are spacelike separated by placing the parties far enough apart and by using fast random number…

Local unitary transforms cannot affect the quantum correlations between two systems sharing an entangled state although they do influence the outcomes of local measurements. By considering local squeezing operations we introduce an extended…

Quantum Physics · Physics 2023-11-15 A. Lezama , A. Auyuanet

Leggett formulated an inequality which seems to generalize the Bell theorem to non-local hidden variable theories. Leggett inequality is violated by quantum mechanics, as was confirmed by experiment. However, a careful analysis reveals that…

Quantum Physics · Physics 2011-04-12 A. Di Lorenzo

We show that controlled interference of a particle's wavefunction can be used to perform a quantum mechanical measurement in an incomplete basis. This happens because the measurement projects the particle into a lower dimensional subspace…

Quantum Physics · Physics 2007-05-23 R. Srikanth

We present a simple hidden variable model for the singlet state of a pair of qubits, characterized by two kinds, hierarchically ordered, of hidden variables. We prove that, averaging over both types of variables, one reproduces all the…

Quantum Physics · Physics 2015-06-04 GianCarlo Ghirardi , Raffaele Romano

I have been arguing that quantum nonlocality, deeply entrenched in the present formalism of quantum mechanics and widely believed as a reality by physicists, is in fact absent. Spooky nonlocal state reduction is the most, and perhaps the…

Quantum Physics · Physics 2007-05-23 C . S. Unnikrishnan

The celebrated Einstein-Podolsky-Rosen quantum steering has a complex structure in the multipartite scenario. We show that a naively defined criterion for multipartite steering allows, like in Bell nonlocality, for a contradictory effect…

Quantum Physics · Physics 2021-05-07 M. M. Taddei , T. L. Silva , R. V. Nery , G. H. Aguilar , S. P. Walborn , L. Aolita

Quantum non-locality is normally defined via violations of Bell's inequalities that exclude certain classical hidden variable theories from explaining quantum correlations. Another definition of non-locality refers to the wave-function…

Quantum Physics · Physics 2018-08-01 Armen E. Allahverdyan , Arshag Danageozian

In this paper we study the correlations that arise when two separated parties perform measurements on systems they hold locally. We restrict ourselves to those correlations with which arbitrarily fast transmission of information is…

Quantum Physics · Physics 2009-11-11 Nick S. Jones , Lluis Masanes

We investigated coherence delocalization on a coupled-cavity molecular polariton platform in time, frequency, and spatial domains, enabled by ultrafast two-dimensional infrared hyperspectral imaging. Unidirectional coherence delocalization…

Quantum Physics · Physics 2021-07-12 Bo Xiang , Zimo Yang , Yi-Zhuang You , Wei Xiong