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Related papers: Leggett's theorem without inequalities

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Does quantum theory apply at all scales, including that of observers? New light on this fundamental question has recently been shed through a resurgence of interest in the long-standing Wigner's friend paradox. This is a thought experiment…

In the Leggett-Garg approach to testing macrorealism, the two-time correlation functions, which are normally obtained by sequential measurements of a dichotomic variable Q, need to be measured in a non-invasive way in order to exclude…

Quantum Physics · Physics 2016-11-23 J. J. Halliwell

The Leggett-Garg (LG) inequalities were proposed in order to assess whether sets of pairs of sequential measurements on a single quantum system can be consistent with an underlying notion of macrorealism. Here, the LG inequalities are…

Quantum Physics · Physics 2016-03-02 J. J. Halliwell

A recent paper by two of us and co-workers, based on an extended Wigner's friend scenario, demonstrated that certain empirical correlations predicted by quantum theory (QT) violate inequalities derived from a set of metaphysical assumptions…

Quantum Physics · Physics 2023-09-20 Howard M. Wiseman , Eric G. Cavalcanti , Eleanor G. Rieffel

The celebrated Bell's no-go theorem rules out the hidden-variable theories falling in the hypothesis of locality and causality, by requiring the theory to model the quantum correlation-at-a-distance phenomena. Here I develop an independent…

Quantum Physics · Physics 2024-09-19 Doriano Brogioli

We use a simple relational framework to develop the key notions and results on hidden variables and non-locality. The extensive literature on these topics in the foundations of quantum mechanics is couched in terms of probabilistic models,…

Quantum Physics · Physics 2014-06-10 Samson Abramsky

It is shown that the quantum theory can be formulated on homogeneous spaces of generalized coherent states in a manner that accounts for interference, entanglement, and the linearity of dynamics without using the superposition principle.…

Quantum Physics · Physics 2007-05-23 Daniel I. Fivel

In this work we relate the well-known no-go theorem that two non-orthogonal (mixed) quantum states cannot be perfectly discriminated, to the general principle in physics, the no-signalling condition. In fact, we derive the minimum error in…

Quantum Physics · Physics 2010-09-23 Joonwoo Bae , Jae-Weon Lee , Jaewan Kim , Won-Young Hwang

A novel no-go theorem is presented which sets a bound upon the extent to which '\Psi-epistemic' interpretations of quantum theory are able to explain the overlap between non-orthogonal quantum states in terms of an experimenter's ignorance…

Quantum Physics · Physics 2013-05-23 O. J. E. Maroney

We extend to any maximally entangled state of a bipartite system whose constituents are arbitrarily (but finite) dimensional the result, recently derived for two-dimensional constituents, that hidden variable theories cannot have local…

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

An obstacle to realize supersymmetry on a lattice is the breakdown of Leibniz rule. We give a proof of a no-go theorem that it is impossible to construct a lattice field theory in an infinite lattice volume with any nontrivial field…

High Energy Physics - Lattice · Physics 2010-01-21 Mitsuhiro Kato , Makoto Sakamoto , Hiroto So

A proof of Bell's theorem without inequalities for two maximally entangled particles is proposed using the technique of quantum teleportation. It follows Hardy's arguments for a non-maximally entangled state with the help of two auxiliary…

Quantum Physics · Physics 2007-05-23 W. LiMing

Quantum theory is indeterministic, but not completely so. When a system is in a pure state there are properties it possesses with certainty, known as actual properties. The actual properties of a quantum system (in a pure state) fully…

Quantum Physics · Physics 2022-11-30 Victoria J Wright

In 1985, Leggett and Garg put forward the concept of macroscopic realism (macrorealism) and, in analogy to Bell's theorem, derived a necessary condition in terms of inequalities, which are now known as the Leggett-Garg inequalities. In this…

Quantum Physics · Physics 2013-05-15 Johannes Kofler , Caslav Brukner

There exist diverse no-go theorems, ranging from no-cloning to monogamies of quantum correlations and Bell inequality violations, which restrict the processing of information in the quantum world. In a multipartite scenario, monogamy of…

Quantum Physics · Physics 2015-05-26 Debasis Sadhukhan , Sudipto Singha Roy , Debraj Rakshit , Aditi Sen De , Ujjwal Sen

This paper makes 3 contributions. First, it generalizes the Lindeberg\textendash Feller and Lyapunov Central Limit Theorems to Hilbert Spaces by way of $L^2$. Second, it generalizes these results to spaces in which sample failure and…

Statistics Theory · Mathematics 2022-12-12 Julian Morimoto

If the time evolution of a system can be understood classically, then there must exist an underlying probability distribution for the variables describing the system at all times. It is well known that for systems described by a single…

Quantum Physics · Physics 2019-10-09 J. J. Halliwell , C. Mawby

Stringent restrictions for model building are imposed by a no-go theorem in noncommutative gauge field theory. Circumventing this theorem is crucial for the construction of realistic models of particle interactions. To this end, the…

High Energy Physics - Theory · Physics 2008-11-26 Masato Arai , Sami Saxell , Anca Tureanu , Nobuhiro Uekusa

We consider two necessary and sufficient conditions for macrorealism recently appeared in the literature, known as no-signaling-in-time and arrow-of-time conditions, respectively, and study them in the context of neutrino flavor…

High Energy Physics - Theory · Physics 2023-08-07 Massimo Blasone , Fabrizio Illuminati , Luciano Petruzziello , Kyrylo Simonov , Luca Smaldone

A hidden variable model reproducing the quantum mechanical probabilities for a spin singlet is presented. The model violates only the hypothesis of independence of the distribution for the hidden variables from the detectors settings and…

Quantum Physics · Physics 2012-06-11 Antonio Di Lorenzo