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Related papers: No-hidden-variables proof for two spin-1/2 particl…

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A recent proposal for a superdeterministic account of quantum mechanics, named Invariant-set theory, appears to bring ideas from several diverse fields like chaos theory, number theory and dynamical systems to quantum foundations. However,…

Quantum Physics · Physics 2022-03-11 Indrajit Sen

It is shown that any separable state on Hilbert space ${\cal H}={\cal H}_1\otimes{\cal H}_2$, can be written as a convex combination of N pure product states with $N\leq (dim{\cal H})^2$. Then a new separability criterion for mixed states…

Quantum Physics · Physics 2009-10-30 Pawel Horodecki

Parallels between the notions of nonlinear pseudobosons and of an apparent non-Hermiticity of observables as shown in paper I (arXiv: 1109.0605) are demonstrated to survive the transition to the quantum models based on the use of unbounded…

Mathematical Physics · Physics 2012-03-06 Fabio Bagarello , Miloslav Znojil

State representations summarize our knowledge about a system. When unobservable quantities are introduced the state representation is typically no longer unique. However, this non-uniqueness does not affect subsequent inferences based on…

Quantum Physics · Physics 2009-11-10 Kae Nemoto , Samuel L. Braunstein

We develop criteria to detect three classes of nonlocality that have been shown by Wiseman et al. [Phys. Rev. Lett. 98, 140402 (2007)] to be nonequivalent: entanglement, EPR steering, and the failure of local hidden-variable theories. We…

Quantum Physics · Physics 2015-03-19 Q. Y. He , P. D. Drummond , M. D. Reid

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

We discuss two new demonstrations of the Bell-Kochen-Specker theorem: a state-independent proof using 14 four-dimensional propositions, based on a suggestion made by Clifton, and a state-specific proof involving 5 propositions on the…

Quantum Physics · Physics 2009-10-30 Adan Cabello , Jose M. Estebaranz , Guillermo Garcia Alcaine

Wave-particle duality has become one of the flagships of quantum mechanics. This counter-intuitive concept is highlighted in a delayed choice experiment, where the experimental setup that reveals either the particle or wave nature of a…

Quantum Physics · Physics 2018-05-16 Rafael Chaves , Gabriela Barreto Lemos , Jacques Pienaar

In this paper we investigate the quantum dynamics of two spin-1 systems, $\vec{\textbf{S}}_1$ and $\vec{\textbf{S}}_2$, adopting a generalized $(\vec{\textbf{S}}_1+\vec{\textbf{S}}_2)^2$-nonconserving Heisenberg model. We show that, due to…

Quantum Physics · Physics 2017-10-17 R. Grimaudo , A. Messina , P. A. Ivanov , N. V. Vitanov

We show that higher order inter-group covariances involving even number of qubits are necessarily positive semidefinite for N qubit separable states, which are completely symmetric under permutations of the qubits. This identification leads…

Quantum Physics · Physics 2009-11-13 A. R. Usha Devi , R. Prabhu , A. K. Rajagopal

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

Absolutely separable states form a special subset of the set of all separable states, as they remain separable under any global unitary transformation unlike other separable states. In this work we consider the set of absolutely separable…

Quantum Physics · Physics 2015-06-18 Nirman Ganguly , Jyotishman Chatterjee , A. S. Majumdar

Quantifying mixed-state entanglement in many-body systems has been a formidable task. In this work, we quantify the entanglement of states in unresolvable spin ensembles, which are inherently mixed. By exploiting their permutationally…

Quantum Physics · Physics 2025-11-05 Tzu-Wei Kuo , Hoi-Kwan Lau

Entanglement between three or more parties exhibits a realm of properties unknown to two-party states. Bipartite states are easily classified using the Schmidt decomposition. The Schmidt coefficients of a bipartite pure state encompass all…

Quantum Physics · Physics 2008-12-18 Julia Kempe

We consider the discrimination of two-party quantum states and provide a quantum data-hiding scheme using two-qubit separable states. We first provide a bound on the optimal local discrimination of two-party quantum states, and establish a…

Quantum Physics · Physics 2025-12-18 Donghoon Ha , Jeong San Kim

The duality principle, a cornerstone of quantum mechanics, limits the coexistence of wave and particle behaviours of quantum systems. This limitation takes a quantitative form when applied to the visibility $\mathcal V$ and predictability…

Quantum Physics · Physics 2014-06-20 Jonathan Leach , Eliot Bolduc , Filippo. M. Miatto , Kevin Piche , Gerd Leuchs , Robert W. Boyd

We present a new set of inseparabilty inequalities to detect entanglement in $N$-spin states. These are based on negative partial transposition and involve collective spin-spin correlations of any two partitions of the entire system. They…

Quantum Physics · Physics 2016-08-08 Asoka Biswas

Coherent states offer a promising path for near-term quantum computing due to their inherent protection against bit-flip noise. However, their large photon numbers can be challenging for numerical simulation. This paper introduces an…

Quantum entanglement reflects itself through non-local correlations among the subsystems of a quantum system. This thesis focuses on constructing a complete set of local invariants characterizing symmetric two qubit systems and analyzing…

Quantum Physics · Physics 2009-07-14 M. S. Uma

Whenever a mathematical proposition to be proved requires more information than it is contained in an axiomatic system, it can neither be proved nor disproved, i.e. it is undecidable, or logically undetermined, within this axiomatic system.…

Quantum Physics · Physics 2009-12-06 Caslav Brukner