English
Related papers

Related papers: Locality, Correlations, Information, and non-Hermi…

200 papers

Non-locality without inequality is an elegant argument introduced by L. Hardy for two qubit systems, and later generalised to $n$ qubits, to establish contradiction of quantum theory with local realism. Interestingly, for $n=2$ this…

Quantum Physics · Physics 2015-05-19 Sibasish Ghosh , Shasanka Mohan Roy

We are interested in the problem of characterizing the correlations that arise when performing local measurements on separate quantum systems. In a previous work [Phys. Rev. Lett. 98, 010401 (2007)], we introduced an infinite hierarchy of…

Quantum Physics · Physics 2009-01-16 Miguel Navascues , Stefano Pironio , Antonio Acin

The combination of non-Hermitian physics and strong correlations can give rise to new effects in open quantum many-body systems with balanced gain and loss. We propose a generalized Anderson impurity model that includes non-Hermitian…

Strongly Correlated Electrons · Physics 2018-08-23 Jose A. S. Lourenco , Ronivon L. Eneias , Rodrigo G. Pereira

We analyze nonclassical correlations between outcomes of measurements conducted on two spatial radiation modes. These correlations cannot be simulated with statistical mixtures of coherent states or, more generally, with non-negative…

Quantum Physics · Physics 2022-07-01 V. S. Kovtoniuk , I. S. Yeremenko , S. Ryl , W. Vogel , A. A. Semenov

We use techniques for lower bounds on communication to derive necessary conditions in terms of detector efficiency or amount of super-luminal communication for being able to reproduce with classical local hidden-variable theories the…

Quantum Physics · Physics 2016-12-30 H. Buhrman , P. Hoyer , S. Massar , H. Roehrig

We identify and investigate two classes of non-Hermitian systems, i.e., one resulting from Lorentz-symmetry violation (LSV) and the other from a complex mass (CM) with Lorentz invariance, from the perspective of quantum field theory. The…

Mesoscale and Nanoscale Physics · Physics 2019-08-21 Zi-Yong Ge , Yu-Ran Zhang , Tao Liu , Si-Wen Li , Heng Fan , Franco Nori

A local hidden variable model exploiting the detection loophole to reproduce exactly the quantum correlation of the singlet state is presented. The model is shown to be compatible with both the CHSH and the CH Bell inequalities. Moreover,…

Quantum Physics · Physics 2009-10-31 N. Gisin , B. Gisin

A non-hermitian deformation of the one-dimensional transverse Ising model is shown to have the property of quasi-hermiticity. The transverse Ising chain is obtained from the starting non-hermitian Hamiltonian through a similarity…

Statistical Mechanics · Physics 2009-11-09 Tetsuo Deguchi , Pijush K. Ghosh

Describing systems with non-Hermitian (NH) operators remains a challenge in quantum theory due to instabilities (e.g., exceptional points and decoherence) arising from interactions with the environment. We propose a framework to express the…

Quantum Physics · Physics 2025-03-31 Priyanshi Bhasin , Tanmoy Das

We demonstrate that the local nonfreeness, an unbiased measure of correlation between electrons at a single lattice site, can be computed as the mutual information between local natural spin orbitals. This leads us to prove a general…

Strongly Correlated Electrons · Physics 2026-04-29 Gabriele Bellomia , Adriano Amaricci , Massimo Capone

Quantum Mechanics (QM) predicts the correlation between measurements performed in remote regions of a spatially spread entangled state to be higher than allowed by the intuitive concepts of Locality and Realism (LR). This high correlation…

Quantum Physics · Physics 2019-04-17 Alejandro Hnilo , Mónica Agüero

We show how the Bell correlations can be modelled locally by relaxing the joint probability relation for independent variables $P(a,b)=P(a)P(b)$ outside classical settings, with complex/quaternion generators for the measurement outcomes…

Quantum Physics · Physics 2020-03-11 Anna Karlsson

Bell's theorem, stating that quantum predictions are incompatible with a local hidden variable description, is a cornerstone of quantum theory and at the center of many quantum information processing protocols. Over the years, different…

Quantum Physics · Physics 2020-05-27 I. S. Eliëns , S. G. A. Brito , R. Chaves

This topical review article reports rapid progress on the generalization and application of entanglement in non-Hermitian free-fermion quantum systems. We begin by examining the realization of non-Hermitian quantum systems through the…

Quantum Physics · Physics 2026-01-14 Li-Mei Chen , Yao Zhou , Shuai A. Chen , Peng Ye

Extended quantum mechanics using non-Hermitian, pseudo-Hermitian Hamiltonians is briefly reviewed. Supersymmetric regularizations, solvable simulations and large-N expansion techniques are recollected as suitable means for the study of…

Quantum Physics · Physics 2009-11-10 Miloslav Znojil

I consider the longstanding issue of the hermiticity of the Dirac equation in curved spacetime. Instead of imposing hermiticity by adding ad hoc terms, I renormalize the field by a scaling function, which is related to the determinant of…

Quantum Physics · Physics 2026-04-21 Pasquale Marra

Linear n-local networks are compatible with quantum repeaters based entanglement distribution protocols. Different sources of imperfections such as error in entanglement generation, communication over noisy quantum channels and…

Quantum Physics · Physics 2023-03-23 Kaushiki Mukherjee , Indranil Chakrabarty , Ganesh Mylavarapu

We explore the relation between quantum geometry in non-Hermitian systems and physically measurable phenomena. We highlight various situations in which the behavior of a non-Hermitian system is best understood in terms of quantum geometry,…

Quantum Physics · Physics 2026-03-16 Anton Montag , Tomoki Ozawa

We examine a non-Hermitian (NH) tight-binding system comprising of two orbitals per unit cell and their electrical circuit analogues. We distinguish the PT-symmetric and non-PT symmetric cases characterised by non-reciprocal nearest…

Mesoscale and Nanoscale Physics · Physics 2024-03-11 Dipendu Halder , Ronny Thomale , Saurabh Basu

We introduce the concept of quantum locally recoverable codes (qLRCs) with intersecting recovery sets. We derive a singleton-like bound for these codes by leveraging the additional information provided by the intersecting recovery sets.…

Quantum Physics · Physics 2025-01-20 Kaifeng Bu , Weichen Gu , Xiang Li