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Related papers: Violation of a Leggett-Garg inequality using ideal…

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We consider a macroscopic quantum system in a tilted double-well potential. By solving Hamiltonian equation, we obtain tunneling probabilities which contain oscillation effects. To show how one can decide between quantum mechanics and the…

Quantum Physics · Physics 2018-08-02 Nasim Shahmansoori , Afshin Shafiee

We consider maximal violations of the Leggett-Garg inequality, obtained by maximising over all possible measurement operators, in relation to non-unitary aspects of the system dynamics. We model the action of an environment on a qubit in…

Quantum Physics · Physics 2013-04-22 Clive Emary

Quantum mechanics violates Leggett-Garg inequalities because the operator formalism predicts correlations between different spin components that would correspond to negative joint probabilities for the outcomes of joint measurements.…

Quantum Physics · Physics 2015-03-20 Yutaro Suzuki , Masataka Iinuma , Holger F. Hofmann

Macrorealism is a classical world view asserting that the properties of macro-objects exist independently and irrespective of observation. One practical approach to test this view in quantum theory is to observe the quantum coherence for…

Quantum Physics · Physics 2020-12-29 A. K. Pan

The rise of quantum information theory has lent new relevance to experimental tests for non-classicality, particularly in controversial cases such as adiabatic quantum computing superconducting circuits. The Leggett-Garg inequality is a…

Quantum Physics · Physics 2015-03-13 Mark M. Wilde , Ari Mizel

Weak measurement has provided new insight into the nature of quantum measurement, by demonstrating the ability to extract average state information without fully projecting the system. For single qubit measurements, this partial projection…

We demonstrate violation of objective realism in quantum world using unconstrained weak measurements. Instead of limited Leggett-Garg approach with artificial bounds on the observed values, we assume two identical and indepenent weak…

In an endeavour to better define the distinction between classical macroscopic and quantum microscopic regimes, the Leggett-Garg inequalities were established as a test of macroscopic-realistic theories, which are commonly thought to be a…

Quantum Physics · Physics 2021-04-14 Hadrien Chevalier , A. J. Paige , Hyukjoon Kwon , M. S. Kim

A recent paper by Souza, Oliveira and Sarthour (SOS) reports the experimental violation of a Leggett-Garg inequality (sometimes referred to as a temporal Bell inequality). The inequality tests for quantum mechanical superposition: if the…

Quantum Physics · Physics 2012-07-13 George C. Knee , Erik M. Gauger , G. Andrew D. Briggs , Simon C. Benjamin

Violations of the Leggett-Garg inequality (LGI) up to its algebraic bound under non-Hermitian dynamics are well established theoretically. Here, we demonstrate that such extreme violations are intrinsically fragile when realistic…

Quantum Physics · Physics 2026-05-14 Sourav Paul , Parveen Kumar , Sourin Das

In this study, we determine a violation of the Leggett-Garg inequalities due to gravitational interaction in a hybrid system consisting of a harmonic oscillator and a spatially localized superposed particle. The violation of the…

Quantum Physics · Physics 2022-08-23 Akira Matsumura , Yasusada Nambu , Kazuhiro Yamamoto

Violation of the Leggett-Garg inequality (LGI) implies quantum phenomena. In this light we establish that the Moreva \textit{et al.} \cite{moreva} experiment demonstrating the Page-Wootter's mechanism \cite{wootters} falls in the quantum…

Quantum Physics · Physics 2017-02-01 D. Gangopadhyay , A. Sinha Roy

We report on a stringent test of the non-classicality of the motion of a massive quantum particle, which propagates on a discrete lattice. Measuring temporal correlations of the position of single atoms performing a quantum walk, we observe…

Quantum Physics · Physics 2015-02-11 Carsten Robens , Wolfgang Alt , Dieter Meschede , Clive Emary , Andrea Alberti

We construct quantifiable generalisations of Leggett-Garg tests for macro/ mesoscopic realism and noninvasive measurability that apply when not all outcomes of measurement can be identified as arising from one of two macroscopically…

Quantum Physics · Physics 2024-12-13 L. Rosales-Zárate , B. Opanchuk , Q. Y. He , M. D. Reid

The Leggett-Garg inequality (LGI) is a powerful tool for distinguishing between quantum and classical properties in studies of macroscopic systems. Applying the LGI to non-Hermitian systems with dissipation presents a fascinating…

Quantum Gases · Physics 2024-11-06 Qinxuan Peng , Bolong Jiao , Hang Yu , Liao Sun , Haoyi Zhang , Jiaming Li , Le Luo

We investigate both analytically and numerically violations of a Leggett-Garg inequality (LGI) for a composite quantum system in contact with two separate reservoirs at different temperatures. Remarkably we find that LGI violations can be…

Mesoscale and Nanoscale Physics · Physics 2015-06-15 Juan C. Castillo , Ferney J. Rodríguez , Luis Quiroga

We revisit the study of the violation of the Leggett-Garg inequality in neutrino oscillation data as a mean to test some of the fundamental aspects of quantum mechanics. In particular, we consider the results of the Daya Bay and RENO…

High Energy Physics - Phenomenology · Physics 2025-03-26 Ricardo Zamora Barrios , Mario A. Acero

We investigate the nonclassicality of an open quantum system using Leggett-Garg inequality (LGI) which test the correlations of a single system measured at different times. Violation of LGI implies nonclassical behavior of the open system.…

Quantum Physics · Physics 2017-04-11 Md. Manirul Ali , Po-Wen Chen

This study investigates the emergence of macroscopic classical behavior from quantum foundations via the entropic Leggett--Garg inequality. We introduce a geometric framework for deriving entropic Leggett--Garg inequalities with…

Quantum Physics · Physics 2025-12-01 Qi-Hong Cai , Xue-Hao Yu , Ma-Cheng Yang , Ao-Xiang Liu , Cong-Feng Qiao

In the tests for macrorealism proposed by Leggett and Garg, the temporal correlation functions of a dichotomic variable Q must be measured in a non-invasive way to rule out alternative classical explanations of Leggett-Garg inequality…

Quantum Physics · Physics 2019-02-27 J. J. Halliwell