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Related papers: Algebraic maximum violation of the Leggett-Garg in…

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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

The Leggett-Garg (LG) test of macroscopic realism involves a series of dichotomic non-invasive measurements that are used to calculate a function which has a fixed upper bound for a macrorealistic system and a larger upper bound for a…

Quantum Physics · Physics 2017-02-23 Hemant Katiyar , Aharon Brodutch , Dawei Lu , Raymond Laflamme

The Leggett-Garg inequality (LGI) is a temporal analogue of Bell's inequality and provides a quantitative test of the nonclassicality of a system through its violation. We analytically investigate the violation of the LGI in the context of…

General Relativity and Quantum Cosmology · Physics 2026-01-29 Kimihiro Nomura , Akira Taniguchi , Kazushige Ueda

The Leggett-Garg inequalities impose restrictions on the values taken by some combinations of the two-time correlation functions of observables in order to be explainable by a noninvasive-realist classical model. While in the unitary…

Quantum Physics · Physics 2021-01-19 Javid Naikoo , Subhashish Banerjee , R. Srikanth

We investigate Leggett-Garg temporal inequalities in flavor-mixing processes. We derive an exact flavor-mass uncertainty product and we establish that it is an upper bound to the violation of the inequalities. This finding relates temporal…

Quantum Physics · Physics 2021-12-10 Massimo Blasone , Fabrizio Illuminati , Luciano Petruzziello , Luca Smaldone

We show how to apply the Leggett-Garg inequality to opto-electro-mechanical systems near their quantum ground state. We find that by using a dichotomic quantum non-demolition measurement (via, e.g., an additional circuit-QED measurement…

Quantum Physics · Physics 2012-09-17 Neill Lambert , Robert Johansson , Franco Nori

Wigner's form of the local realist inequality is used to derive its temporal version for an oscillating two-level system involving two-time joint probabilities. Such an inequality may be regarded as a novel form of the Leggett-Garg…

Quantum Physics · Physics 2015-03-24 Debashis Saha , Shiladitya Mal , Prasanta K. Panigrahi , Dipankar Home

Quantum theory contravenes classical macrorealism by allowing a system to be in a superposition of two or more physically distinct states, producing physical consequences radically different from that of classical physics. We show that a…

Quantum Physics · Physics 2026-02-03 Arijit Chatterjee , H. S. Karthik , T. S. Mahesh , A. R. Usha Devi

We investigate the violation of the Leggett-Garg inequalities for a quantum field, focusing on the two-time quasi-probability distribution function of the dichotomic variable with a coarse-grained scalar field. The Leggett-Garg inequalities…

Quantum Physics · Physics 2023-11-07 Masaki Tani , Kosei Hatakeyama , Daisuke Miki , Yuki Yamasaki , Kazuhiro Yamamoto

For multilevel spin systems, robustness of the quantum mechanical (QM) violation of macrorealism (MR) with respect to coarse grained measurements is investigated using three different necessary conditions of MR, namely, the Leggett-Garg…

Quantum Physics · Physics 2016-12-28 Shiladitya Mal , Debarshi Das , Dipankar Home

In contrast to the spatial Bell's inequalities, which probe entanglement between spatially-separated systems, the Leggett-Garg inequalities test the correlations of a single system measured at different times. Violation of a genuine…

Quantum Physics · Physics 2014-01-31 Clive Emary , Neill Lambert , Franco Nori

Nonclassicality of temporal correlations pertaining to noncommutative sequential measurements is defined through the violation of macrorealistic inequalities, known as Leggett-Garg inequalities (LGI). We investigate the energy cost of the…

Quantum Physics · Physics 2018-09-11 Titas Chanda , Tamoghna Das , Shiladitya Mal , Aditi Sen De , Ujjwal Sen

Despite the great success of quantum mechanics, questions regarding its application still exist and the boundary between quantum and classical mechanics remains unclear. Based on the philosophical assumptions of macrorealism and noninvasive…

Quantum Physics · Physics 2012-04-24 Jin-Shi Xu , Chuan-Feng Li , Xu-Bo Zou , Guang-Can Guo

We interpret the Leggett-Garg (LG) inequality as a kind of contextual probabilistic inequality in which one combines data collected in experiments performed for three different contexts. In the original version of the inequality these…

Neurons and Cognition · Quantitative Biology 2015-06-18 Masanari Asano , Takahisa Hashimoto , Andrei Khrennikov , Masanori Ohya , Yoshiharu Tanaka

We study various formulations of Leggett-Garg inequality (LGI), specifically, the Wigner and Clauser-Horne forms of LGI, in the context of subatomic systems, in particular, three flavor neutrino as well as meson systems. The optimal forms…

High Energy Physics - Phenomenology · Physics 2020-08-04 Javid Naikoo , Swati Kumari , Subhashish Banerjee , A. K. Pan

In a recent paper, Chatterjee et al. [Phys. Rev. Lett 135, 220202 (2025)] analyze and experimentally implement a specific unitary evolution of a simple quantum system. The authors refer to this type of dynamics as a "superposition of…

Quantum Physics · Physics 2026-01-27 Antoni Wójcik , Jan Wójcik

Macrorealism (MR) is the world view that certain quantities may take definite values at all times irrespective of past or future measurements and may be experimentally falsified via the Leggett-Garg (LG) inequalities. We put this world view…

Quantum Physics · Physics 2023-12-06 Clement Mawby , Jonathan Halliwell

We show violations of Leggett-Garg inequalities to be possible for single-mode cat-states evolving dynamically in the presence of a nonlinear quantum interaction arising from, for instance, a Kerr medium. In order to prove the results, we…

Quantum Physics · Physics 2019-04-03 Manushan Thenabadu , Margaret Reid

In this work we study temporal quantum correlations, quantified by Leggett-Garg (LG) and LG-type inequalities, in the $B$ and $K$ meson systems. We use the tools of open quantum systems to incorporate the effect of decoherence which is…

High Energy Physics - Phenomenology · Physics 2018-04-04 Javid Naikoo , Ashutosh Kumar Alok , Subhashish Banerjee

We investigate how discrete internal degrees of freedom in a quasi-macroscopic system affect the violation of the Leggett--Garg inequality, a test of macroscopic-realism based on temporal correlation functions. As a specific example, we…