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Related papers: Quantum Crossovers Revealed by Local Measurements

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Multiparty quantum states are useful for a variety of quantum information and computation protocols. We define a multiparty entanglement measure based on local measurements on a multiparty quantum state, and an entanglement measure averaged…

An analysis is given of the local phase space of gravity coupled to matter to second order in perturbation theory. Working in local regions with boundaries at finite distance, we identify matter, Coulomb, and additional boundary modes. The…

General Relativity and Quantum Cosmology · Physics 2024-02-09 Viktoria Kabel , Časlav Brukner , Wolfgang Wieland

A fundamental challenge in digital quantum simulation (DQS) is the control of inherent errors. These appear when discretizing the time evolution generated by the Hamiltonian of a quantum many-body system as a sequence of quantum gates,…

Quantum Physics · Physics 2020-05-05 Markus Heyl , Philipp Hauke , Peter Zoller

Although cosmic expansion at very small distances is usually dismissed as entirely inconsequential, these extraordinarily small effects may in fact have a real and significant influence on our world. A calculation suggests that the minute…

General Physics · Physics 2007-05-23 C. L. Herzenberg

Non-equilibrium dynamics of many-body quantum systems under the effect of measurement protocols is attracting an increasing amount of attention. It has been recently revealed that measurements may induce different non-equilibrium regimes…

Statistical Mechanics · Physics 2023-09-13 Emanuele Tirrito , Alessandro Santini , Rosario Fazio , Mario Collura

Phase transitions are driven by collective fluctuations of a system's constituents that emerge at a critical point. This mechanism has been extensively explored for classical and quantum systems in equilibrium, whose critical behavior is…

Quantum dynamics in a strongly disordered quantum many-body system show localization properties. The initial state memory is maintained owing to slow relaxation when the system is in the localized regime. This work demonstrates how…

Quantum Physics · Physics 2024-01-12 Kazue Kudo

Fundamental principle of classical physics -- local realism, means that freely chosen observations can be explained by a local (slower than light) real process. It is apparently violated in quantum mechanics as shown by Bell theorem.…

Quantum Physics · Physics 2015-08-07 Adam Bednorz

Topological quantum phases cannot be characterized by local order parameters in the bulk. In this work however, we show that signatures of a topological quantum critical point do remain in local observables in the bulk, and manifest…

Statistical Mechanics · Physics 2017-01-25 Sthitadhi Roy , Roderich Moessner , Arnab Das

Quantum criticality provides a means to understand the apparent non-Fermi liquid phenomena in correlated electron systems. How to properly describe quantum critical points in electronic systems has however been poorly understood. The issues…

Strongly Correlated Electrons · Physics 2009-11-07 Qimiao Si

Quantum tomography is one of the major challenges of large-scale quantum information research due to the exponential time complexity. In this work, we develop and apply a Bayesian state estimation method to experimentally demonstrate…

Quantum Physics · Physics 2025-11-13 Yang Zhengning , Shihao Ru , Lianzhen Cao , Nikolay Zheludev , Weibo Gao

Quantum metrology fundamentally relies upon the efficient management of quantum uncertainties. We show that, under equilibrium conditions, the management of quantum noise becomes extremely flexible around the quantum critical point of a…

Quantum Physics · Physics 2018-07-18 Irénée Frérot , Tommaso Roscilde

Proposed experiments for obtaining empirical evidence for a quantum description of gravity in a table-top setting focus on detecting quantum information signatures, such as entanglement or non-Gaussianity production, in gravitationally…

Quantum Physics · Physics 2025-12-19 Thomas Strasser , Marios Christodoulou , Richard Howl , Caslav Brukner

We consider monitored quantum systems with a global conserved charge, and ask how efficiently an observer ("eavesdropper") can learn the global charge of such systems from local projective measurements. We find phase transitions as a…

Recently, we proposed a method for the local detection of quantum correlations on the basis of local measurements and state tomography at different instances in time [Phys. Rev. Lett. 107, 180402 (2011)]. The method allows for the detection…

Quantum Physics · Physics 2013-04-30 Manuel Gessner , Heinz-Peter Breuer

The detection of entanglement provides a definitive proof of quantumness. Its ascertainment might be challenging for hot or macroscopic objects, where entanglement is typically weak, but nevertheless present. Here we propose a platform for…

Quantum Physics · Physics 2023-05-10 Tanjung Krisnanda , Tomasz Paterek , Mauro Paternostro , Timothy C. H. Liew

Quantum nonlocality is often judged by violations of Bell-type inequalities for a given state. The computation of such violations is a global task, requiring evaluation of global correlations and subsequent testing against a Bell…

Quantum Physics · Physics 2025-11-04 Rohit Kishan Ray

We study the effects of symmetry-breaking defects at continuous quantum transitions (CQTs), which may arise from localized external fields coupled to the order-parameter operator. The problem is addressed within renormalization-group (RG)…

Statistical Mechanics · Physics 2022-05-10 Alessio Franchi , Davide Rossini , Ettore Vicari

The descriptions of the quantum realm and the macroscopic classical world differ significantly not only in their mathematical formulations but also in their foundational concepts and philosophical consequences. When and how physical systems…

Quantum Physics · Physics 2008-12-02 Johannes Kofler

We review methods that allow one to detect and characterise quantum correlations in many-body systems, with a special focus on approaches which are scalable. Namely, those applicable to systems with many degrees of freedom, without…

Quantum Physics · Physics 2023-09-28 Irénée Frérot , Matteo Fadel , Maciej Lewenstein