English
Related papers

Related papers: Beyond the Quantum Regression Theorem in Variation…

200 papers

Correlation functions of quantum systems -- central objects in quantum field theories -- are defined in high-dimensional space-time domains. Their numerical treatment thus suffers from the curse of dimensionality, which hinders the…

Strongly Correlated Electrons · Physics 2023-05-01 Hiroshi Shinaoka , Markus Wallerberger , Yuta Murakami , Kosuke Nogaki , Rihito Sakurai , Philipp Werner , Anna Kauch

Quantum measurement is a physical process. What physical resources and constraints does quantum mechanics require for measurement to produce the classical world we observe? Treating measurement as a fully unitary quantum process, our goal…

Quantum Physics · Physics 2025-12-09 Vishal Johnson , Ashmeet Singh , Reimar Leike , Philipp Frank , Torsten Enßlin

Channel conversion constitutes a pivotal paradigm in information theory and its applications to quantum physics, providing a unified problem setting that encompasses celebrated results such as Shannon's noisy-channel coding theorem. Quantum…

Quantum Physics · Physics 2025-09-10 Masahito Hayashi , Hayata Yamasaki

Quantum algorithms for quantum dynamics simulations are traditionally based on implementing a Trotter-approximation of the time-evolution operator. This approach typically relies on deep circuits and is therefore hampered by the substantial…

Quantum Physics · Physics 2022-01-06 Alexander Miessen , Pauline J. Ollitrault , Ivano Tavernelli

The field of quantum resource theory (QRT) has emerged as an invaluable framework for the examination of small and strongly correlated quantum systems, surpassing the boundaries imposed by traditional statistical treatments. The fundamental…

Quantum Physics · Physics 2023-08-29 Gökhan Torun , Onur Pusuluk , Özgür E. Müstecaplıoğlu

The experimental access to ultra-strong couplings in light-matter interactions has made the quantum phase transition (QPT) in the quantum Rabi model practically relevant, while the physics of the QPT has not yet been fully explored. The…

Quantum Physics · Physics 2025-12-29 Feng Qiao , Qiu-Yi Chen , Zu-Jian Ying

Describing open quantum systems far from equilibrium is challenging, in particular when the environment is mesoscopic, when it develops nonequilibrium features during the evolution, or when the memory effects cannot be disregarded. Here, we…

Quantum Physics · Physics 2021-03-17 Andreu Riera-Campeny , Anna Sanpera , Philipp Strasberg

A causal, non-Hermitian, renormalizable, local, unitary and Lorentz convariant formulation of Quantum Theory (QT) (= Quantum Mechanics (QM) and Quantum Field Theory (QFT)) is developed which is free of formalistic problems we face in the…

High Energy Physics - Phenomenology · Physics 2011-07-19 F. Kleefeld

In this paper we present a new approach for testing QM against the realism aspect of hidden variable theory (HVT). We consider successive measurements of non-commuting operators on a input spin $s$ state. The key point is that, although…

Quantum Physics · Physics 2007-05-23 Ali Ahanj , Pramod Joag

Quantum reservoir computers (QRCs) have emerged as a promising approach to quantum machine learning, since they utilize the natural dynamics of quantum systems for data processing and are simple to train. Here, we consider $n$-qubit quantum…

Quantum Physics · Physics 2026-04-09 Markus Gross , Hans-Martin Rieser

Quantum machine learning applies principles such as superposition and entanglement to data processing and optimization. Variational quantum models operate on qubits in high-dimensional Hilbert spaces and provide an alternative approach to…

Machine Learning · Computer Science 2026-03-02 Miras Seilkhan , Adilbek Taizhanov

Quantile regression (QR) is a principal regression method for analyzing the impact of covariates on outcomes. The impact is described by the conditional quantile function and its functionals. In this paper we develop the nonparametric…

Quantile Regression (QR) provides a way to approximate a single conditional quantile. To have a more informative description of the conditional distribution, QR can be merged with deep learning techniques to simultaneously estimate multiple…

Machine Learning · Computer Science 2022-02-01 Axel Brando , Joan Gimeno , Jose A. Rodríguez-Serrano , Jordi Vitrià

We propose a general extended coherent state approach to the qubit (or fermion) and multi-mode boson coupling systems. The application to the spin-boson model with the discretization of a bosonic bath with arbitrary continuous spectral…

Quantum Gases · Physics 2015-05-14 Yu-Yu Zhang , Qing-Hu Chen , Ke-Lin Wang

The simulation of quantum transport in a realistic, many-particle system is a nontrivial problem with no quantitatively satisfactory solution. While real-time propagation has the potential to overcome the shortcomings of conventional…

Mesoscale and Nanoscale Physics · Physics 2015-10-16 Justin E. Elenewski , Yanxiang Zhao , Hanning Chen

Flood prediction is a critical challenge in the context of climate change, with significant implications for ecosystem preservation, human safety, and infrastructure protection. In this study, we tackle this problem by applying the…

Quantum Physics · Physics 2024-07-12 Chu-Hsuan Abraham Lin , Chen-Yu Liu , Kuan-Cheng Chen

In this paper we investigate the robustness of the quantum correlations against the environment effects in various opto-mechanical bipartite systems. For two spatially separated opto-mechanical cavities, we give analytical formula for the…

Quantum Physics · Physics 2015-12-09 J. El Qars , M. Daoud , Ahl Laamara

The time-convolutionless quantum master equation is an exact description of the nonequilibrium dynamics of open quantum systems, with the advantage of being local in time. We derive a perturbative expansion to arbitrary order in the…

Mesoscale and Nanoscale Physics · Physics 2019-03-14 Konstantin Nestmann , Carsten Timm

This work addresses quantum adiabatic decoherence of many-body spin systems coupled with a boson field in the framework of open quantum systems theory. We generalize the traditional spin-boson model by considering a system-environment…

Quantum Physics · Physics 2021-11-04 H. H. Segnorile , C. E. González , R. C. Zamar

This paper describes perturbative framework, on the basis of closed-time-path formalism, for studying quasiuniform relativistic quantum field systems near equilibrium and nonequilibrium quasistationary systems. At the first part, starting…

High Energy Physics - Theory · Physics 2007-05-23 A. Niégawa