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Quantum machine learning (QML) is rapidly transitioning from theoretical promise to practical relevance across data-intensive scientific domains. In this Review, we provide a structured overview of recent advances that bridge foundational…

Quantum Physics · Physics 2026-02-25 Vinit Singh , Amandeep Singh Bhatia , Mandeep Kaur Saggi , Manas Sajjan , Sabre Kais

Correlations between different partitions of quantum systems play a central role in a variety of many-body quantum systems, and they have been studied exhaustively in experimental and theoretical research. Here, we investigate dynamical…

In the framework of quantum computational tensor network [D. Gross and J. Eisert, Phys. Rev. Lett. {\bf98}, 220503 (2007)], which is a general framework of measurement-based quantum computation, the resource many-body state is represented…

Quantum Physics · Physics 2012-08-02 Tomoyuki Morimae , Keisuke Fujii

We develop a novel approach to phase transitions in quantum spin models based on a relation to their classical counterparts. Explicitly, we show that whenever chessboard estimates can be used to prove a phase transition in the classical…

Mathematical Physics · Physics 2011-11-10 Marek Biskup , Lincoln Chayes , Shannon Starr

The spin-boson (SB) model is a standard prototype for quantum dissipation, which we generalize in this work, to explore the dissipative effects on a one-dimensional spin-orbit (SO) coupled particle in the presence of a sub-ohmic bath. We…

Statistical Mechanics · Physics 2026-02-02 Sudip Sinha , Subhasis Sinha , Sushanta Dattagupta

Quantile regression is a powerful tool capable of offering a richer view of the data as compared to least-squares regression. Quantile regression is typically performed individually on a few quantiles or a grid of quantiles without…

Methodology · Statistics 2026-03-26 Ta-Hsin Li , Nimrod Megiddo

This report introduces a novel class of reasoning architectures, termed Quantum Circuit Reasoning Models (QCRM), which extend the concept of Variational Quantum Circuits (VQC) from energy minimization and classification tasks to structured…

Quantum Physics · Physics 2025-12-10 Andrew Kiruluta

The strong-coupling perturbation theory (SCPT) for correlated electron systems is extended to the case of full Coulomb interaction. The Coulomb mechanism of the orbital polarization is discussed and attention is paid to the importance of…

Strongly Correlated Electrons · Physics 2007-05-23 I. Sandalov , U. Lundin , O. Eriksson

We consider measurement-based quantum computation using the state of a spin-lattice system in equilibrium with a thermal bath and free to evolve under its own Hamiltonian. Any single qubit measurements disturb the system from equilibrium…

Quantum Physics · Physics 2009-09-23 David Jennings , Andrzej Dragan , Sean D. Barrett , Stephen D. Bartlett , Terry Rudolph

Quantum mechanics describes the unitary time evolution of closed systems. In practice, every quantum system interacts with the environment leading to an irreversible loss of coherence. The Spin-Boson model (SBM) is central to the…

Chemical Physics · Physics 2020-09-28 Nirmalendu Acharyya , Martin Richter , Benjamin P. Fingerhut

Qubit reset is crucial in quantum technology and is typically achieved by coupling the qubit to a dissipative environment. However, the achievable speed and fidelity are limited by qubit-environment entanglement. We use exact tensor-network…

Quantum Physics · Physics 2026-03-11 Carlos Ortega-Taberner , Eoin O'Neill , Paul Eastham

Fluctuation theorems establish exact relations for nonequilibrium dynamics, profoundly advancing the field of stochastic thermodynamics. In this work, we extend quantum fluctuation theorems beyond the traditional thermodynamic framework to…

Quantum Physics · Physics 2026-02-24 Kun Zhang , Mo-Yang Ni , Hai-Long Shi , Xiao-Hui Wang , Jin Wang

We study an arbitrary non-equilibrium dynamics of a quantum bipartite system coupled to a reservoir. For its characterization, we present a fluctuation theorem (FT) that explicitly addresses the quantum correlation of subsystems during the…

Quantum Physics · Physics 2020-05-22 Jung Jun Park , Hyunchul Nha , Sang Wook Kim , Vlatko Vedral

We introduce a new method for representing the low energy subspace of a bosonic field theory on the qubit space of digital quantum computers. This discretization leads to an exponentially precise description of the subspace of the…

Quantum Physics · Physics 2018-10-17 Alexandru Macridin , Panagiotis Spentzouris , James Amundson , Roni Harnik

The equipartition theorem is a fundamental law of classical statistical physics, which states that every degree of freedom contributes $k_{B}T/2$ to the energy, where $T$ is the temperature and $k_{B}$ is the Boltzmann constant. Recent…

Statistical Mechanics · Physics 2024-09-17 Xin-Hai Tong

We investigate a quantum metrological protocol operating in a non-Markovian environment by employing the quantum Brownian motion (QBM) model, in which the system is linearly coupled to a reservoir of harmonic oscillators. Specifically, we…

Leveraging the extraordinary phenomena of quantum superposition and quantum correlation, quantum computing offers unprecedented potential for addressing challenges beyond the reach of classical computers. This paper tackles two pivotal…

Quantum Physics · Physics 2023-12-14 Ming-Hao Wang , Hua Lu

Quantum Rabi model (QRM) is a fundamental model for light-matter interactions, the finite-component quantum phase transition (QPT) in the QRM has established a paradigmatic application for critical quantum metrology (CQM). However, such a…

Quantum Physics · Physics 2026-05-12 Qiu-Yi Chen , Feng Qiao , Zu-Jian Ying

The Gell-Mann & Low theorem is a cornerstone of Quantum Field Theory (QFT) and condensed matter physics, and many-body perturbation theory is a foundational tool for treating interactions. However, their integration into quantum algorithms…

Quantum Physics · Physics 2023-12-01 Chun-Tse Li , T. Tzen Ong , Lucas Wang , Ming-Chien Hsu , Hsin Lin , Min-Hsiu Hsieh

We derive an extension to the quantum regression theorem which facilitates the calculation of two-time correlation functions and emission spectra for systems undergoing non-Markovian evolution. The derivation exploits projection operator…

Quantum Physics · Physics 2016-05-04 Dara P. S. McCutcheon