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Related papers: Algorithm of Reduction

200 papers

Vertex direction algorithms have been around for a few decades in the experimental design and mixture models literature. We briefly review this type of algorithm and describe a new member of the family: the support reduction algorithm. The…

Statistics Theory · Mathematics 2009-09-29 Piet Groeneboom , Geurt Jongbloed , Jon A. Wellner

We derive the strong subadditivity of the von Neumann entropy with a strict lower bound dependent on the distribution of quantum correlation in the system. We investigate the structure of states saturating the bounded subadditivity and…

Quantum Physics · Physics 2022-05-26 L. R. S. Mendes , M. C. de Oliveira

We introduce a well-defined and unbiased measure of the strength of correlations in quantum many-particle systems which is based on the relative von Neumann entropy computed from the density operator of correlated and uncorrelated states.…

Strongly Correlated Electrons · Physics 2015-05-30 K. Byczuk , J. Kunes , W. Hofstetter , D. Vollhardt

By numerically exact calculations of spin-1/2 antiferromagnetic Heisenberg models on small clusters, we demonstrate that quantum entanglement between subsystems $A$ and $B$ in a pure ground state of a whole system $A+B$ can induce thermal…

Quantum Physics · Physics 2020-10-20 Kazuhiro Seki , Seiji Yunoki

For a quantum system undergoing non-Markovian open quantum dynamics, we demonstrate a tomography algorithm based on multi-time measurements of the system, which reconstructs a minimal environment coupled to the system, such that the system…

Quantum Physics · Physics 2022-08-31 Chu Guo

We develop a rigorous treatment of discontinuous stochastic unitary evolution for a system of quantum particles that interacts singularly with quantum "bubbles" at random instants of time. This model of a "cloud chamber" allows to watch and…

Mathematical Physics · Physics 2007-05-23 V. P. Belavkin

A theory of quantum state reduction is advanced. It is based on two principles: (1) Gauge decomposition; (2) Maximum entropy. To wit: (1) The reduction decomposition of a state vector is the Schmidt decomposition with respect to the states…

Quantum Physics · Physics 2009-01-05 Vladimir S. Mashkevich

Optimization problems in disciplines such as machine learning are commonly solved with iterative methods. Gradient descent algorithms find local minima by moving along the direction of steepest descent while Newton's method takes into…

Quantum Physics · Physics 2018-08-20 Patrick Rebentrost , Maria Schuld , Leonard Wossnig , Francesco Petruccione , Seth Lloyd

To simulate plasma phenomena, large-scale computational resources have been employed in developing high-precision and high-resolution plasma simulations. One of the main obstacles in plasma simulations is the requirement of computational…

Quantum Physics · Physics 2025-11-17 Hayato Higuchi , Yuki Ito , Kazuki Sakamoto , Keisuke Fujii , Akimasa Yoshikawa

This paper tackles the data-driven approximation of unknown dynamical systems using Koopman-operator methods. Given a dictionary of functions, these methods approximate the projection of the action of the operator on the finite-dimensional…

Systems and Control · Electrical Eng. & Systems 2023-02-28 Masih Haseli , Jorge Cortés

An approach to the description of subdynamics inside non-relativistic quantum field theory is presented, in which the notions of relevant observable, time scale and complete positivity of the time evolution are stressed. A scattering theory…

Quantum Physics · Physics 2009-11-07 Ludovico Lanz , Bassano Vacchini

The minimal ingredients to describe a quantum system are a Hamiltonian, an initial state, and a preferred tensor product structure that encodes a decomposition into subsystems. We explore a top-down approach in which the subsystems emerge…

Quantum Physics · Physics 2025-08-19 Nicolas Loizeau , Dries Sels

We propose a method to interpolate dynamics of von Neumann and classical master equations with an arbitrary mixing parameter to investigate the thermal effects in quantum dynamics. The two dynamics are mixed by intervening to continuously…

Quantum Physics · Physics 2018-02-13 Tadashi Kadowaki

The challenge of understanding quantum measurement persists as a fundamental issue in modern physics. Particularly, the abrupt and energy-non-conserving collapse of the wave function appears to contradict classical thermodynamic laws. The…

Quantum Physics · Physics 2026-03-10 Sophie Engineer , Tom Rivlin , Sabine Wollmann , Mehul Malik , Maximilian P. E. Lock

In this work we give a comprehensive derivation of an exact and numerically feasible method to perform ab-initio calculations of quantum particles interacting with a quantized electromagnetic field. We present a hierachy of…

Theory and methods to obtain parametric reduced-order models by moment matching are presented. The definition of the parametric moment is introduced, and methods (model-based and data-driven) for the approximation of the parametric moment…

Systems and Control · Electrical Eng. & Systems 2025-06-13 Hanqing Zhang , Junyu Mao , Mohammad Fahim Shakib , Giordano Scarciotti

Based oh the properties of Lie algebras, in this work we develop a general framework to linearize the von-Neumann equation rendering it in a suitable form for quantum simulations. We show that one of these linearizations of the von-Neumann…

Quantum Physics · Physics 2024-02-08 Alejandro Kunold

A microscopic understanding of the thermodynamic entropy in quantum systems has been a mystery ever since the invention of quantum mechanics. In classical physics, this entropy is believed to be the logarithm of the volume of phase space…

Quantum Physics · Physics 2013-05-08 J. M. Deutsch , Haibin Li , Auditya Sharma

In this paper, we discuss that an observable-based single-system Copenhagen and entanglement-based two-system von Neumann measurement protocols in quantum theory can be made equivalent by considering the second part of the two-system scheme…

General Physics · Physics 2015-08-17 Daegene Song

We analyse the reconstruction of an unknown pure qubit state. We derive the optimal guess that can be inferred from any set of measurements on N identical copies of the system with the fidelity as a figure of merit. We study in detail the…

Quantum Physics · Physics 2007-05-23 E. Bagan , M. Baig , A. Monras , R. Munoz-Tapia