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Related papers: Quantum operator entropies under unitary evolution

200 papers

The von Neumann entropy plays a vital role in quantum information theory. The von Neumann entropy determines, e.g., the capacities of quantum channels. Also, entropies of composite quantum systems are important for future quantum networks,…

Quantum Physics · Physics 2018-10-31 Christian Majenz

The Lindblad equation is widely employed in studies of Markovian quantum open systems. Here, firstly, a simple result is presented on the time evolution of the non Neumann entropy under the Lindblad equation, which enables one to examine if…

Quantum Physics · Physics 2016-10-18 Congjie Ou , Ralph V. Chamberlin , Sumiyoshi Abe

An attempt toward the operational formulation of quantum thermodynamics is made by employing the recently proposed operations forming positive operator-valued measures for generating thermodynamic processes. The quantity of heat as well as…

Statistical Mechanics · Physics 2015-06-04 Sumiyoshi Abe , Yuki Aoyaghi

We derive a well-behaved nonlinear extension of the non-relativistic Liouville-von Neumann dynamics driven by maximal entropy production with conservation of energy and probability. The pure state limit reduces to the usual Schroedinger…

Quantum Physics · Physics 2009-11-06 S. Gheorghiu-Svirschevski

This study discusses the quantum behavior of a particle, which is controlled by fluctuations in the physical space-time (ST) variables, rather than provides a novel interpretation of quantum theory. The fluctuations, i.e., inhomogeneities…

General Physics · Physics 2012-06-15 Valery Egorushkin

We consider the analysis of probability distributions through their associated covariance operators from reproducing kernel Hilbert spaces. We show that the von Neumann entropy and relative entropy of these operators are intimately related…

Information Theory · Computer Science 2022-08-29 Francis Bach

We propose a series of quantum algorithms for computing a wide range of quantum entropies and distances, including the von Neumann entropy, quantum R\'{e}nyi entropy, trace distance, and fidelity. The proposed algorithms significantly…

Quantum Physics · Physics 2024-07-29 Qisheng Wang , Ji Guan , Junyi Liu , Zhicheng Zhang , Mingsheng Ying

For any choice of initial state and weak assumptions about the Hamiltonian, large isolated quantum systems undergoing Schrodinger evolution spend most of their time in macroscopic superposition states. The result follows from von Neumann's…

Quantum Physics · Physics 2021-08-18 Roman V. Buniy , Stephen D. H. Hsu

We define the entropy operator as the negative of the logarithm of the density matrix, give a prescription for extracting its thermodynamically measurable part, and discuss its dynamics. For an isolated system we derive the first, second…

Statistical Mechanics · Physics 2016-07-06 E. Solano-Carrillo , A. J. Millis

In this note we lay some groundwork for the resource theory of thermodynamics in general probabilistic theories (GPTs). We consider theories satisfying a purely convex abstraction of the spectral decomposition of density matrices: that…

Quantum Physics · Physics 2015-11-06 Howard Barnum , Jonathan Barrett , Marius Krumm , Markus P. Müller

We review with a tutorial scope the information theory foundations of quantum statistical physics. Only a small proportion of the variables that characterize a system at the microscopic scale can be controlled, for both practical and…

Statistical Mechanics · Physics 2007-05-23 R. Balian

In this work, we use the theory of quantum states over time to define an entropy $S(\rho,\mathcal{E})$ associated with quantum processes $(\rho,\mathcal{E})$, where $\rho$ is a state and $\mathcal{E}$ is a quantum channel responsible for…

Quantum Physics · Physics 2023-07-24 James Fullwood , Arthur J. Parzygnat

It is shown that the existence of a time operator in the Liouville space representation of both classical and quantum evolution provides a mechanism for effective entropy change of physical states. In particular, an initially effectively…

Quantum Physics · Physics 2016-09-08 Eli Eisenberg , Larry Horwitz

The change of the von Neumann entropy of a set of harmonic oscillators initially in thermal equilibrium and interacting linearly with an externally driven quantum system is computed by adapting the Feynman-Vernon influence functional…

Statistical Mechanics · Physics 2018-04-04 Erik Aurell , Ralf Eichhorn

Students in quantum mechanics class are taught that the wave function contains all knowable information about an isolated system. Later in the course, this view seems to be contradicted by the mysterious density matrix, which introduces a…

General Physics · Physics 2021-04-16 Mark G. Kuzyk

Thermodynamic entropy, as defined by Clausius, characterizes macroscopic observations of a system based on phenomenological quantities such as temperature and heat. In contrast, information-theoretic entropy, introduced by Shannon, is a…

Quantum Physics · Physics 2017-01-04 Mirjam Weilenmann , Lea Krämer , Philippe Faist , Renato Renner

We find a new effect for the behaviour of Von Neumann entropy. For this we derive the framework for describing Von Neumann entropy in non-Hermitian quantum systems and then apply it to a simple interacting PT symmetric bosonic system. We…

Quantum Physics · Physics 2019-08-01 Andreas Fring , Thomas Frith

Despite its enormous empirical success, the formalism of quantum theory still raises fundamental questions: why is nature described in terms of complex Hilbert spaces, and what modifications of it could we reasonably expect to find in some…

Quantum Physics · Physics 2017-04-27 Marius Krumm , Howard Barnum , Jonathan Barrett , Markus P. Mueller

The entropy accumulation theorem states that the smooth min-entropy of an $n$-partite system $A = (A_1, \ldots, A_n)$ is lower-bounded by the sum of the von Neumann entropies of suitably chosen conditional states up to corrections that are…

Quantum Physics · Physics 2019-07-23 Frédéric Dupuis , Omar Fawzi

In quantum mechanics, outcomes of measurements on a state have a probabilistic interpretation while the evolution of the state is treated deterministically. Here we show that one can also treat the evolution as being probabilistic in nature…

Quantum Physics · Physics 2009-11-10 J. Oppenheim , B. Reznik