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Related papers: Quantum states of macrosystems and entropy

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The rate of entropy production by a stochastic process quantifies how far it is from thermodynamic equilibrium. Equivalently, entropy production captures the degree to which detailed balance and time-reversal symmetry are broken. Despite…

Statistical Mechanics · Physics 2020-12-02 Luca Cocconi , Rosalba Garcia-Millan , Zigan Zhen , Bianca Buturca , Gunnar Pruessner

We consider a generic system composed of a fixed number of particles distributed over a finite number of energy levels. We make only general assumptions about system's properties and the entropy. System's constraints other than fixed number…

Probability · Mathematics 2020-03-12 Tomasz M. Łapiński

The science of thermodynamics was put together in the Nineteenth Century to describe large systems in equilibrium. One part of thermodynamics defines entropy for equilibrium systems and demands an ever-increasing entropy for non-equilibrium…

Statistical Mechanics · Physics 2014-03-26 Leo P. Kadanoff

We consider a quantum spin system consisting of a finite subsystem connected to infinite reservoirs at different temperatures. In this setup we define nonequilibrium steady states and prove that the rate of entropy production in such states…

Mathematical Physics · Physics 2009-10-31 David Ruelle

Chater and MacKay [CM] derived an entropy function of state for exchange economies satisfying a list of axioms, and showed that a change of state of a system of such economies is possible if and only if their total entropy does not…

Mathematical Physics · Physics 2025-10-03 Robert S MacKay

The information on a quantum process acquired through measurements plays a crucial role in the determination of its non-equilibrium thermodynamic properties. We report on the experimental inference of the stochastic entropy production rate…

The content of phase information of an arbitrary phase--sensitive measurement is evaluated using the maximum likelihood estimation. The phase distribution is characterized by the relative entropy--a nonlinear functional of input quantum…

Quantum Physics · Physics 2016-08-15 Zdeněk Hradil , Robert Myška , Tomáš Opatrný , Jiří Bajer

Typically, the entropy of an isolated system in equilibrium is calculated by counting the number of accessible microstates, or in more general cases by using the Gibbs formula. In irreversible processes entropy spontaneously increases and…

Statistical Mechanics · Physics 2020-04-16 Taha A Malik , Rafael Lopez-Mobilia

The paper describes an approach to measuring convergence of an algorithm to its result in terms of an entropy-like function of partitions of its inputs of a given length. The goal is to look at the algorithmic data processing from the…

Computational Complexity · Computer Science 2016-05-06 Anatol Slissenko

It is assumed that the quantum state that may describe a macroscopic system at a given instant of time is one of the eigenstates of the reduced density matrix calculated from the wave function of the system plus its environment. This…

Quantum Physics · Physics 2007-05-23 Gyula Bene

We introduce ways to measure information storage in quantum systems, using a recently introduced computation-theoretic model that accounts for measurement effects. The first, the quantum excess entropy, quantifies the shared information…

Quantum Physics · Physics 2010-04-05 James P. Crutchfield , Karoline Wiesner

We adopt the point of view that (Riemannian) classical and (loop-based) quantum descriptions of geometry are macro- and micro-descriptions in the usual statistical mechanical sense. This gives rise to the notion of geometrical entropy,…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Kirill V. Krasnov

Coherent states (CS) quantum entropy can be split into two components. The dynamical entropy is linked with the dynamical properties of a quantum system. The measurement entropy, which tends to zero in the semiclassical limit, describes the…

chao-dyn · Physics 2009-10-28 Jaroslaw Kwapien , Wojciech Slomczynski , Karol Zyczkowski

In this paper, we present a thought experiment that demonstrates that the equivalence of quantum reduced states and statistical mixed states of ensembles is not merely a simple mathematical formulation in quantum mechanics, but rather…

Quantum Physics · Physics 2025-04-18 Zhihong Zuo

Quantum physics, despite its observables being intrinsically of a probabilistic nature, does not have a quantum entropy assigned to them. We propose a quantum entropy that quantify the randomness of a pure quantum state via a conjugate pair…

Quantum Physics · Physics 2022-10-05 Davi Geiger , Zvi M. Kedem

We develop a martingale theory to describe fluctuations of entropy production for open quantum systems in nonequilbrium steady states. Using the formalism of quantum jump trajectories, we identify a decomposition of entropy production into…

Quantum Physics · Physics 2019-06-12 Gonzalo Manzano , Rosario Fazio , Édgar Roldán

An essential quantity in quantum information theory is the von Neumann entropy which depends entirely on the quantum density operator. Once known, the density operator reveals the statistics of observables in a quantum process, and the…

Systems and Control · Electrical Eng. & Systems 2023-09-08 Mark Balas , Vinod P. Gehlot , Tristan D. Griffith

In this work we study the evolution of Boltzmann's entropy in the context of free expansion of a one dimensional interacting gas inside a box. Boltzmann's entropy is defined for single microstates and is given by the phase-space volume…

Statistical Mechanics · Physics 2023-03-29 Subhadip Chakraborti , Abhishek Dhar , Anupam Kundu

In these notes we will give an overview and road map for a definition and characterization of (relative) entropy for both classical and quantum systems. In other words, we will provide a consistent treatment of entropy which can be applied…

Mathematical Physics · Physics 2025-05-02 W. A. Majewski , L. E. Labuschagne

The quantum ergotropy quantifies the maximal amount of work that can be extracted from a quantum state without changing its entropy. Given that the ergotropy can be expressed as the difference of quantum and classical relative entropies of…

Quantum Physics · Physics 2021-08-26 Akira Sone , Sebastian Deffner