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Related papers: Projection operator formalism and entropy

200 papers

Based on the q-exponential distribution which has been observed in more and more physical systems, the varentropy method is used to derive the uncertainty measure of such an abnormal distribution function. The uncertainty measure obtained…

Mathematical Physics · Physics 2010-09-07 Congjie Ou , Aziz El Kaabouchi , Qiuping A. Wang , Jincan Chen

The usual canonical Hamiltonian or Lagrangian formalism of classical mechanics applied to macroscopic systems describes energy conserving adiabatic motion. If irreversible diabatic processes are to be included, then the law of increasing…

Classical Physics · Physics 2009-11-13 J. Silverberg , A. Widom

The standard formulation of thermostatistics, being based on the Boltzmann-Gibbs distribution and logarithmic Shannon entropy, describes idealized uncorrelated systems with extensive energies and short-range interactions. In this letter, we…

Statistical Mechanics · Physics 2020-07-01 S. N. Saadatmand , Tim Gould , E. G. Cavalcanti , J. A. Vaccaro

Based on Landauer's principle, we provide a geometrical definition for the entropy of a given static, spherically symmetric spacetime. Considering a congruence of geodesics across a surface, one defines the entropy of a congruence as the…

General Relativity and Quantum Cosmology · Physics 2026-05-29 J. M. Isidro , B. Koch , A. Rincon

Based on a recent proof of free choices in linking equations to the experiments they describe, I clarify relations among some purely mathematical entities featured in quantum mechanics (probabilities, density operators, partial traces, and…

Quantum Physics · Physics 2014-09-15 John M. Myers

Assuming that a threshold Ornstein-Uhlenbeck process is observed at discrete time instants, we propose generalized moment estimators to estimate the parameters. Our theoretical basis is the celebrated ergodic theorem. To use this theorem we…

Statistics Theory · Mathematics 2020-11-24 Yaozhong Hu , Yuejuan Xi

We derive an Ito stochastic differential equation for entropy production in nonequilibrium Langevin processes. Introducing a random-time transformation, entropy production obeys a one-dimensional drift-diffusion equation, independent of the…

Statistical Mechanics · Physics 2017-10-10 Simone Pigolotti , Izaak Neri , Édgar Roldán , Frank Jülicher

We consider open quantum systems weakly coupled to a heat reservoir and driven by arbitrary time-dependent parameters. We derive exact microscopic expressions for the nonequilibrium entropy production and entropy production rate, valid…

Statistical Mechanics · Physics 2012-10-24 Sebastian Deffner , Eric Lutz

In this paper, I expand Shannon's definition of entropy into a new form of entropy that allows integration of information from different random events. Shannon's notion of entropy is a special case of my more general definition of entropy.…

Machine Learning · Computer Science 2008-11-04 Stefan Jaeger

The expression for the density operator of the damped harmonic oscillator is derived from the master equation in the framework of the Lindblad theory for open quantum systems. Then the von Neumann entropy and effective temperature of the…

Quantum Physics · Physics 2007-05-23 A. Isar

Taking only the characteristics as absolute, in the spirit of Arnold's "Geometrical Methods in the Theory of Ordinary Differential Equations" (Springer, 1988), we give an independent of coordinates formulation of general variational entropy…

Analysis of PDEs · Mathematics 2009-12-07 Gheorghe Minea

Non-equilibrium stochastic dynamics of several active Brownian systems are modeled in terms of non-linear velocity dependent force. In general, this force may consist of both even and odd functions of velocity. We derive the expression for…

Statistical Mechanics · Physics 2016-09-14 Debasish Chaudhuri

A way to construct Boltzmann entropy, i.e., the entropy as a function of a microscopic pure state, for quantum field systems is proposed. Operators that shift the field in wavevector space are used in the construction. By employing an…

Statistical Mechanics · Physics 2020-03-25 Kyo Yoshida

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

We propose the use of the functional determinant of geometric operators in constructing an entropy functional associated to geometric flows. Our approach is based on the direct computation of the partition function, with a well-defined set…

Differential Geometry · Mathematics 2013-11-25 Christopher Lin

In statistical physics, the Nakajima-Mori-Zwanzig projection operator formalism is used to derive an integro-differential equation for observables in a Hilbert space, the generalized Langevin equation (GLE). This technique relies on the…

Mathematical Physics · Physics 2026-04-27 Christoph Widder , Johannes Zimmer , Tanja Schilling

In this work, the definition of the density operator on quantum states in Hilbert spaces and some of its aspects relevant in thermodynamics and information-theoretical entropy calculations are given. In this framework, a physical model…

Mathematical Physics · Physics 2017-09-25 Isiaka Aremua , Mahouton Norbert Hounkonnou , Ezinvi Baloitcha

The paper deals with the generalization of both Boltzmann entropy and distribution in the light of most-probable interpretation of statistical equilibrium. The statistical analysis of the generalized entropy and distribution leads to some…

Quantum Physics · Physics 2009-11-13 C. G. Chakrabarti , Indranil Chakrabarty

A formal linear vector field representation for scientific equations is developed to rationalize the intuitive methods that are constantly employed. It is shown that unlike mechanical units that appear in the basis of the space, the reduced…

General Physics · Physics 2007-05-23 Christopher G Jesudason

Through the consideration of spherically symmetric gravitating systems consisting of perfect fluids with linear equation of state constrained to be in a finite volume, an account is given of the properties of entropy at conditions in which…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Alessandro Pesci