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Related papers: Entropy and Wigner Functions

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Quantum Brownian motion model is a typical model in the study of nonequilibrium quantum thermodynamics. Entropy is one of the most fundamental physical concepts in thermodynamics. In this work, by solving the quantum Langevin equation, we…

Quantum Physics · Physics 2021-08-11 Tian Qiu , H. T. Quan

We calculate the Wigner (quasi)probability distribution function of the quantum optical elliptical vortex (QEV), generated by coupling squeezed vacuum states of two modes. The coupling between the two modes is performed by using beam…

Quantum Physics · Physics 2011-04-04 Abir Bandyopadhyay , Shashi Prabhakar , R. P. Singh

In this paper, we review the concept of entropy in connection with the description of quantum unstable systems. We revise the conventional definition of entropy due to Boltzmann and extend it so as to include the presence of complex-energy…

Quantum Physics · Physics 2018-05-09 Osvaldo Civitarese , Manuel Gadella

Here we deconstruct, and then in a reasoned way reconstruct, the concept of "entropy of a system," paying particular attention to where the randomness may be coming from. We start with the core concept of entropy as a COUNT associated with…

General Physics · Physics 2017-05-10 Tommaso Toffoli

A rigorous microscopic theory for the description of quantum-transport phenomena in systems with open boundaries is proposed. We shall show that the application of the conventional Wigner-function formalism to this problem leads to…

Condensed Matter · Physics 2007-05-23 Remo Proietti Zaccaria , Fausto Rossi

For a system randomly prepared in a number of quantum states, we present a lower bound for the distinguishability of the quantum states, that is, the success probability of determining the states in the form of entropy. When the states are…

Quantum Physics · Physics 2015-11-11 Seungho Yang , Jinhyoung Lee , Hyunseok Jeong

It is well known that a Shannon based definition of information entropy leads in the classical case to the Boltzmann entropy. It is tempting to regard the Von Neumann entropy as the corresponding quantum mechanical definition. But the…

Quantum Physics · Physics 2009-11-10 Alexander Stotland , Andrei A. Pomeransky , Eitan Bachmat , Doron Cohen

An extension to computational mechanics complexity measure is proposed in order to tackle quantum states complexity quantification. The method is applicable to any $n-$partite state of qudits through some simple modifications. A Werner…

Computational Physics · Physics 2011-10-28 Yuri Campbell , José Roberto Castilho Piqueira

The Schwinger process in strong electric fields creates particles and antiparticles that are entangled. The entropy of entanglement between particles and antiparticles has been found to be equal to the statistical Gibbs entropy of the…

High Energy Physics - Phenomenology · Physics 2022-11-28 Gerald V. Dunne , Adrien Florio , Dmitri E. Kharzeev

After a brief introduction to the concept of entanglement in quantum systems, I apply these ideas to many-body systems and show that the von Neumann entropy is an effective way of characterising the entanglement between the degrees of…

Statistical Mechanics · Physics 2009-11-13 John Cardy

A method of representing probabilistic aspects of quantum systems is introduced by means of a density function on the space of pure quantum states. In particular, a maximum entropy argument allows us to obtain a natural density function…

Quantum Physics · Physics 2015-06-26 D. C. Brody , L. P. Hughston

The relation between entanglement entropy and the computational difficulty of classically simulating Quantum Mechanics is briefly reviewed. Matrix product states are proven to provide an efficient representation of one-dimensional quantum…

Quantum Physics · Physics 2008-11-26 Jose I. Latorre

We introduce a quantum phase space representation for the orientation state of extended quantum objects, using the Euler angles and their conjugate momenta as phase space coordinates. It exhibits the same properties as the standard Wigner…

Quantum Physics · Physics 2013-06-11 Timo Fischer , Clemens Gneiting , Klaus Hornberger

We present analytical results toward the Wigner entropy conjecture, which posits that among all physical Wigner non-negative states the Wigner entropy is minimized by pure Gaussian states for which it attains the value $1+\ln\pi$.Working…

Quantum Physics · Physics 2026-01-26 Qipeng Qian , Christos Gagatsos

Entropy measures quantify the amount of information and correlation present in a quantum system. In practice, when the quantum state is unknown and only copies thereof are available, one must resort to the estimation of such entropy…

Quantum Physics · Physics 2024-03-27 Ziv Goldfeld , Dhrumil Patel , Sreejith Sreekumar , Mark M. Wilde

The novel concept of quantum logical entropy is presented and analyzed. We prove several basic properties of this entropy with regard to density matrices. We hereby motivate a different approach for the assignment of quantum entropy to…

Quantum Physics · Physics 2017-11-27 Boaz Tamir , Eliahu Cohen

Entropic forces result from an increase of the entropy of a thermodynamical physical system. It has been proposed that gravity is such a phenomenon and many articles have appeared on the literature concerning this problem. Loop quantum…

General Relativity and Quantum Cosmology · Physics 2015-02-20 J. Manuel Garcia-Islas

We study several examples from quantum control theory in the framework of Wigner functions and measures for infinite dimensional open quantum systems. An axiomatic definition of coherent quantum feedback is proposed within this setting.

Mathematical Physics · Physics 2015-05-11 J. E. Gough , T. S. Ratiu , O. G. Smolyanov

Quantum mechanics is derived as an application of the method of maximum entropy. No appeal is made to any underlying classical action principle whether deterministic or stochastic. Instead, the basic assumption is that in addition to the…

Quantum Physics · Physics 2011-05-09 Ariel Caticha

We study the Wigner function for the inflationary tensor perturbation defined in the real phase space. We compute explicitly the Wigner function including the contributions from the cubic self-interaction Hamiltonian of tensor…

High Energy Physics - Theory · Physics 2021-05-19 Jinn-Ouk Gong , Min-Seok Seo