English
Related papers

Related papers: Moderate Degree of Input Negative Entropy Flow and…

200 papers

The concept of entropy in nonequilibrium macroscopic systems is investigated in the light of an extended equation of motion for the density matrix obtained in a previous study. It is found that a time-dependent information entropy can be…

Statistical Mechanics · Physics 2009-11-10 W. T. Grandy

Do negative absolute temperatures matter physics and specifically Statistical Physics? We provide evidence that we can certainly answer positively to this vexata quaestio. The great majority of models investigated by statistical mechanics…

Statistical Mechanics · Physics 2021-07-07 Marco Baldovin , Stefano Iubini , Roberto Livi , Angelo Vulpiani

We discuss the energy density,temperature and entropy of dark matter (DM) and dark energy (DE) as functions of the scale factor $a$ in an expanding universe. In a model of non-interacting dark components we repeat a derivation from…

General Relativity and Quantum Cosmology · Physics 2017-03-27 Z. Haba

Entropy is the distinguishing and most important concept of our efforts to understand and regularize our observations of a very large class of natural phenomena, and yet, it is one of the most contentious concepts of physics. In this…

Quantum Physics · Physics 2007-05-23 Elias P. Gyftopoulos

The laws of thermodynamics, despite their wide range of applicability, are known to break down when systems are correlated with their environments. Here, we generalize thermodynamics to physical scenarios which allow presence of…

Quantum Physics · Physics 2018-02-06 Manabendra Nath Bera , Arnau Riera , Maciej Lewenstein , Andreas Winter

Traditional form of the second law of thermodynamics is strongly restricted by three conditions: One is the initial joint state of the system and surroundings should be a product state, so that there exists no initial correlations. The…

Quantum Physics · Physics 2018-03-19 Ke-Xia Jiang , Yuan-Mou Li , Heng Fan

During the past dozen years there have been numerous articles on a relation between entropy and probability which is non-additive and has a parameter $q$ that depends on the nature of the thermodynamic system under consideration. For $q=1$…

Statistical Mechanics · Physics 2009-11-07 Michael Nauenberg

In the expanding universe, two interacting fields are no longer in thermal contact when the interaction rate becomes smaller than the Hubble expansion rate. After decoupling, two subsystems are usually treated separately in accordance with…

High Energy Physics - Theory · Physics 2017-12-20 Yuichiro Nakai , Noburo Shiba , Masaki Yamada

The proper definition of entropy is fundamental to the relationship between statistical mechanics and thermodynamics. It also plays a major role in the recent debate about the validity of the concept of negative temperature. In this paper,…

Statistical Mechanics · Physics 2015-11-18 Robert H. Swendsen

The entropy of a thermally isolated system should not decrease after a quench or external driving. For a classical system following Hamiltonian dynamics, we show how this statement emerges for a large system in the sense that the extensive…

Statistical Mechanics · Physics 2020-12-24 Udo Seifert

We formulate a geometric framework in which physical laws emerge from restricted access to microscopic information. Measurement constraints are modeled as a gauge symmetry acting on density operators, inducing a gauge-reduced space of…

Quantum Physics · Physics 2026-05-19 Tiago Pernambuco , Lucas Chibebe Céleri

The physical foundations of a variety of emerging technologies --- ranging from the applications of quantum entanglement in quantum information to the applications of nonequilibrium bulk and interface phenomena in microfluidics, biology,…

Quantum Physics · Physics 2014-03-25 Gian Paolo Beretta , Enzo Zanchini

We analyze cosmology assuming unitary quantum mechanics, using a tripartite partition into system, observer and environment degrees of freedom. This generalizes the second law of thermodynamics to "The system's entropy can't decrease unless…

High Energy Physics - Theory · Physics 2013-05-30 Max Tegmark

According to the second law of thermodynamics, the arrow of time points to an ever increasing entropy of the Universe. However, exactly how the entropy evolves with time and what drives the growth remain largely unknown. Here, for the first…

Cosmology and Nongalactic Astrophysics · Physics 2012-11-09 Xinghai Zhao , Yuexing Li , Qirong Zhu , Derek Fox

The frequent misunderstanding of information entropy is pointed out. It is shown that, contrary to fortuitous situations and common beliefs, there is no general interrelation between the information entropy and the thermodynamical entropy.…

General Physics · Physics 2017-07-19 Laszlo B. Kish , David K. Ferry

This paper is a non-technical, informal presentation of our theory of the second law of thermodynamics as a law that is independent of statistical mechanics and that is derivable solely from certain simple assumptions about adiabatic…

Mathematical Physics · Physics 2009-10-31 Elliott H. Lieb , Jakob Yngvason

The 2nd law of thermodynamics yields an irreversible increase in entropy until thermal equilibrium is achieved. This irreversible increase is often assumed to require large and complex systems to emerge from the reversible microscopic laws…

Statistical Mechanics · Physics 2023-11-21 Ralph V. Chamberlin

Information plays an important role in our understanding of the physical world. We hence propose an entropic measure of information for any physical theory that admits systems, states and measurements. In the quantum and classical world,…

Quantum Physics · Physics 2010-05-04 Anthony J. Short , Stephanie Wehner

The physical meaning of entropy is analyzed in the context of statistical, nuclear, atomic physics and cosmology. Only the microcanonical Boltzmann entropy leads to no contradictions in several simple, elementary and for thermodynamics…

Nuclear Theory · Physics 2007-05-23 D. H. E. Gross

The stochastic entropy generated during the evolution of a system interacting with an environment may be separated into three components, but only two of these have a non-negative mean. The third component of entropy production is…

Statistical Mechanics · Physics 2013-05-30 Ian J. Ford , Richard E. Spinney