English
Related papers

Related papers: Expanding Universe: Thermodynamical Aspects From D…

200 papers

A simple and effective approach to thermodynamics is suggested, which solves the major difficulties in the traditional presentation of the subject. The internal energy is introduced from the behavior of deformable bodies, whereas the…

General Physics · Physics 2012-03-13 Rodrigo de Abreu , Vasco Guerra

In this paper we study a model of cosmic evolution, assuming that the different components of the universe could interact between them any time. An effective equation of state (EOS) for the universe has been used as well. A particular…

Cosmology and Nongalactic Astrophysics · Physics 2010-03-17 Alberto C. Balfagon , Raul Ramirez-Satorras

Equation of state (EOS) describes the thermodynamic properties of substances. It has important applications in many fields such as power mechanics, geophysics, astrophysics, and detonation physics. Currently, most EOSs have been constructed…

Statistical Mechanics · Physics 2021-07-15 Ti-Wei Xue , Zeng-Yuan Guo

Thermodynamic properties of matter are conveniently expressed as functional relations between variables known as equations of state. Here we experimentally determine the compressibility, density and pressure equations of state for an…

Quantum Gases · Physics 2016-02-12 K. Fenech , P. Dyke , T. Peppler , M. G. Lingham , S. Hoinka , H. Hu , C. J. Vale

In this paper a study of the accelerated expansion problem of the large scale universe is presented. To derive Friedmann like equations, describing the background dynamics of the recent universe we take into account, that it is possibile to…

General Relativity and Quantum Cosmology · Physics 2017-09-20 M. Khurshudyan , As. Khurshudyan

Foundations of equilibrium thermodynamics are the equation of state (EoS) and four postulated laws of thermodynamics. We use equilibrium thermodynamics paradigms in constructing the EoS for microeconomics system that is a market. This…

General Economics · Economics 2019-07-24 Burin Gumjudpai

It is well known that, in the context of general relativity, an unknown kind of matter that must violate the strong energy condition is required to explain the current accelerated phase of expansion of the Universe. This unknown component…

Cosmology and Nongalactic Astrophysics · Physics 2019-05-22 Ronaldo C. Duarte , Edésio M. Barboza , Everton M. C. Abreu , Jorge Ananias Neto

In this study we consider an exponential decaying form for dark energy as EoS parameter in order to discuss the dynamics of the universe. Firstly, assuming that universe is filled with an ideal fluid which consists of exponential decaying…

General Relativity and Quantum Cosmology · Physics 2015-08-13 Nilay Bostan , Ekrem Aydiner

In a recent article we have introduced Friedmann thermodynamics, where certain geometric parameters in Friedmann models are treated like their thermodynamic counterparts (temperature, entropy, Gibbs potential etc.). This model has the…

General Relativity and Quantum Cosmology · Physics 2008-04-02 Selcuk S. Bayin

We investigate the thermodynamic and phenomenological implications of a cosmological model governed by fractional entropy applied to the apparent horizon of a flat Friedmann-Lema\^{i}tre-Robertson-Walker (FLRW) universe. By utilizing the…

General Relativity and Quantum Cosmology · Physics 2026-04-21 Miguel Cruz , Diego da Silva , Simón González , Samuel Lepe , Joel Saavedra , Manuel Gonzalez-Espinoza

We have investigated the non-static Lorentzian Wormhole model in presence of anisotropic pressure. We have presented some exact solutions of Einstein equations for anisotropic pressure case. Introducing two EoS parameters we have shown that…

General Physics · Physics 2014-11-06 Ujjal Debnath , Mubasher Jamil , R. Myrzakulov , M. Akbar

Thermodynamics on the horizon of a flat universe at late times is studied in holographic cosmological models that assume an associated entropy on the horizon. In such models, a $\Lambda(t)$ model similar to a time-varying $\Lambda(t)$…

General Relativity and Quantum Cosmology · Physics 2020-01-01 Nobuyoshi Komatsu

It exists a large class of systems for which the traditional notion of extensivity breaks down. From experimental examples we induce two general hypothesis concerning such systems. In the first the existence of an internal coordinate system…

Statistical Mechanics · Physics 2015-03-09 J-P. Badiali , A. El Kaabouchi

The pressure, and the energy and entropy densities are determined for the SU(3) gauge theory in $2 + 1$ dimensions from lattice Monte Carlo calculations in the interval $0.6 \leq T/T_c \leq 15$. The finite temperature lattices simulated…

High Energy Physics - Lattice · Physics 2008-11-26 P. Bialas , L. Daniel , A. Morel , B. Petersson

Thermodynamic relations are derived from first principles of mechanics for non-equilibrium processes. Since the key role herein is played by the law of increase of entropy, the latter is analyzed at first. It is shown that its derivation…

chao-dyn · Physics 2008-02-03 J. Kumicak , X. de Hemptinne

Applying Clausius relation with energy-supply defined by the unified first law of thermodynamics formalism to the apparent horizon of a massive cosmological model proposed lately, the corrected entropic formula of the apparent horizon is…

General Relativity and Quantum Cosmology · Physics 2013-04-19 Hui Li , Yi Zhang

The paper is concerned with proving the equivalence of convexity or concavity properties of thermodynamic functions, such as energy and entropy, depending on different sets of variables. These variables are the basic thermodynamic state…

Analysis of PDEs · Mathematics 2025-10-29 Mária Lukáčová-Medvid'ová , Ferdinand Thein , Gerald Warnecke , Yuhuan Yuan

Our aim is to investigate the thermodynamic properties of the universe bounded by the cosmological event horizon and dominated by the tachyon fluid. We give two different laws of evolution of our universe. Further, we show the first law and…

General Relativity and Quantum Cosmology · Physics 2013-10-29 Fei-Quan Tu , Yi-Xin Chen

An irreversible thermodynamical theory of solids is presented where the kinematic quantities are defined in an automatically objective way. Namely, auxiliary elements like reference frame, reference time and reference configuration are…

Classical Physics · Physics 2015-12-22 Tamás Fülöp

We employ the IllustrisTNG simulation data to investigate the turbulent and thermal motions of the cosmic baryonic fluid. With continuous wavelet transform techniques, we define the pressure spectra, or density-weighted velocity power…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-12 Yun Wang , Ping He