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Related papers: On Phantom Thermodynamics

200 papers

This work is focused on the exploration of the thermodynamics foundations of the matter creation scenario when a generalized form of the second law of thermodynamics for this scheme is implemented. In this scenario we consider an expanding…

General Relativity and Quantum Cosmology · Physics 2024-07-23 Víctor H. Cárdenas , Miguel Cruz , Samuel Lepe

We examine phantom dark energy models derived from a scalar field with a negative kinetic term for which V(phi) approaches infinity asymptotically. All such models can be divided into three classes, corresponding to an equation of state…

Astrophysics · Physics 2009-11-11 Jens Kujat , Robert J. Scherrer , A. A. Sen

Adopting the thin-layer improved brick-wall method, we investigate the thermodynamics of a black hole embedded in a spatially flat Friedmann-Robertson-Walker universe. We calculate the temperature and the entropy at every apparent horizon…

General Relativity and Quantum Cosmology · Physics 2011-03-07 Khireddine Nouicer

Models of dark energy are conveniently characterized by the equation-of-state parameter w=p/\rho, where \rho is the energy density and p is the pressure. Imposing the Dominant Energy Condition, which guarantees stability of the theory,…

Astrophysics · Physics 2011-05-12 Sean M. Carroll , Mark Hoffman , Mark Trodden

The fractional dark energy (FDE) model describes the accelerated expansion of the Universe through a nonrelativistic gas of particles with a noncanonical kinetic term. This term is proportional to the absolute value of the three-momentum to…

General Relativity and Quantum Cosmology · Physics 2022-03-21 Ricardo G. Landim

Thermodynamic analyses of dark energy as a relativistic fluid indicates that this intriguing component of the universe mimics a bulk viscous pressure when the parameter of its barotropic equation of state varies with time. Since in…

General Relativity and Quantum Cosmology · Physics 2025-03-04 José Medeiros da Costa Netto , Heydson Henrique Brito da Silva

We consider the thermodynamic properties of a rotating gas of fermions. We begin by constructing the thermodynamic potential $\Phi$ and its associated current $\phi^\mu$ within the grand canonical ensemble of a macroscopic rigidly rotating…

High Energy Physics - Theory · Physics 2025-09-23 Victor E. Ambrus , Aleksandar Gecić

The concept of negative temperature has recently received renewed interest in the context of debates about the correct definition of the thermodynamic entropy in statistical mechanics. Several researchers have identified the thermodynamic…

Statistical Mechanics · Physics 2016-03-08 Robert H. Swendsen , Jian-Sheng Wang

The thermodynamics of ideal gas on the noncommutative geometry in the coherent state formalism is investigated. We first evaluate the statistical interparticle potential and see that there are residual "attraction (repulsion) potential"…

High Energy Physics - Theory · Physics 2009-01-16 Wung-Hong Huang , Kuo-Wei Huang

Recent analysis of the observation data indicates that the equation of state of the dark energy might be smaller than -1, which leads to the introduction of phantom models featured by its negative kinetic energy to account for the regime of…

High Energy Physics - Theory · Physics 2009-11-10 Jian-gang Hao , Xin-zhou Li

Abandoning the perfect fluid hypothesis, we investigate here the possibility that the dark energy equation of state (EoS) $w$ is a nonlinear function of the energy density $\rho$. To this aim, we consider four different EoS describing…

Astrophysics · Physics 2009-11-13 V. F. Cardone , C. Tortora , A. Troisi , S. Capozziello

We propose a new equation of state for the Dark Energy component of the Universe. It is modeled on the equation of state $p=w(\rho-\rho_{*})$ which can describe a liquid, for example water. We show that its energy density naturally…

Astrophysics · Physics 2007-05-23 Richard Holman , Siddartha Naidu

We examine phantom dark energy models produced by a field with a negative kinetic term and a potential that satisfies the slow roll conditions: [(1/V)(dV/dphi)]^2 << 1 and (1/V)(d^2 V/dphi^2) << 1. Such models provide a natural mechanism to…

Astrophysics · Physics 2008-11-26 Robert J. Scherrer , A. A. Sen

We investigate the validity of the generalized second law of thermodynamics, in the cosmological scenario where dark energy interacts with both dark matter and radiation. Calculating separately the entropy variation for each fluid component…

High Energy Physics - Theory · Physics 2010-07-20 Mubasher Jamil , Emmanuel N. Saridakis , M. R. Setare

By the assumption that the thermodynamics second law is valid, we study the possibility of $\omega=-1$ crossing in interacting holographic dark energy model. Depending on the choice of the horizon and the interaction, the transition from…

General Relativity and Quantum Cosmology · Physics 2008-11-26 H. Mohseni Sadjadi , M. Honardoost

In this paper, at first, we focus on a FRW universe in which the dark energy candidate satisfies the Polytropic equation of state and study thermodynamics of dark energy. Bearing the thermal fluctuation theorem in mind, we establish a…

General Relativity and Quantum Cosmology · Physics 2016-06-07 H. Moradpour , M. T. Mohammadi Sabet

We consider late-time cosmology in a (phantom) scalar-tensor theory with an exponential potential, as a dark energy model with equation of state parameter close to -1 (a bit above or below this value). Scalar (and also other kinds of)…

High Energy Physics - Theory · Physics 2009-09-17 Emilio Elizalde , Shin'ichi Nojiri , Sergei D. Odintsov

We study the thermodynamics of the universe containing perfect fluid with equation of state $p=\omega\rho,\omega$ is variable. Here we choose $\omega$ to be a function of the red shift variable $z$ and four different choices of $\omega$ has…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Nairwita Mazumder , Subenoy Chakraborty

Motivated by some earlier works \cite{pavon,sadjadi} dealing with the study of generalized second law (GSL) of thermodynamics for a system comprising of a Schwarzschild black accreting a test non-self-gravitating fluid namely phantom energy…

General Relativity and Quantum Cosmology · Physics 2012-07-17 Mubasher Jamil , D. Momeni , Kazuharu Bamba , Ratbay Myrzakulov

We investigate a family of inhomogeneous and anisotropic gravitational fields exhibiting a future singularity at a finite value of the proper time. The studied spherically symmetric spacetimes are asymptotically Friedmann-Robertson-Walker…

General Relativity and Quantum Cosmology · Physics 2015-06-15 Mauricio Cataldo , Paola Meza