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Related papers: Virialization in Dark Energy Cosmology

200 papers

We develop here a relatively simple description of dark energy based on the dynamics of non-minimally coupled to gravity phantom scalar field which, in limit, corresponds to cosmological constant. The dark energy equation of state, obtained…

Astrophysics · Physics 2014-11-18 Aleksandra Kurek , Orest Hrycyna , Marek Szydlowski

We propose a method to relate the holographic minimal information density to the de Broglie's wavelength at a given universe temperature $T$. To figure this out, we assume that the thermal length of massive and massless constituents…

General Relativity and Quantum Cosmology · Physics 2017-07-11 Orlando Luongo

We propose a new Dark Energy parametrization based on the dynamics of a scalar field. We use an equation of state $w=(x-1)/(x+1)$, with $x=E_k/V$, the ratio of kinetic energy $E_k=\dot\phi^2/2$ and potential $V$. The eq. of motion gives…

Cosmology and Nongalactic Astrophysics · Physics 2011-12-09 Axel de la Macorra

Motivated by the recent observations for the cosmic acceleration and the suitable evolution of the Universe provided an interaction (decay of dark energy to matter) is incorporated in a cosmological model, we study the cosmological…

High Energy Physics - Theory · Physics 2009-03-24 M. R. Setare , Elias C. Vagenas

Most parameterizations of the dark energy equation of state do not reflect realistic underlying physical models. Here, we develop a relatively simple description of dark energy based on the dynamics of a scalar field which is exact in the…

Astrophysics · Physics 2008-11-26 Robert Crittenden , Elisabetta Majerotto , Federico Piazza

The "lost" information of black hole through the Hawking radiation was discovered being stored in the correlation among the non-thermally radiated particles [Phys. Rev. Lett 85, 5042 (2000), Phys. Lett. B 675, 1 (2009)]. This correlation…

General Relativity and Quantum Cosmology · Physics 2018-05-22 Yu-Han Ma , Jin-Fu Chen , Chang-Pu Sun

In this work we explore the scope of two holographic dark energy models within the interacting scenario for the dark sector and spatial curvature. For one holographic model we consider the usual formula for the dark energy density with the…

General Relativity and Quantum Cosmology · Physics 2023-05-10 Azucena Bolaños , Miguel Cruz , Samuel Lepe , David Rogelio Márquez-Castillo

We investigate how the nature of dark energy affects the determination of the curvature of the universe from recent observations. For this purpose, we consider the constraints on the matter and dark energy density using observations of type…

Astrophysics · Physics 2008-11-26 Kazuhide Ichikawa , Masahiro Kawasaki , Toyokazu Sekiguchi , Tomo Takahashi

This study examines the gravitational collapse of an overdense dark matter region in a coupled scalar field dark energy scenario within a flat FLRW background. It finds that, depending on the initial conditions, some overdense regions avoid…

General Relativity and Quantum Cosmology · Physics 2026-02-10 Priyanka Saha , Dipanjan Dey , Kaushik Bhattacharya

Gravitational collapse of a shell of charged dust surrounded by the phantom dark energy is probed by the minimal area surface, which is dual to probe the thermalization in the boundary quantum field by expectation values of Wilson loop in…

High Energy Physics - Theory · Physics 2016-12-28 Xiao-Xiong Zeng , Xin-Yun Hu , Li-Fang Li

It has, quite recently, become fashionable to study a certain class of holographic-inspired models for the dark energy. These investigations have, indeed, managed to make some significant advances towards explaining the empirical data.…

High Energy Physics - Theory · Physics 2009-02-18 A. J. M. Medved

Infrared observations of Sgr A$^*$ and M87$^*$ are incompatible with the assumption that these sources have physical surfaces in thermal equilibrium with their accreting environments. In this paper we discuss a general parametrization of…

High Energy Astrophysical Phenomena · Physics 2023-07-03 Raúl Carballo-Rubio , Francesco Di Filippo , Stefano Liberati , Matt Visser

We investigate the impact on the classical dynamics of dark matter particles and dark energy of a non-minimal coupling in the dark sector, assuming that the mass of the dark matter particles is coupled to a dark energy scalar field. We show…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-06 P. P. Avelino

We show the way of dark matter and dark energy presentation via ansatzs on the kinetic energies of the fields in the two-component chiral cosmological model. To connect a kinetic interaction of dark matter and dark energy with observational…

General Relativity and Quantum Cosmology · Physics 2014-04-24 Renat R. Abbyazov , Sergey V. Chervon

In this work, we introduce a parametrization of early dark energy that mimics radiation at early times and governs the present acceleration of the Universe. We show that such parametrization models non-linear electrodynamics in the early…

General Relativity and Quantum Cosmology · Physics 2023-07-13 H. B. Benaoum , Luz Ángela García , Leonardo Castañeda

Using the Tsallis generalized entropy, holographic hypothesis and also considering the Hubble horizon as the IR cutoff, we build a holographic model for dark energy and study its cosmological consequences in the Brans-Dicke framework. At…

General Relativity and Quantum Cosmology · Physics 2018-09-05 S. Ghaffari , H. Moradpour , I. P. Lobo , J. P. Morais Graça , Valdir B. Bezerra

The existence of dark matter and dark energy in cosmology is implied by various observations, however, they are still unclear because they have not been directly detected. In this Letter, an unified model of dark energy and dark matter that…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-27 Jiro Matsumoto

Formation of halos in the Dark Ages from initial spherical perturbations is analyzed in a four component Universe (dark matter, dark energy, baryonic matter and radiation) in the approximation of relativistic hydrodynamics. Evolution of…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-29 Bohdan Novosyadlyj , Valerii Shulga , Wei Han , Yurij Kulinich , Maxym Tsizh

We develop a simple method of dark energy reconstruction using a geometrical form of the luminosity-distance relation. In this method the FRW dynamical system with dark energy is reconstructed instead of the equation of state parameter. We…

Astrophysics · Physics 2017-09-29 Marek Szydlowski , Aleksandra Kurek

In this letter, we consider the possibility of reconciling metric theories of gravitation with violation of the conservation of energy-momentum. Under some circumstances, this can be achieved in the context of unimodular gravity, and it…

General Relativity and Quantum Cosmology · Physics 2017-01-18 Thibaut Josset , Alejandro Perez , Daniel Sudarsky