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Related papers: Generalized Semi-Holographic Universe

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In the original holographic dark energy (HDE) model, the dark energy density is proposed to be $\rho_{de} = 3c^2M^2_{pl}L^{-2}$, with $c$ is a dimensionless constant characterizing the properties of the HDE. In this work, we propose the…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-25 Zhenhui Zhang , Miao Li , Xiao-Dong Li , Shuang Wang , Wen-Shuai Zhang

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 analyse the cosmological evolution of a generalised axion-like field that drives the late-time acceleration of the Universe. This model can exhibit tracking behaviour, which alleviates the coincidence problem. The cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-29 Carlos G. Boiza , Mariam Bouhmadi-López

We study the model for holographic dark energy in a spatially closed universe, generalizing the proposal in hep-th/0403127 for a flat universe. We provide independent arguments for the choice of the parameter $c=1$ in the holographic dark…

Astrophysics · Physics 2009-11-10 Qing-Guo Huang , Miao Li

We discuss some cosmological consequences of a general model of coupled quintessence in which the phenomenological coupling between the cold dark matter and dark energy is a function of the cosmic scale factor $\epsilon(a)$. This class of…

Cosmology and Nongalactic Astrophysics · Physics 2010-12-23 F. E. M. Costa

We consider a cosmology in which the final stage of the Universe is neither accelerating nor decelerating, but approaches an asymptotic state where the scale factor becomes a constant value. In order to achieve this, we first bring in a…

General Relativity and Quantum Cosmology · Physics 2015-05-27 Seyen Kouwn , Joohan Lee , Tae Hoon Lee , Taeyoon Moon , Phillial Oh

We propose a cosmological model that makes a significant step toward solving the coincidence problem of the near similarity at the present of the dark energy and dark matter components. Our cosmology has the following properties: a) among…

Astrophysics · Physics 2008-11-26 Luca Amendola , Domenico Tocchini-Valentini

The introduction of an interaction for dark energy to the standard cosmology offers a potential solution to the cosmic coincidence problem. We examine the conditions on the dark energy density that must be satisfied for this scenario to be…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Micheal S. Berger , Hamed Shojaei

In cosmic holography, the fundamental quantity is the degrees of freedom on a horizon surface rather than the material contents within the volume. That is, the horizon area and hence cosmological expansion rate H is related to the entropy.…

High Energy Physics - Theory · Physics 2007-05-23 Eric V. Linder

We construct a holographic dark energy scenario based on Kaniadakis entropy, which is a generalization of Boltzmann-Gibbs entropy that arises from relativistic statistical theory and is characterized by a single parameter $K$ which…

General Relativity and Quantum Cosmology · Physics 2022-06-01 Niki Drepanou , Andreas Lymperis , Emmanuel N. Saridakis , Kuralay Yesmakhanova

We discuss a model of the universe where dark energy is replaced by electrically-charged extremely-massive dark matter. The cosmological constant has a value of the same order as the mean matter density, consistent with observations, and is…

General Physics · Physics 2026-01-26 Paul H. Frampton

We use two simple independent gedankan experiments to show that the holographic principle can be understood intuitively as having its origin in the quantum fluctuations of spacetime. Applied to cosmology, this consideration leads to a…

General Relativity and Quantum Cosmology · Physics 2017-06-28 Y. Jack Ng

A cosmological model of dark energy interacting with dark matter and another general component of the universe is investigated. We found general constraints on these models imposing an accelerated expansion. The same is also studied in the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Norman Cruz , Samuel Lepe , Francisco Pena

In this article we apply the holographic principle for describing in a unifying way the early and the late-time universe, when the general equation of state contains a bulk viscosity. We use the idea of a generalized cut-off holographic…

General Relativity and Quantum Cosmology · Physics 2022-06-24 I. Brevik , A. V. Timoshkin

The two dark sectors of the universe - dark matter and dark energy - may interact with each other. Background and linear density perturbation evolution equations are developed for a generic coupling. We then establish the general conditions…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-25 M. B. Gavela , D. Hernandez , L. Lopez Honorez , O. Mena , S. Rigolin

We construct $(m,n)$-type holographic dark energy models at a phenomenological level, which can be viewed as a generalization of agegraphic models with the conformal-like age as the holographic characteristic size. For some values of…

General Relativity and Quantum Cosmology · Physics 2013-09-19 Yi Ling , Wen-Jian Pan

The semi-classical approach to the quantum geometrodynamical model is used for the description of the properties of the universe on extremely small spacetime scales. Quantum theory for a homogeneous, isotropic and closed universe is…

General Relativity and Quantum Cosmology · Physics 2009-10-21 V. E. Kuzmichev , V. V. Kuzmichev

In the holographic description of cosmic preheating proposed in an accompanied Letter [1], the energy transfer between the inflaton and matter field at strong coupling is suggested to be mimicked by superfluid and normal components of a…

High Energy Physics - Theory · Physics 2021-04-07 Yi-Fu Cai , Shu Lin , Junyu Liu , Jia-Rui Sun

Energy transfer in the dark sector of the universe gives rise to new phenomena of special interest in modern cosmology. When dark energy is modeled as a phantom scalar field, interactions become crucial to avoid Big Rip singularities. In…

General Relativity and Quantum Cosmology · Physics 2025-01-17 Genly Leon , Daya Shankar , Amlan Halder , Andronikos Paliathanasis

Two cosmological models with non-phantom matter having the same expansion of the universe as phantom cosmologies are constructed. The first model is characterized by the evolving gravitational "constant" $G$ and a dark energy component with…

Astrophysics · Physics 2009-11-10 Hrvoje Stefancic
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