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Related papers: Entropic-force dark energy reconsidered

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Very recently, Verlinde considered a theory in which space is emergent through a holographic scenario, and proposed that gravity can be explained as an entropic force caused by changes in the information associated with the positions of…

General Relativity and Quantum Cosmology · Physics 2010-08-17 Hao Wei

Entropic force originates in the assumption that there is a horizon for the universe. This horizon gives rise to additional terms in the equations of motion. Using dynamical system calculations, our results show that in the presence of dark…

General Relativity and Quantum Cosmology · Physics 2020-02-18 Maryam Aghaei Abchouyeh , Behrouz Mirza , Fatemeh Sadeghi

A cosmological model in an Einstein-Cartan framework endowed with torsion is studied. For a torsion function assumed to be proportional to Hubble expansion function, namely $\phi=-\alpha H$, the contribution of torsion function as a dark…

General Relativity and Quantum Cosmology · Physics 2022-04-27 S. H. Pereira , A. M. Vicente , J. F. Jesus , R. F. L. Holanda

Understanding the evolution of dark energy poses a significant challenge in modern cosmology, as it is responsible for the universe's accelerated expansion. In this study, we focus on a specific $f(T)$ cosmological model and analyze its…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-14 A. Zhadyranova , M. Koussour , S. Bekkhozhayev , V. Zhumabekova , J. Rayimbaev

It has been recently proposed that gravity might be an entropic force. Although a well defined fundamental description for such a mechanism is still lacking, it is still possible to address the viability of phenomenological models of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Miguel Zumalacarregui

In this work we apply the gravity-thermodynamics approach for the case of generalized mass-to-horizon entropy, which is a two-parameter extension of Bekenstein-Hawking entropy that arises from the extended mass-to-horizon relation, that is…

General Relativity and Quantum Cosmology · Physics 2025-04-01 Spyros Basilakos , Andreas Lymperis , Maria Petronikolou , Emmanuel N. Saridakis

We examine a cosmological model with a dark energy density of the form $\rho_{DE}(t)=\rho_X(t)+\rho_Z(t)$, where $\rho_X$ is the component that accelerates the Hubble expansion at late times and $\rho_Z(t)$ is an extra contribution…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-22 Michele Maggiore , Lukas Hollenstein , Maud Jaccard , Ermis Mitsou

Within the standard cosmological model, the presence of Dark Energy (DE) is the only structural difference between the early and late times Universe. While its presence is in full display at late times, it is irrelevant at early times,…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-14 Marco Raveri

In a thermodynamical model of cosmological FLRW event horizons for the dark energy (DE), we consider a logarithmic corrective term in the entropy to which corresponds a new term in the DE density. This model of $\Lambda (t)$ in an…

Astrophysics · Physics 2016-08-15 Cécile Barbachoux , Jérome Gariel , Gérard Le Denmat

Numerous upcoming observations, such as WFIRST, BOSS, BigBOSS, LSST, Euclid, and Planck, will constrain dark energy (DE)'s equation of state with great precision. They may well find the ratio of pressure to energy density, $w$, is -1,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Zachary Slepian , J. Richard Gott , Joel Zinn

Dark energy observations may be explained within general relativity using an inhomogeneous Hubble-scale depression in the matter density and accompanying curvature, which evolves naturally out of an Einstein-de Sitter (EdS) model. We…

Cosmology and Nongalactic Astrophysics · Physics 2012-12-10 Sean February , Julien Larena , Mathew Smith , Chris Clarkson

In this paper, applying the Hartman-Grobman theorem we carry out a qualitative late-time analysis of some unified dark energy-matter Friedmann cosmological models, where the two interact through linear energy exchanges, and the dark energy…

General Relativity and Quantum Cosmology · Physics 2020-05-06 Muhsin Aljaf , Daniele Gregoris , Martiros Khurshudyan

We propose a dark energy model based on the physics of critical phenomena which is consistent with both the Planck's CMB and the Riess et al.'s local Hubble measurements. In this model the dark energy density behaves like the magnetization…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-09 Abdolali Banihashemi , Nima Khosravi , Arman Shafieloo

In this paper we study the viability of an entropic cosmological model. The effects of entropic gravity are derived from a modified entropy-area relationship with a volumetric entropy term. This model describes a late time limit cosmic…

General Relativity and Quantum Cosmology · Physics 2024-03-07 Javier Chagoya , I. Díaz-Saldaña , J. C. López-Domínguez , M. Sabido

In this paper, after reconstructing the redshift evolution of the Hubble function by adopting Gaussian process techniques, we estimate the best-fit parameters for some flat Friedmann cosmological models based on a Modified Chaplygin Gas…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-28 Muhsin Aljaf , Daniele Gregoris , Martiros Khurshudyan

We investigate a spatially flat Friedmann-Lema\^itre-Robertson-Walker cosmology in which a decaying vacuum term causes matter production at late times. Assuming a decay proportional to the Hubble rate, the ratio of the background energy…

Cosmology and Nongalactic Astrophysics · Physics 2011-08-26 W. Zimdahl , H. A. Borges , S. Carneiro , J. C. Fabris , W. S. Hipólito-Ricaldi

We obtain the analogues of the Friedman equations in an emergent gravity scenario in the presence of dark energy. The background metric is taken to be Friedman-Lemaitre-Robertson-Walker (FLRW). We show that if $\dot\phi ^{2}$ is the dark…

General Relativity and Quantum Cosmology · Physics 2015-02-24 Debashis Gangopadhyay , Goutam Manna

Among various scenarios to explain the acceleration of the universe expansion, the holographic dark energy (HDE) model has got a lot of enthusiasm recently. In the derivation of holographic energy density, the area relation of the black…

General Physics · Physics 2011-09-28 Ahmad Sheykhi , Mubasher Jamil

Phenomena currently attributed to Dark Energy (DE) and Dark Matter (DM) are merely a result of the interplay between gravitational energy density, generated by the contraction of space by matter, and the energy density of the Cosmological…

Astrophysics · Physics 2008-12-25 Shlomo Barak , Elia M Leibowitz

The Hubble Constant measured from the anisotropy in the cosmic microwave background (CMB) is shown to be independent of small changes from the standard model of the redshift dependence of dark energy. Modifications of the Friedmann equation…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Jeremy Mould