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Related papers: Generalized Holographic Dark Energy and its Observ…

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In this paper, we consider a recently proposed model of Dark Energy (DE) know as Modified Holographic Ricci DE (MHRDE) (which is function of the Hubble parameter and its first derivative with respect to the cosmic time $t$) in the light of…

General Physics · Physics 2017-05-31 Antonio Pasqua , Surajit Chattopadhyay , Iuliia Khomenko

While there is plentiful evidence in all fronts of experimental cosmology for the existence of a non-vanishing dark energy (DE) density \rho_D in the Universe, we are still far away from having a fundamental understanding of its ultimate…

Astrophysics · Physics 2011-07-19 Javier Grande , Ana Pelinson , Joan Sola

Dark energy (DE) models with many free parameters are often considered excessive, as constraining all parameters poses a significant challenge. While such models offer greater flexibility to probe the DE sector in more detail. With the…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-25 Hanyu Cheng , Supriya Pan , Eleonora Di Valentino

We consider a holographic dark energy model, in which both the CC energy density rho_Lambda and the Newton constant G_N are varying quantities, to study the problem of setting an effective field-theory IR cutoff. Assuming that ordinary…

Astrophysics · Physics 2008-11-26 B. Guberina , R. Horvat , H. Nikolic

We investigate the holographic dark energy scenario with a varying gravitational constant in a flat background in the context of Ho\v{r}ava-Lifshitz gravity. We extract the exact differential equation determining the evolution of the dark…

High Energy Physics - Theory · Physics 2014-11-20 M. R. Setare , Mubasher Jamil

We compute the number density of massive Black Holes (BHs) at the centre of galaxies at z=6 in different Dynamical Dark Energy (DDE) cosmologies, and compare it with existing observational lower limits, to derive constraints on the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Alessandra Lamastra , Nicola Menci , Fabrizio Fiore , Cinzia Di Porto , Luca Amendola

A novel fractal structure for the cosmological horizon, inspired by COVID-19 geometry, which results in a modified area entropy, is applied to cosmology in order to serve dark energy. The constraints based on a complete set of observational…

Cosmology and Nongalactic Astrophysics · Physics 2020-09-18 Mariusz P. Dabrowski , Vincenzo Salzano

We consider holographic cosmological models of dark energy in which the infrared cutoff is set by the Hubble's radius. We show that any interacting dark energy model with a matter like term able to alleviate the coincidence problem (i.e.,…

Cosmology and Nongalactic Astrophysics · Physics 2012-07-03 Iván Durán , Luca Parisi

In this work, we consider the cosmological constraints on the holographic Ricci dark energy proposed by Gao et al. [Phys. Rev. D 79, 043511 (2009)], by using the observational data currently available. The main characteristic of holographic…

Cosmology and Nongalactic Astrophysics · Physics 2009-07-29 Xin Zhang

It was argued that the vacuum energy of the Veneziano ghost field of QCD, in a time-dependent background, can be written in the general form, $H + O(H^2)$, where $H$ is the Hubble parameter. Based on this, a phenomenological dark energy…

General Relativity and Quantum Cosmology · Physics 2013-07-24 A. Sheykhi , E. Ebrahimi , Y. Yosefi

Horava gravity has been proposed as a renormalizable, higher-derivative, Lorentz-violating quantum gravity model without ghost problems. A Horava gravity based dark energy (HDE) model for dynamical dark energy has been also proposed earlier…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-11 Eleonora Di Valentino , Nils A. Nilsson , Mu-In Park

Despite the great progress of current cosmological measurements, the nature of the dominant component of the universe, coined dark energy, is still an open question. Early Dark Energy is a possible candidate which may also alleviate some…

Cosmology and Nongalactic Astrophysics · Physics 2015-01-07 Maria Archidiacono , Laura Lopez-Honorez , Olga Mena

R\'enyi Holographic Dark Energy (RHDE) Models has been studied in different dimensions considering a flat FRW metric, subsequently exploring the nature of evolution of different cosmological parameters. It is seen that the number of…

General Relativity and Quantum Cosmology · Physics 2022-02-22 A. Saha , A. Chanda , S. Dey , B. C. Paul , S. Ghose

We investigate a four-parameter entropic dark energy model in a spatially curved FLRW universe, based on a generalized entropy-area relation at the apparent horizon. While the proposed entropy function captures a broad class of…

General Relativity and Quantum Cosmology · Physics 2025-11-21 Davood Momeni

As an update on the initial findings of DESI, the new results provide the first hint of potential deviations from a cosmological constant ($\omega=-1$), which, if confirmed with significance $>(2-4)\sigma$, would challenge the validity of…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-18 Vipin kumar Sharma , Himanshu Chaudhary , Sanved Kolekar

We investigate how the dark energy properties change the cosmological limits on sterile neutrino parameters by using recent cosmological observations. We consider the simplest dynamical dark energy models, the $w$CDM model and the…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-21 Lu Feng , Jing-Fei Zhang , Xin Zhang

We parameterize the equation of state of late-time dark energy as $w_{\mathrm{bin}}(z)$, with three redshift bins, characterized by a constant equation of state in each bin. Then, we constrain the parameters of the $w_{\mathrm{bin}}$CDM…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-28 Ye-Huang Pang , Xue Zhang , Qing-Guo Huang

We perform a comparative study of different types of dynamical dark energy models (DDES) using the cosmographic method. Among the models being examined herein we have the Running Vacuum models (RVMs), which have demonstrated considerable…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-01 Mehdi Rezaei , Joan Sola Peracaula

We are studying the mechanism of the cosmic model in the presence of GGPDE and matter in LRS Bianchi type-I space-time by the utilization of new holographic DE in Saez-Ballester theory. Here we discuss all the data for three scenarios,…

General Physics · Physics 2021-12-15 Priyanka Garg , Archana Dixit , Anirudh Pradhan

In this paper, we use the type Ia supernovae data to constrain the holographic dark energy model proposed by Li. We also apply a cosmic age test to this analysis. We consider in this paper a spatially flat Friedmann-Robertson-Walker…

Astrophysics · Physics 2008-11-26 Xin Zhang , Feng-Quan Wu
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