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Related papers: Generalized Ghost Dark Energy in DGP Model

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In this work, we present two generalized formulations of the Holographic and Ricci Dark Energy (DE) models, given by $ \rho_{GH} = 3c^2M^{2}_{pl} \left[ 1-\epsilon\left(1-\frac{R}{H^2}\right) \right]H^2$ and $\rho_{GR} =…

General Relativity and Quantum Cosmology · Physics 2025-10-29 Antonio Pasqua

In this paper we investigate cosmological dynamics on the normal branch of a DGP-inspired scenario within a phase space approach where induced gravity is modified in the spirit of $f(R)$-theories. We apply the dynamical system analysis to…

General Relativity and Quantum Cosmology · Physics 2015-05-19 Kourosh Nozari , Faeze Kiani

Dark energy cosmology is considered in a modified Gauss-Bonnet (GB) model of gravity where an arbitrary function of the GB invariant, $f(G)$, is added to the General Relativity action. We show that such theory is endowed with a quite rich…

High Energy Physics - Theory · Physics 2008-11-26 Guido Cognola , Emilio Elizalde , Shin'ichi Nojiri , Sergei D. Odintsov , Sergio Zerbini

We investigate about the stability of generalized QCD ghost dark energy model against perturbations in the FRW background. For this purpose, we use the squared sound speed $v_s^2$ whose sign determines the stability of the model. We explore…

General Physics · Physics 2015-06-12 Esmaeil Ebrahimi , Ahmad Sheykhi

We investigate the new Tsallis agegraphic dark energy (NTADE) scenario in the framework of Horava-Lifshitz cosmology. Considering interacting and non-interacting scenarios of NTADE with dark matter in a spatially non-flat universe, we…

General Relativity and Quantum Cosmology · Physics 2020-01-22 M. Abdollahi Zadeh

I consider some of the issues we face in trying to understand dark energy. Huge fluctuations in the unknown dark energy equation of state can be hidden in distance data, so I argue that model-independent tests which signal if the…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Chris Clarkson

The Dvali, Gabadadze and Porrati (DGP) model has a self-accelerating solution, the positive branch, where the brane is asymptotically de Sitter. A de Sitter space-time can be seen as a boundary between quintessence-like behaviour and…

Astrophysics · Physics 2008-11-26 Mariam Bouhmadi-Lopez

The evolution of the dark energy parameter within the scope of a spatially homogeneous and isotropic Friedmann-Robertson-Walker (FRW) model filled with perfect fluid and dark energy components is studied by generalizing the recent results…

General Physics · Physics 2014-03-11 Anirudh Pradhan

In this paper we provide a short review of the main results developed in hep-th/0604086. We focus on linearised vacuum perturbations about the self-accelerating branch of solutions in the DGP model. These are shown to contain a ghost in the…

High Energy Physics - Theory · Physics 2008-11-26 Antonio Padilla

Properties of Braneworld models of dark energy are reviewed. Braneworld models admit the following interesting possibilities: (i) The effective equation of state can be w < -1 as well as w > -1. In the former case the expansion of the…

Astrophysics · Physics 2007-05-23 Varun Sahni

We perform a Markov Chain Monte Carlo analysis of the self-accelerating and normal branch of Dvali-Gabadadze-Porrati braneworld gravity. By adopting a parameterized post-Friedmann description of gravity, we utilize all of the cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-15 Lucas Lombriser , Wayne Hu , Wenjuan Fang , Uros Seljak

Confirmation of accelerated expansion of the universe probed the concept of dark energy theory, and since then, numerous models have been introduced to explain its origin and nature. The present work is based on reconstructing dark energy…

General Relativity and Quantum Cosmology · Physics 2023-10-09 Himanshu Chaudhary , Amine Bouali , Ujjal Debnath , Tanusree Roy , G. Mustafa

New measurements of the expansion rate of the Universe have plunged the standard model of cosmology into a severe crisis. In this letter, we propose a simple resolution to the problem that relies on a first order phase transition in a dark…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-24 Florian Niedermann , Martin S. Sloth

In the simplest Higgs phase of gravity called ghost condensation, an accelerating universe with a phantom era (w<-1) can be realized without ghost or any other instabilities. In this paper we show how to reconstruct the potential in the…

High Energy Physics - Theory · Physics 2009-11-11 Shinji Mukohyama

We investigated the effects of bulk scalar field in the braneworld cosmological scenario. The Friedmann equations and acceleration condition in presence of the bulk scalar field for a zero tension brane and cosmological constant are…

General Relativity and Quantum Cosmology · Physics 2011-07-19 Rizwan ul Haq Ansari , P. K. Suresh

The standard cosmological model is in the midst of a stress test, thanks to the tension between supernovae-based measurements of the Hubble constant $H_{0}$ and inferences of its values from Cosmic Microwave Background (CMB) anisotropies.…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-05 K. Rezazadeh , A. Ashoorioon , D. Grin

We generalize the holographic dark energy model described in Hubble length IR cutoff by assuming a slowly time varying function for holographic parameter $c^2$. We calculate the evolution of EoS parameter and the deceleration parameter as…

General Relativity and Quantum Cosmology · Physics 2015-06-11 M. Malekjani

The generalized Chaplygin gas (GCG), is studied in this paper by using the latest observational data including 182 gold sample type Ia supernovae (Sne Ia) data, the ESSENCE Sne Ia data, the distance ratio from $z=0.35$ to $z=1089$ (the…

Astrophysics · Physics 2009-11-10 Puxun Wu , Hongwei Yu

We investigate a kind of holographic dark energy model with the future event horizon the IR cutoff and the equation of state -1. In this model, the constraint on the equation of state automatically specifies an interaction between matter…

Astrophysics · Physics 2007-05-23 Hui Li , Zong-kuan Guo , Yuan-zhong Zhang

Understanding the accelerating expansion of the Universe remains a fundamental challenge in modern cosmology. In this paper, we investigate a cosmological model parametrized by a generalized variable deceleration parameter to elucidate the…

General Relativity and Quantum Cosmology · Physics 2023-09-29 M. Koussour , N. Myrzakulov , Alnadhief H. A. Alfedeel , F. Awad , M. Bennai