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Related papers: Ghost dark energy in the DGP braneworld

200 papers

We study the phase space asymptotics of the so called Veneziano ghost dark energy models. Models where the ghost field's energy density: i) $\rho_{ghost}\propto H$, and ii) $\rho_{ghost}\propto H+H^2$, are investigated. Both, cases with and…

General Relativity and Quantum Cosmology · Physics 2012-11-16 Ricardo Garcia-Salcedo , Tame Gonzalez , Israel Quiros

I briefly review our current understanding of dark matter and dark energy. The first part of this paper focusses on issues pertaining to dark matter including observational evidence for its existence, current constraints and the `abundance…

Astrophysics · Physics 2022-07-19 Varun Sahni

In this work we explore the background dynamics when dark energy is coupled to dark matter with a suitable interaction in the universe described by brane cosmology. Here DGP and the RSII brane models have been considered separately. Dark…

General Physics · Physics 2015-06-05 Prabir Rudra

In this study, we will look at an interacting dark energy model. In the framework of Friedmann-Robertson-Walker (FRW) space-time, we have made the hypothesis of an interacting scheme between two fields (dark matter (DM) and dark energy…

General Relativity and Quantum Cosmology · Physics 2023-11-27 J. K. Singh , Ritika Nagpal

Two variable $\Lambda$ models, viz. $\Lambda \sim (\dot a/a)^2$ and $\Lambda \sim \rho$ have been studied under the assumption that the equation of state parameter $\omega$ is a function of time. The selected $\Lambda$ models are found to…

General Relativity and Quantum Cosmology · Physics 2010-05-07 Utpal Mukhopadhyay , Saibal Ray , Farook Rahaman

For non-flat universe of $k\not=0$, we investigate a model of the interacting holographic dark energy with cold dark matter (CDM). There exists a mixture of two components arisen from decaying of the holographic dark energy into CDM. In…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Kyong Hee Kim , Hyung Won Lee , Yun Soo Myung

We study the interacting dark energy model with time varying dark energy equation of state. We examine the stability in the perturbation formalism and the degeneracy among the coupling between dark sectors, the time-dependent dark energy…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Xiao-Dong Xu , Jian-Hua He , Bin Wang

We study the evolution of the dark energy parameter within the scope of a spatially non-flat and isotropic Friedmann-Robertson-Walker (FRW) model filled with barotropic fluid and bulk viscous stresses. We have obtained cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Hassan Amirhashchi , Anirudh Pradhan , Hishamuddin Zainuddin

We explore the properties of dark energy models for which the equation-of-state, w, defined as the ratio of pressure to energy density, crosses the cosmological-constant boundary w = -1. We adopt an empirical approach, treating the dark…

Astrophysics · Physics 2010-04-06 Robert R. Caldwell , Michael Doran

A proposal to study the original and new agegraphic dark energy in DGP braneworld cosmology is presented in this work. To verify our model with the observational data, the model is constrained by a variety of independent measurements such…

General Relativity and Quantum Cosmology · Physics 2016-06-08 H. Farajollahi , A. Ravanpak , G. F. Fadakar

The braneworld model proposed by Dvali, Gabadadze and Porrati leads to an accelerated universe without cosmological constant or other form of dark energy. Nevertheless, we have investigated the consequences of this model when an holo-…

General Relativity and Quantum Cosmology · Physics 2015-05-30 Norman Cruz , Samuel Lepe , Francisco Peña

Observations exploring the contemporary cosmic acceleration have sparked interest in dark energy models possessing equations of state with w < -1. We review how the cosmic expansion history of a Dvali-Gabadadze-Porrati (DGP) braneworld…

Astrophysics · Physics 2011-07-18 Arthur Lue , Glenn D. Starkman

The paper brings a novel approach to unification of dark matter and dark energy in terms of a cosmic fluid. A model is introduced in which the cosmic fluid speed of sound squared is defined as a function of its equation of state (EoS)…

General Relativity and Quantum Cosmology · Physics 2019-08-06 Dalibor Perkovic , Hrvoje Stefancic

We consider the agegraphic models of dark energy in a braneworld scenario with brane-bulk energy exchange. We assume that the adiabatic equation for the dark matter is satisfied while it is violated for the agegraphic dark energy due to the…

General Relativity and Quantum Cosmology · Physics 2010-04-29 Ahmad Sheykhi

Within the framework of spatially covariant theories, we propose a general model for dark energy (DE) in which the cosmological background and perturbations are independently controlled by different sets of coefficients, and the equation of…

General Relativity and Quantum Cosmology · Physics 2025-08-05 Zhibang Yao , Gen Ye , Alessandra Silvestri

We show that an interaction between dark matter and dark energy generically results in an effective dark energy equation of state of w<-1. This arises because the interaction alters the redshift-dependence of the matter density. An observer…

Astrophysics · Physics 2010-03-26 Subinoy Das , Pier Stefano Corasaniti , Justin Khoury

A new model of dark energy namely "ghost dark energy model" has recently been suggested to interpret the positive acceleration of cosmic expansion. The energy density of ghost dark energy is proportional to the hubble parameter. In this…

General Relativity and Quantum Cosmology · Physics 2015-06-04 M. Malekjani , A. Khodam-Mohammadi

This paper explores the generalized ghost dark energy model in the framework of $f(\textsl{Q}, \textsl{L}_{m})$ gravity, where $\textsl{Q}$ represents the non-metricity scalar and $\textsl{L}_{m}$ denotes the matter-Lagrangian density. We…

General Relativity and Quantum Cosmology · Physics 2025-01-03 M. Zeeshan Gul , M. Sharif , Shan Ali Qureshi , Baiju Dayanandan

In this paper, we study the new Tsallis agegraghic dark energy model in the context of fractal cosmology. The different cosmic implications such as statefinder diagnosis, cosmological plane and squared of sound speed in both interacting and…

General Relativity and Quantum Cosmology · Physics 2024-01-17 M. Abdollahi Zadeh

We investigated a possible interaction between cold dark matter and dark energy, corresponding to a well-known interacting dark energy model discussed in the literature within the context of resolving the Hubble tension. We put constraints…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-21 David Benisty , Supriya Pan , Denitsa Staicova , Eleonora Di Valentino , Rafael C. Nunes