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Related papers: Generalized ghost dark energy in Brans-Dicke theor…

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We study the holographic dark energy model in a generalized scalar tensor theory. In a universe filled with cold dark matter and dark energy, the effect of potential of the scalar field is investigated in the equation of state parameter. We…

General Relativity and Quantum Cosmology · Physics 2009-02-18 Yousef Bisabr

In the present work we have studied some features of the generalized Brans-Dicke (BD) model in which the scalar field is allowed to couple non-minimally with matter sector. Extended holographic Ricci dark energy (EHRDE) has been considered…

General Relativity and Quantum Cosmology · Physics 2013-11-14 Surajit Chattopadhyay

In this paper we consider an holographic model of dark energy, where the length scale is the Hubble radius, in a non flat geometry. The model contains the possibility to alleviate the cosmic coincidence problem, and also incorporate a…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Victor H. Cardenas , Roberto G. Perez

The thermodynamic properties of dark energy-dominated universe in the presence of a black hole are investigated in the general case of a varying equation-of-state-parameter $w(a)$. We show that all the thermodynamics quantities are regular…

General Relativity and Quantum Cosmology · Physics 2015-03-14 Khireddine Nouicer

A cosmological model of an holographic dark energy interacting with dark matter throughout a decaying term of the form $Q=3(\lambda_1\rho_{DE} + \lambda_2\rho_m) H$ is investigated. General constraint on the parameters of the model are…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Norman Cruz , Samuel Lepe , Francisco Pena , Joel Saavedra

Recently there has been reports of finding a lower bound on the neutrino mass parameter ($\Sigma m_\nu$) when using ACT and SPTpol data however these bounds on the $\Sigma m_\nu$ are still weaker for most case around at 1 $\sigma$ level. In…

Cosmology and Nongalactic Astrophysics · Physics 2022-08-04 Ravi Kumar Sharma , Kanhaiya Lal Pandey , Subinoy Das

In this paper, spatially homogeneous and anisotropic Bianchi type-I cosmological models of Brans-Dicke theory of gravitation are investigated. The model represents accelerating universe at present and is considered to be dominated by dark…

General Physics · Physics 2021-08-02 Umesh Kumar Sharma , Gopi Kant Goswami , Anirudh Pradhan

The proposal of pilgrim dark energy is based on the speculation that phantom-like dark energy possesses enough resistive force to preclude the black hole formation in the later universe. We explore this phenomenon by assuming the…

General Relativity and Quantum Cosmology · Physics 2015-06-22 M. Sharif , Abdul Jawad

We study dark energy through the viewpoints of parametric and nonparametric analyses of late-time cosmological data. We consider four Hubble parameter priors reflecting the Hubble tension and make use of two phenomenological functions,…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-27 Reginald Christian Bernardo , Daniela Grandón , Jackson Levi Said , Víctor H. Cárdenas

In the current era of precision cosmology, the persistence of cosmological tensions, most notably the Hubble tension and the $S_8$ tension, challenges the standard $\Lambda$CDM model. To reconcile these tensions via late-time modifications…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-18 Yashi Tiwari , Ujjwal Upadhyay , Rajeev Kumar Jain

Despite the significant accomplishments of general relativity, numerous unresolved issues persist in our understanding of the cosmos. One of the most perplexing challenges is the ongoing accelerated expansion of the Universe, which…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-22 M. Koussour , N. Myrzakulov , Alnadhief H. A. Alfedeel , Amare Abebe

In this work we perform some studies related to dark energy. Firstly, we propose a dynamical approach to explain the dark energy content of the universe. We assume that a massless scalar field couples to the Hubble parameter with some…

High Energy Physics - Phenomenology · Physics 2009-01-07 Fei Wang , Jin Min Yang

The Finsler-Randers space-time offers a novel perspective on cosmic dynamics, departing from the constraints of General Relativity. This paper thoroughly investigates two dark energy models resulting from the parametrization of $H$ within…

General Relativity and Quantum Cosmology · Physics 2024-07-04 Z. Nekouee , Himanshu Chaudhary , S. K. Narasimhamurthy , S. K. J. Pacif , Manjunath Malligawad

In the present paper, we investigate the dark energy equation of state using the Gaussian processes analysis method, without confining a particular parametrization. The reconstruction is carried out by adopting the background data including…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-11 Ming-Jian Zhang , Hong Li

With due consideration of reasonable cosmological assumptions within the limit of the present cosmological scenario, we have analysed a spherically symmetric metric in 5D setting within the framework of Lyra manifold. The model universe is…

General Relativity and Quantum Cosmology · Physics 2020-11-25 Pheiroijam Suranjoy Singh , Kangujam Priyokumar Singh

We add a new scalar field in the no-scale Brans-Dicke gravity and require it to have a global O(2) symmetry with the original scalar field in the Brans-Dicke gravity. This gives us a new massless scalar field in the Einstein frame due to…

High Energy Physics - Phenomenology · Physics 2025-10-31 Muzi Hong , Kyohei Mukaida , Tsutomu T. Yanagida

A data-driven approach to elucidating the nature of the dark energy, in the form of a joint analysis of a full set of cosmological parameters, utilizing all available observational data is proposed. A parameterization of a generalized dark…

Astrophysics · Physics 2007-05-23 Greg Huey

Observational evidence for the existence of dark energy is strong. Here we suggest a model which is based on a modified gravitational theory in 5D and interpret the 5th dimension as a manifestation of dark energy in the 4D observable…

High Energy Physics - Theory · Physics 2008-01-22 H. Alavirad , N. Riazi

The generalized hybrid metric-Palatini theory of gravity admits a scalar-tensor representation in terms of two interacting scalar fields. We show that, upon an appropriate choice of the interaction potential, one of the scalar fields…

General Relativity and Quantum Cosmology · Physics 2020-06-08 Paulo M. Sá

In this work, we investigate the phenomenologically emergent dark energy (PEDE) model and its generalized form, namely the generalized emergent dark energy (GEDE) model, which introduces a free parameter \unboldmath {\( \Delta \)} that can…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-25 GuangZhen Wang , Xiaolei Li , Nan Liang
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