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Related papers: Modeling dark energy with a top-down approach

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We present a brief review of various approaches to late time acceleration of universe. The cosmological relevance of scaling solutions is emphasized in case of scalar field models of dark energy. The underlying features of a variety of…

High Energy Physics - Theory · Physics 2009-01-21 M. Sami

We have reexamined the holographic dark energy model by considering the spatial curvature. We have refined the model parameter and observed that the holographic dark energy model does not behave as phantom model. Comparing the holographic…

High Energy Physics - Theory · Physics 2009-11-10 Yungui Gong , Bin Wang , Yuan-Zhong Zhang

Dark energy models and modified gravity theories have been actively studied and the behaviors in the solar system have been also carefully investigated in a part of the models. However, the isotropic solutions of the field equations in the…

General Relativity and Quantum Cosmology · Physics 2018-01-24 Jiro Matsumoto

We consider a generic cosmological model which allows for non-gravitational direct couplings between dark matter and dark energy. The distinguishing cosmological features of these couplings can be probed by current cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-17 Carsten van de Bruck , Jurgen Mifsud

We investigate the possibility of a dark energy component that is scaling with epochs. A phenomenological model is introduced whose energy density depends on the redshift in such a way that a smooth transition among the three dominant…

Astrophysics · Physics 2009-11-10 Salvatore Capozziello , Alessandro Melchiorri , Alice Schirone

A cosmological model of dark energy interacting with dark matter and another general component of the universe is investigated. We found general constraints on these models imposing an accelerated expansion. The same is also studied in the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Norman Cruz , Samuel Lepe , Francisco Pena

Holographic dark energy models have proven to be a very interesting way to study various aspects of late-time acceleration of the universe. In this work we extensively study HDE models with the Granda-Oliveros cutoff with an ansatz based…

General Relativity and Quantum Cosmology · Physics 2024-05-28 Oem Trivedi , Maxim Khlopov

Dark energy and dark matter are the dominant sources in the evolution of the late universe. They are currently only indirectly detected via their gravitational effects, and there could be a coupling between them without violating…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Christian G. Boehmer , Gabriela Caldera-Cabral , Ruth Lazkoz , Roy Maartens

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

In this paper we study cosmological application of holographic dark energy density in the modified gravity framework. We employ the holographic model of dark energy to obtain the equation of state for the holographic energy density in…

High Energy Physics - Theory · Physics 2010-11-11 M. R. Setare

A coupled dark energy model is considered, in which dark energy is represented by a generalized three-form field and dark matter by dust. By assuming the functions $N$ and $I$ in the model's Lagrangian as two power-law functions of the…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-13 Yan-Hong Yao , Xin-He Meng

We review the notion of holographic dark energy and assess its significance in the light of the well documented cosmic acceleration at the present time. We next propose a model of holographic dark energy in which the infrared cutoff is set…

High Energy Physics - Theory · Physics 2009-11-11 Diego Pavon , Winfried Zimdahl

We apply the gravity-thermodynamics approach in the case of Einstein-Gauss-Bonnet theory, and its corresponding Wald-Gauss-Bonnet entropy, which due to the Chern-Gauss-Bonnet theorem it is related to the Euler characteristic of the Universe…

General Relativity and Quantum Cosmology · Physics 2025-05-14 Stylianos A. Tsilioukas , Nicholas Petropoulos , Emmanuel N. Saridakis

Observing dark energy dynamics is the most important aspect of the dark energy research. In this paper we perform an analysis of the constraints on the property of dark energy from the current astronomical observations. We pay particular…

Astrophysics · Physics 2009-11-13 Jun-Qing Xia , Gong-Bo Zhao , Bo Feng , Hong Li , Xinmin Zhang

We address the fine-tuning problem of dark energy cosmologies which arises when the dark energy density needs to initially lie in a narrow range in order for its present value to be consistent with observations. As recently noticed, this…

Astrophysics · Physics 2009-11-10 Sabino Matarrese , Carlo Baccigalupi , Francesca Perrotta

In this mini-review we discuss first why we should investigate cosmological models beyond LCDM. We then show how to describe dark energy or modified gravity models in a fluid language with the help of one background and two perturbation…

Cosmology and Nongalactic Astrophysics · Physics 2012-09-24 Martin Kunz

In this paper the coupling between dark energy and the other components of the cosmological fluid has been studied. Firstly, it will be shown that the application of general cosmological equations, deduced by the authors in a previous work,…

Cosmology and Nongalactic Astrophysics · Physics 2010-06-02 Alberto C. Balfagon , Raul Ramirez-Satorras , Angel R. Martinez

The coupled dark energy model provides a possible approach to mitigate the coincidence problem of cosmological standard model. Here, the coupling term is assumed as $\bar{Q}=3H\xi_x\bar{\rho}_x$, which is related to the interaction rate and…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-11 Weiqiang Yang , Hang Li , Yabo Wu , Jianbo Lu

We address some recent erroneous claim that $H_0$ observations are difficult to accommodate with LTB cosmological models, showing how to construct solutions in agreement with an arbitrary value of $H_0$ by re-writing the exact solution in…

Cosmology and Nongalactic Astrophysics · Physics 2012-12-11 Antonio Enea Romano

In this study, cosmological models are considered, where dark matter and dark energy are coupled and may exchange energy through non-gravitational interactions with one other. These interacting dark energy (IDE) models have previously been…

General Relativity and Quantum Cosmology · Physics 2024-01-23 Marcel A. van der Westhuizen , Amare Abebe
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