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A so-called "agegraphic dark energy" was recently proposed to explain the dark energy-dominated universe. In this Letter, we generalize the agegraphic dark energy models to the universe with spatial curvature in the presence of interaction…

High Energy Physics - Theory · Physics 2009-10-16 Ahmad Sheykhi

In this manuscript, we present a novel dark energy model to study the nature of dark energy. Non-extensive Kaniadakis entropy and, timescale as infrared cutoff are the major tools of the current study. Age of the Universe will serve the…

General Physics · Physics 2022-05-09 Suresh Kumar P , Bramha Dutta Pandey , Pankaj , Umesh Kumar Sharma

The new agegraphic Dark Energy (NADE) model (based on generalized uncertainty principle) interacting with Dark Matter (DM) is considered in this study via power-law form of the scale factor $a(t)$. The equation of state (EoS) parameter…

General Physics · Physics 2013-11-14 Antonio Pasqua , Surajit Chattopadhyay , Iuliia Khomenko

Combining the general relativity and the uncertainty relation in quantum mechanics, the energy density of quantum fluctuations of space-time can be viewed as dark energy. The so-called agegraphic dark energy model is just based on this…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-18 Jinglei Cui , Li Zhang , Jingfei Zhang , Xin Zhang

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 difference between holographic dark energy, Chaplygin gas, and tachyon model with constant potential. For this purpose, we examine their squared speeds of sound which are evaluated to zeroth order in perturbation theory…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Yun Soo Myung

In this manuscript, we examine the cosmological significance of the new agegraphic dark energy model by investigating different cosmological parameters such as the equation of state parameter, $\omega_{D}-\omega^{\prime}_{D}$ and the $r-s$…

General Relativity and Quantum Cosmology · Physics 2025-01-03 Madiha Ajmal , M. Sharif

Stability analysis of agegraphic dark energy in Brans-Dicke theory is presented in this paper. We constrain the model parameters with the observational data and thus the results become broadly consistent with those expected from experiment.…

General Physics · Physics 2015-06-03 H. Farajollahi , J. Sadeghi , M. Pourali , A. Salehi

We investigate the instability of the ghost dark energy model against perturbations in different cases. To this goal we use the squared sound speed $v_s^2$ whose sign determines the stability of the model. When $v_s^2<0$ the model is…

High Energy Physics - Theory · Physics 2015-03-19 Esmaeil Ebrahimi , Ahmad Sheykhi

We investigate the origin of holographic dark energy models which were recently proposed to explain the dark energy-dominated universe. For this purpose, we introduce the spacetime foam uncertainty of $\delta l \ge l_{\rm…

General Relativity and Quantum Cosmology · Physics 2009-02-02 Yun Soo Myung , Min-Gyun Seo

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

An impressive amount of different astrophysical data converges towards the picture of a spatially flat universe undergoing a today phase of accelerated expansion. The nature of the dark energy dominating the energy content of the universe…

Astrophysics · Physics 2009-11-10 S. Capozziello , V. F. Cardone , M. Funaro , S. Andreon

In this note, we propose a new model of agegraphic dark energy based on the K\'{a}rolyh\'{a}zy relation, where the time scale is chosen to be the conformal time $\eta$ of the Friedmann-Robertson-Walker (FRW) universe. We find that in the…

Astrophysics · Physics 2008-11-26 Hao Wei , Rong-Gen Cai

In this paper, we investigate the agegraphic dark energy (ADE) model by including the sign-changeable interaction between ADE and dark matter in non-flat universe. It is shown that the interaction induces an energy flow of which the…

Cosmology and Nongalactic Astrophysics · Physics 2016-05-04 Y. D. Xu

In this paper, we explore various cosmological parameters and cosmological planes ($\omega_D-{\omega_D}^{\prime}$, statefinder) for new Tsallis agegraphic dark energy in the framework of Chern-Simons modified gravity. We consider this…

General Physics · Physics 2020-01-23 M. Abdollahi Zadeh

In this work, we propose a new dark energy model by applying the Barrow entropy and the holographic principle, with a time scale as IR cut off. Analysing the conformal time as well as universe's age as infrared cut-offs, we explore the…

General Relativity and Quantum Cosmology · Physics 2020-12-29 Umesh Kumar Sharma , Gunjan Varshney , Vipin Chandra Dubey

Using the nonextensive Tsallis entropy and the holographic hypothesis, we propose a new dark energy (DE) model with time scale as infrared (IR) cutoff. Considering the age of the Universe as well as the conformal time as IR cutoffs, we…

General Physics · Physics 2019-04-01 M. Abdollahi Zadeh , A. Sheykhi , H. Moradpour

By studying the present cosmological data, particularly on CMB, SNeIA and LSS, we find that the future fate of the universe, for simple linear models of the dark energy equation-of-state, can vary between the extremes of (I) a divergence of…

Astrophysics · Physics 2009-11-10 Paul H. Frampton

The nature of dark energy can be probed not only through its equation of state, but also through its microphysics, characterized by the sound speed of perturbations to the dark energy density and pressure. As the sound speed drops below the…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-25 Roland de Putter , Dragan Huterer , Eric V. Linder

Recent cosmological observations strongly suggest that the universe is dominated by an unknown form of energy with negative pressure. Why is this dark energy density of order the critical density today? We propose that the dark energy has…

Astrophysics · Physics 2009-12-15 Scott Dodelson , Manoj Kaplinghat , Ewan Stewart
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