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Related papers: A novel early Dark Energy model

200 papers

Early dark energy (EDE), introduced at the epoch of matter-radiation equality to alleviate the Hubble tension, has posed a new coincidence problem: why EDE appears at matter-radiation equality when their physics are completely unrelated? To…

General Relativity and Quantum Cosmology · Physics 2024-02-07 Changcheng Jing , Shuxun Tian , Zong-Hong Zhu

We introduce a modified form of the Phenomenologically Emergent Dark Energy (PEDE) model by showing a very elegant approach. The model is named as Modified Emergent Dark Energy (MEDE) to distinguish from PEDE model and it includes…

General Relativity and Quantum Cosmology · Physics 2020-08-24 H. B. Benaoum , Weiqiang Yang , Supriya Pan , Eleonora Di Valentino

Many quintessence models possess scaling or attractor solutions where the fraction of dark energy follows the dominant component in previous epochs of the expansion, or phase transitions may happen close to matter-radiation equality time. A…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-03 Adrià Gómez-Valent , Ziyang Zheng , Luca Amendola , Valeria Pettorino , Christof Wetterich

We present a complete analysis of the observational constraints and cosmological implications of our Bound Dark Energy (BDE) model aimed to explain the late-time cosmic acceleration of the universe. BDE is derived from particle physics and…

Cosmology and Nongalactic Astrophysics · Physics 2019-05-15 Erick Almaraz , Axel de la Macorra

We reconstruct evolution of the dark energy (DE) density using a nonparametric Bayesian approach from a combination of latest observational data. We caution against parameterizing DE in terms of its equation of state as it can be singular…

Cosmology and Nongalactic Astrophysics · Physics 2018-12-12 Yuting Wang , Levon Pogosian , Gong-Bo Zhao , Alex Zucca

Early dark energy models, for which the contribution to the dark energy density at high redshifts is not negligible, influence the growth of cosmic structures and could leave observable signatures that are different from the standard…

Cosmology and Nongalactic Astrophysics · Physics 2009-04-01 Jun-Qing Xia , Matteo Viel

To reconstruct dark energy models the redshift $z_{eq}$, marking the end of radiation era and the beginning of matter-dominated era, can play a role as important as $z_{t}$, the redshift at which deceleration parameter experiences a…

General Relativity and Quantum Cosmology · Physics 2009-11-18 A. Sil , S. Som

In this paper we present an alternative explanation to the acceleration of the universe and the dark energy problems in terms of the Friedmann Thermodynamics. This model has the capability of making definite predictions in-line with the…

Astrophysics · Physics 2007-05-23 Selcuk Bayin

We explore a model of interacting Early Dark Energy (EDE) in which a minimally coupled scalar field, representing the EDE, interacts with the radiation sector through an exponential coupling function in the radiation-dominated era. This…

General Relativity and Quantum Cosmology · Physics 2025-08-15 Yousef Bisabr

There are many kinds of models which describe the dynamics of dark energy (DE). Among all we adopt an equation of state (EoS) which varies as a function of time. We adopt Markov Chain Monte Carlo method to constrain the five parameters of…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-15 R. Ichimasa , E. P. B. A. Thushari , M. Hashimoto

Early dark energy (EDE) is an extension to the $\Lambda$CDM model, proposed to reduce the tension between the measurements of the Hubble constant $H_0$ from the cosmic microwave background (CMB) and from the local cosmic distance ladder.…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-12 João Rebouças , Jonathan Gordon , Diogo H. F. de Souza , Kunhao Zhong , Vivian Miranda , Rogerio Rosenfeld , Tim Eifler , Elisabeth Krause

A general equation of state is considered for analysing the possible behaviors for (Early) dark energy that alleviates the Hubble parameter tension problem. By departing from the possible evolution for the (Early) dark energy density and…

General Relativity and Quantum Cosmology · Physics 2021-05-25 Shin'ichi Nojiri , Sergei D. Odintsov , Diego Saez-Chillon Gomez , German S. Sharov

A phenomenological approach is proposed to the problem of universe accelerated expansion and of the dark energy nature. A general class of models is introduced whose energy density depends on the redshift $z$ in such a way that a smooth…

Astrophysics · Physics 2009-11-10 V. F. Cardone , A. Troisi , S. Capozziello

Determination of the expansion and acceleration history of the universe is one of the fundamental goals of cosmology. Detailed measurements of these rates as a function of redshift can provide new physical insights into the nature and…

Astrophysics · Physics 2009-11-07 Ruth A. Daly , S. G. Djorgovski

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

In order to explain the current acceleration of the Universe, the fine tuning problem of the cosmological constant $\Lambda$ and the cosmic coincidence problem, different alternative models have been proposed in the literature. We use the…

Cosmology and Nongalactic Astrophysics · Physics 2019-05-13 Alexander Bonilla Rivera , Jorge García Farieta

One of the most important and surprising discoveries in cosmology in recent years is the realization that our Universe is dominated by a mysterious dark energy, which leads to an accelerating expansion of space-time. A simple generalization…

Astrophysics · Physics 2007-05-23 Baojiu Li , Ming-Chung Chu , Kai-Chung Cheung , Alfred Tang

We present the cosmic expansion scenario in the framework of $f(T)$ gravity by employing a dark energy equation of state (EoS) parameter. Specifically, we proceed with the power-law form of the function $f(T) = \alpha$$(-T)^{n}$, in…

General Relativity and Quantum Cosmology · Physics 2026-04-21 Khomesh R. Patle , G. P. Singh

Dark energy (DE) plays an important role in the expansion history of our universe. But we only got limited knowledge about its nature and properties after decades of study.In most numerical researches, DE is usually considered as a…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-02 Ke Wang , Lu Chen

One of the main challenges of modern cosmology is to investigate the nature of dark energy in our Universe. The properties of such a component are normally summarised as a perfect fluid with a (potentially) time-dependent equation-of-state…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-19 J. Alberto Vazquez , M. Bridges , M. P. Hobson , A. N. Lasenby