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We revise the cosmological interaction between dark energy and dark matter. More precisely, we focus on models that support compartmentalization or co-existence in the dark sector of the universe. Within the framework of a homogeneous and…

General Relativity and Quantum Cosmology · Physics 2024-11-25 Andronikos Paliathanasis , Kevin Duffy , Amlan Halder , Amare Abebe

We derive a model of dark energy which evolves with time via the scale factor. The equation of state $\omega=(1-2\alpha)/(1+2\alpha)$ is studied as a function of a parameter $\alpha$ introduced in this model. In addition to the recent…

General Relativity and Quantum Cosmology · Physics 2017-06-20 Hemza Azri , A. Bounames

Extending previous results [Phys. Rev. Lett. 97, 081301 (2006)], we explore the cosmological implications of a new quintessence scenario driven by a slow rolling homogeneous scalar field whose equation of state behaved as freezing over the…

Astrophysics · Physics 2010-01-15 J. S. Alcaniz , R. Silva , F. C. Carvalho , Zong-Hong Zhu

The Standard Model of cosmology, $\Lambda$CDM, while enormously successful, is currently unable to account for several cosmological anomalies the most prominent of which are in the measurements of the Hubble parameter and $S_8$.…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-14 Amin Aboubrahim , Pran Nath

Recent observations of Type Ia supernova at high redshifts establish that the dark energy component of the universe has (a probably constant) ratio between pressure and energy density $w=p/\rho=-1.02(^{+0.13}_{-0.19})$. The conventional…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Edgard Gunzig , Alberto Saa

In this work we analyze the full linear behaviour of the constrained interacting dark energy (CIDER) model, which is a conformally coupled quintessence model tailored to mimic a $\Lambda$CDM expansion. We compute the matter and temperature…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-18 Bruno J. Barros , Diogo Castelão , Vitor da Fonseca , Tiago Barreiro , Nelson J. Nunes , Ismael Tereno

Unless some unknown symmetry in Nature prevents or suppresses a non-minimal coupling in the dark sector, the dark energy field may interact with the pressureless component of dark matter. In this paper, we investigate some cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-28 F. E. M. Costa , E. M. Barboza , J. S. Alcaniz

Cosmological consequences of a string-motivated dark energy scenario featuring a scalar field coupled to the Gauss-Bonnet invariant are investigated. We study the evolution of the universe in such a model, identifying its key properties.…

Astrophysics · Physics 2008-11-26 Tomi Koivisto , David F. Mota

Imagine a scenario in which the dark energy forms via the condensation of dark matter at some low redshift. The Compton wavelength therefore changes from small to very large at the transition, unlike quintessence or metamorphosis. We study…

Astrophysics · Physics 2009-11-07 Bruce A. Bassett , Martin Kunz , David Parkinson , Carlo Ungarelli

Any non-gravitational coupling between dark matter and dark energy modifies the cosmological dynamics. Interactions in the dark sector are considered to be relevant to address the coincidence problem. Moreover, in various models the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 W. Zimdahl

It is extraordinary that a number of observations indicate that we live in a spatially flat, low matter density Universe, which is currently undergoing a period of accelerating expansion. The effort to explain this current state has focused…

Astrophysics · Physics 2010-02-18 R. R. Caldwell

A cosmological model is proposed for the current Universe consisted of non-interacting baryonic matter and interacting dark components. The dark energy and dark matter are coupled through their effective barotropic indexes, which are…

Astrophysics · Physics 2009-06-15 Luis P. Chimento , Monica Forte , Gilberto M. Kremer

Interacting dark energy-dark matter models have been widely analyzed in the literature in an attempt to find traces of new physics beyond the usual cosmological ($\Lambda$CDM) models. Such a coupling between both dark components is usually…

General Relativity and Quantum Cosmology · Physics 2022-08-17 Diego Álvarez-Ortega , Gonzalo J. Olmo , Diego Rubiera-García , Diego Sáez-Chillón Gómez

A simple speed-up cosmology model is proposed to account for the dark energy puzzle. We condense contributions from dark energy and curvature term into one effective parameter in order to reduce parameter degeneracies and to find any…

Astrophysics · Physics 2007-10-10 Xin-He Meng , Meng Su , Zheng Wang

We consider new models of dark energy with finite time future singularities, by introducing the pressure density as a function of the scale factor. This approach gives acceptable phenomenological models of dark energy, practically…

General Relativity and Quantum Cosmology · Physics 2019-07-17 L. N. Granda

A well-known problem of the $\Lambda$CDM model is the tension between the relatively high level of clustering, as quantified by the parameter $\sigma_8$, found in cosmic microwave background experiments and the smaller one obtained from…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-04 Bruno J. Barros , Luca Amendola , Tiago Barreiro , Nelson J. Nunes

This paper deals with the cancellation mechanism, which identifies the energy density of space-time expansion in an empty universe with the zero-point energy density and avoids the scale discrepancy with the observed energy density…

General Physics · Physics 2018-06-12 Christian Henke

The dynamical properties of a model of dark energy in which two scalar fields are coupled by a non-canonical kinetic term are studied. We show that overall the addition of the coupling has only minor effects on the dynamics of the two-field…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Carsten van de Bruck , Joel M. Weller

We consider a model where both dark energy and dark matter originate from the coupling of a scalar field with a non-conventional kinetic term to, both, a metric measure and a non-metric measure. An interacting dark energy/dark matter…

General Relativity and Quantum Cosmology · Physics 2015-06-11 Stefano Ansoldi , Eduardo I. Guendelman

We extend the cosmological couplings proposed in Sun et al. and Wei, where they suggested interactions with change of signs along the cosmological evolution. Our extension liberates the changes of sign of the interaction from the…

General Relativity and Quantum Cosmology · Physics 2014-09-25 Mónica Forte