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Related papers: Variable sound speed in interacting dark energy mo…

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We investigate a dark energy scenario in which a canonical scalar field $\phi$ is coupled to the four velocity $u_{c}^{\mu}$ of cold dark matter (CDM) through a derivative interaction $u_{c}^{\mu} \partial_{\mu} \phi$. The coupling is…

General Relativity and Quantum Cosmology · Physics 2020-04-13 Ryotaro Kase , Shinji Tsujikawa

We examine the effects of possible phenomenological interactions between dark energy and dark matter on cosmological parameters and their efficiency in solving the coincidence problem. We work with two simple parameterizations of the…

Astrophysics · Physics 2009-06-23 Jian-Hua He , Bin Wang

The formalism of dark energy based on modeling speed of sound as a function of equation of state parameter is elaborated. A specific model which allows detailed study of cosmological constant boundary crossing is introduced and analytical…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-20 Dalibor Perkovic , Hrvoje Stefancic

In this paper, we test the dark matter-dark energy interacting cosmological model with a dynamic equation of state $w_{DE}(z)=w_{0}+w_{1}z/(1+z)$, using type Ia supernovae (SNe Ia), Hubble parameter data, baryonic acoustic oscillation (BAO)…

Cosmology and Nongalactic Astrophysics · Physics 2015-04-16 J. S. Wang , F. Y. Wang

Astronomical observations suggest that the current standard $\Lambda$-Cold Dark Matter model in modern cosmology has some discrepancies when fitting the data during the whole expansion history of the universe. To solve the Hubble constant…

General Relativity and Quantum Cosmology · Physics 2025-07-15 Wenzhong Liu , Yabo Wu , Supriya Pan , Weiqiang Yang

We study a coupled dark energy scenario in which a massive vector field $A_{\mu}$ with broken $U(1)$ gauge symmetry interacts with the four-velocity $u_c^{\mu}$ of cold dark matter (CDM) through the scalar product $Z=-u_c^{\mu} A_{\mu}$.…

General Relativity and Quantum Cosmology · Physics 2020-09-29 Antonio De Felice , Shintaro Nakamura , Shinji Tsujikawa

Models with dark energy decaying into dark matter have been proposed to solve the coincidence problem in cosmology. We study the effect of such coupling in the matter power spectrum. Due to the interaction, the growth of matter density…

Astrophysics · Physics 2008-11-26 G. Olivares , F. Atrio-Barandela , D. Pavon

A cosmological model with an energy transfer between dark matter (DM) and dark energy (DE) can give rise to comparable energy densities at the present epoch. The present work deals with the perturbation analysis, parameter estimation and…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-02 Srijita Sinha

We discuss the thermodynamic and dynamical properties of a variable dark energy model with density scaling as $\rho_x \propto (1+z)^{m}$, z being the redshift. These models lead to the creation/disruption of matter and radiation, which…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Philippe Jetzer , Crescenzo Tortora

In this review we consider in detail different theoretical topics associated with interaction in the dark sector. We study linear and nonlinear interactions which depend on the dark matter and dark energy densities. We consider a number of…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-25 Yu. L. Bolotin , A. Kostenko , O. A. Lemets , D. A. Yerokhin

We determine the range of parameter space of an interacting quintessence (IQ) model that best fits the luminosity distance of type Ia supernovae data and the recent WMAP measurements of Cosmic Microwave Background temperature anisotropies.…

Astrophysics · Physics 2009-11-13 German Olivares , Fernando Atrio-Barandela , Diego Pavon

In the present paper, we study the capability of interacting dark energy model with pure momentum transfer in the dark sector to reconcile tensions between low redshift observations and cosmic microwave background (CMB) results. This class…

Cosmology and Nongalactic Astrophysics · Physics 2020-02-11 Mahnaz Asghari , Shahram Khosravi , Amir Mollazadeh

Dark energy models with non-canonical kinetic energy terms, k-essence, can have dynamical and sound speed properties distinct from canonical scalar fields, quintessence. Concentrating on purely kinetic term Lagrangians, which can be…

Astrophysics · Physics 2008-11-26 Roland de Putter , Eric V. Linder

The coupling between the dark components provides a new approach to mitigate the coincidence problem of cosmological standard model. In this paper, dark energy is treated as a fluid with a constant equation of state, whose coupling with…

Cosmology and Nongalactic Astrophysics · Physics 2014-08-18 Weiqiang Yang , Lixin Xu

The dark sector of the Universe need not be completely separable into distinct dark matter and dark energy components. We consider a model of early dark energy in which the dark energy mimics a dark matter component in both evolution and…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-05 Jannis Bielefeld , Robert R. Caldwell , Eric V. Linder

We perform a full dynamical analysis by considering the interactions between dark energy and radiation, and dark energy and dark matter. We find that the interaction helps alleviate the coincidence problem for the quintessence model.

Cosmology and Nongalactic Astrophysics · Physics 2011-04-12 Yi Zhang , Hui Li , Yungui Gong , Zong-Hong Zhu

We consider the impact of dynamical dark energy (DDE) in the possible solution of the existing tensions in the $\Lambda$CDM. We test both interacting and non-interacting DE models with dark matter (DM). Among the former, the running vacuum…

Cosmology and Nongalactic Astrophysics · Physics 2019-04-26 Joan Sola , A. Gomez-Valent , J. de Cruz Perez

We analyse three cosmological scenarios with interaction in the dark sector, which are particular cases of a general expression for the energy flux from vacuum to matter. In the first case the interaction leads to a transition from an…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-31 L. P. Chimento , S. Carneiro

We consider the interaction between dark matter and dark energy in the framework of holographic dark energy, and propose a natural and physically plausible form of interaction, in which the interacting term is proportional to the product of…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-27 Yin-zhe Ma , Yan Gong , Xuelei Chen

Non-gravitational interaction between two barotropic dark fluids, namely the pressureless dust and the dark energy in a spatially flat Friedmann-Lema\^{i}tre-Robertson-Walker model has been discussed. It is shown that for the interactions…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-30 Supriya Pan , Ankan Mukherjee , Narayan Banerjee