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A new model describing the dark sector of the universe is established. The model involves Bose-Einstein condensate (BEC) as dark energy (DE) and an excited state above it as dark matter (DM). The condensate is assumed to have a negative…

General Relativity and Quantum Cosmology · Physics 2011-05-24 V. A. Popov

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

In this work we investigate the background dynamics when dark energy is coupled to dark matter with a suitable interaction in the universe described by Loop quantum cosmology. Dark energy in the form of Generalised Cosmic Chaplygin gas is…

General Physics · Physics 2015-06-04 Ratul Chowdhury , Prabir Rudra

We investigate the dark energy phenomenology in an extended parameter space where we allow the curvature density of our universe as a free-to-vary parameter. The inclusion of the curvature density parameter is motivated from the recently…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-29 Mehdi Rezaei , Supriya Pan , Weiqiang Yang , David F. Mota

Motivated by the cosmological constant and the coincidence problems, we consider a cosmological model where the dark sectors are interacting together through a phenomenological decay law $\dot{\rho}_{\Lambda}=Q\rho_{\Lambda}^n$ in a FRW…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Vincent Poitras

Hybrid Chaplygin gas model is put forward, in which the gases play the role of dark energy. For this model the coincidence problem is greatly alleviated. The effective equation of state of the dark energy may cross the phantom divide…

Astrophysics · Physics 2015-05-13 Hongsheng Zhang , Zong-Hong Zhu , Lihua Yang

Massive particle and antiparticle pair production and oscillation on the horizon form a holographic and massive pair plasma state in the Friedman Universe. Via this state, the Einstein cosmology term (dark energy) interacts with matter and…

General Relativity and Quantum Cosmology · Physics 2024-05-21 She-Sheng Xue

In this work we have used the recent cosmic chronometers data along with the latest estimation of the local Hubble parameter value, $H_0$ at 2.4\% precision as well as the standard dark energy probes, such as the Supernovae Type Ia, baryon…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-02 Weiqiang Yang , Narayan Banerjee , Supriya Pan

A self-consistent model which can unify Starobinsky inflation and the $\Lambda$CDM model in the framework of Poincar\'e gauge cosmology (PGC) is studied in this work, without extra inflaton and ``dark energy''. We start from the general…

General Relativity and Quantum Cosmology · Physics 2019-10-07 Hongchao Zhang , Lixin Xu

Recently, a model of modified gravity plus single scalar field model was proposed, in which the scalar couples both to the standard Riemannian volume form given by the square root of the determinant of the Riemannian metric, as well as to…

General Relativity and Quantum Cosmology · Physics 2016-12-09 Denitsa Staicova , Michail Stoilov

We investigate constraints on some key cosmological parameters by confronting metastable dark energy models with different combinations of the most recent cosmological observations. Along with the standard $\Lambda$CDM model, two…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-14 Xiaolei Li , Arman Shafieloo , Varun Sahni , Alexei A. Starobinsky

We introduce a power-law parameterized quintessence model for the dark energy which accelerate universe at the low redshifts while behaves as an ordinary matter for the early universe. We construct a unique scalar potential for this…

Astrophysics · Physics 2008-11-26 Sohrab Rahvar , M. Sadegh Movahed

In this paper we study a model of interacting dark energy - dark matter where the ratio between these components is not constant, changing from early to late times in such a way that the model can solve or alleviate the cosmic coincidence…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-12 J. F. Jesus , A. A. Escobal , D. Benndorf , S. H. Pereira

In this paper, applying the Hartman-Grobman theorem we carry out a qualitative late-time analysis of some unified dark energy-matter Friedmann cosmological models, where the two interact through linear energy exchanges, and the dark energy…

General Relativity and Quantum Cosmology · Physics 2020-05-06 Muhsin Aljaf , Daniele Gregoris , Martiros Khurshudyan

We present a comprehensive study of the observational constraints on spatially flat cosmological models containing a mixture of matter and quintessence --- a time varying, spatially inhomogeneous component of the energy density of the…

Astrophysics · Physics 2009-09-15 Limin Wang , R. R. Caldwell , J. P. Ostriker , Paul J. Steinhardt

We propose a new pressure-parametrization model to explain the accelerated expansion of the late-time Universe by considering the dark contents (dark matter and dark energy) as a unified dark fluid. To realize this model more physically, we…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-30 Deng Wang , Yang-Jie Yan , Xin-He Meng

In this work we investigate the background dynamics when dark energy is coupled to dark matter with a suitable interaction in the universe described by brane cosmology. Here DGP and the RSII brane models have been considered separately.…

General Relativity and Quantum Cosmology · Physics 2012-03-12 Prabir Rudra , Ujjal Debnath , Ritabrata Biswas

In this work we investigate the background dynamics when dark energy is coupled to dark matter with a suitable interaction in the universe described by Einstein-Aether gravity. Dark energy in the form of Modified Chaplygin gas is…

General Physics · Physics 2014-08-21 Chayan Ranjit , Prabir Rudra , Sujata Kundu

We present an analysis of cosmological models with mixed dark matter (spectrum slope of density perturbations $n_S \in [0.6, 1.6]$, hot dark matter abundance $\Omega_\nu \in [0.0, 0.6]$) in spatially flat Universe, based on Press-Schechter…

Astrophysics · Physics 2011-04-15 N. A. Arkhipova , V. N. Lukash , E. V. Mikheeva

In this paper we study the cosmic acceleration for five dynamical dark energy models whose equation of state varies with redshift. The cosmological parameters of these models are constrained by performing a MCMC analysis using mainly gas…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-31 Juan Magana , V. Motta , Victor H. Cardenas , G. Foex
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