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Related papers: Thermodynamic Constraints on the Dark Sector

200 papers

We study the polytropic gas scenario as the unification of dark matter and dark energy. We fit the model parameters by using the latest observational data including type Ia supernovae, baryon acoustic oscillation, cosmic microwave…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-01 K. Karami , Z. Safari , S. Asadzadeh

In this paper the coupling between dark energy and the other components of the cosmological fluid has been studied. Firstly, it will be shown that the application of general cosmological equations, deduced by the authors in a previous work,…

Cosmology and Nongalactic Astrophysics · Physics 2010-06-02 Alberto C. Balfagon , Raul Ramirez-Satorras , Angel R. Martinez

Despite our present-day inability to predict the topology of the universe it is expected that we should be able to detect it in the near future. A nontrivial detectable topology of the space section of the universe can be probed for all…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-04 M. J. Reboucas , A. F. F. Teixeira

In this work, we examine the main cosmological effects derived from a time-varying coupling ($\bar{Q}$) between a dark matter (DM) fluid and a dark energy (DE) fluid with time-varying DE equation state (EoS) parameter ($\omega_{DE}$), in…

General Relativity and Quantum Cosmology · Physics 2017-12-22 Freddy Cueva Solano

Scalar cosmological perturbations are investigated in the framework of a model with interacting dark energy and dark matter. In addition to these constituents, the inhomogeneous Universe is supposed to be filled with the standard…

General Relativity and Quantum Cosmology · Physics 2015-07-24 Maxim Eingorn , Claus Kiefer

Scalar fields aptly describe equation of state of dark energy. The scalar field models were initially proposed to circumvent the fine tuning problem of cosmological constant. However, the model parameters also need a fine tuning of their…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-19 Archana Sangwan , Ashutosh Tripathi , H. K. Jassal

In the context of thermodynamics we discuss the way inevitable emerge an interaction between dark components, and in this way, provide a mechanism to understand the limits of the LCDM model and the class of interaction models between dark…

Cosmology and Nongalactic Astrophysics · Physics 2019-05-22 Víctor H. Cárdenas , Daniela Grandón , Samuel Lepe

We compare supernovae and Baryon Acoustic Oscillations data to the predictions of a cosmological model of interacting dark matter and dark energy. This theoretical model can be derived from the effective field theory of Einstein-Cartan…

Cosmology and Nongalactic Astrophysics · Physics 2019-05-01 Damien Bégué , Clément Stahl , She-Sheng Xue

There is no unique way to describe the dark energy-dark matter interaction, as we have little information about the nature and dynamics of the dark sector. Hence, in many of the phenomenological dark matter fluid interaction models in the…

General Relativity and Quantum Cosmology · Physics 2021-01-13 Joseph P Johnson , S. Shankaranarayanan

A non-trivial spatial topology of the Universe is a potentially observable attribute, which can be probed through the circles-in-the-sky for all locally homogeneous and isotropic universes with no assumptions on the cosmological parameters.…

Cosmology and Nongalactic Astrophysics · Physics 2009-04-21 M. J. Reboucas

In this paper, after reconstructing the redshift evolution of the Hubble function by adopting Gaussian process techniques, we estimate the best-fit parameters for some flat Friedmann cosmological models based on a Modified Chaplygin Gas…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-28 Muhsin Aljaf , Daniele Gregoris , Martiros Khurshudyan

Alternative dark energy models were proposed to address the limitation of the standard concordance model. Though different phenomenological considerations of such models are widely studied, scenarios where they interact with each other…

General Relativity and Quantum Cosmology · Physics 2024-10-18 Pradosh Keshav MV , Kenath Arun

In this work we discuss a general approach for the dark energy thermodynamics considering a varying equation of state (EoS) parameter of the type $\omega(a)=\omega_0+F(a)$ and taking into account the role of a non-zero chemical potential…

Cosmology and Nongalactic Astrophysics · Physics 2013-12-12 H. H. B. Silva , R. Silva , R. S. Gonçalves , Zong-Hong Zhu , J. S. Alcaniz

Unified dark matter models are appealing in that they describe the dark sector in terms of a single component. They however face problems when attempting to account for structure formation: in the linear regime, density fluctuations can…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-16 Amr El-Zant

We present a unified description of the dark matter and the dark energy sectors, in the framework of shift-symmetric generalized Galileon theories. Considering a particular combination of terms in the Horndeski Lagrangian in which we have…

General Relativity and Quantum Cosmology · Physics 2018-02-07 George Koutsoumbas , Konstantinos Ntrekis , Eleftherios Papantonopoulos , Emmanuel N. Saridakis

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

We investigate the possibility of using cosmological observations to probe and constrain an imperfect dark energy fluid. We consider a general parameterization of the dark energy component accounting for an equation of state, speed of sound…

Astrophysics · Physics 2008-12-18 D. F. Mota , J. R. Kristiansen , T. Koivisto , N. E. Groeneboom

The equation of state characterizing the dark energy component is constrained by combining Chandra observations of the X-ray luminosity of galaxy clusters with independent measurements of the baryonic matter density and the latest…

Astrophysics · Physics 2008-11-26 J. A. S. Lima , J. V. Cunha , J. S. Alcaniz

This is one chapter of the collection of problems in cosmology, in which we assemble the problems that concern one of the most distinctive features of modern cosmology---the interaction in the Dark Sector. The evolution of any broadly…

Physics Education · Physics 2013-12-24 Yu. L. Bolotin , V. A. Cherkaskiy , O. A. Lemets , I. V. Tanatarov , D. A. Yerokhin

Most parameterizations of the dark energy equation of state do not reflect realistic underlying physical models. Here, we develop a relatively simple description of dark energy based on the dynamics of a scalar field which is exact in the…

Astrophysics · Physics 2008-11-26 Robert Crittenden , Elisabetta Majerotto , Federico Piazza