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Related papers: Relativistic interacting fluids in cosmology

200 papers

Perhaps the deepest mystery of our accelerating Universe in expansion is the existence of a tiny and rigid cosmological constant, $\Lambda$. Its size is many orders of magnitude below the expected one in the standard model of particle…

General Relativity and Quantum Cosmology · Physics 2015-04-03 Joan Sola , Adria Gomez-Valent

The paper explores a plane symmetric cosmological model within the framework of the Lyra manifold, incorporating interactions among various fields. These fields include a charged perfect fluid, a mass-less scalar field, and an…

General Relativity and Quantum Cosmology · Physics 2024-03-05 R. V. Mapari , D. D. Pawar , V. R. Patil , J. L. Pawde

Extensions of Einstein's General Relativity (GR) can formally be given a GR structure in which additional geometric degrees of freedom are mapped on an effective energy-momentum tensor. The corresponding effective cosmic medium can then be…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-11 Winfried Zimdahl , Hermano Velten , William C. Algoner

Introducing an effective refraction index of an isotropic cosmic medium, we investigate the cosmological fluid dynamics which is consistent with a conformal, timelike symmetry of a corresponding ``optical'' metric. We demonstrate that this…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Winfried Zimdahl , Alexander B. Balakin

We study cosmological dynamics of an extended gravitational theory that gravity is coupled non-minimally with derivatives of a dark energy component and there is also a phenomenological interaction between the dark energy and dark matter.…

General Relativity and Quantum Cosmology · Physics 2016-05-20 Kourosh Nozari , Noushin Behrouz

A macroscopic and kinetic relativistic description for a decoupled multi-fluid cosmology endowed with gravitationally induced particle production of all components is proposed. The temperature law for each decoupled particle species is also…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-12 S. R. G. Trevisani , J. A. S. Lima

We study the effective Lagrangian, at leading order in derivatives, that describes the propagation of density and metric fluctuations in a fluid composed by an arbitrary number of interacting components. Our results can be applied to any…

High Energy Physics - Theory · Physics 2014-06-05 Guillermo Ballesteros , Brando Bellazzini , Lorenzo Mercolli

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

The possibility that the vacuum energy density (VED) could be time dependent in the expanding Universe is intuitively more reasonable than just a rigid cosmological constant for the entire cosmic history. The framework of the running vacuum…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-18 Joan Solà Peracaula

We study three interacting dark energy models within the framework of four-dimensional General Relativity and a spatially flat Universe. In particular, we first consider two vacuum models where dark energy interacts with dark matter, while…

General Relativity and Quantum Cosmology · Physics 2020-04-22 Grigoris Panotopoulos , Angel Rincon , Nelson Videla , Giovanni Otalora

We derive and analyze a class of spherically symmetric cosmological models whose source is an interactive mixture of inhomogeneous cold dark matter (DM) and a generic homogeneous dark energy (DE) fluid. If the DE fluid corresponds to a…

Astrophysics · Physics 2009-11-10 Roberto A Sussman , Israel Quiros , Osmel Martin Gonzalez

We investigate the cosmological dynamics of interacting Logarithmic Entropy Corrected Holographic Dark Energy model with Cold Dark Matter. Fixed points are determined and their corresponding cosmological models are presented. Moreover, the…

General Relativity and Quantum Cosmology · Physics 2016-09-27 F. Darabi , F. Felegary , M. R. Setare

Geometric interactions in a new relativistic geometric unified theory include interactions other than gravitation and electromagnetism. In a low energy limit one of these interactions leads essentially to a Fermi type theory of weak…

General Physics · Physics 2007-05-23 Gustavo R. Gonzalez-Martin

Starting from an inhomogeneous space-time model of the universe we could recreate a scenario of recent time accelerating universe dominated by Dark Energy type of fluid. The background matter component of such a universe was considered to…

General Relativity and Quantum Cosmology · Physics 2023-02-06 Subhra Bhattacharya

We present new method for studying the equilibrium properties of interacting fluids in an arbitrary external filed. The method is valid in any dimension and it yields an exact results in one dimension. Using this approach, we derive a…

Soft Condensed Matter · Physics 2017-02-17 Benaoumeur Bakhti

We study a theory which generalizes the nonminimal coupling of matter to gravity by including derivative couplings. This leads to several interesting new dynamical phenomena in cosmology. In particular, the range of parameters in which…

General Relativity and Quantum Cosmology · Physics 2009-10-22 Luca Amendola

Considering an arbitrary, varying equation of the state parameter, the thermodynamic properties of the dark energy fluid in a semiclassical loop quantum cosmology scenario, which we consider the inverse volume modification, is studied. The…

General Relativity and Quantum Cosmology · Physics 2011-03-22 Kui Xiao , Jian-Yang Zhu

Motion equations describing streams of relativistic particles and their properties are explored in detail in the framework of Cosmological Perturbation Theory. Those equations, derived in any metric both in the linear and nonlinear regimes,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Hélène Dupuy , Francis Bernardeau

A new truncation scheme based on the cumulant expansion of the one-particle phase-space distribution function for dark matter particles is developed. Extending the method of moments in relativistic kinetic theory, we derive evolution…

High Energy Physics - Phenomenology · Physics 2020-09-23 Alaric Erschfeld , Stefan Floerchinger , Maximilian Rupprecht

We present hydrodynamic equations with relativistic pressure and velocity in the presence of weak gravity, in a cosmological context. Previously we consistently derived special relativistic hydrodynamic equations with weak gravity in…

General Relativity and Quantum Cosmology · Physics 2018-11-14 Hyerim Noh , Jai-chan Hwang , Chan-Gyung Park