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Related papers: Two Fluid Scenario in Bianchi Type-I Universe

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In this paper, we investigate Bianchi type$-V$ cosmological models with bulk viscous fluid and time varying cosmological $\Lambda$ and Newtonian $G$ parameters. The Einstein's field equations have been transformed into a coupling…

We investigate the cosmological applications of fluids having an equation of state which is the analog to the one related to the isotropic deformation of crystalline solids, that is containing logarithmic terms of the energy density,…

General Relativity and Quantum Cosmology · Physics 2018-11-14 S. D. Odintsov , V. K. Oikonomou , A. V. Timoshkin , Emmanuel N. Saridakis , R. Myrzakulov

A plane symmetric Bianchi-I model is explored in $f(R,T)$ gravity, where $R$ is the Ricci scalar and $T$ is the trace of energy-momentum tensor. The solutions are obtained with the consideration of a specific Hubble parameter which yields a…

General Relativity and Quantum Cosmology · Physics 2020-03-23 Vijay Singh , Aroonkumar Beesham

In this work, we will explore the effects of F(R) theories in the classical scheme using the anisotropic Bianchi Type I cosmological model with standard matter employing a barotropic fluid with equation of state $P=\gamma \rho$. In this…

General Relativity and Quantum Cosmology · Physics 2026-04-15 J. Socorro , Juan Luis Pérez , Luis Rey Díaz-Barrón , Abraham Espinoza García , Sinuhé Pérez Payán

We compare several well-known cosmological dark energy models using observational data coming both from type Ia supernovae and from Hubble parameter measurements. First we use supernovae data to determine the free parameters of each model…

General Relativity and Quantum Cosmology · Physics 2019-04-30 Grigoris Panotopoulos , Angel Rincon

Within the framework of the minimum quadratic Poincare gauge theory of gravity in the Riemann-Cartan spacetime the dynamics of homogeneous anisotropic Bianchi types I-IX spinning-fluid cosmological models is investigated. A basic equation…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Nguyen Hong Chuong , Nguyen Van Hoang

Bianchi cosmologies are ``natural'' anisotropic extensions of the Friedmann universes and they have long been used to investigate the cosmological implications of anisotropy. The latter introduces new ingredients to the standard scenarios,…

General Relativity and Quantum Cosmology · Physics 2024-09-13 Amalia Tzartinoglou , Christos G. Tsagas

The present study investigates the nature of the field potential via new technique known as reconstruction method for the scalar field potentials. The key point of this technique is the assumption that Hubble parameter is dependent on the…

General Relativity and Quantum Cosmology · Physics 2013-10-14 M. Sharif , Saira Waheed

LRS Bianchi type-I models have been studied in the cosmological theory based on Lyra's geometry. A new class of exact solutions has been obtained by considering a time dependent displacement field for variable deceleration parameter models…

General Relativity and Quantum Cosmology · Physics 2010-05-28 Anirudh Pradhan , D. S. Chauhan

The standard cosmological model is challenged by an ever-growing collection of observations, which invites (and stimulates) inquiry into possible additions and/or alterations. One such alteration comes from letting cosmic isotropy -- as…

General Relativity and Quantum Cosmology · Physics 2026-04-22 Robbert W. Scholtens , Marcello Seri , Holger Waalkens , Rien van de Weygaert

Currently, a large amount of data implies that the matter constituents of the cosmological dark sector might be collisional. An attractive feature of such a possibility is that, it can reconcile dark matter (DM) and dark energy (DE) in…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-25 K. Kleidis , N. K. Spyrou

While cold dark matter is widely supported by a range of cosmological observations, it encounters several difficulties at smaller scales. These issues have prompted the investigation of various alternative dark matter candidates, leaving…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-23 Jian-Qi Liu , Yan-Hong Yao , Yan Su , Jia-Wei Wu

The objective of this work enclosed with the study of spatially homogeneous anisotropic Bianchi type-I universe in $f(R,T)$ gravity (where $R$ is the Ricci scalar and $T$ is the trace of stress energy momentum tensor) in two different cases…

General Relativity and Quantum Cosmology · Physics 2017-03-20 P. K. Sahoo , Parbati Sahoo , Binaya K. Bishi

We consider the conformal Einstein equations for polytropic perfect fluid cosmologies which admit an isotropic singularity. For the polytropic index gamma strictly greater than 1 and less than or equal to 2 it is shown that the Cauchy…

General Relativity and Quantum Cosmology · Physics 2009-10-31 K. Anguige , K. P. Tod

The effective theory of the Anton-Schmidt cosmic fluid within the Debye approximation is investigated. In this picture, the universe is modeled out by means of a medium without cosmological constant. In particular, the Anton-Schmidt…

General Relativity and Quantum Cosmology · Physics 2019-02-06 Salvatore Capozziello , Rocco D'Agostino , Roberto Giambò , Orlando Luongo

The main purpose of this paper is to explore the solutions of Bianchi type $III$ cosmological model in Brans Dicke theory of gravity in the background of anisotropic dark energy. We use the assumption of constant deceleration parameter and…

General Relativity and Quantum Cosmology · Physics 2017-08-23 M. Farasat Shamir , Akhlaq Ahmad Bhatti

We analyse an inhomogeneous cosmological model featuring a spherically symmetric bubble solution induced by a unified single perfect fluid, comprising spatially dependent Dark Energy (with $w=-1$) and Dark Matter (with $w=0$) components. We…

General Relativity and Quantum Cosmology · Physics 2025-01-15 D. Comelli

A Bianchi type -I metric of Kasner form is considered, when the space is filled with a viscous fluid. Whereas an ideal (nonviscous) fluid permits the Kasner metric to be anisotropic provided that the fluid satisfies the Zel'dovich equation…

General Relativity and Quantum Cosmology · Physics 2009-01-14 I. Brevik , S. V. Pettersen

The objective of the present work is to study a cosmological model for a spatially flat Universe whose constituents are a dark energy field and a matter field which includes baryons and dark matter. The constituents are supposed to be in…

General Relativity and Quantum Cosmology · Physics 2013-09-13 Gilberto M. Kremer , Octavio A. S. Sobreiro

We propose a cosmological scenario in which, beyond matter and radiation, an additional barotropic fluid with positive equation of state $\omega_s$ contributes to the cosmic energy budget, in contrast to Early Dark Energy (EDE). We…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-21 Youri Carloni , Orlando Luongo
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