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Related papers: Matter and dynamics in closed cosmologies

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In this paper cosmological dynamics in Einstein-Gauss-Bonnet gravity with a perfect fluid source in arbitrary dimension is studied. A systematic analysis is performed for the case that the theory does not admit maximally symmetric…

General Relativity and Quantum Cosmology · Physics 2018-03-15 Fabrizio Canfora , Alex Giacomini , Sergey A. Pavluchenko , Alexey Toporensky

The dynamics of the Einstein-Vlasov equations for a class of cosmological models with four Killing vectors is discussed in the case of massive particles. It is shown that in all models analysed the solutions with massive particles are…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Alan D. Rendall , Claes Uggla

We investigate the cosmic dynamics of Rastall gravity in non-flat Friedmann-Robertson-Walker (FRW) space-time with barotropic fluid. In this context, we are concerned about the class of model satisfying the affine equation of state. We…

General Relativity and Quantum Cosmology · Physics 2022-07-27 Ashutosh Singh , Gyan Prakash Singh , Anirudh Pradhan

In general relativity, for fluids with a linear equation of state (EoS) or scalar fields, the high isotropy of the universe requires special initial conditions, and singularities are anisotropic in general. In the brane world scenario…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Kishore N. Ananda , Marco Bruni

Via a straightforward integration of the Einstein equations with cosmological constant, all static circularly symmetric perfect fluid 2+1 solutions are derived. The structural functions of the metric depend on the energy density, which…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Alberto A. Garcia , Cuauhtemoc Campuzano

In this paper we explore how far the post-Newtonian theory goes in overcoming the difficulties associated with anisotropic homogeneous cosmologies in the Newtonian approximation. It will be shown that, unlike in the Newtonian case, the…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Tamath Rainsford

A recent article uncovered a surprising dynamical mechanism at work within the (vacuum) Einstein `flow' that strongly suggests that many closed 3-manifolds that do not admit a locally homogeneous and isotropic metric \textit{at all} will…

General Relativity and Quantum Cosmology · Physics 2019-03-04 Vincent Moncrief , Puskar Mondal

The asymptotic properties of the Bianchi type II cosmological model in the Brane-world scenario are investigated. The matter content is assumed to be a combination of a perfect fluid and a minimimally coupled scalar field that is restricted…

General Relativity and Quantum Cosmology · Physics 2009-11-07 R. J. van den Hoogen , J. Ibanez

This article is a guide to theorems on existence and global dynamics of solutions of the Einstein equations. It draws attention to open questions in the field. The local in time Cauchy problem, which is relatively well understood, is…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Alan D. Rendall

We investigate some new similarity inhomogeneous solutions of anisotropic dark energy and perfect fluid in Bianchi type-I space-time. Three different equation of state parameters along the spatial directions are introduced to quantify the…

General Relativity and Quantum Cosmology · Physics 2018-04-12 Ahmad T Ali , Anil Kumar Yadav , Abdulah K Alzahrani

Bianchi type I massive string cosmological model with magnetic field of barotropic perfect fluid distribution through the techniques used by Latelier and Stachel, is investigated. To get the deterministic model of the universe, it is…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Raj Bali , Umesh Kumar Pareek , Anirudh Pradhan

We investigated a flat multidimensional cosmological model in Gauss-Bonnet gravity in presence of a matter in form of perfect fluid. We found analytically new stationary regimes (these results are valid for arbitrary number of spatial…

General Relativity and Quantum Cosmology · Physics 2015-03-13 I. V. Kirnos , S. A. Pavluchenko , A. V. Toporensky

This paper deals with the evolution of the Einstein gravitational fields which are coupled to a perfect fluid. We consider the Einstein--Euler system in asymptotically flat spacestimes and therefore use the condition that the energy density…

Analysis of PDEs · Mathematics 2013-05-10 Uwe Brauer , Lavi Karp

A free massless scalar field is coupled to homogeneous and isotropic loop quantum cosmology. The coupled model is investigated in the vicinity of the classical singularity, where discreteness is essential and where the quantum model is…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Martin Bojowald , Franz Hinterleitner

Smooth Cauchy data for the Einstein-Lambda-vacuum field equations with positive cosmological constant Lambda that are sufficiently close to de Sitter data develop into a solution that admits a smooth conformal boundary Scri+ in its future.…

General Relativity and Quantum Cosmology · Physics 2023-10-13 Helmut Friedrich

The general solution of the field equations in LRS Bianchi-I space-time with perfect fluid equation-of-state (EoS) is presented. The models filled with dust, vacuum energy, Zel'dovich matter and disordered radiation are studied in detail. A…

General Relativity and Quantum Cosmology · Physics 2019-12-12 Vijay Singh , Aroonkumar Beesham

We consider a cosmological model in which the two major fluid components of the Universe, dark energy and dark matter, flow with distinct four-velocities. This cosmological configuration is equivalent to a single anisotropic fluid,…

General Relativity and Quantum Cosmology · Physics 2013-07-24 Tiberiu Harko , Francisco S. N. Lobo

Kantowski-Sachs perfect fluid cosmological model is explored in modified gravity with functional form $f(R, T)$=$f_1(R)$+$f_2(T)$ where $R$ is Ricci scalar, and $T$ is the trace of the energy-momentum tensor. With this functional form,…

General Relativity and Quantum Cosmology · Physics 2023-04-26 T. Vinutha , K. Niharika , K. Sri Kavya

The possibility of obtaining an open set of regular cosmological models is discussed. Cylindrical stiff perfect fluid cosmologies are studied in detail. The condition for geodesic completeness is easy to check. A large family of…

General Relativity and Quantum Cosmology · Physics 2009-04-10 L. Fernández-Jambrina , L. M. González-Romero

We use one of the simplest forms of the K-essence theory and we apply it to the classical anisotropic Bianchi type I cosmological model, with a barotropic perfect fluid modeling the usual matter content and with cosmological constant. The…

General Relativity and Quantum Cosmology · Physics 2014-09-11 J. Socorro , Luis O. Pimentel , Abraham Espinoza-García
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