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Related papers: Cosmological models (Carg\`{e}se lectures 1998)

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In this thesis we first apply the 1+3 covariant description of general relativity to analyze n-fluid Friedmann-Lemaitre (FL) cosmologies; that is, homogeneous and isotropic cosmologies whose matter-energy content consists of n…

General Relativity and Quantum Cosmology · Physics 2007-09-26 Paul Ullrich

The 1+3 covariant approach and the covariant gauge-invariant approach to perturbations are used to analyze in depth conformal transformations in cosmology. Such techniques allow us to obtain very interesting insights on the physical content…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Sante Carloni , Emilio Elizalde , Sergei Odintsov

We give a pedagogical review of a covariant and fully non-perturbative approach to study nonlinear perturbations in cosmology. In the first part, devoted to cosmological fluids, we define a nonlinear extension of the uniform-density…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 David Langlois , Filippo Vernizzi

Cosmological models can be studied effectively using dynamical systems techniques. Starting from Brown's formulation of the variational principle for relativistic fluids, we introduce new types of couplings involving a perfect fluid, a…

General Relativity and Quantum Cosmology · Physics 2024-09-13 Christian G. Boehmer , Antonio d'Alfonso del Sordo

In this paper we contrasted two cosmological perturbation theory formalisms, the 1+3 covariant gauge invariant and the gauge invariant by comparing their gauge invariant variables associated with magnetic field defined in each approach. In…

General Relativity and Quantum Cosmology · Physics 2015-11-20 Hector J. Hortua , Leonardo Castañeda

Focus of these lectures is the challenge of explaining the origin of structure in the Universe. The interplay between quantum field theory and classical general relativity has given rise to several interesting cosmological models which…

Astrophysics · Physics 2007-05-23 O. Eboli , V. Ribelles

General relativity marked the beginning of modern cosmology and it has since been at the centre of many of the key developments in this field. In the present review, we discuss the general-relativistic dynamics and perturbations of the…

Astrophysics · Physics 2009-06-23 Christos G. Tsagas , Anthony Challinor , Roy Maartens

The exact 1+3 covariant dynamical fluid equations for a multi-component plasma, together with Maxwell's equations are presented in such a way as to make them suitable for a gauge-invariant analysis of linear density and velocity…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Mattias Marklund , Peter K. S. Dunsby , Gerold Betschart , Martin Servin , Christos Tsagas

Cosmological simulations involving the fully covariant gravitational dynamics may prove relevant in understanding relativistic/non-linear features and, therefore, in taking better advantage of the upcoming large scale structure survey data.…

General Relativity and Quantum Cosmology · Physics 2017-11-15 David Daverio , Yves Dirian , Ermis Mitsou

In recent years there has been a lot of interest in discussing frame dependences/independences of the cosmological perturbations under the conformal transformations. This problem has previously been investigated in terms of the covariant…

General Relativity and Quantum Cosmology · Physics 2018-03-14 Yunlong Zheng , Yicen Mou , Haomin Rao , Mingzhe Li

The purpose of this work is to review, clarify, and critically analyse modern mathematical cosmology. The emphasis is upon mathematical objects and structures, rather than numerical computations. This paper concentrates on general…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Gordon McCabe

We present mathematical details of several cosmological models, whereby the topological and the geometrical background will be emphasized.

General Relativity and Quantum Cosmology · Physics 2007-05-23 H. -J. Schmidt

We present an approach to cosmological perturbations based on a covariant perturbative expansion between two worldlines in the real inhomogeneous universe. As an application, at an arbitrary order we define an exact scalar quantity which…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Kari Enqvist , Janne Hogdahl , Sami Nurmi , Filippo Vernizzi

We use covariant and first-order formalism techniques to study the properties of general relativistic cosmology in three dimensions. The covariant approach provides an irreducible decomposition of the relativistic equations, which allows…

General Relativity and Quantum Cosmology · Physics 2009-11-11 John D. Barrow , Douglas J. Shaw , Christos G. Tsagas

We consider the equivalence problem for cosmological models in four-dimensional gravity theories. A cosmological model is considered as a triple $(M, {\bf g},{\bf u})$ consisting of a spacetime $(M, {\bf g})$ and a preferred normalized…

General Relativity and Quantum Cosmology · Physics 2020-08-03 Lode Wylleman , Alan Coley , David McNutt , Matthew Aadne

The aim of these lecture notes is to familiarize graduate students and beginning postgraduates with the basic ideas of linear cosmological perturbation theory and of structure formation scenarios. We present both the Newtonian and the…

Astrophysics · Physics 2010-12-09 Christos G. Tsagas

We study the evolution of scalar cosmological perturbations in the (1+3)- covariant gauge-invariant formalism for generic $f(R)$ theories of gravity. Extending previous works, we give a complete set of equations describing the evolution of…

General Relativity and Quantum Cosmology · Physics 2012-06-08 Amare Abebe , Mohamed Abdelwahab , Alvaro de la Cruz-Dombriz , Peter K. S. Dunsby

The Ehlers-Ellis 1+3 formulation of covariant hydrodynamics, when supplemented with covariant radiative transport theory, gives an exact, physically transparent description of the physics of the cosmic microwave background radiation (CMB).…

Astrophysics · Physics 2015-06-24 Anthony Challinor

This is a brief review of the standard model of cosmology. We first introduce the FRW models and their flat solutions for energy fluids playing an important role in the dynamics at different epochs. We then introduce different cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2011-11-15 Jorge L. Cervantes-Cota , George Smoot

In this paper we performed investigation of the spatially-flat cosmological models whose spatial section is product of three- ("our Universe") and extra-dimensional parts. The matter source chosen to be the perfect fluid which exists in the…

General Relativity and Quantum Cosmology · Physics 2019-02-11 Sergey A. Pavluchenko
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