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Related papers: Relativistic Fractal Cosmologies

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This paper presents numerical solutions of particular Lemaitre-Tolman models approximating a fractal behaviour along the past light cone, as discussed in paper I (0807.0866) of this series. The initial conditions of the numerical problem…

Astrophysics · Physics 2011-02-11 Marcelo B. Ribeiro

This work examines a relativistic model for the observed inhomogeneities of the large scale structure where the hypothesis that this structure can be described as being a self-similar fractal system is advanced. The concept of hierarchical…

Astrophysics · Physics 2011-02-11 Marcelo B. Ribeiro

This paper studies the spatially homogeneous Einstein-de Sitter cosmological model in the context of a relativistic hierarchical (fractal) cosmology as developed in paper I (0807.0866). The Einstein-de Sitter model is treated as a special…

Astrophysics · Physics 2011-02-11 Marcelo B. Ribeiro

This paper presents an analysis of the smoothness problem in cosmology by focussing on the ambiguities originated in the simplifying hypotheses aimed at observationally verifying if the large-scale distribution of galaxies is homogeneous,…

Astrophysics · Physics 2015-06-24 Marcelo B. Ribeiro

This work provides a general discussion of the spatially inhomogeneous Lema\^itre-Tolman-Bondi (LTB) cosmology, as well as its basic properties and many useful relevant quantities, such as the cosmological distances. We apply the concept of…

General Relativity and Quantum Cosmology · Physics 2013-12-19 Felipe A. M. G. Nogueira

The two-point correlation function for the dust distribution in the unperturbed Einstein-de Sitter cosmological model is studied along the past light cone. It was found that this function seems unable to represent the theoretical…

Astrophysics · Physics 2009-10-31 Marcelo B. Ribeiro

We present a new model universe based on the junction of FRW to flat Lemaitre-Tolman-Bondi (LTB) solutions of Einstein equations along our past light cone, bringing structures within the FRW models. The model is assumed globally to be…

Astrophysics · Physics 2008-11-26 Sh. Khosravi , E. Kourkchi , R. Mansouri , Y. Akrami

This thesis concerns the compatibility of inhomogeneous cosmologies with our present understanding of the universe. It is a problem of some interest to find the class of all relativistic cosmological models which are capable of providing a…

Astrophysics · Physics 2007-05-23 Chris A. Clarkson

This paper presents a review of the fractal approach for describing the large scale distribution of galaxies. We start by presenting a brief, but general, introduction to fractals, which emphasizes their empirical side and applications…

Astrophysics · Physics 2022-05-10 Marcelo B. Ribeiro , Alexandre Y. Miguelote

Motivated by the dawn of precision cosmology and the wealth of forthcoming high precision and volume galaxy surveys, in this paper we study the effects of inhomogeneities on light propagation in a flat \Lambda CDM background. To this end we…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-19 Nikolai Meures , Marco Bruni

Many recent researches have investigated the deviations from the Friedmannian cosmological model, as well as their consequences on unexplained cosmological phenomena, such as dark matter and the acceleration of the Universe. On the one…

General Relativity and Quantum Cosmology · Physics 2021-09-22 Sergio Cacciatori , Alessio Marrani , Federico Re

We present a cosmological model in which the metric allows for an inhomogeneous Universe with no intrinsic symmetries (Stephani models), providing the ideal features to describe a fractal distribution of matter. Constraints on the metric…

Astrophysics · Physics 2009-11-07 Fulvio Pompilio , Marco Montuori

This paper seeks to check the validity of the "apparent fractal conjecture" (Ribeiro 2001ab: gr-qc/9909093, astro-ph/0104181), which states that the observed power-law behaviour for the average density of large-scale distribution of…

Astrophysics · Physics 2014-10-13 Elcio Abdalla , Roya Mohayaee , Marcelo B. Ribeiro

The inhomogeneous distribution of matter in the non-linear regime of galaxies, clusters of galaxies and voids is described by an exact, spherically symmetric inhomogeneous solution of Einstein's gravitational field equations, corresponding…

Astrophysics · Physics 2009-11-11 J. W. Moffat

We develop a new approach to building cosmological models, in which small pieces of perturbed Minkowski space are joined together at reflection-symmetric boundaries in order to form a global, dynamical space-time. Each piece of this…

General Relativity and Quantum Cosmology · Physics 2016-04-12 Viraj A. A. Sanghai , Timothy Clifton

We construct an exact relativistic cosmology in which an inhomogeneous but isotropic local region has fractal number counts and matches to a homogeneous background at a scale of the order of $10^2$ Mpc. We show that Einstein's equations and…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Neil Humphreys , David Matravers , Roy Maartens

The idea of the global gravitational effect as the source of cosmological redshift was considered by de Sitter (1916, 1917), Eddington (1923), Tolman (1929) and Bondi (1947). Also Hubble (1929) called the discovered distance-redshift…

General Relativity and Quantum Cosmology · Physics 2016-10-24 Yu. V. Baryshev

In this paper we attempt to answer to the question: can cosmic acceleration of the Universe have a fractal solution? We give an exact solution of a Lema\^itre-Tolman-Bondi (LTB) Universe based on the assumption that such a smooth metric is…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-30 Leonardo Cosmai , Giuseppe Fanizza , Francesco Sylos Labini , Luciano Pietronero , Luigi Tedesco

Recently, inhomogeneous generalisations of the Friedmann-Lemaitre-Robertson-Walker cosmological models have gained interest in the astrophysical community and are more often employed to study cosmological phenomena. However, in many papers…

Cosmology and Nongalactic Astrophysics · Physics 2011-10-17 Krzysztof Bolejko , Marie-Noëlle Célérier , Andrzej Krasiński

Two-point correlation function of galaxy distribution shows that the structure in the present Universe is scale-free up to a certain scale (at least several tens Mpc), which suggests that a fractal structure may exist. If small primordial…

Astrophysics · Physics 2009-10-31 Takayuki Tatekawa , Kei-ichi Maeda
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