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Related papers: A fractal LTB model cannot explain Dark Energy

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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

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

I discuss the spherically symmetric but inhomogeneous Lemaitre-Tolman- Bondi (LTB) metric, which provides an exact toy model for an inhomogeneous universe. Since we observe light rays from the past light cone, not the expansion of the…

Astrophysics · Physics 2008-11-26 Kari Enqvist

Do current observational data confirm the assumptions of the cosmological principle, or is there statistical evidence for deviations from spatial homogeneity on large scales? To address these questions, we developed a flexible framework…

Cosmology and Nongalactic Astrophysics · Physics 2014-10-22 Matthias Redlich , Krzysztof Bolejko , Sven Meyer , Geraint F. Lewis , Matthias Bartelmann

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

We start a systematic study of the Lema\^{i}tre-Tolman-Bondi (LTB) model as applied to the large scale structure and its evolution. Here we study three possible initial conditions of the LTB models which are asymptotically FRW at large…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Alexander Gromov , Yurij Baryshev , Daniel J Suson , Pekka Teerikorpi

We address some recent erroneous claim that $H_0$ observations are difficult to accommodate with LTB cosmological models, showing how to construct solutions in agreement with an arbitrary value of $H_0$ by re-writing the exact solution in…

Cosmology and Nongalactic Astrophysics · Physics 2012-12-11 Antonio Enea Romano

Lemaitre-Tolman-Bondi (LTB) solutions are used frequently to describe the collapse or expansion of spherically symmetric inhomogeneous mass distributions in the Universe. These exact solutions are obtained in the synchronous gauge where…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Karel Van Acoleyen

There has been much debate over whether or not one could explain the observed acceleration of the Universe with inhomogeneous cosmological models, such as the spherically-symmetric Lemaitre-Tolman-Bondi (LTB) models. It has been claimed…

Astrophysics · Physics 2009-11-11 R. Ali Vanderveld , Eanna E. Flanagan , Ira Wasserman

It is shown that the observed fractal distribution of galaxies is, in fact, consistent with homogeneity of the Universe and observational limits on $ \Delta T/T$, if the presence of dark matter and dark charge predicted by the Modified…

Astrophysics · Physics 2009-11-07 A. A. Kirillov

The Fractal Bubble model has been proposed as a viable cosmology that does not require dark energy to account for cosmic acceleration, but rather attributes its observational signature to the formation of structure. In this paper it is…

Cosmology and Nongalactic Astrophysics · Physics 2010-01-06 Juliana Kwan , Matthew J. Francis , Geraint F. Lewis

The breakdown of conformal symmetry in a conformally invariant scalar-tensor gravitational model is revisited in the cosmological context. Although the old scenario of conformal symmetry breaking in cosmology containing scalar field has…

General Relativity and Quantum Cosmology · Physics 2013-08-13 F. Darabi

The fractal cosmological model which accounts for observable fractal properties of the Universe's large-scale structure is constructed. In this framework these properties are consequences of the rotary symmetry of charged scalar meson…

Cosmology and Nongalactic Astrophysics · Physics 2012-12-03 I. K. Rozgacheva , A. A. Agapov

In this paper, we explore a fractal model of the universe proposed by Calcagni [JHEP{\bf03}(2010)120] for a power-counting renormalizable field theory living in a fractal spacetime. Considering a timelike fractal profile, we derived field…

General Relativity and Quantum Cosmology · Physics 2022-11-01 Mahnaz Asghari , Ahmad Sheykhi

This article reviews an approach for constructing a simple relativistic fractal cosmology whose main aim is to model the observed inhomogeneities of the distribution of galaxies by means of the Lemaitre-Tolman solution of Einstein's field…

Cosmology and Nongalactic Astrophysics · Physics 2009-10-27 Marcelo B. Ribeiro

The possibility that we live in a special place in the universe, close to the centre of a large void, seems an appealing alternative to the prevailing interpretation of the acceleration of the universe in terms of a LCDM model with a…

Astrophysics · Physics 2009-06-23 Juan Garcia-Bellido , Troels Haugboelle

There is a general agreement that galaxy structures exhibit fractal properties, at least up to some small scale. However the presence of an eventual crossover towards homogenization, as well as the exact value of the fractal dimension, are…

Astrophysics · Physics 2016-08-30 Francesco Sylos Labini

We study cosmological Lemaitre-Tolman-Bondi (LTB) black hole thermodynamics immersed in a quintom universe. We investigate some thermodynamic aspects of such a black hole in detail. We apply two methods of treating particles' tunneling from…

General Relativity and Quantum Cosmology · Physics 2024-09-18 Sareh Eslamzadeh , Kourosh Nozari , J. T. Firouzjaee

Several kinds of astronomical observations, interpreted in the framework of the standard Friedmann-Robertson-Walker cosmology, have indicated that our universe is dominated by a Cosmological Constant. The dimming of distant Type Ia…

Astrophysics · Physics 2014-11-18 Subir Sarkar

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
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