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Related papers: Homogeneity, Flatness and "Large" Extra Dimensions

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We propose a model universe in the matter dominated phase described by a FRW background with local inhomogeneities, like our local patch, grown out of the primordial fluctuations. Our sub-horizon local patch consisting of different…

Astrophysics · Physics 2007-05-23 Reza Mansouri

A phenomenological formalism is presented in which the apparent acceleration of the universe is generated by large-scale structure formation, thus eliminating the coincidence and magnitude fine-tuning problems of the Cosmological Constant…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-14 Brett Bochner

Process of formation of the universe with its further expansion in the first evolution stage is investigated in the framework of Friedmann-Robertson-Walker metrics on the basis of quantum model, where a new type of matter is introduced,…

General Relativity and Quantum Cosmology · Physics 2013-01-17 Sergei P. Maydanyuk

We study the classical and quantum models of a flat Friedmann-Robertson-Walker (FRW) space-time, coupled to a perfect fluid, in the context of the consensus and a gauge-fixed Lagrangian frameworks. It is shown that, either in the usual or…

General Relativity and Quantum Cosmology · Physics 2015-03-19 Babak Vakili

Universe structure emerges in the unreduced, complex-dynamic interaction process with the simplest initial configuration (two attracting homogeneous fields, quant-ph/9902015). The unreduced interaction analysis gives intrinsically creative…

General Physics · Physics 2007-05-23 Andrei P. Kirilyuk

The Universe is homogeneous and isotropic on large scales, so on those scales it is usually modelled as a Friedmann-Lema\^{i}tre-Robertson-Walker (FLRW) space-time. The non-linearity of the Einstein field equations raises concern over…

General Relativity and Quantum Cosmology · Physics 2021-03-03 Yonadav Barry Ginat

We demonstrate that the high isotropy of the Cosmic Microwave Background (CMB), combined with the Copernican principle, is not sufficient to prove homogeneity of the universe -- in contrast to previous results on this subject. The crucial…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Chris Clarkson , Richard Barrett

In this paper, we consider the Universe at the late stage of its evolution and deep inside the cell of uniformity. At these scales, the Universe is filled with inhomogeneously distributed discrete structures (galaxies, groups and clusters…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Alvina Burgazli , Maxim Eingorn , Alexander Zhuk

In this paper, we consider the Universe deep inside of the cell of uniformity. At these scales, the Universe is filled with inhomogeneously distributed discrete structures (galaxies, groups and clusters of galaxies), which disturb the…

Cosmology and Nongalactic Astrophysics · Physics 2012-09-25 Maxim Eingorn , Alexander Zhuk

We propose a cosmological model that describes isotropic expansion of inhomogeneous universe. The energy-momentum tensor that creates the spatial inhomogeneity may not affect the uniform expansion scaling factor $a(t)$ in the FLRW-like…

High Energy Physics - Theory · Physics 2014-10-15 Wei-Jian Geng , H. Lu

There are not many tools to quantitatively monitor the emergence of classical geometric features from a quantum spacetime, whose microscopic structure may be a highly quantum-fluctuating "spacetime foam". To improve this situation, we…

High Energy Physics - Theory · Physics 2023-05-10 R. Loll , A. Silva

Old and new puzzles of cosmology are reexamined from the point of view of quantum theory of the universe developed here. It is shown that in proposed approach the difficulties of the standard cosmology do not arise. The theory predicts the…

Astrophysics · Physics 2011-09-13 V. E. Kuzmichev , V. V. Kuzmichev

Is the universe finite or infinite, and what shape does it have? These fundamental questions, of which relatively little is known, are typically studied within the context of the standard model of cosmology where the universe is assumed to…

General Relativity and Quantum Cosmology · Physics 2022-06-02 Gregory J. Galloway , Marcus A. Khuri , Eric Woolgar

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

One of the outstanding problems in general relativistic cosmology is that of the averaging. That is, how the lumpy universe that we observe at small scales averages out to a smooth Friedmann-Lemaitre-Robertson-Walker (FLRW) model. The root…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-21 Tharake Wijenayake , Weikang Lin , Mustapha Ishak

The standard model of cosmology assumes that the Universe can be described to hover around a homogeneous-isotropic solution of Einstein's general theory of relativity. This description needs (sometimes hidden) hypotheses that restrict the…

General Relativity and Quantum Cosmology · Physics 2018-12-21 Thomas Buchert

Quantum theory, general relativity, the standard model of particle physics, and the $\Lambda$CDM model of cosmology have all been spectacularly successful within their respective regimes of applicability, but many central problems remain…

General Physics · Physics 2026-05-26 Roland E. Allen

We consider brane-world models embedded in a five-dimensional bulk spacetime with a large extra dimension and a cosmological constant. The cosmology in $5D$ possesses "wave-like" character in the sense that the metric coefficients in the…

General Relativity and Quantum Cosmology · Physics 2010-01-27 J. Ponce de Leon

In braneworld models a variable vacuum energy may appear if the size of the extra dimension changes during the evolution of the universe. In this scenario the acceleration of the universe is related not only to the variation of the…

General Relativity and Quantum Cosmology · Physics 2015-06-25 J. Ponce de Leon

A cosmological model based on Kaluza-Klein theory is studied. A metric, in which the scale factor of the compact space evolves as an inverse power of the radius of the observable universe, is constructed. The Freedmann-Robertson-Walker…

High Energy Physics - Theory · Physics 2009-11-07 N. Mohammedi