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

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We obtain the entropy of a homogeneous anisotropic universe applicable, by assumption, to the fractional branes in the universe in the model of Chowdhury and Mathur. The entropy for the 3 or 4 charge fractional branes thus obtained is not…

High Energy Physics - Theory · Physics 2008-11-26 S. Kalyana Rama

We show that modelling the universe as a pre-geometric system with emergent quantum modes, and then constructing the classical limit, we obtain a new account of space and gravity that goes beyond Newtonian gravity even in the…

General Physics · Physics 2007-09-20 Reginald T Cahill

The Cosmological Principle, which states that the Universe is homogeneous and isotropic (when averaged on large scales), is the foundational assumption of Friedmann-Lemaitre-Robertson-Walker (FLRW) cosmologies such as the current standard…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-15 Nathan Secrest , Sebastian von Hausegger , Mohamed Rameez , Roya Mohayaee , Subir Sarkar

We propose a model of the Universe based on Minkowski flat space-time metric. In this model the space-time does not evolve. Instead the matter evolves such that all the mass parameters increase with time. We construct a model based on…

Cosmology and Nongalactic Astrophysics · Physics 2012-11-15 Pankaj Jain

A cosmological model with an inhomogeneous viscous dark fluid coupled with dark matter in a flat Friedman-Robertson-Walker universe is investigated. The influence of dark matter on the behavior of an inhomogeneous viscous fluid of this…

General Relativity and Quantum Cosmology · Physics 2015-06-22 E. Elizalde , V. V. Obukhov , A. V. Timoshkin

We perform large-scale cosmological simulations that solve Einstein's equations directly via numerical relativity. Starting with initial conditions sampled from the cosmic microwave background, we track the emergence of a cosmic web without…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-27 Hayley J. Macpherson , Daniel J. Price , Paul D. Lasky

A static Friedmann brane in a 5-dimensional bulk (Randall-Sundrum type scenario) can have a very different relation between the density, pressure, curvature and cosmological constant than in the case of the general relativistic Einstein…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Laszlo Gergely , Roy Maartens

A new model of the observed universe, using solutions to the full Einstein equations, is developed from the hypothesis that our observable universe is an underdense bubble, with an internally inhomogeneous fractal bubble distribution of…

General Relativity and Quantum Cosmology · Physics 2007-05-23 David L. Wiltshire

We have studied the inhomogeneous cosmology in Kaluza-Klein spacetime with a positive cosmological constant in a dust dominated era ($p = 0$). Depending on the integration constant we have derived two types of solutions. The dimensional…

General Relativity and Quantum Cosmology · Physics 2025-02-27 D. Panigrahi , S. Chatterjee

We present a brief history of the construction of models of the universe, followed by calculations of quantitative characteristics of basic geometric and kinematic properties of the Standard Cosmological Model ($\Lambda$CDM). Using the…

General Relativity and Quantum Cosmology · Physics 2026-04-23 D. I. Nagirner , S. G. Jorstad , A. V. Dementyev

A fully realistic and systematic effective field theory model of a 3-brane universe is constructed. It consists of a six-dimensional gravitating spacetime, containing several, approximately parallel (3+1)-dimensional defects, or…

High Energy Physics - Phenomenology · Physics 2009-09-15 Raman Sundrum

Specific dark energy models with a linear inhomogeneous time-dependent equation of state, within the framework of 4d Friedman-Robertson-Walker (FRW) cosmology, are investigated. It is demonstrated that such 4d inhomogeneous fluid models may…

General Relativity and Quantum Cosmology · Physics 2014-01-28 I. Brevik , A. V. Timoshkin , Ye. Rabochaya , S. Zerbini

We discuss theories in which the standard-model particles are localized on a brane embedded in space-time with large compact extra dimensions, whereas gravity propagates in the bulk. In addition to the ground state corresponding to a…

High Energy Physics - Theory · Physics 2010-11-19 G. Dvali , M. Shifman

The standard Friedmann universe embedded in a five dimensional and constant curvature bulk is examined without any a priori junction condition between the brane and the bulk. A geometrical explanation for the accelerated expansion of the…

Astrophysics · Physics 2008-11-26 M. D. Maia , Edmundo M. Monte , J. M. F. Maia

Inflationary models are generally credited with explaining the large scale homogeneity, isotropy, and flatness of our universe as well as accounting for the origin of structure (i.e., the deviations from exact homogeneity) in our universe.…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Stefan Hollands , Robert M. Wald

Evidence for almost spatial flatness of the Universe has been provided from several observational probes, including the Cosmic Microwave Background (CMB) and Baryon Acoustic Oscillations (BAO) from galaxy clustering data. However, other…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-14 Raul Jimenez , Ali Rida Khalife , Daniel F. Litim , Sabino Matarrese , Benjamin D. Wandelt

General relativistic corrections to the expansion rate of the Universe arise when the Einstein equations are averaged over a spatial volume in a locally inhomogeneous cosmology. It has been suggested that they may contribute to the observed…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-01 Xinghai Zhao , Grant J. Mathews

The great emptiness is a possible beginning of the Universe in the infinite past of physical time. For the epoch of great emptiness particles are extremely rare and effectively massless. Only expectation values of fields and average…

General Relativity and Quantum Cosmology · Physics 2021-05-12 C. Wetterich

There is now strong evidence that the current energy density of the Universe is dominated by dark energy with an equation of state w<-1/3, which is causing accelerated expansion. The build-up of structure within such Universes is subject to…

Astrophysics · Physics 2008-11-26 Will J. Percival

In this paper we propose a higher dimensional Cosmology based on FRW model and brane-world scenario. We consider the warp factor in the brane-world scenario as a scale factor in 5-dimensional generalized FRW metric, which is called as bulk…

General Relativity and Quantum Cosmology · Physics 2011-04-22 M. Mohsenzadeh , E. Yusofi
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