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Related papers: Singularities on the brane aren't isotropic

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It has recently been suggested that an isotropic singularity may be a generic feature of brane cosmologies, even in the inhomogeneous case. Using the covariant and gauge-invariant approach we present a detailed analysis of linear…

High Energy Physics - Theory · Physics 2009-11-10 Peter K. S. Dunsby , Naureen Goheer , Marco Bruni , Alan Coley

It is argued that the initial cosmological singularity is isotropic in spatially inhomogeneous brane-world models. This implies that brane cosmology may naturally give rise to a set of initial data that provide the conditions for inflation…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Alan Coley

We show that generically the initial singularity is isotropic in spatially homogeneous cosmological models in the brane-world scenario. We then argue that it is plausible that the initial singularity is isotropic in typical brane world…

High Energy Physics - Theory · Physics 2009-11-07 A. Coley

We discuss the asymptotic dynamical evolution of spatially inhomogeneous brane-world cosmological models close to the initial singularity. By introducing suitable scale-invariant dependent variables and a suitable gauge, we write the…

General Relativity and Quantum Cosmology · Physics 2009-11-10 A. A. Coley , Y. He , W. C. Lim

Higher-dimensional braneworld models which contain both bulk and brane curvature terms in the action admit cosmological singularities of rather unusual form and nature. These `quiescent' singularities, which can occur both during the…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Yuri Shtanov , Varun Sahni

We discuss the asymptotic dynamical evolution of spatially homogeneous brane-world cosmological models close to the initial singularity. We find that generically the cosmological singularity is isotropic in Bianchi type IX brane-world…

High Energy Physics - Theory · Physics 2010-04-06 A. Coley

We present the complete set of propagation and constraint equations for the kinematic and non-local first order quantities which describe general linear inhomogeneous and anisotropic perturbations of a flat FRW braneworld with vanishing…

High Energy Physics - Theory · Physics 2009-11-10 Naureen Goheer , Peter K. S. Dunsby , Alan Coley , Marco Bruni

Brane-world cosmology is motivated by recent developments in string/M-theory and offers a new perspective on the hierarchy problem. In the brane-world scenario, our Universe is a four-dimensional subspace or {\em brane} embedded in a…

Astrophysics · Physics 2009-11-11 A. A. Coley

The accelerated expansion of the universe together with its present day isotropy has posed an interesting challenge to the numerous model theories presented over the years to describe them. In this paper, we address the above questions in…

General Relativity and Quantum Cosmology · Physics 2024-11-18 Z. Haghani , H. R. Sepangi , S. Shahidi

We explore the character of finite-time singularities that are possible to arise in FRW universes and in specific braneworld configurations. For FRW universes, we derive a first classification of singularities that is based on the behaviour…

General Relativity and Quantum Cosmology · Physics 2008-06-03 Ifigeneia Klaoudatou

Much work has been devoted to the phenomenology and cosmology of the so-called braneworld universe, where our (3+1)-dimensional universe lies on a brane surrounded by a (4+1)-dimensional bulk spacetime that is essentially empty except for a…

High Energy Physics - Theory · Physics 2009-11-07 Martin Bucher

The braneworld cosmological model was constructed by embedding a 3-brane into a higher dimensional bulk background geometry and the usual matter of our universe was assumed to be confined in the brane while the gravity can propagate in the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Dan-Tao Peng

We study the behavior of spatially homogeneous brane-worlds close to the initial singularity in the presence of both local and nonlocal stresses. It is found that the singularity in these brane-worlds can be locally either isotropic or…

General Relativity and Quantum Cosmology · Physics 2016-08-31 Alan A. Coley , Sigbjorn Hervik

We study cosmological braneworld models with a single timelike extra dimension. Such models admit the intriguing possibility that a contracting braneworld experiences a natural bounce without ever reaching a singular state. This feature…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Yuri Shtanov , Varun Sahni

The behavior near the initial singular state of the anisotropy parameter of the arbitrary type, homogeneous and anisotropic Bianchi models is considered in the framework of the brane world cosmological models. The matter content on the…

General Relativity and Quantum Cosmology · Physics 2009-11-10 T. Harko , M. K. Mak

Several aspects of scalar field dynamics on a brane which differs from corresponding regimes in the standard cosmology are investigated. We consider asymptotic solution near a singularity, condition for inflation and bounces and some detail…

General Relativity and Quantum Cosmology · Physics 2008-11-26 A. V. Toporensky , P. V. Tretyakov , V. O. Ustiansky

We derive a system of cosmological equations for a braneworld with induced curvature which is a junction between several bulk spaces. The permutation symmetry of the bulk spaces is not imposed, and the values of the fundamental constants,…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Yuri Shtanov , Alexander Viznyuk , Luis Norberto Granda

Brane-world singularities are analysed, emphasizing the case of supergravity in singular spaces where the singularity puzzle is naturally resolved. These naked singularities are either time-like or null, corresponding to the finite or…

High Energy Physics - Theory · Physics 2009-11-07 Ph. Brax , A. C. Davis

We present a comprehensive study of cosmological singularities within the framework of Covariant Extrinsic Gravity (CEG), addressing both the initial Big Bang singularity and potential finite-time future singularities. Through detailed…

General Relativity and Quantum Cosmology · Physics 2025-04-08 R. Jalalzadeh , S. Jalalzadeh , Y. Heydarzade

Brane Gas Cosmology (BGC) is an approach to unifying string theory and cosmology in which matter is described by a gas of strings and branes in a dilaton gravity background. The Universe is assumed to start out with all spatial dimensions…

High Energy Physics - Theory · Physics 2009-11-07 Scott Watson , Robert H. Brandenberger
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