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We consider a variant of the brane-world model in which the universe is the direct product of a Friedmann, Robertson-Walker (FRW) space and a compact hyperbolic manifold of dimension $d\geq2$. Cosmology in this space is particularly…

High Energy Physics - Theory · Physics 2009-10-31 Glenn D. Starkman , Dejan Stojkovic , Mark Trodden

Observational Cosmology has indeed made very rapid progress in the past decade. The ability to quantify the universe has largely improved due to observational constraints coming from structure formation Measurements of CMB anisotropy and,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Tarun Souradeep

We have studied the curvaton scenario in brane world cosmology in an intermediate inflationary scenario. This approach has allowed us to find some constraints on different parameters that appear in the model.

High Energy Physics - Theory · Physics 2011-06-09 H. Farajollahi , A. Ravanpak

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

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 discuss cosmology in four dimensions within a context of brane-world scenario.Such models can predict chaotic inflation with very low reheat temperature depending on the brane tension. We notice that the gravitino abundance is different…

High Energy Physics - Phenomenology · Physics 2009-10-31 Anupam Mazumdar

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

We propose a novel approach to the problem of constraining cosmological initial conditions. Within the framework of effective field theory, we classify initial conditions in terms of boundary terms added to the effective action describing…

High Energy Physics - Theory · Physics 2009-11-11 F. Nitti , M. Porrati , J. -W. Rombouts

We propose a mechanism for solving the horizon and entropy problems of standard cosmology which does not make use of cosmological inflation. Crucial ingredients of our scenario are brane gases, extra dimensions, and a confining potential…

High Energy Physics - Theory · Physics 2007-05-23 Robert Brandenberger , Natalia Shuhmaher

We review results about the development and asymptotic nature of singularities in `brane-bulk' systems. These arise for warped metrics obeying the 5-dimensional Einstein equations with fluid-like sources, and including a brane 4-metric that…

High Energy Physics - Theory · Physics 2017-02-17 Ignatios Antoniadis , Spiros Cotsakis

Astrophysical observations provide a picture of the universe as a 4-dim homogeneous and isotropic flat space-time dominated by an unknown form of dark energy. To achieve such a cosmology one has to consider in the early universe an…

Astrophysics · Physics 2009-11-10 F. Canfora , A. Troisi

In this paper we investigate asymptotic isotropization. We derive the asymptotic dynamics of spatially inhomogeneous cosmological models with a perfect fluid matter source and a positive cosmological constant near the de Sitter equilibrium…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Woei Chet Lim , Henk van Elst , Claes Uggla , John Wainwright

This is an introduction to the ekpyrotic scenario, with an emphasis on the two contexts of brane cosmology and primordial universe scenarios. A self-contained introduction to brane cosmology and a qualitative overview and comparison of the…

Astrophysics · Physics 2007-05-23 Syksy Rasanen

In Brane Gas Cosmology (BGC) the initial state of the universe is taken to be small, dense and hot, with all fundamental degrees of freedom near thermal equilibrium. This starting point is in close analogy with the Standard Big Bang (SBB)…

High Energy Physics - Theory · Physics 2007-05-23 Damien A. Easson

Brane cosmology takes the unconventional form $H\sim \sqrt{\rho}$. To recover the standard cosmology, we have to assume that the matter density is much less than the brane tension. We show that the assumption can be justified even near the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Yungui Gong

A cosmological model for the early time Universe is proposed. In this model, the Universe is a wandering brane moving in a warped throat of a Calabi-Yau space. A non-zero angular momentum induces a turning point in the brane trajectory, and…

High Energy Physics - Theory · Physics 2009-08-13 Cristiano Germani , N. E. Grandi , Alex Kehagias

We present a comprehensive study of the cosmological solutions of 6D braneworld models with azimuthal symmetry in the extra dimensions, moduli stabilization by flux or a bulk scalar field, and which contain at least one 3-brane that could…

High Energy Physics - Theory · Physics 2009-11-10 James M. Cline , Julie Descheneau , Massimo Giovannini , Jérémie Vinet

This contribution presents the cosmological models with extra dimensions that have been recently elaborated, which assume that ordinary matter is confined on a surface, called brane, embedded in a higher dimensional spacetime.

Astrophysics · Physics 2008-11-26 David Langlois

We consider the dynamics of a viscous cosmological fluid in the generalized Randall-Sundrum model for an isotropic brane. To describe the dissipative effects we use the Israel-Hiscock-Stewart full causal thermodynamic theory. In the…

High Energy Physics - Theory · Physics 2008-11-26 Chiang-Mei Chen , T. Harko , M. K. Mak

We consider cosmological solutions and their stability with respect to homogeneous and isotropic perturbations in the braneworld model with the scalar-curvature term in the action for the brane. Part of the results are similar to those…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Dmytro Iakubovskyi , Yuri Shtanov