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Related papers: Brane-World Cosmology, Bulk Scalars and Perturbati…

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We investigate cosmological evolutions of the bulk scalar field $\phi(t)$ and the radion $d(t)$ in five-dimensional dilatonic two branes model. The bulk potential for the scalar field is taken as the exponential function $V_{bulk} \propto…

High Energy Physics - Theory · Physics 2009-11-07 Shinpei Kobayashi , Kazuya Koyama

A brane world in the presence of a bulk black hole is constructed. The brane tension is fine tuned in terms of the black hole mass and cosmological constant. Gravitational perturbations localized on the brane world are discussed.

High Energy Physics - Theory · Physics 2009-10-31 Cesar Gomez , Bert Janssen , Pedro J. Silva

We derive and solve the full set of scalar perturbation equations for a class of five-dimensional brane--world solutions, with a dilaton scalar field coupled to the bulk cosmological constant and to a 3-brane. The spectrum contains one…

High Energy Physics - Theory · Physics 2007-05-23 V. Bozza , M. Gasperini , G. Veneziano

We examine the dynamics of scalar perturbations in closed Friedmann-Lema\^itre-Robertson- Walker (FLRW) universes in the framework of Brane World theory with a timelike extra dimension. In this scenario, the unperturbed Friedmann equations…

General Relativity and Quantum Cosmology · Physics 2014-12-16 Rodrigo Maier , Francesco Pace , Ivano Damião Soares

We consider real and complex scalar fields non-minimally coupled to gravity in the bulk spacetime and study their impact on the brane upon acquiring a non-vanishing vacuum expectation value. When examining the case of the complex scalar…

High Energy Physics - Theory · Physics 2008-11-26 Orfeu Bertolami , Carla Carvalho

We show that a four-dimensional equation of state for a cosmological constant term arises from a perfect fluid in the bulk in the context of a gravity model where the scalar curvature is non-minimally coupled to the perfect fluid Lagrangian…

High Energy Physics - Theory · Physics 2010-05-28 Orfeu Bertolami , Carla Carvalho , Joao Laia

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

This work revises the Brane World Theory known as Randall-Sundrum with the modification of an exponential, redshift-dependent brane tension. This model is studied in a scenario assuming no dark energy, with the aim of determining whether it…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-27 Kyra Jacobo , Dorian Araya

We give a short review of the recent development in the investigation of the vacuum expectation values of the bulk and surface energy-momentum tensors generated by quantum fluctuations of a massive scalar field with general curvature…

High Energy Physics - Theory · Physics 2007-05-23 Aram A. Saharian

We study the thermodynamics of some cosmological models based on modified gravity, a braneworld with induced gravity and curvature effect. Dark energy component seems necessary if the models are to approach thermal equilibrium in the long…

General Relativity and Quantum Cosmology · Physics 2011-09-16 Ninfa Radicella , Diego Pavón

We construct a model where cosmological perturbations are analytically solved based on dilatonic brane worlds. A bulk scalar field has an exponential potential in the bulk and an exponential coupling to the brane tension. The bulk scalar…

High Energy Physics - Theory · Physics 2009-11-10 Kazuya Koyama , Keitaro Takahashi

A model of an emergent universe is obtained in brane world. Here the bulk energy is in the form of cosmological constant, while the brane consists of a fluid satisfying an equation of state of the form $p_{b}={1/3} \rho_{b}$, which is…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Asit Banerjee , Tanwi Bandyopadhyay , Subenoy Chakraborty

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

We develop a four-dimensional effective theory for Randall-Sundrum models which allows us to calculate long wavelength adiabatic perturbations in a regime where the $\rho ^2$ terms characteristic of braneworld cosmology are significant.…

High Energy Physics - Theory · Physics 2009-11-10 Claudia de Rham

We investigate the cosmological dynamics of a brane Universe when quantum corrections from vacuum polarization are taken into account. New vacuum de Sitter points existing on Randall-Sundrum brane are described. We show also that quantum…

General Relativity and Quantum Cosmology · Physics 2007-05-23 A. V. Toporensky , P. V. Tretyakov

We consider the brane-world in the holographic point of view. Bearing the realistic models in mind, the bulk massless scalar field is introduced. First of all, we find the constraint on the coupling of the scalar fields with the matter(not…

High Energy Physics - Theory · Physics 2014-11-18 Tetsuya Shiromizu , Takashi Torii , Daisuke Ida

The most remarkable and interesting feature of brane world scenario is the use of bulk's curvature to localize gravity on the brane, albeit with fine tuning of the brane and bulk parameters. For FRW expanding universe on the brane, it is a…

High Energy Physics - Theory · Physics 2009-11-07 Parampreet Singh , Naresh Dadhich

We develop a gauge-invariant formalism to describe metric perturbations in five-dimensional brane-world theories. In particular, this formalism applies to models originating from heterotic M-theory. We introduce a generalized longitudinal…

High Energy Physics - Theory · Physics 2008-11-26 C. van de Bruck , M. Dorca , R. H. Brandenberger , A. Lukas

We investigated the effects of bulk scalar field in the braneworld cosmological scenario. The Friedmann equations and acceleration condition in presence of the bulk scalar field for a zero tension brane and cosmological constant are…

General Relativity and Quantum Cosmology · Physics 2011-07-19 Rizwan ul Haq Ansari , P. K. Suresh

We argue that the brane-world picture with matter-fields confined to 4-d domain walls and with gravitational interactions across the bulk disallows adding an arbitrary constant to the low-energy, 4-d effective theory -- which finesses the…

High Energy Physics - Theory · Physics 2009-09-15 Paul J. Steinhardt
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