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Related papers: Brane-Universes with Variable G and Lambda

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The prevailing cosmological model with the lambda-term, in which the space is flat, is studied (section 1). The corresponding age of the Universe (t0) is calculated (assuming a Hubble constant consistent with the measurements of the Hubble…

Astrophysics · Physics 2009-09-29 Evangelos Chaliasos

We consider the cosmology of a 3-brane universe, in a five dimensional space time (Bulk). We present some solutions to the five-dimensional Einstein equation, where a perfect fluid is confined to the 3-brane. We investigate the evolution of…

General Relativity and Quantum Cosmology · Physics 2010-06-10 Kh. Saaidi , A. Mohammadi

In the context of a five-dimensional theory with a scalar field non-minimally-coupled to gravity, we look for solutions that describe novel black-string or maximally-symmetric solutions in the bulk. The brane line-element is found to…

General Relativity and Quantum Cosmology · Physics 2018-10-09 Panagiota Kanti , Theodoros Nakas , Nikolaos Pappas

D-branes, topological defects in string theory on which string endpoints can live, may give new insight into the understanding of the cosmological evolution of the Universe at early epochs. We analyze the dynamics of D-branes in curved…

High Energy Physics - Theory · Physics 2009-10-31 Michele Maggiore , Antonio Riotto

We study a theory of dilaton gravity in a 5-dimensional brane scenario, with a non-minimal coupling of the dilaton to the matter content of the universe localized on the brane. The effective gravitational equations at the brane are derived…

High Energy Physics - Theory · Physics 2011-12-21 Dominika Konikowska

These notes give an introductory review on brane cosmology. This subject deals with the cosmological behaviour of a brane-universe, i.e. a three-dimensional space, where ordinary matter is confined, embedded in a higher dimensional…

High Energy Physics - Theory · Physics 2008-11-26 David Langlois

This paper explores models of the FLRW universe that incorporate a time-varying cosmological term $\Lambda(t)$. Specifically, we assume a power-law form for the cosmological term as a function of the scale factor: $\Lambda(t)=\Lambda_{0}…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-14 M. Koussour , N. Myrzakulov , J. Rayimbaev

A new class of exact solutions of Einstein's field equations with a perfect fluid source, variable gravitational coupling $G$ and cosmological term $\Lambda$ for FRW spacetime is obtained by considering variable deceleration parameter…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Anirudh Pradhan , Ajay Kumar Singh , Saeed Otarod

We have considered a cosmological model of the FRW universe with variable $G$ and $\Lambda$. The solutions have been obtained for flat model with particular form of cosmological constant. The cosmological parameters have also been obtained…

General Relativity and Quantum Cosmology · Physics 2011-03-31 Mubasher Jamil , Ujjal Debnath

The Cosmological Problem is considered in a five-dimensional (bulk) manifold with two time coordinates, obeying vacuum Einstein field equations. The evolution formalism is used there, in order to get a simple form of the resulting…

General Relativity and Quantum Cosmology · Physics 2019-02-27 Carles Bona , Miguel Bezares , Bartolomé Pons-Rullan , Daniele Viganò

We consider a recently proposed setup where a codimension one brane is embedded in the background of a smooth domain wall interpolating between AdS and Minkowski minima. Since the volume of the transverse dimension is infinite, bulk…

High Energy Physics - Theory · Physics 2009-10-31 Zurab Kakushadze

We explore the possibility of generalizing the locally localized gravity model in five space-time dimensions to arbitrary higher dimensions. In a space-time with negative cosmological constant, there are essentially two kinds of…

High Energy Physics - Theory · Physics 2009-11-07 Ichiro Oda

Through modeling the universe as a symplectic 3-brane embedded in the bulk of N = 2 five-dimensional ungauged supergravity theory, the entire evolution of the universe can be interpreted from inflation to late-time acceleration without…

General Relativity and Quantum Cosmology · Physics 2023-04-19 Moataz H. Emam , Safinaz Salem

We consider a multidimensional cosmological model with FRW type metric having 4-dimensional space-time and $d$-dimensional Ricci-flat internal space sectors with a higher dimensional cosmological constant. We study the classical cosmology…

General Relativity and Quantum Cosmology · Physics 2015-06-05 K. Zeynali , F. Darabi , H. Motavalli

We canonically quantize the dynamics of the brane universe embedded into the five-dimensional Schwarzschild-anti-deSitter bulk space-time. We show that in the brane-world settings the formulation of the quantum cosmology, including the…

General Relativity and Quantum Cosmology · Physics 2009-11-10 A. Boyarsky , A. Neronov , I. Tkachev

The evolution of universe in Brans-Dicke (BD) theory is discussed in this paper. Considering a parameterized scenario for BD scalar field $\phi=\phi_{0}a^{\alpha}$ which plays the role of gravitational "constant" $G$, we apply the Markov…

Cosmology and Nongalactic Astrophysics · Physics 2011-10-14 Jianbo Lu , Weiping Wang , Lixin Xu , Yabo Wu

A cosmological scenario with two branes (A and B) moving in a 5-dimensional bulk is considered. As in the case of ecpyrotic and born-again braneworld models it is possible that the branes collide. The energy-momentum tensor is taken to…

General Relativity and Quantum Cosmology · Physics 2009-11-10 P. Kuusk , M. Saal

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

Braneworld scenarios consider our observable universe as a brane embedded in a 5D space, named bulk. In this work, I derive the field equations of a braneworld model in a generalized theory of gravitation, namely $f(R,T)$ gravity, with $R$…

General Relativity and Quantum Cosmology · Physics 2016-02-17 P. H. R. S. Moraes , R. A. C. Correa

The cosmology of the Horava-Witten M-Theory reduced to five dimensions retaining the volume modulus is considered. Brane matter is considered as a perturbation on the vacuum solution, and the question of under what circumstances does the…

High Energy Physics - Theory · Physics 2007-05-23 R. Arnowitt , James Dent , B. Dutta