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Related papers: Variable Brane Tension and Dark Energy

200 papers

Recent observations provide strong evidence that the universe is accelerating. This confronts theory with a severe challenge. Explanations of the acceleration within the framework of general relativity are plagued by difficulties. General…

Astrophysics · Physics 2008-11-26 Roy Maartens

The assumption that our Universe is close to a late time fixed point of the equations of cosmology, leads to a modification of the latter to include energy exchange between the matter and the "dark energy". The brane-world scenario provides…

High Energy Physics - Phenomenology · Physics 2007-05-23 Theodore N. Tomaras

Braneworld models have been proposed as a possible solution to the problem of the accelerated expansion of the Universe. The idea is to dispense the dark energy (DE) and drive the late-time cosmic acceleration with a five-dimensional…

General Relativity and Quantum Cosmology · Physics 2018-06-13 Miguel A. Garcia-Aspeitia , A. Hernandez-Almada , Juan Magaña , Mario H. Amante , V. Motta , C. Martínez-Robles

Braneworld models with variable brane tension $\lambda $ introduce a new degree of freedom that allows for evolving gravitational and cosmological constants, the latter being a natural candidate for dark energy. We consider a thermodynamic…

General Relativity and Quantum Cosmology · Physics 2011-03-28 K. C. Wong , K. S. Cheng , T. Harko

We consider the cosmological evolution of a brane for general bulk matter content. In our setup the bulk pressure and the energy exchange densities are comparable to the brane energy density. Adopting a phenomenological fluid ansatz and…

High Energy Physics - Theory · Physics 2008-11-26 C. Bogdanos , K. Tamvakis

In this letter, dark energy is obtained using dual roles of the Ricci scalar (as a physical field as well as geometry). Dark energy density, obtained here, mimics phantom and the derived Friedmann equation contains a term $\rho^2_{\rm de}/2…

High Energy Physics - Theory · Physics 2008-11-26 S. K. Srivastava

Adopting Dirac's brane variation prescription, the energy-momentum tensor of a brane gets supplemented by a geometrical (embedding originated) dark component. While the masslessness of the graviton is preserved, and the Newton force law is…

General Relativity and Quantum Cosmology · Physics 2010-02-17 Ilya Gurwich , Aharon Davidson

We construct a DGP-inspired braneworld model where induced gravity on the brane is modified in the spirit of $f(R)$ gravity and stringy effects are taken into account by incorporation of the Gauss-Bonnet term in the bulk action. We explore…

General Relativity and Quantum Cosmology · Physics 2009-09-28 Kourosh Nozari , Narges Rashidi

Two problems related to dark matter is considered in the context of a brane world model in which the confinement of gauge fields on the brane is achieved by invoking a confining potential. First, we show that the virial mass discrepancy can…

General Relativity and Quantum Cosmology · Physics 2024-11-18 Shahab Shahidi , Hamid Reza Sepangi

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 the Chaplygin gas with the modified equation of state such as $p=A\rho-B/\rho$. Initially…

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

The Friedmann law on the brane generically depends quadratically on the brane energy density and involves a ``dark radiation'' term due to the bulk Weyl tensor. Despite its unfamiliar form, we show how it can be derived from a standard…

High Energy Physics - Theory · Physics 2009-11-07 J. Khoury , R. -J. Zhang

The paper deals with a spatially homogeneous and isotropic FRW space-time filled with perfect fluid and dark energy components. The two sources are assumed to interact minimally, and therefore their energy momentum tensors are conserved…

General Relativity and Quantum Cosmology · Physics 2014-08-21 Suresh Kumar

We analyze, within the framework of unified brane gravity, the weak-field perturbations caused by the presence of matter on a 3-brane. Although deviating from the Randall-Sundrum approach, the masslessness of the graviton is still…

High Energy Physics - Theory · Physics 2009-08-13 Ilya Gurwich , Aharon Davidson

We consider a brane cosmological model with energy exchange between brane and bulk. Parameterizing the energy exchange term by the scale factor and Hubble parameter, we are able to exactly solve the modified Friedmann equation on the brane.…

High Energy Physics - Theory · Physics 2008-11-26 Rong-Gen Cai , Yungui Gong , Bin Wang

We show that for an RSII braneworld filled with interacting viscous dark energy and dark matter, one can always rewrite the Friedmann equation in the form of the first law of thermodynamics, $dE=T_hdS_h+WdV$, at apparent horizon. In…

General Physics · Physics 2015-05-27 M. R. Setare , A. Sheykhi

The role of brane-bulk energy exchange and of an induced gravity term on a single braneworld of negative tension and vanishing effective cosmological constant is studied. It is shown that for the physically interesting cases of dust and…

High Energy Physics - Theory · Physics 2009-11-11 G. Kofinas , G. Panotopoulos , T. N. Tomaras

We consider the generalized particle dynamics, proposed by us, in brane world formalisms for an asymptotically anti de Sitter background. The present framework results in a new model that accounts for the late acceleration of the universe.…

Cosmology and Nongalactic Astrophysics · Physics 2011-07-25 Sudipta Das , Subir Ghosh , Jan-Willem van Holten , Supratik Pal

The present work is a second in the series of investigation of the background dynamics in brane cosmology when dark energy is coupled to dark matter by a suitable interaction. Here, dark matter is chosen in the form of perfect fluid with…

General Physics · Physics 2019-06-21 Sujay Kr. Biswas , Subenoy Chakraborty

We construct a new brane-world model composed of a bulk -with a dilatonic field-, plus a brane -with brane tension coupled to the dilaton-, cold dark matter and an induced gravity term. It is possible to show that depending on the nature of…

High Energy Physics - Theory · Physics 2011-02-07 Mariam Bouhmadi-Lopez , Antonio Ferrera

We propose a new unified model that describes~dark energy and dark matter in the context of $f(R,\phi )$ gravity using a massive scalar field in five dimensions. The scalar field is considered in the bulk that surrounds the 3-brane in…

General Relativity and Quantum Cosmology · Physics 2021-05-13 M. Bousder , Z. Sakhi , M. Bennai
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