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Related papers: Exact Cosmological Solutions in Modified Brans-Dic…

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In this paper we discuss classical and quantum aspects of cosmological models in Brans-Dicke theory. First, we review cosmological bounce solution in Brans-Dicke theory that obeys energy conditions (without ghost) for a universe filled with…

General Relativity and Quantum Cosmology · Physics 2021-08-09 Carla R. Almeida , O. Galkina , J. C. Fabris

In this paper, we have investigated late time acceleration for a spatially flat dust filled Universe in Brans-Dicke theory in the presence of a positive cosmological constant $\Lambda$ . Expressions for Hubble's constant, luminosity…

General Relativity and Quantum Cosmology · Physics 2017-10-23 G. K. Goswami

Brans-Dicke cosmological models for a spatially isotropic and homogeneous universe are tested in terms of the validity of the Generalized Second Law of Thermodynamics (GSL). The investigation is carried out in the Einstein frame. It is…

General Relativity and Quantum Cosmology · Physics 2022-05-19 Tanima Duary , Narayan Banerjee

Exact solutions are studied in the context of modified Brans-Dicke theory. The non-linearity of the modified Brans-Dicke field equations is treated with the Euler-Duarte-Moreira method of integrability of anharmonic oscillator equation.…

General Relativity and Quantum Cosmology · Physics 2019-08-19 Purba Mukherjee , Soumya Chakrabarti

A class of cosmological solutions of higher dimensional Einstein field equations with the energy-momentum tensor of a homogeneous, isotropic fluid as the source are considered with an anisotropic metric that includes the direct sum of a…

General Relativity and Quantum Cosmology · Physics 2013-10-24 Ozgur Akarsu , Tekin Dereli

We study the cosmology of the Brans-Dicke theory with perfect fluid type matter. In our previous work, we found exact solutions for any Brans-Dicke parameter $\omega$ and for general parameter $\gamma$ of equation of state. In this paper we…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Chanyong Park , Sang-Jin Sin

Higher dimensional, static, cylindrically symmetric vacuum solutions with and without a cosmological constant in the Brans-Dicke theory are presented. We show that, for a negative cosmological constant and for specific values of the…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Ahmet Baykal , Dilek K. Ciftci , Ozgur Delice

Gravitational effective theories associated with holographic CFTs have cosmological solutions, which are typically big-bang / big-crunch cosmologies. These solutions are not asymptotically AdS, so they are not dual to finite-energy states…

High Energy Physics - Theory · Physics 2023-06-26 Abhisek Sahu , Petar Simidzija , Mark Van Raamsdonk

In this paper, by establishing a Brans-Dicke (BD) cosmology by means of a deformed phase space, in the absence of any scalar potential, cosmological constant and ordinary matter, we show that it is feasible to overcome obstacles reported in…

General Relativity and Quantum Cosmology · Physics 2019-02-13 S. M. M. Rasouli , J. Marto , P. V. Moniz

We construct a time dependent adjustment mechanism for the cosmological "constant" which could be at work in a late Friedmann-Robertson-Walker universe dominated by quintessence and matter. It makes use of a Brans-Dicke field that couples…

High Energy Physics - Phenomenology · Physics 2009-02-20 A. Hebecker , C. Wetterich

Brans-Dicke cosmology with an (inverse) power-law potential is revisited in the light of modern quintessence and inflation models. A simple ansatz relating scale factor and scalar field recovers most of the known solutions and generates new…

General Relativity and Quantum Cosmology · Physics 2018-04-04 Dilek K. Ciftci , Valerio Faraoni

In the standard model of cosmology, the universe is described by a Robertson-Walker spacetime, while its matter/energy content is modeled by a perfect fluid with three components corresponding to matter/dust, radiation and a cosmological…

General Relativity and Quantum Cosmology · Physics 2013-06-14 Thomas-Paul Hack

We study the cosmology of the Brans-Dicke(BD) theory coupled to perfect fluid type matter. In our previous works, the case where matter is coming from the Ramond-Ramond sector of the string theory was studied. Here, we study the case where…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Sunggeun Lee , Chanyong Park , Sang-Jin Sin

We analyze Brans-Dicke gravity with a cosmological constant, $\Lambda$, and cold dark matter (BD-$\Lambda$CDM for short) in the light of the latest cosmological observations on distant supernovae, Hubble rate measurements at different…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-25 Joan Sola , Adria Gomez-Valent , Javier de Cruz Perez , Cristian Moreno-Pulido

We investigate an exact solution that describes the embedding of the four-dimensional (4D) perfect fluid in a five-dimensional (5D) Einstein spacetime. The effective metric of the 4D perfect fluid as a hypersurface with induced matter is…

High Energy Physics - Theory · Physics 2008-11-26 Jie Ren , Xin-He Meng , Liu Zhao

The pure Brans-Dicke (BD) gravity with or without the cosmological constant $\Lambda $ has been taken as a model theory for the dark matter. Indeed, there has been a consensus that unless one modifies either the standard theory of gravity,…

Astrophysics · Physics 2007-08-21 Hongsu Kim

In a Brans-Dicke (BD) cosmological model, the energy density associated with some scalar field decreases as $\displaystyle a^{{-2}(\frac{\omega_{o}+ {\frac12}%}{\omega_{o}+1})} $ with the scale factor $a(t)$ of the Universe, giving a matter…

Astrophysics · Physics 2009-10-31 S. del Campo , N. Cruz

We present self-similar cosmological solutions for a barotropic fluid plus scalar field with Brans-Dicke-type coupling to the spacetime curvature and an arbitrary power-law potential energy. We identify all the fixed points in the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Damien J. Holden , David Wands

Following recent fit of supernovae data to Brans-Dicke theory which favours the model with $\omega = - 3/2$ \cite{fabris} we discuss the status of this special case of Brans-Dicke cosmology in both isotropic and anisotropic framework. It…

High Energy Physics - Theory · Physics 2008-11-26 Mariusz P. Dabrowski , Tomasz Denkiewicz , David Blaschke

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