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Related papers: A Study of the Time Evolution of Brans-Dicke Param…

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A theoretical model of cosmic expansion has been formulated on an assumption of inter-conversion of matter and dark energy, in the framework of Brans-Dicke theory. An empirical scale factor has been used, which generates a signature flip of…

General Relativity and Quantum Cosmology · Physics 2017-11-07 Sudipto Roy , Dibyajyoti Laha , Argho Aranya Sangma , Indrani Pal

The present study, on the expansion of universe, is based on an assumption regarding the possibility of inter-conversion between matter and dark energy, through some interaction of matter with the scalar field in the framework of…

General Relativity and Quantum Cosmology · Physics 2017-11-07 Sudipto Roy , Mohsin Islam

The present study is based on a generalized form of Brans-Dicke (BD) theory where, the dimensionless BD parameter is regarded as a function of the scalar field, which is reciprocal of the gravitational constant. The field equations have…

General Relativity and Quantum Cosmology · Physics 2017-11-07 Sudipto Roy

In the framework of Brans-Dicke (BD) theory, the first part of the present study determines the time dependence of BD parameter, energy density and equation of state (EoS) parameter of the cosmic fluid in a universe expanding with…

General Relativity and Quantum Cosmology · Physics 2019-05-13 Sudipto Roy , Dipika Nandi , Sumana Ghosh , Apashanka Das

We have studied the time dependence of w for an expanding universe in the generalised B-D theory and have obtained its explicit dependence on the nature of matter contained in the universe,in different era.Lastly we discuss how the observed…

General Relativity and Quantum Cosmology · Physics 2009-11-07 B. K. Sahoo , L. P. Singh

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

The present paper reports a study on the dimensionless parameter $\omega$ in Brans-Dicke theory. Based on a particular choice of scale factor $a$, we have investigated the signature flip of the deceleration parameter $q$ to see whether the…

General Relativity and Quantum Cosmology · Physics 2013-12-11 Sudipto Roy , Surajit Chattopadhyay , Antonio Pasqua

A cosmological model has been constructed in the framework of Brans-Dicke (BD) gravity, based on an inter-conversion between matter and dark energy, for a spatially flat universe in the era of pressureless dust. To account for the…

General Relativity and Quantum Cosmology · Physics 2020-05-01 Sudipto Roy

We have studied a superbounce scenario in a set up of Brans-Dicke (BD) theory. The BD parameter is considered to be time dependent and is assumed to evolve with the Brans-Dicke scalar field. In the superbounce scenario, the model bounces at…

General Relativity and Quantum Cosmology · Physics 2023-03-28 S. K. Tripathy , S. K. Pradhan , B. Barik , Z. Naik , B. Mishra

A conformal transformation of a static or stationary spacetime by a time dependent conformal scale factor ${S(\tau )}^2$ is one of the methods of producing a cosmological spacetime. Using this knowledge and Brans-Dicke (BD) field equations,…

General Relativity and Quantum Cosmology · Physics 2023-12-07 Dilek K. Çiftci , Ali Demirözlü

Based on the idea that the components of a cosmological metric may be determined by the total gravitational potential of the universe, the scalar field $\phi=1/G$ in the Jordan-Brans-Dicke (JBD) theory is introduced as evolving with the…

General Relativity and Quantum Cosmology · Physics 2023-05-18 Onder Dunya , Metin Arik

A linear relationship between the Hubble expansion parameter and the time derivative of the scalar field is explored in order to derive exact cosmological, attractor-like solutions, both in Einstein's theory and in Brans-Dicke gravity with…

General Relativity and Quantum Cosmology · Physics 2010-10-27 Olga Arias , Tame Gonzalez , Yoelsy Leyva , Israel Quiros

In this paper, the cosmological dynamics of Brans-Dicke theory in which there are fermions with a coupling to BD scalar field as well as a self-interaction potential is investigated. The conditions that there exists a solution which is…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-21 Dao-Jun Liu

The Brans-Dicke (BD) theory of gravity is taken as a possible theory of k-essence coupled to gravity. It then has been realized that the BD scalar field does indeed play a role of a k-essence, but in a very unique way which distinguishes it…

Astrophysics · Physics 2007-05-23 Hongsu Kim

This paper is devoted to study the accelerated expansion of the universe by exploring the Brans-Dicke parameter in different eras. For this purpose, we take FRW universe model with viscous fluid (without potential) and Bianchi type I…

General Relativity and Quantum Cosmology · Physics 2015-06-15 M. Sharif , Saira Waheed

Consequences of the consistent exact solution of Einstein-Cartan equation on the time dependence of Hubble parameter are discussed. The torsion leads to a space and time dependent expansion parameter which results into nontrivial windows of…

General Relativity and Quantum Cosmology · Physics 2024-02-08 K. Morawetz

We investigate the most general exact solutions of Brans-Dicke cosmology by choosing the scale factor "a" as the new independent variable. It is shown that a set of three field equations can be reduced to a constraint equation and a first…

General Relativity and Quantum Cosmology · Physics 2023-02-15 Medine Ildes , Metin Arik

We report strong cosmological constraints on the Brans-Dicke (BD) theory of gravity using Cosmic Microwave Background data from Planck.We consider two types of models. First, the initial condition of the scalar field is fixed to give the…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-09 A. Avilez , C. Skordis

Spherically symmetric time-dependent solutions for the 5D system of a scalar field canonically coupled to gravity are obtained and identified as an extension of recent results obtained by Ahmed, Grzadkowskia and Wudkab. The corresponding…

General Relativity and Quantum Cosmology · Physics 2014-12-31 Alex E. Bernardini , R. T. Cavalcanti , Roldao da Rocha

Brans-Dicke (BD), one of the first proposed scalar-tensor theories of gravity, effectively makes the gravitational constant of general relativity (GR) time-dependent. Constraints on the BD parameter $\omega$ serve as a benchmark for testing…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-04 Herman Sletmoen , Hans A. Winther
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