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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

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

We study the transfer of cosmological perturbations through a nonsingular cosmological bounce in a special model in which the parameters of the bounce and the equation of state of matter are chosen such as to allow for an exact calculation…

High Energy Physics - Theory · Physics 2008-07-30 Stephon Alexander , Tirthabir Biswas , Robert H. Brandenberger

In this paper, we investigate the nature of self-interacting potential that can support the accelerated expansion of the universe as indicated by observational data. For this purpose, we consider the Bianchi type I (BI) universe model in…

General Relativity and Quantum Cosmology · Physics 2015-06-12 Muhammad Sharif , Saira Waheed

We study anisotropic inflation in the Brans-Dicke gravity in the presence of an abelian gauge field where the gauge field is non-minimally coupled to the inflaton. We show that the degree of anisotropy, under slow-roll approximations, is…

General Relativity and Quantum Cosmology · Physics 2017-11-03 M. Tirandari , Kh. Saaidi

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

We introduce a designer approach for extended Brans-Dicke gravity that allows us to obtain the evolution of the scalar field by fixing the Hubble parameter to that of a $w$CDM model. We obtain analytical approximations for $\phi$ as a…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-13 Nelson A. Lima , Pedro G. Ferreira

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

We have investigated some bouncing models in the framework of an extended gravity theory where the usual Ricci scalar in the gravitational action is replaced by a sum of the Ricci scalar and a term proportional to the trace of the energy…

General Relativity and Quantum Cosmology · Physics 2019-05-24 Sunil Kumar Tripathy , Rakesh Kumar Khuntia , Priyabrata Parida

This paper is devoted to study Bianchi type I cosmological model in Brans-Dicke theory with self-interacting potential by using perfect, anisotropic and magnetized anisotropic fluids. We assume that the expansion scalar is proportional to…

General Relativity and Quantum Cosmology · Physics 2015-06-04 M. Sharif , Saira Waheed

Within an algebraic framework, used to construct the induced-matter-theory (IMT) setting, in $(D+1)$-dimensional Brans-Dicke (BD) scenario, we obtain a modified BD theory (MBDT) in $D$ dimensions. Being more specific, from the…

General Relativity and Quantum Cosmology · Physics 2014-05-14 S. M. M. Rasouli , Mehrdad Farhoudi , Paulo Vargas Moniz

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

We study the Brans-Dicke model in the presence of an axion. The dynamical equations are solved when the fields are space independent and the metric is spatially flat. It is found that at late time the scale factor undergoes decelerated…

High Energy Physics - Theory · Physics 2009-10-30 Sudipta Mukherji

In this research work, we investigate the late-time accelerated expansion of the universe within the framework of Brans-Dicke theory by considering dynamical vacuum energy models with a time-varying cosmological constant. Two vacuum energy…

General Relativity and Quantum Cosmology · Physics 2026-01-19 Khomesh R. Patle , G. P. Singh , Romanshu Garg

The stability criteria for the generalized Brans-Dicke cosmology in a spatially flat, homogeneous and isotropic cosmological model is discussed in the presence of a perfect fluid. The generalization comes through the channel that the…

General Relativity and Quantum Cosmology · Physics 2017-04-05 Nandan Roy , Narayan Banerjee

We consider a five dimensional DGP-brane scenario endowed with a non-minimally coupled scalar field within the context of Brans-Dicke theory. This theory predicts that the mass appearing in the gravitational potential is modified by the…

General Relativity and Quantum Cosmology · Physics 2009-11-19 K. Atazadeh , H. R. Sepangi

We analyse the fate of density perturbation in the Brans-Dicke Theory, giving a general classification of the solutions of the perturbed equations when the scale factor of the background evolves as a power law. We study with details the…

General Relativity and Quantum Cosmology · Physics 2009-10-28 J. P. Baptista , J. C. Fabris , S. V. B. Goncalves

We consider evolutions of linear fluctuations as the background Friedmann world model goes from contracting to expanding phases through smooth and non-singular bouncing phases. As long as the gravity dominates over the pressure gradient in…

Astrophysics · Physics 2009-11-07 J. Hwang , H. Noh

Massive Brans-Dicke (BD) theory is among the simplest general relativity extensions. It is commonly found as the weak-field limit of other gravitational theories. Here we do a detailed post-Newtonian analysis of massive BD theories. We…

General Relativity and Quantum Cosmology · Physics 2024-02-26 Matheus F. S. Alves , Júnior D. Toniato , Davi C. Rodrigues

Anisotropic dark energy cosmological models are constructed in the frame work of generalised Brans-Dicke theory with a self interacting potential. Wet dark fluid characterized by a linear equation of state is considered as the source of…

General Physics · Physics 2017-05-10 Sunil K. Tripathy , Dipanjali Behera , Bivudutta Mishra