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Related papers: The complete Brans-Dicke theories

200 papers

Generalized ideas of unified dark matter and dark energy in the context of dynamical space time theories with a diffusive transfer of energy are studied. The dynamical space-time theories are introduced a vector field whose equation of…

General Relativity and Quantum Cosmology · Physics 2019-06-26 David Benisty , Eduardo Guendelman , Zbigniew Haba

In the context of scalar-tensor theories we study the evolution of the density contrast for Jordan-Fierz-Brans-Dicke theories in a Friedmann-Lemaitre-Robertson-Walker Universe. Calculations are performed in the Einstein Frame with the…

General Relativity and Quantum Cosmology · Physics 2013-12-16 J. A. R. Cembranos , A. de la Cruz Dombriz , L. Olano Garcia

A quintessence scalar field in self-interacting Brans-Dicke theory is shown to give rise to a non-decelerated expansion of the present universe for open, flat and closed models. Along with providing a non-decelerating solution, it can…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Subenoy Chakraborty , N. C. Chakraborty , Ujjal Debnath

Einstein's field equations with variable gravitational and cosmological ``constant'' are considered in presence of perfect fluid for Bianchi type-I spacetime. Consequences of the four cases of the phenomenological decay of $\Lambda$ have…

General Relativity and Quantum Cosmology · Physics 2008-11-26 J. P. Singh , A. Pradhan , A. K. Singh

In our previous papers we have analyzed the stability of vacuum and electrovacuum static, spherically symmetric space-times in the framework of the Bergmann-Wagoner-Nordtvedt class of scalar-tensor theories (STT) of gravity. In the present…

General Relativity and Quantum Cosmology · Physics 2025-07-24 Kirill A. Bronnikov , Sergei V. Bolokhov , Milena V. Skvortsova , Rustam Ibadov , Feruza Y. Shaymanova

The hypothesis of a discrete fabric of the universe--the "Planck scale"--is always on stage, since it solves mathematical and conceptual problems in the infinitely small. However, it clashes with special relativity, which is designed for…

Quantum Physics · Physics 2016-10-26 Alessandro Bisio , Giacomo Mauro D'Ariano , Paolo Perinotti

In this comment, we have investigated that the power law variation of Brans-Dicke scalar field $(\phi)$ with scale factor $(a)$ is not validated by field equations in general for the Universe filled with dark matter and Tsallis type…

General Physics · Physics 2021-01-12 Anil Kumar Yadav

The Hyperextended Scalar Tensor theory with a potential is defined by three free functions: the gravitational function, the Brans-Dicke coupling function and the potential. Starting from the expression of the 3-volume and the potential as…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Stephane Fay

The field equations in the nonsymmetric gravitational theory are derived from a Lagrangian density using a first-order formalism. Using the general covariance of the Lagrangian density, conservation laws and tensor identities are derived.…

General Relativity and Quantum Cosmology · Physics 2009-10-22 J. Legare , J. W. Moffat

The Lemaitre-Tolman-Bondi solution has received much attention as a possible alternative to Dark Energy, as it is able to account for the apparent acceleration of the Universe without any exotic matter content. However, in order to make…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Chris Clarkson , Timothy Clifton , Sean February

We consider the general behaviour of cosmologies in Brans-Dicke theory where the dilaton is self-interacting via a potential $V(\Phi)$. We show that the general radiation universe is a two-dimensional dynamical system whereas the dust or…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Caroline Santos , Ruth Gregory

Anisotropic spherically symmetric solutions within the framework of the Brans-Dicke theory are uncovered through a unique gravitational decoupling approach involving a minimal geometric transformation. This transformation effectively…

General Relativity and Quantum Cosmology · Physics 2023-11-01 Kazuharu Bamba , M. Z. Bhatti , Z. Yousaf , Z. Shoukat

It is well-known that in four dimensions, black hole solution of the Brans-Dikce-Maxwell equations is just the Reissner-Nordstrom solution with a constant scalar field. However, in $n\geq4$ dimensions, the solution is not yet the…

High Energy Physics - Theory · Physics 2015-05-13 A. Sheykhi , M. M. Yazdanpanah

The purpose of this work is to investigate spatially homogeneous and flat cosmological solutions of the Einstein equations coupled to a non-variational ``near-minimal'' scalar field. This coupling model represents a minimal departure from…

General Relativity and Quantum Cosmology · Physics 2026-05-05 Joshua Ritchie

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

Cosmological solutions of the Brans-Dicke theory with an added cosmological constant are investigated with an emphasis to select a conformal frame in order to implement the scenario of a decaying cosmological constant, featuring an ever…

General Relativity and Quantum Cosmology · Physics 2009-10-30 Yasunori Fujii

In this paper, we explore the nucleation of vacuum bubbles in the Brans-Dicke type theory of gravity. In the Euclidean signature, we evaluate the fields at the vacuum bubbles as solutions of the Euler-Lagrange equations of motion as well as…

High Energy Physics - Theory · Physics 2011-08-08 Hongsu Kim , Bum-Hoon Lee , Wonwoo Lee , Young Jae Lee , Dong-han Yeom

In De Broglie-Bohm Pilot-Wave Theory unique equations of motion and scalar fields for a particle can be formulated. This is done by finding a solution for a divergence free probability density current $\vec{J}(r,t)$ and then dividing by the…

Quantum Physics · Physics 2025-02-06 Connell Bristow

We construct a class of charged rotating solutions in $(n+1)$-dimensional Maxwell-Brans-Dicke theory with flat horizon in the presence of a quadratic potential and investigate their properties. These solutions are neither asymptotically…

High Energy Physics - Theory · Physics 2008-11-26 M. H. Dehghani , J. Pakravan , S. H. Hendi

We consider the Brans-Dicke theory motivated by the $f(R) = R + \alpha R^n - \beta R^{2-n}$ model to obtain a stable minimum of the Einstein frame scalar potential of the Brans-Dicke field. As a result we have obtained an inflationary…

High Energy Physics - Theory · Physics 2014-12-30 Michal Artymowski , Zygmunt Lalak , Marek Lewicki