Related papers: Constraining Brans-Dicke Parameter Using Gravitati…
A generalized Brans-Dicke (GBD) theory is proposed and studied in this paper. The interesting property has been found in the GBD theory, for example it can naturally solve the problem of \gamma value emerging in f(R) modified gravity…
Weak field gravitational wave solutions are investigated in Brans-Dicke (BD) theory in the presence of a cosmological constant. In this setting the background geometry is not flat but asymptotically de-Sitter. We investigate the linearised…
In Brans Dicke theory of gravity, from the nature of the scalar field-potential considered, the dark energy, dark matter, radiation densities predicted by different observations and the closedness of the universe considered, we can fix our…
Corrections to general relativity that introduce long-ranged scalar fields which are non-minimally coupled to curvature typically predict that neutron stars possess a non-trivial scalar field profile. An observer far from a star is most…
Observations of gravitational waves from inspiralling compact binaries using laser-interferometric detectors can provide accurate measures of parameters of the source. They can also constrain alternative gravitation theories. We analyse…
The orbital dynamics of fast spinning neutron stars encountering a massive Black Hole (BH) with unbounded orbits are investigated using the quadratic-in-spin Mathisson-Papapetrou- Dixon (MPD) formulation. We consider the motion of the…
In $f(R)$ gravity and Brans-Dicke theory with scalar potentials, we study the structure of neutron stars on a spherically symmetric and static background for two equations of state: SLy and FPS. In massless BD theory, the presence of a…
The gravitational field around an astrophysical black hole (BH) is thought to be described by the Kerr spacetime, which is a solution of the Einstein equation. Signatures of binary black hole (BBH) coalescence in gravitational waves (GW)…
The recently proposed formalism of extended Jordan-Brans-Dicke gravity makes it possible to calculate energy loss rate due to both gravitational wave and scalar field (giving the origin of dark energy) wave emission at merger of a black…
In this paper first we study Brans-Dicke equations with the cosmological constant to find an exact solution in the spatially flat Robertson-Walker metric. Then we use Observational Hubble data, the baryon acoustic oscillation distance ratio…
Based on the new cosmic CMB temperature data from the Planck satellite, the 9 year polarization data from the WMAP, the BAO distance ratio data from the SDSS and 6dF surveys, we place a new constraint on the Brans-Dicke theory. We adopt a…
Neutron stars (NSs) can be used to constrain dark matter (DM) since a NS can transform into a black hole (BH) if it captures sufficient DM particles and exceeds the Chandrasekhar limit. We extend earlier work and for the first time take…
Intermediate/Extreme mass ratio inspiral (I/EMRI) system provides a good tool to test the nature of gravity in strong field. Based on the method of osculating orbits, we compute the orbital evolutions of I/EMRIs on quasi-elliptic orbits in…
In this work we focus on a novel completion of the well-known Brans-Dicke theory that introduces an interaction between the dark energy and dark matter sectors, known as complete Brans-Dicke (CBD) theory. We obtain viable cosmological…
The model of minimal dilatonic gravity (MDG), called also the massive Branse-Dicke model with $\omega =0$, is an alternative model of gravitation, which uses one Branse-Dicke gravitation-dilaton field $\Phi$ and offers a simultaneous…
This paper investigates the orbital dynamics and gravitational wave radiation characteristics of neutral test particles around a static spherically symmetric charged black hole (BH) in 4D Einstein-Gauss-Bonnet (4D-EGB) gravity theory. We…
We analyze the observational constraints on the effective Brans-Dicke parameter and on the temporal variation of the effective gravitational constant within the context of the oscillating G model, a cosmological model based on a massive…
In nonminimally coupled theories where a scalar field is coupled to the Ricci scalar, neutron stars (NSs) can have scalar charges through an interaction with matter mediated by gravity. On the other hand, the same theories do not give rise…
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…
We investigate theoretical and observational constraints on the mass-radius relations for neutron stars. For that purpose we consider the model of neutron stars taking into considerations strong, weak, electromagnetic and gravitational…