Related papers: A note on Gravitational radiation in generalized B…
Screened modified gravity (SMG) is a kind of scalar-tensor theory with screening mechanisms, which can suppress the fifth force in dense regions and allow theories to evade the solar system and laboratory tests. In this paper, we…
Memory effects are studied in the simplest scalar-tensor theory, the Brans--Dicke (BD) theory. To this end, we introduce, in BD theory, novel Kundt spacetimes (without and with gyratonic terms), which serve as backgrounds for the ensuing…
A gravitating global monopole produces a repulsive grativational field outside the core in addition to a solid angular deficit in the Brans-Dicke theory. As a new feature, the angular deficit is dependent on the values of \phi_{\infty} and…
This research focus on the investigation of relativistic quantum dynamics of spin0 scalar particles/fields through the utilization of the Klein-Gordon (KG) equation within the framework of an electrovacuum space-time in the presence of an…
This talk reviews the constraints imposed by binary-pulsar data on gravity theories, focusing on ``tensor-scalar'' ones which are the best motivated alternatives to general relativity. We recall that binary-pulsar tests are qualitatively…
In the Brans-Dicke(BD) theory on $M_{4}\times Z_{2}$ geometry the geometrical meaning of the torsion is clarified. The BD theory on $M_{4}\times Z_{2}$ is rederived by taking into account of a new isometry condition.
We argue that the geodesic hypothesis based on auto-parallels of the Levi-Civita connection may need refinement in theories of gravity with additional scalar fields. This argument is illustrated with a re-formulation of the Brans-Dicke…
We present calculations of Post-Newtonian parameters for Brans-Dicke tensor-scalar gravity in an arbitrary number of compact extra dimensions in both the Jordan and Einstein conformal frames. We find that the parameter gamma, which measures…
Dynamical Chern-Simons (DCS) gravity, a typical parity-violating gravitational theory, modifies both the generation and propagation of gravitational waves from general relativity (GR). In this work, we derive the gravitational waveform…
We combine new Cosmic Microwave Background (CMB) data from Planck with Baryon Acoustic Oscillation (BAO) data to constrain the Brans-Dicke (BD) theory, in which the gravitational constant $G$ evolves with time. Observations of type Ia…
We investigate the gravitational waves phenomena in the geometric scalar theory of gravity (GSG) that belongs to a class of theories such that gravity is described by a single scalar field. The associated physical metric describing the…
In a subclass of Horndeski theories with the speed of gravity equivalent to that of light, we study gravitational radiation emitted during the inspiral phase of compact binary systems. We compute the waveform of scalar perturbations under a…
It is investigated the gravitational waves phenomena in the geometric scalar theory of gravity (GSG), a class of theories such that gravity is described by a single scalar field. The associated physical metric describing the spacetime is…
We investigate the dynamics of asymmetric binaries in extensions of General Relativity featuring a massless scalar field non-minimally coupled to gravity, focusing on the interplay between eccentricity and inclination in fully generic bound…
The nature of gravitational waves in a generalized gravitation theory is investigated. The linearized field equations and the metric tensor quadrupole moment power and the decrease in radius of an inspiralling binary system of two compact…
We derive the gravitational field and equations of motion of compact binary systems up to the 5/2 post-Newtonian approximation of general relativity (where radiation-reaction effects first appear). The approximate post-Newtonian…
We obtain the equations of motion for compact binary systems (black holes or neutron stars) in an alternative theory of gravity known as Einstein-AEther theory, which supplements the standard spacetime metric with a timelike four-vector…
Amplitude and phase of the gravitational waveform from compact binary systems can be decomposed in terms of their mass- and current-type multipole moments. In a modified theory of gravity, one or more of these multipole moments could…
We calculate the explicit equations of motion for non-spinning compact objects to 2.5 post-Newtonian order, or O(v/c)^5 beyond Newtonian gravity, in a general class of scalar-tensor theories of gravity. We use the formalism of the Direct…
Gravitational observables for binary systems exhibit a simple polynomial dependence on the masses $m_1$, $m_2$ of the two scattering objects when they are written in terms of the appropriate kinematic variables in the post-Minkowskian (PM)…