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Since the evidence for an accelerated universe and the gap of 70% in the total energy, collected by WMAP, search for alternatives for the general relativity is an important issue, for this theory is not suited for these new phenomena. A particular alternative is the Brans-Dicke theory which has being allowing inspiring results, for example, concerning k-essence type fields in 4 dimensions. However, this theory is almost unexplored in the context of the dimensional reduction of the theory in 3 dimensions. In this work, we address some problems in this dimensional reduction, namely, evaluation of the deceleration parameter of the universe described by the 3 dimensional Brans-Dicke with and without matter. In both cases, we see that it is not possible to consider the theory as a model of k-essence descrybing the dark energy, but it can be considered as descrybing the dark matter.
Intermediate/Extreme mass ratio inspiral (IMRI/EMRI) system provides a good tool to test the nature of gravity in strong field. We construct the self-force and use the self-force method to generate accurate waveform templates for IMRIS/EMRIs on quasi
We investigate a Jordan-Brans-Dicke (JBD) scalar field, $Phi$, with power-law potential in the presence of a second scalar field, $phi$, with an exponential potential, in both the Jordan and the Einstein frames. We present the relation of our model w
In the context of generalised Brans-Dicke cosmology we use the Killing tensors of the minisuperspace in order to determine the unspecified potential of a scalar-tensor gravity theory. Specifically, based on the existence of contact symmetries of the
When Brans-Dicke Theory is formulated in terms of the Jordan scalar field phi, dark energy is related to the mass of this field. We show that if phi is taken to be a complex scalar field then an exact solution of the vacuum equations shows that Fried
The purpose of this study is to investigate observational features of Brans-Dicke wormholes in a case if they exist in our Universe. The energy flux from accretion onto a Brans-Dicke wormhole and the so-called maximum impact parameter are studied (th