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Non-minimally coupled curvature-matter gravity models are an interesting alternative to the Theory of General Relativity and to address the dark energy and dark matter cosmological problems. These models have complex field equations that prevent a full analytical study. Nonetheless, in a particular limit, the behavior of a matter distribution can, in these models, be described by a Schrodinger-Newton system. In nonlinear optics, the Schrodinger-Newton system can be used to tackle a wide variety of relevant situations and several numerical tools have been developed for this purpose. Interestingly, these methods can be adapted to study General Relativity problems as well as its extensions. In this work, we report the use of these numerical tools to study a particular non-minimal coupling model that introduces two new potentials, an attractive Yukawa potential and a repulsive potential proportional to the energy density. Using the imaginary-time propagation method we have shown that stationary solutions arise even at low energy density regimes.
The extended scalar-tensor and vector-tensor theories admit black hole solutions with the nontrivial profiles of the scalar and vector fields, respectively. The disformal transformation maps a solution in a class of the scalar-tensor or vector-tensor
We review analytical solutions of the Einstein equations which are expressed in terms of elementary functions and describe Friedmann-Lema^itre-Robertson-Walker universes sourced by multiple (real or effective) perfect fluids with constant equations o
We investigate perturbations of a class of spherically symmetric solutions in massive gravity and bi-gravity. The background equations of motion for the particular class of solutions we are interested in reduce to a set of the Einstein equations with
[Abridged] If gravitation is to be described by a hybrid metric-Palatini $f(mathcal{R})$ gravity theory there are a number of issues that ought to be examined in its context, including the question as to whether its equations allow homogeneous Godel-
We present a detailed study of the static spherically symmetric solutions in de Rham-Gabadadze-Tolley (dRGT) theory. Since the diffeomorphism invariance can be restored by introducing the St{u}ckelberg fields $phi^a$, there is new invariant $I^{ab}=g