Oliver F. Piattella

TL;DR: In this article, it was shown that high energy of the order of the Grand Unification scale in the centre of mass of colliding particles can be obtained when there is a multiple collision, where the particle from the accretion disc gets the critical momentum in first collision with the other particle close to the horizon and then there is another collision of the critical particle with the ordinary one.

TL;DR: In this article, it was shown that high energy of the order of the Grand Unification scale in the centre of mass of colliding particles can be obtained when there is a multiple collision -the particle from the accretion disc gets the critical momentum in first collision with the other particle close to the horizon and then there is another collision of the critical particle with the ordinary one.

TL;DR: In this article, the effect of the cosmological expansion on the deflection of light caused by a point mass was analyzed, adopting the McVittie metric as the geometrical description of a point-like lens embedded in an expanding universe.

TL;DR: The k-essence theory with a power-law function and Rastall's non-conservative theory of gravity with a scalar field are shown to have the same solutions for the metric under the assumption that both the metric and the scalar fields depend on a single coordinate as mentioned in this paper.

TL;DR: In this article, the bending of light in a theory of gravity with a Renormalization Group (RG) correction to the gravitational coupling G was evaluated in detail, and the effect of such a correction may be significant to the dynamics of astrophysical systems, and may mimic at least a significant part of the kinematical effects of dark matter in galaxies in great precision.