Mapeamento de teorias RGBs: o caso da gravidade EiBl com campo escalar.

Abstract

General Relativity has been very well tested since its formulation. However, with the evolution of observations in Cosmology, discrepancies between observations and theoretical calculations arised. These discrepancies are explained by incorporating the so-called dark matter and dark energy. However, these new components have never been effectively measured, apart from their gravitational effects. Seeking alternative routes to avoid or complement the introduction of exotic components, a huge number of modifications and extensions of the laws of gravity have emerged in recent decades. However, new proposals also pose new problems. The metric-affine (or Palatini) formalism is a way of extending GR without introducing new dynamic degrees of freedom, and maintaining second order field equations. In this work we analyze the Eddington-Inspired-Born-Infeld gravity model, described in the Palatini formalism, making use of a powerful tool that allows to build explicit solutions for the RBG class of theories, to which EiBI belongs. The obtained solutions are analyzed and discussed thoroughly.