Título: Modified F(R)-gravity: an alternative to the Dark Energy

Abstract : In the present talk, it is introduced the F(R) theory,
which constitutes an alternative way to explain the current cosmic
acceleration. Since 1998, when the majority of the scientific
community accepted the cosmic acceleration by means of the analysis of
supernova data, a lot of models of dark energy have been suggested.
The modification of the General Relativity avoids the need to
introduce any exotic form of energy that produces a repulsive gravity
interaction, and it gives a natural explanation to the cosmic
acceleration. I will briefly introduce the development of such theory,
and then, some cosmological solutions will be constructed. The aims
and problems of this modification of the General Relativity will be
discussed.