  Recent observation of supernovae type Ia show clearly that there is a large
scale repulsive force in the Universe. Neither of the four known fundamental
interactions can account for this repulsive force. Gravity is known to be the
interaction responsible for the large scale structure and evolution of the
Universe. The problem with gravity is that it gives rise to a force which is
attractive only. Gravity theories, including General Relativity, deals with
gravity as an attractive force. Although this is consistent with our experience
in the solar system and other similar astrophysical systems, gravity theories
fail to account for SN type Ia observation. So, we are in a real problem
concerning the interpretation of these observation. This problem is only ten
years old. In order to go out of this problematic situation, scientists have
suggested the existence of a type of energy in the Universe that is responsible
for the above mentioned repulsive force. They have given this type of energy
the exotic term {\it "Dark Energy"}. Although this type of energy forms more
than two thirds of the energetic contents of our Universe, its reasonable
nature is missing in all gravity theories.
  The aim of the present work is to review the present status of the problem of
dark energy. Also, to suggest a new geometric solution for this problem.
