"Dark matter" was first introduced by Zwicky in 1933 to resolve a discrepancy be tween the dynamical and luminous masses of the Coma cluster. In spite of tremen dous developments in observations and various theoretical attempts, the problem of dark matter has not been resolved but has rather deepened in mystery. Though it is now certain that dark matter constitutes a dominant part of the matter in the universe, its distribution and accurate abundance are not known well. Though many people believe that it consists of non-baryonic matter, no one can reject the bary onic candidate for sure....