Dark matter and formation of large-scale structure in the universe - the test by distribution of quasars.

Based on their study of the formation of large scale structure in the universe, the authors expect that: (1) the distribution of quasars should differ from that of galaxies because it has no strong inhomogeneity on the scale of 10 - 100 Mpc; (2) the distributions of quasars with z > 2 and z < 2 should differ from each other. Various analyses on quasar distribution are consistent with these predictions. Particularly, the nearest neighbor test for the complete quasar sample given by Savage and Bolton clearly shows that the distribution of z > 2 quasars is rather homogeneous while the z < 2 quasars have a tendency to clustering.