ON THE ALTERNATIVE ORIGIN OF THE DIPOLE ANISOTROPY OF MICROWAVE BACKGROUND DUE TO THE REES-SCIAMA EFFECT

Recently, Lauer & Postman discovered that the peculiar motion of Local Group with respect to the system defined by Abell clusters and the ma ximum of the dipole anisotropy of cosmic microwave background radiatio n have different directions. The standard interpretation of this pheno menon assumes that there is a bulk stream of Abell clusters themselves caused by a huge unknown mass concentration. However, in principle, i t may occur also that this huge unknown mass concentration does exist, but there is no bulk stream of clusters toward this mass concentratio n, and the intrinsic dipole and other anisotropies of cosmic microwave background radiation are caused via the Rees-Sciama effect due to thi s mass concentration. In this paper, this alternative explanation of t he data of Lauer & Postman is studied. The profile of the redshift of light-that crosses a spherical void and cluster-is calculated analytic ally. Then the obtained formula of this profile is decomposed into the sum of monopole, dipole, quadrupole, etc., terms. It is shown that th e dipole and the quadrupole terms have the same order. Nevertheless, t he observed dipole anisotropy of microwave background radiation is of order similar to 10(-3), but the quadrupole anisotropy, if it exists, is not larger than of order similar to 10(-5). Hence, we obtain the co nclusion that the Rees-Sciama effect hardly can cause a dipole anisotr opy of order similar to 10(-3).