Isotropy, homogeneity and dipole saturation

Abstract

A distribution of points that satisfies the property of local isotropy is not necessarily homogeneous: homogeneity is implied by the condition of local isotropy together with the assumption of analyticity or regularity. Here we show that the evidence of dipole saturation in galaxies (and clusters) catalogues, together with a monotone growth of the monopole, is an evidence of isotropy but not of homogeneity. This is fully compatible with a fractal structure which has the property of local isotropy, but it is non-analytic and non-homogeneous.