Multipole anisotropies of the cosmic background radiation and inflationary models

The effect of stochastic backgrounds of density and gravitational waves (such as those originated by quantum processes in an inflationary stage of the early universe) on the anisotropy of the cosmic background radiation is investigated at large and intermediate angular scales. In particular, Gaussian perturbation spectra whose variance has a power-law shape at horizon crossing are considered. Simple expressions are obtained for the harmonic amplitudes and correlation function of the anisotropy. The experimental data on the dipole and quadrupole harmonics as well as the anisotropies at 2-6 deg are used to constrain parameters of many inflationary cosmologies, namely standard de Sitter, power-law, polelike, and induced gravity-inflation models.