The Fluctuations of the Cosmic Microwave Background for a Compact Hyperbolic Universe

The fluctuations of the cosmic microwave background (CMB) are investigated for a small open universe, i.e., one which is periodically composed of a small fundamental cell. The evolution of initial metric perturbations is computed using the first 749 eigenmodes of the fundamental cell in the framework of linear perturbation theory using a mixture of radiation and matter. The fluctuations of the CMB are investigated for various density parameters Omega_0 taking into account the full Sachs-Wolfe effect. The corresponding angular power spectrum C_l is compared with recent experiments.