Cosmic background temperature anisotropy in a minimal isocurvature model for galaxy formation

If the dominant components of the universe were radiation and baryons, and the primeval baryon distribution had a roughly flat spectrum normalized to galaxy clustering on scales of about 20 Mpc, and young stars were able to keep the bulk of the matter ionized at redshifts z greater than about 20, then several encouraging results would follow. The first generation that starts to form when Compton drag becomes unimportant would have masses and radii comparable to galaxies. Mass fluctuations on scales of about 200 Mpc could be relatively large and so perhaps favorable for development of large-scale structure. And the residual fluctuations in the background temperature would have coherence length of about to 3-5 deg and standard deviation of about 0.00001, close to but below the observational bounds. 18 references