This is an invited review paper by a worldclass authority, so it could be useful. http://arxiv.org/abs/0804.2258 Let there be Light: the Emergence of Structure out of the Dark Ages in the Early Universe Abraham Loeb (Harvard) 32 pages, 18 figures, an invited review for the UNESCO EOLSS Encyclopedia (Submitted on 14 Apr 2008) "The initial conditions of our Universe can be summarized on a single sheet of paper. Yet the Universe is full of complex structures today, such as stars, galaxies and groups of galaxies. In this review I describe the standard theoretical model for how complexity emerged from the simple initial state of the Universe at early cosmic times through the action of gravity. In order to test and inform the related theoretical calculations, large-aperture telescopes and arrays of radio antennae are currently being designed and constructed. The actual transition from simplicity to complexity has not been observed as of yet. The simple initial conditions were already traced in maps of the microwave background radiation, but the challenge of detecting the first generation of galaxies defines one of the exciting frontiers in the future of cosmology. Once at hand, the missing images of the infant Universe might potentially surprise us and revise our current ideas."