The large-scale structure of the Universe

Research over the past 25 years has led to the view that the rich tapestry of present-day cosmic structure arose during the first instants of creation, where weak ripples were imposed on the otherwise uniform and rapidly expanding primordial soup. Over 14 billion years of evolution, these ripples have been amplified to enormous proportions by gravitational forces, producing ever-growing concentrations of dark matter in which ordinary gases cool, condense and fragment to make galaxies. This process can be faithfully mimicked in large computer simulations, and tested by a variety of observations that probe the history of the Universe starting from just 400,000 yr after the Big Bang.Comment: Invited review to Nature (27 April 2006 issue), Early Universe Supplement, 34 pages, 6 figures (partially size reduced