 Large-scale structure of the universe

The large-scale structure of the universe is the spatial organization of matter into dark matter halos, galaxy clusters, sheets, filaments and cosmic voids. Galaxy clustering traces this pattern, while the underlying matter also includes material that does not shine. Gravity amplifies initial linear cosmological density perturbations, but expansion and the matter's dynamics determine which scales grow efficiently. Comparing observed statistics with models of cosmological structure formation turns this pattern into a test of the initial conditions and subsequent evolution.