Clustering of Galaxies by the Alpha-Effect

Abstract

The development of large-scale flows from the stresses generated by small-scale flows in a Navier-Stokes system is studied in order to model the large-scale structure of the Universe. This process is an analogue of the α-effect, by which a large-scale magnetic field can be generated beginning with small-scale fields. It is shown that, under similar conditions of anisotropy and non-zero mean helicity, large-scale flows can be generated. The clustering of galaxies on all possible scales is then suggested to be a result of the hydrodynamic hierarchy.