Isotropization of two-component fluids

We consider the problem of late-time isotropization in spatially homogeneou s but anisotropic cosmological models when the source of the gravitational field consists of two noninteracting perfect fluids-one tilted and one nont ilted. In particular, we study irrotational Bianchi type V models. By intro ducing appropriate dimensionless variables, a full global understanding of the state space of the gravitational field equations becomes possible. The issue of isotropization can then be addressed in a simple fashion. We also discuss implications for the cosmic "no-hair" theorem for Bianchi models wh en part of the source is a tilted fluid. (C) 2000 American Institute of Phy sics. [S0022-2488(00)02110-1].