INHOMOGENEOUS 2-FLUID COSMOLOGIES WITH ELECTROMAGNETIC-FIELD

An algorithm for determining exact solutions of Einstein-Maxwell equations in Ruban's background is presented. In the most general case the cosmological constant is non-zero and the matter content is a mixture of two interacting simple fluids plus a sourceless electromagnetic field. By considering the case of a simple fluid, a class of expanding inhomogeneous solutions generalising the dust model found by Ruban (1982) and the Doroshkevich 'magnetic' universes is derived. The conditions under which the simple fluid may be interpreted as a two-fluid mixture are discussed. The influence of the field near the singularity and at the later stages of the expansion is also examined. A subclass of these models approaches homogeneity and isotropy for large cosmological times.