A class of homogeneous cosmological models
Abstract
Einstein's field equations are studied under the assumptions that (1) the source of the gravitational field is a perfect fluid, and (2) there exists a group of motions simply transitive on threesurfaces orthogonal to the fluid flow vector. There are two classes of solutions; these are studied in detail. Three special families of solutions examined include all analytic solutions of the field equations obeying (1) and (2) of which the authors are aware. The relation of these solutions to various vacuum solutions is indicated.
 Publication:

Communications in Mathematical Physics
 Pub Date:
 June 1969
 DOI:
 10.1007/BF01645908
 Bibcode:
 1969CMaPh..12..108E