Newtonian universes expanding or contracting with shear and rotation

Abstract

Newtonian cosmology is examined fundamentally and an approach initiated by J. V. Narlikar (1963) is pursued in considerable detail. Homogeneous models expanding with spin and shear are shown unequivocally to possess a singularity. Nevertheless in the presence of sufficient spin they can pass through a well-behaved density maximum at some other epoch. Discrepancies between the conclusions of Narlikar and those of Heckmann & Shucking (1955, 1956) are cleared up. Representative solutions, including models tentatively matched to the actual universe are illustrated.