Some implications and consequences of the expansion of the universe are examined. In Chapter 1 it is shown that this expansion creates grave difficulties for the Hoyle-Nardikar theory of gravitation. Chapter 2 deals with perturbations of an expanding homogeneous and isotropous universe. The conclusion is reached that galaxies cannot be formed as a result of the growth of perturbations that were initially small. The propagation and absorption of gravitational radiation is also investigated in this approximation. In chapter 3 gravitational radiation in an expanding universe is examined by a method of asymptotic expansions. The 'peeling-off' behaviour and the asymptotic group are derived. Chapter 4 deals with the occurrence of singularities in cosmological models. It is shown that a generality is inevitable provided that certain very general conditions are satisfied.
Hawking, Stephen W. Properties of Expanding Universes. PhD diss. Cambridge U, 1965. Online facsimile at Apollo. 2017.*