“The way in which the universe expands is determined by the variation of this [radius of curvature] R with the time. There are three types, or families, of non-static universes… the oscillating universes, and the expanding universes of the first and of the second kind. …each of these is a representative of a family, comprising an infinite number of members differing in size and shape. …In the expanding family of the first kind the radius is continually increasing from… zero… In the expanding series of the second type the radius has at the initial time a certain minimum value, different for the different members of the family. [Both kinds of expanding families] become infinite after an infinite time.”

— Willem de Sitter

Kosmos (1932)

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Willem de Sitter 44

Dutch cosmologist 1872–1934

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We walk the stage of life, performers of a drama for the benefit of the cosmic spectator. As the scenes proceed he notices that the actors are growing smaller and the action quicker. When the last act opens the curtain rises on midget actors rushing through their parts at frantic speed. Smaller and smaller. Faster and faster. One last microscopic blurr of intense agitation. And then nothing.

pp. 90–92 https://books.google.co.uk/books?id=KHyV4-2EyrUC&pg=PA90
The Expanding Universe (1933)