Captive Universe

Harrison, Harry. Captive Universe. New York City: Berkeley Medallion, 1969. For translations, reprints, and reviews, see Internet Speculative Fiction Database, as of October 2023, here.[1]

Generation-starship story featuring two primitive cultures. See below in this Category R. Heinlein's "Universe." Discussed by Casey Fredericks in The Future of Eternity, relevantly here, in the context of two nested "enclosed world"/"spaceship as universe" stories (pp. 18-19).

RDE, initial; finishing 16Oct23