In science fiction, a fictional universe may be a remote alien planet or galaxy with little apparent relationship to the real world (as in Star Wars); in fantasy it may be a greatly fictionalized or invented version of Earth's distant past or future (as in The Lord of the Rings).[1]
Fictional continuity
In a 1970 article in CAPA-alpha, comics historian Don Markstein provided a definition of fictional universe meant to clarify the concept of fictional continuities. According to the criteria he imagined:[3]
If characters A and B have met, then they are in the same universe; if characters B and C have met, then, transitively, A and C are in the same universe.
Characters cannot be connected by real people—otherwise, it could be argued that Superman and the Fantastic Four were in the same universe, as Superman met John F. Kennedy, Kennedy met Neil Armstrong, and Armstrong met the Fantastic Four.
Characters cannot be connected by characters "that do not originate with the publisher"—otherwise it could be argued that Superman and the Fantastic Four were in the same universe, as both met Hercules.
Characters are only considered to have met if they appeared together in a story; therefore, characters who simply appeared on the same front cover are not necessarily in the same universe.
Collaboration
Fictional universes are sometimes shared by multiple prose authors, with each author's works in that universe being granted approximately equal canonical status. For example, Larry Niven's fictional universe Known Space has an approximately 135-year period in which Niven allows other authors to write stories about the Man-Kzin Wars. Other fictional universes, like the Ring of Fire series, actively court canonical stimulus from fans, but gate and control the changes through a formalized process and the final say of the editor and universe creator.[4]
^ a bSchult, Stefanie; Tolkien, J. R. R.; Pratchett, Terry; Williams, Tad (2017). Subcreation: fictional-world construction from J.R.R. Tolkien to Terry Pratchett and Tad Williams. Ernst-Moritz-Arndt-Universität Greifswald. Berlin: Logos Verlag Berlin GmbH. ISBN 978-3-8325-4419-5.
^Pavel, Thomas G. (1986). Fictional Worlds. Harvard University Press. ISBN 9780674299665.
^"THE MERCHANT OF VENICE meets THE SHIEK OF ARABI", by Don Markstein (as "Om Markstein Sklom Stu"), in CAPA-alpha #71 (September 1970); archived at Toonopedia
Diana Wynne Jones: The Tough Guide to Fantasyland, New York : Firebird, 2006. ISBN 0-14-240722-4, Explains and parodies the common features of a standard fantasy world