Robert Scholes

alternate universe n.	1977 R. Scholes & E. S. Rabkin Science Fiction: History, Science, & Vision 178 Science fiction has provided us not only with visions of time travel and hence of alternate time streams, but of whole alternate universes. The term ‘alternate universe’ may refer simply to the universe in which history follows an alternate time stream, but more strictly speaking, it refers to a universe somehow complete and yet coexistent with ours.
timestream n.	1977 R. Scholes & E. S. Rabkin Science Fiction: History, Science, & Vision 178 Science fiction has provided us not only with visions of time travel and hence of alternate time streams, but of whole alternate universes. The term ‘alternate universe’ may refer simply to the universe in which history follows an alternate time stream, but more strictly speaking, it refers to a universe somehow complete and yet coexistent with ours.