Parallel universes in fiction
A parallel universe, also known as an alternate universe, parallel world, parallel dimension, alternate reality, or alternative dimension, is a hypothetical self-contained plane of existence, co-existing with one's own. The sum of all potential parallel universes that constitute reality is often called a "multiverse". While the six terms are generally synonymous and can be used interchangeably in most cases, there is sometimes an additional connotation implied with the term "alternate universe/reality" that implies that the reality is a variant of our own, with some overlap with the similarly named alternate history.
Edwin A. Abbott's Flatland is set in a world of two dimensions.
British author H. G. Wells' 1895 novel The Time Machine, an early example of time travel in modern fiction
Oz and its surroundings
Through the Looking-Glass – and the parallel universe Alice found there
Murray Leinster was a pen name of William Fitzgerald Jenkins, an American writer of genre fiction, particularly of science fiction. He wrote and published more than 1,500 short stories and articles, 14 movie scripts, and hundreds of radio scripts and television plays.
Leinster's "Juju" was the cover story of The Thrill Book in October 1919.
Leinster's "The Fifth-Dimensional Catapult" was the cover story in the January 1931 Astounding Stories.
Leinster's "Planet of Sand" was cover-featured on the February 1948 issue of Famous Fantastic Mysteries.
Leinster's "The Strange Invasion" was the cover story on the April 1958 issue of Satellite Science Fiction. It was issued in book form later that year as War with the Gizmos.
