Alternate reality

Alternate reality (or Alternative reality, UK English) often refers to parallel universes in fiction, a self-contained separate world, universe or reality coexisting with the real world, which is used as a recurring plot point or setting used in fantasy and science fiction.

Alternate reality may also refer to:

Science

 * The many-worlds interpretation of quantum mechanics, which implies the existence of parallel universes
 * Multiverse, a group of multiple universes

Arts and media

 * Alternate history, a genre of fiction consisting of stories that are set in worlds in which historical events unfold differently from the real world
 * Alternate universe (fan fiction), fiction by fan authors that deliberately alters facts of the canonical universe they are writing about

Literature

 * Alternate Realities (Cherryh), a 2000 anthology of science fiction by C. J. Cherryh

Games and video games

 * Alternate Reality (series), a role-playing video game series started in 1985 with two of several intended games released
 * Alternate reality game, a type of cross-media game
 * Virtual reality, simulated reality

Other uses

 * A euphemism for "psychedelic experience"