Parallel universe (fiction)

Parallel universe or alternative reality is a self-contained separate reality coexisting with our own. A specific group of parallel universes is called a multiverse, although this term can also be used to describe the possible parallel universes that comprise physical reality. While the terms "parallel universe" and "alternative reality" are generally synonymous and can be used interchangeably in most cases, there is sometimes an additional connotation implied with the term "alternative reality" that implies that the reality is a variant of our own. The term "parallel universe" is more general, without any connotations implying a relationship (or lack thereof) with our own universe.

Introduction :

Fantasy has long borrowed the idea of "another world" from myth, legend and religion. Heaven, Hell, Olympus, Valhalla are all alternative universes different from the familiar material realm. Modern fantasy often presents the concept as a series of planes of existence where the laws of nature differ, allowing magical phenomena of some sort on some planes. This concept was also found in ancient Hindu mythology, in texts such as the Puranas, which expressed an infinite number of universes, each with its own gods.Carl Sagan, Placido P D'Souza (1980s). Hindu cosmology's time-scale for the universe is in consonance with modern science.; Dick Teresi (2002). Lost Discoveries : The Ancient Roots of Modern Science - from the Babylonians to the Maya. In other cases, in both fantasy and science fiction, a parallel universe is a single other material reality, and its co-existence with ours is a rationale to bring a protagonist from the author's reality into the fantasy's reality, such as in The Chronicles of Narnia by C.S. Lewis or even the beyond-the-reflection travel in the two main works of Lewis Carroll. Or this single other reality can invade our own, as when Margaret Cavendish's English heroine sends submarines and "birdmen" armed with "fire stones" back through the portal from the Blazing World to Earth and wreaks havoc on England's enemies. In dark fantasy or horror the parallel world is often a hiding place for unpleasant things, and often the protagonist is forced to confront effects of this other world leaking into his own, as in most of the work of H. P. Lovecraft and the Doom computer game series. In such stories, the nature of this other reality is often left mysterious, known only by its effect on our own world.
 
Often the alternative worlds theme in science fiction is framed by postulating that every historical event spawns a new universe for every possible outcome, resulting in a number of alternate histories. This literary interpretation is sometimes rooted in the many-worlds interpretation of quantum mechanics formulated by the physicist Hugh Everett in 1957, an alternative to the Copenhagen interpretation originally formulated by Niels Bohr and Werner Heisenberg around 1927. (See: multiverse.) This kind of alternative universe is often the backdrop of stories involving time travel and is often used to rationalize the logical paradoxes that arise when an author allows characters to travel backward in time. (See: grandfather paradox.) The concept also arises outside the framework of quantum mechanics, as is found in Jorge Luis Borges short story El jardín de senderos que se bifurcan ("The Garden of Forking Paths"), published in 1941 before the many-worlds interpretation had been invented. In the story, a Sinologist discovers a manuscript by a Chinese writer where the same tale is recounted in several ways, often contradictory, and then explains to his visitor (the writer's grandson) that his relative conceived time as a "garden of forking paths", where things happen in parallel in infinitely branching ways. While this is a common treatment in SF, it is by no means the only presentation of the idea, even in hard science fiction. Sometimes the parallel universe bears no historical relationship to any other world; as in the novel Raft by Stephen Baxter, which posits a reality where the gravitational constant is much larger than in our universe. (Note, however, that Baxter explains later in Vacuum Diagrams that the protagonists in Raft are descended from people who came from the Xeelee Sequence universe.)
 
One motif is that the time flow in a parallel universe may be very different, so that a character returning to one might find the time passed very differently for those he left behind. This is found in folklore: King Herla visited Fairy and returned three centuries later; although only some of his men crumbled to dust on dismounting, Herla and his men who did not dismount were trapped on horseback, this being one folkloric account of the origin of the Wild Hunt.Briggs (1967) p.50-1 C.S. Lewis made use of this in the Chronicles of Narnia; indeed, a character points out to two skeptics that there is no need for the time between the worlds to match up, but it would be very odd for the girl who claims to have visited a parallel universe to have dreamed up such a different time flow.Gareth Matthews, "Plato in Narnia" p 171 Gregory Bassham ed. and Jerry L. Walls, ed. The Chronicles of Narnia and Philosophy ISBN 0-8126-9588-7
 
It should be noted that the division between science fiction and fantasy becomes fuzzier than usual when dealing with stories that explicitly leave the universe we are familiar with, especially when our familiar universe is portrayed as a subset of a multiverse. Picking a genre becomes less a matter of setting, and more a matter of theme and emphasis; the parts of the story the author wishes to explain and how they are explained. Narnia is clearly a fantasy, and the TV series Sliders is clearly science fiction, but works like the World of Tiers series tend to occupy a much broader middle ground.

Uses in science fiction :

Other dimensions :

While technically incorrect, and looked down upon by hard science-fiction fans and authors, the idea of another dimension has become synonymous with the term parallel universe. The usage is particularly common in movies, television and comic books and much less so in modern prose science fiction.
 
In written science fiction, new dimensions more commonly and more accurately refer to additional coordinate axes, beyond the three spatial axes with which we are familiar. By proposing travel along these extra axes, which are not normally perceptible, the traveler can reach worlds that are otherwise unreachable and invisible. One of the first works of modern science fiction, The Time Machine by H. G. Wells used time as an additional dimension in this sense, taking the four-dimensional model of classical physics and interpreting time as a spatial dimension in which humans could travel with the right equipment.
 
There are many examples where authors have explicitly created additional spatial dimensions for their characters to travel in, to reach parallel universes. Douglas Adams, in the last book of the Hitchhiker's Guide to the Galaxy series, Mostly Harmless, uses the idea of probability as an extra axis in addition to the classical four dimensions of space and time. Though, according to the novel, they're not really parallel universes at all but only a model to capture the continuity of space, time and probability. Robert A. Heinlein, in The Number of the Beast, postulated a six-dimensional universe. In addition to the three spatial dimensions, he invoked symmetry to add two new temporal dimensions, so there would be two sets of three. Like the fourth dimension of H. G. Wells "Time Traveller", these extra dimensions can be traveled by persons using the right equipment.

Hyperspace :

Perhaps the most common use of the concept of a parallel universe in science fiction is the concept of hyperspace. Used in science fiction, the concept of hyperspace often refers to a parallel universe that can be used as a faster-than-light shortcut for interstellar travel. Rationales for this form of hyperspace vary from work to work, but the two common elements are:

1. at least some (if not all) locations in the hyperspace universe map to locations in our universe, providing the "entry" and "exit" points for travelers.
2. the travel time between two points in the hyperspace universe is much shorter than the time to travel to the analogous points in our universe. This can be because of a different speed of light, different speed at which time passes, or the analogous points in the hyperspace universe are just much closer to each other.

 
Sometimes "hyperspace" is used to refer to the concept of additional coordinate axes. In this model, the universe is thought to be "crumpled" in some higher spatial dimension and that traveling in this higher spatial dimension, a ship can move vast distances in the common spatial dimensions. An analogy is to crumple a newspaper into a ball and stick a needle straight through, the needle will make widely spaced holes in the two-dimensional surface of the paper. While this idea invokes a "new dimension", it is not an example of a parallel universe. It is a more scientifically plausible use of hyperspace. (See wormhole.)
 
While use of hyperspace is common, it is mostly used as a plot device and thus of secondary importance. While a parallel universe may be invoked by the concept, the nature of the universe is not often explored. So, while stories involving hyperspace might be the most common use of the parallel universe concept in fiction, it is not the most common source of fiction about parallel universes.

Time travel and alternate history :

The most common use of parallel universes in science fiction, when the concept is central to the story, is as a backdrop and/or consequence of time travel. A seminal example of this idea is in Fritz Leibers novel, The Big Time where theres a war across time between two alternate futures each side manipulating history to create a timeline that results into their own world. Time-travelers in fiction often accidentally or deliberately create alternate histories, such as in The Guns of the South by Harry Turtledove where the Confederate Army is given the technology to produce AK-47 rifles and ends up winning the American Civil War. (However, Ward Moore reversed this staple of alternate history fiction in his Bring the Jubilee (1953), where an alternative world where the Confederate States of America won the battle of Gettysburg and the American Civil War is destroyed after an historian and time traveller from the defeated United States of that world travels back to the scene of the battle and inadvertently changes the result so that the North wins that battle.) The alternate history novel 1632 by Eric Flint explicitly states, albeit briefly in a prologue, that the time travelers in the novel (an entire town from West Virginia) have created a new and separate universe when they're transported into the midst of the Thirty Years War in 17th century Germany. (This sort of thing is known as an ISOT among alternate history fans, after S.M. Stirling's Island in the Sea of Time: an ISOT is when territory or a large group of people is transported back in time to another historical period or place. http://www.google.com/search?hl=en&safe=off&client=firefox-a&rls=org.mozilla%3Aen-US%3Aofficial&hs=cva&q=ISOT+alternative+history&btnG=Search)
 
The concept of "sidewise" time travel, a term taken from Murray Leinster's "Sidewise in Time," is often used to allow characters to pass through many different alternate histories, all descendant from some common branch point. Often worlds that are similar to each other are considered closer to each other in terms of this sidewise travel. For example, a universe where World War II ended differently would be closer to us than one where Imperial China colonized the New World in the 15th century. H. Beam Piper used this concept, naming it "paratime" and writing a series of stories involving the Paratime Police who regulated travel between these alternative realities as well as the technology to do so. Keith Laumer used the same concept of "sideways" time travel in his 1962 novel Worlds of the Imperium. More recently, Frederik Pohl used the idea in his novel The Coming of the Quantum Cats which is explicitly based on upon a human-scale reading of the "many worlds" interpretation of quantum mechanics, postulating that every historical event spawns a new universe for every possible outcome.
 
It can be argued that most modern alternate histories implicitly refer to parallel universes, based on the above reading of quantum theory. However, many of these works are presented as self-contained worlds in and of themselves, and can be read without resort to additional universes being present. For example, outside The Guns of the South, the large part of Turtledoves work in alternate history makes no reference to any other universes other than the ones in which the stories take place. And Philip K. Dick's classic novel The Man in the High Castle features a universe in which the Axis won World War II, and the only other universe "present" is fictional, in a book whose author imagines an alternative world (different from our own) in which the Allies won. Such stories bear the same relationship to the reader's world as any fantasy (such as J. R. R. Tolkien's The Lord of the Rings novel) that contradicts the reader's reality. By extension all of fiction in general could, by this reasoning, be occurring in a subcreated "alternative reality."John H. Timmerman. "Tolkiens Crucible of Faith: The Sub-Creation". First published June 5, 1974, retrieved October 31, 2006. While this definition might be useful in some critical contexts a more generally useful definition restricts the term to fiction where there are alternative realities presented in the work itself.

Uses in fantasy :

Stranger in a strange land :

Fantasy authors often want to bring characters from the author's (and the reader's) reality into their created world. Before the mid-20th century, this was most often done by hiding fantastic worlds within hidden parts of the author's own universe. Peasants who seldom if ever traveled far from their villages could not conclusively say that it was impossible that an ogre or other fantastical beings could live an hour away, but increasing geographical knowledge meant that such locations had to be farther and farther off.C. S. Lewis, "On Science Fiction", Of Other Worlds, p68 ISBN 0-15-667897-7 Characters in the author's world could board a ship and find themselves on a fantastic island, as Jonathan Swift does in Gulliver's Travels or in the 1949 novel Silverlock by John Myers Myers, or be sucked up into a tornado and land in Oz. These "lost world" stories can be seen as geographic equivalents of a "parallel universe", as the worlds portrayed are separate from our own, and hidden to everyone except those who take the difficult journey there. The geographic "lost world" can blur into a more explicit "parallel universe" when the fantasy realm overlaps a section of the "real" world, but is much larger inside than out, as in Robert Holdstock's novel Mythago Wood.
 
After the mid-20th century, perhaps influenced by ideas from science fiction, perhaps because exploration had made many places on the map too clear to write "Here there be dragons", many fantasy worlds became completely separate from the author's world.C. S. Lewis, "On Science Fiction", Of Other Worlds, p68 ISBN 0-15-667897-7 A common trope is a portal or artifact that connects worlds together, prototypical examples being the wardrobe in C.S. Lewis' The Lion, the Witch, and the Wardrobe, or the sigil in James Branch Cabell's The Cream of the Jest. In Hayao Miyazaki's Spirited Away, Chihiro Ogino and her parents walk through a long tunnel into the spirit world. The main difference between this type of story and the "lost world" above, is that the fantasy realm can only be reached by certain people, or at certain times, or after following certain rituals, or with the proper artifact.
 
In some cases, physical travel is not even possible, and the character in our reality travels in a dream or some other altered state of consciousness. Examples include the Dream Cycle stories by H. P. Lovecraft or the Thomas Covenant stories of Stephen R. Donaldson. Often, stories of this type have as a major theme the nature of reality itself, questioning if the dream-world can have the same "reality" as the waking world. Science fiction often employs this theme (usually without the dream-world being "another" universe) in the ideas of cyberspace and virtual reality.

Between the worlds :

Most stories in this mold simply transport a character from the real world into the fantasy world where the bulk of the action takes place. Whatever gate is used (such as the tollbooth in The Phantom Tollbooth by Norton Juster, or the mirror in Lewis Carroll's Through the Looking Glass) is left behind for the duration of the story, until the end, and then only if the protagonists will return.
 
However, in a few cases the interaction between the worlds is an important element, so that the focus is not on one world or the other, but on both, and their interaction. After Rick Cook introduced a computer programmer into a high fantasy world, his wizardry series steadily acquired more interactions between this world and ours. In Aaron Allston's Doc Sidhe our "grim world" is paralleled by a "fair world" where the elves live and history echoes ours. A major portion of the plot deals with preventing a change in interactions between the worlds. Margaret Ball, in No Earthly Sunne, depicts the interaction of our world with Faerie, and the efforts of the Queen of Faerie to deal with the slow drifting apart of Earth and Faerie. Poul Anderson depicts Hell as a parallel universe in Operation Chaos, and the need to transfer equivalent amounts of mass between the worlds explains why a changeling is left for a kidnapped child.
 
Multiple worlds, rather than a pair, increase the importance of the relationships. In The Lion, the Witch, and the Wardrobe, there are only our world and Narnia, but in other of C. S. Lewis's works, there are hints of other worlds, and in The Magician's Nephew, the Wood between the Worlds shows many possibilities, and the plot is governed by transportation between worlds, and the effort to right problems stemming from them. In Andre Norton's Witch World, begun with a man from Earth being transported to this world, gates frequently lead to other worlds — or come from them. While an abundance of illusions, disguises, and magic that repells attention make certain parts of Witch World look like parallel worlds, some are clearly parallel in that time runs differently in them, and such gates pose a repeated problem in Witch World.

Fantasy multiverses :

The idea of a multiverse is as fertile a subject for fantasy as it is for science fiction, allowing for epic settings and godlike protagonists. Among the most epic and far-ranging fantasy "multiverses" is that of Michael Moorcock. Like many authors after him, Moorcock was inspired by the many worlds interpretation of quantum mechanics, saying:

It was an idea in the air, as most of these are, and I would have come across a reference to it in New Scientist (one of my best friends was then editor) ... or physicist friends would have been talking about it. ... Sometimes what happens is that you are imagining these things in the context of fiction while the physicists and mathematicians are imagining them in terms of science. I suspect it is the romantic imagination working, as it often does, perfectly efficiently in both the arts and the sciences.

Unlike many science-fiction interpretations, Moorcock's Eternal Champion stories go far beyond alternate history to include mythic and sword and sorcery settings as well as some worlds more similar to our own. However, the Eternal Champion himself is incarnate in all of them.
 
Roger Zelazny used a mythic cosmology in his Chronicles of Amber series. His protagonist is a member of the royal family of Amber, whose members represent a godlike pantheon ruling over a prototypical universe that represents Order. All other universes are increasingly distorted "shadows" of it, ending finally at the other extreme, Chaos, which is the complete negation of the prototype. Travel between these "shadow" universes is only possible by beings descended from the blood of this pantheon. Those "of the blood" can walk through Shadow, imagining any possible reality and then walk to it, making their environment more similar to their desire as they go. It is argued between the characters whether these "shadows" even exist before they're imagined by a member of the royal family of Amber, or if the "shadows'" existence can be seen as an act of godlike creation.
 
In the World of Tiers novels by Philip José Farmer, the idea of godlike protagonists is even more explicit. The background of the stories is a multiverse where godlike beings have created a number of pocket universes that represent their own desires. Our own world is part of this series, but interestingly our own universe is revealed to be much smaller than it appears, ending at the edge of the solar system.
 
But even works that deal with lesser beings, the structure of the multiverse may be significiant. Piers Anthony depicts two worlds in the Apprentice Adept series, the SF Proton and the fantasy Phaze, such that every person born in either world has a physical duplicate on the other world. Only when one duplicate has died can the other cross between the worlds.
 
There are multiverses also in Warcraft universe and in The Chronicles of Narnia.

Fictional universe as alternative universe :

There are many examples of the meta-fictional idea of having the author's created universe (or any author's universe) rise to the same level of "reality" as the universe we're familiar with. The theme is present in works as diverse as Myers' Silverlock and Heinleins Number of the Beast. Fletcher Pratt and L. Sprague de Camp took the character Harold Shea in the Incompleat Enchanter series through the worlds of Norse myth, Edmund Spenser's Faerie Queene, Ludovico Ariosto's Orlando Furioso, and the KalevalaMichael Moorcock, Wizardry & Wild Romance: A Study of Epic Fantasy p 88 ISBN 1-932265-07-4— without ever quite settling whether writers created these parallel worlds by writing these works, or received impressions from the worlds and wrote them down. In an interlude set in "Xanadu", a character claims that the universe is dangerous because the poem went unfinished, but whether this was his misapprehension or not is not established.
 
Some fictional approaches definitively establish the independence of the parallel world, sometimes by having the world differ from the book's account; other approaches have works of fiction create and affect the parallel world: L. Sprague de Camp's Solomon's Stone, taking place on an astral plane, is populated by the daydreams of mundane people, and in Rebecca Lickiss's Eccentric Circles, an elf is grateful to Tolkien for transforming elves from dainty little creatures. These stories often place the author, or authors in general, in the same position as Zelazny's characters in Amber. Questioning, in a literal fashion, if writing is an act of creating a new world, or an act of discovery of a pre-existing world.
 
Occasionally, this approach becomes self-referential, treating the literary universe of the work itself as explicitly parallel to the universe where the work was created. Stephen King's seven-volume Dark Tower series hinges upon the existence of multiple parallel worlds, many of which are King's own literary creations. Ultimately the characters become aware that they are only "real" in King's literary universe, and even travel to a world — twice — in which (again, within the novel) they meet Stephen King and alter events in the real Stephen King's world outside of the books.

Elfland :

Elfland, or Faerie, the otherworldly home not only of elves and fairies but goblins, trolls, and other folkloric creatures, has an ambiguous appearance in folklore.
 
On one hand, the land often appears to be continuous to ordinary land. Thomas the Rhymer might, on being taken by the Queen of Faerie, be taken on a road like one leading to Heaven or Hell: So think beset with thorns and briers?
That is that path of righteousness,
Tho after it but few enquires.
 
And see not ye that braid braid road
That lies across the lily leven?
That is the path of wickedness,
Tho some call it the road to heaven.
 
And see not ye that bonny road,
That winds about the fernie brae?
That is the road to fair Elfland,
Where thou and I this night maun gae.}}
 
However, others have found fairies and elves with greater ease. Sir Orfeo discovered the king who had kidnapped his wife by wandering in wilderness. Others have found them in elf hills near the homes, which digging could violate. They have been found in fairy circles, dancing in apparently ordinary woods, or riding through ordinary lands.
 
While sometimes folklore seems to show fairy intrusion into human lands — "Tam Lin" does not show any otherworldly aspects about the land in which the confrontation takes place — at other times the otherworldly aspects are clear. Most frequently, time can flow differently for those trapped by the fairy dance than in the lands they come from; although, in an additional complication, it may only be an appearance, as many returning from Faerie, such as Oisín, have found that time "catches up" with them as soon as they have contact with ordinary lands.
 
Fantasy writers have taken up the ambiguity. Some writers depict the land of the elves as a full-blown parallel universe, with portals the only entry — as in Josepha Sherman's Prince of the Sidhe series or Esther Friesner's Elf Defense — and others have depicted it as the next land over, possibly difficult to reach for magical reasons — Robin McKinley's "The Stolen Princess" in The Door in the Hedge, Hope Mirrlees's Lud-in-the-Mist, or Lord Dunsany's The King of Elfland's Daughter. In some cases, the boundary between Elfland and more ordinary lands is not fixed. Not only the inhabitants but Faerie itself can pour into more mundane regions.
 
This is not a new phenomenon concerning Elfland. In Norse mythology, Elfland (Alfheim) was also the name of what today is the Swedish province of Bohuslän. In the sagas, it said that the people of this petty kingdom were more beautiful than other people, as they were related to the elves, showing that not only the territory was associated with elves, but also the race of its people.

Other media :

Television :

The idea of parallel universes have received treatment in a number of television series, usually as a single story or episode in a more general science fiction or fantasy storyline.
 
The most widely known and imitated example is the original episode entitled Mirror, Mirror. The episode introduced an alternative version of the Star Trek universe where the main characters were barbaric and cruel to the point of being evil. The way Star Trek executed the concept was deeply influential on subsequent treatments. Enough so, that when the parallel universe concept is parodied, it is often this Star Trek episode that's being referenced. Two recent examples are from South Park in the episode Spookyfish where the "evil" universe double of Cartman sports a beard, like the alternative version of Mr. Spock in the Mirror, Mirror episode. In addition, while the "good" universe's Cartman is the most obnoxious character, the "evil" one is pleasant and agreeable. Another animated series, Futurama, had an episode where the cast travels between "Universe A" and "Universe 1" via boxes containing each universe, and one of the major jokes is an extended argument between the two sets of characters over which set were the "evil" ones.
 
One of the earliest television plots to feature parallel time was a 1970 storyline on soap opera Dark Shadows. Vampire Barnabas Collins found a room in Collinwood which served as a portal to parallel time, and he entered the room in order to escape from his current problems. A year later, the show again traveled to parallel time, the setting this time being 1841.
 
Sometimes a television series will use parallel universes as an on-going subplot. This happened as and elaborated on the premise of the original series' "Mirror" universe and developed multi-episode story arcs based on the premise. Other examples are the science fiction series Stargate SG-1, the fantasy/horror series Buffy the Vampire Slayer, Supernatural and the romance/fantasy . Following the precedent set by Star Trek these story arcs show alternative universes that have turned out "worse" than the "original" universe; in Stargate SG-1 the first encountered parallel reality featured Earth being overwhelmed by an unstoppable Goa'uld onslaught, in Buffy, the vampires had overrun Sunnydale and Buffy and Angel were both killed trying to prevent them from massacring the human populace, while in Lois & Clark an alternative universe is visited, repeatedly, that contains a Clark Kent whose parents, Jonathan and Martha Kent died when he was ten years of age, and whose Lois Lane is apparently dead. Clark eventually becames Superman, with help from the 'original' Lois Lane, but he is immediately revealed as Clark Kent and so has no life of his own.
 
In addition to following Star Trek's lead, showing the "evil" variants of the main storyline gives the writers an opportunity to show what is at stake by portraying the worst that could happen and the consequences if the protagonists fail. The latter could also be seen as the point of the alternative reality portrayed in the movie It's a Wonderful Life (see below).
 
There have been relatively few series where parallel universes were central to the series itself. Two examples are the short-lived 1980s series Otherworld which transported a family from our world to an alternative Earth; and Sliders, where the characters travel across a series of "alternative" Earths, trying to get back to their home universe. In 1986, Disney planned to make an animated children's show about interdimensional travel called Fluppy Dogs, but only the pilot episode was ever produced.
 
The third season of the anime Yu-Gi-Oh! GX features multiple dimensions and the main villain plots to bring all of them together and rule them all.
 
Where In Time Is Carmen Sandiego featured a segment with a parallel universe in season 2.
 
Parallel universes are also mentioned in Doctor Who in Series 2, paticulary the episodes The Age of Steel and Rise of the Cybermen, where the TARDIS falls through the time vortex into a parallel universe, which is described by the Doctor as "the same, only a little bit different". The Doctor said that Time Lords has control of parallel universes, and that you could "pop over and be back in time for tea!", but after they were killed in the Time War the "walls of reality closed". It is also mentioned in Army of Ghosts and Doomsday, where Rose Tyler falls into the parallel universe previously visited in The Age of Steel and Rise of the Cybermen, after the "walls close". It is also mentioned when the Doctor is speaking to Captain Jack Harkness about Rose Tyler in the episode Utopia, during Series 3.
 
In the Red Dwarf episode Stasis leak The crew of Red Dwarf travel to a parellel universe where they have female opposites except cat whos opposite is a dog

Movies :

The most famous treatment of the alternative universe concept in film could be considered the The Wizard of Oz, which portrays a parallel world, famously separating the magical realm of the Land of Oz from the mundane world by filming it in Technicolor while filming the scenes set in Kansas in sepia.
 
A later example is the Frank Capra movie, It's a Wonderful Life where the main character George Bailey is shown by a guardian angel the city of Pottersville, which was George Bailey's hometown of Bedford Falls as it would have been if he had never existed. Another notable depiction of a parallel universe in movies is the second film in the Back to the Futuretrilogy (1985, 1989) by Robert Zemeckis, starring Michael J. Fox and Christopher Lloyd, showing an accidentally createdalternative present and future. Like It's a Wonderful Life, The Big Time, and many other time travel stories using this conceit, it is clear that these alternative presents/futures are mutually exclusive with the protagonists' own — so, strictly speaking, the universes aren't parallel in that they cannot co-exist, rather they oscillate between one or the other.
 
Another common use of the theme is as a prison for villains or demons. The idea is used in the first two Superman movies starring Christopher Reeve where Kryptonian villains were sentenced to the Phantom Zone from where they eventually escaped. An almost exactly parallel use of the idea is presented in the campy cult film The Adventures of Buckaroo Banzai Across the 8th Dimension, where the "8th dimension" is essentially a "phantom zone" used to imprison the villainous Red Lectroids. Uses in horror films include the 1986 film From Beyond (based on the H. P. Lovecraftstory of the same name) where a scientific experiment induces the experimenters to perceive aliens from a parallel universe, with bad results. The 1987 John Carpenter film Prince of Darkness is based on the premise that the ChristianSatan is actually an alien being that is the son of something even more evil and powerful, trapped in another universe. The protagonists accidentally free "Satan", who then attempts to release his "father."
 
Some films present parallel realities that are actually different contrasting versions of the narrative itself. Commonly this motif is presented as different points of view revolving around a central (but sometimes unknowable) "truth", the seminal example being Akira Kurosawa's Rashomon. Conversely, often in film noir and crime dramas, the alternative narrative is a fiction created by a central character, intentionally — as in The Usual Suspects — or unintentionally — as in Angel Heart. Less often, the alternative narratives are given equal weight in the story, making them truly alternative universes, such as in the German film Run Lola Run, the short-lived British West End musical Our House and the British film Sliding Doors.
 
Recent films that have more explicitly explored parallel universes are: the 2001 cult movieDonnie Darko, which deals with what it terms a "tangent universe" that erupts from our own universe; Super Mario Bros. (1993) has the eponymous heroes cross over into a parallel universe ruled by humanoids who evolved from dinosaurs; The One (2001) starring Jet Li, in which there is a complex system of realities in which Jet Li's character is a police officer in one universe and a serial killer in another, who travels to other universes to destroy versions of himself, so that he can become 'the one'; and (2004), the main character runs away from a totalitarian nightmare, and he enters into a cyber-afterlife alternative reality And "Dragonball" when future Trunks come from the future.

Comic books :

Parallel universes in modern comics have become particularly rich and complex, in large part due to the continual problem of continuity faced by the major two publishers, Marvel Comics and DC Comics. The two publishers have used the multiverse concept to fix problems arising from integrating characters from other publishers into their own canon, and from having major serial protagonists having continuous histories lasting, as in the case of Superman, over 60 years. Additionally, both publishers have used new alternative universes to re-imagine their own characters. (See Multiverse (DC Comics) and Multiverse (Marvel Comics))
 
Because of this, comic books in general are one of the few entertainment mediums where the concept of parallel universes are a major and ongoing theme. DC in particular periodically revisits the idea in major crossover storylines, such as Crisis on Infinite Earths and Infinite Crisis, where Marvel has a series called What If... that's devoted to exploring alternative realities, which sometime impact the "main" universe's continuity.
 
Recently DC Comics series 52 heralded the return of the Multiverse. 52 was a mega-crossover event tied to Infinite Crisis which was the sequel to the 1980s Crisis on Infinite Earths. The aim was to yet again address many of the problems and confusions brought on by the Multiverse in the DCU. Now 52 Earths exist and including some Elseworld tales such as Kingdom Come, DC's imprintWildstorm Comics and an Earth devoted to the Charlton Comics heroes of DC. Countdown and Countdown Presents: The Search for Ray Palmer and the upcoming Tales of the Multiverse stories expand upon this new Multiverse.
 
Marvel has also had many large crossover events which depicted an alternative universe, each springing from events in the X-Men books, such as Days of Future Past, the seminal Age Of Apocalypse, and 2006's House Of M. In addition the Squadron Supreme is a DC inspired Marvel Universe that has been used several times, often crossing over into the mainstream Universe in the Avengers comic. Exiles is an offshoot of the X-Men franchsie that allows characters to hop from one alternative reality to another, leaving the original, main Marvel Universe intact.
 
Marvel Comics, as of 2000, launched their most popular parallel universe, the Ultimate Universe. It is a smaller subline to the mainstream titles and features Ultimate Spider-Man, Ultimate X-Men, Ultimate Fantastic Four and the Ultimates (their "Avengers"). The line in many ways mimics the new movie franchises in addition to creating younger versions of the modern heroes.

Games :

A small part of EarthBound involves traveling to Moonside, an alternative universe version of the town of Fourside.
 
There is a secret level named "Out of this dimension" in the game Star Fox. The level is somewhat bizarre and confusing, with a slot machine boss waiting in the end.
 
The Dungeons & Dragonsrole-playing game has a thoroughly developed system of planes of existence. A popular campaign setting for the game, Planescape, centers around travelling between these planes. Ravenloft, a gothic horror setting for Dungeons & Dragons, is based entirely in a single demiplane.
 
In the , every plane is part of a multiverse. What effects one plane, may ultimately affect others, such as what happened when a great devastation occurred on the main plane, Dominaria. All the planes around were locked in a bubble, called the Shard, where no one could get in or out. The recent expansion, Planar Chaos, explores the idea of "what if?". The set looks back at the game's history, both mechanically and flavour-wise, and imagines what the game would be like today if certain decisions were made differently. The result is an alternative colour pie - some abilities that are generally only seen in one or two colours in "real Magic" are put in completely different colours. For example, the ability to tap creatures, traditionally white, is put in black. The ideals and philosophies behind the colours remain unchanged - just the abilities that represent them. White is generally a very organized, military-focused colour, and tapping creatures is generally represented as a military tactic of leading an opponent astray (as seen on cards like Master Decoy). In Planar Chaos black, however, it is more seen as either a numbing poison (Midnight Charm), leading a creature into a trap (Rathi Trapper), or flaring negative emotions like immense sadness, resulting in no will to fight (Melancholy).
 
In the computer gameMyst a people known as D'ni colonized Earth from another universe, and kept traveling to other universes (known as Ages) through Linking Books. According to their cosmology, each universe is a leaf of the Terokh Jeruth, the Tree of Possibilities. Myst also includes the use of Trap Books as empty universes for storing criminals, although they were later retconned to be complete universes of their own, called Prison Ages.
 
The Kingdom Hearts series makes frequent use of multiple worlds, implementing Disney properties used as source material as their own world the protagonists can travel to over the course of the game (such as Halloween Town from The Nightmare Before Christmas or Port Royal from ).
 
The Squaresoft game Chrono Cross involves the world being split into two different dimensions, due to an accident involving the fate of a boy named Serge.
 
The 3do series Army Men constantly has its characters jumping from the plastic dimension to ours.
 
In the computer game Red Alert 1, Albert Einstein uses his time machine to go back into past and kill Adolf Hitler in an attempt to prevent World War II. The game takes place in parallel universe where Hitler was eliminated in 1924, and Soviet Union invades Europe in 1940s.
 
In the computer game Red Alert 2, or more specifically, its expansion, Yuri's Revenge, the player must utilise a time machine and travel back in time, to a parallel universe.
 
The Half-Life series strongly features the concept of parallel universes. In the original game, the player visits a 'border world' named Xen. In Half-Life 2, Earth has been taken over by an imperialistic, inter-dimensional alien race known as the Combine.
 
The Silent Hill horror video game series incorporates a concept of parallel worlds that are related to main character's emotions, memories, fears and other projections of his or her subconsciousness. The most common distinction is between the normal world (as the world is seen in reality) and the evil world (as the world is seen when it is devoured by evil powers). Characters are switching (i.e. altering) between these two worlds numerous times during the game's plot. There is a number of ways in which a character may switch between the worlds (for example, he or she may experience a pounding headache and, after this event, he or she "wakes up" in the evil world). The architecture of the evil world (also referred as an alternative world) is basically the same as the one of the normal, "real" world (for instance, a hospital in the normal world has its equivalent in the evil world). However, images of the evil world demonstrate how the real world would look like if it would be devoured by evil powers (for example, a hospital in the real world is no longer a hospital in the evil world - it is in fact a decent torture block full of hellish images of pain and suffering).
 
The massively multiplayer online gameUltima Online used the parallel universe concept to rationalize the existence of multiple instances of the game world (called "shards"), so that players could be partitioned onto multiple servers for capacity reasons.
 
The massively multiplayer online gameCity of Heroes makes extensive use of the parallel universe concept as part of the setting and storyline. The game features a fictional corporation known as Portal Corp, who develop and control technology necessary to "punch" a hole through the dimensional barriers and allow players to travel between worlds, though various groups are also shown to have stolen or copied versions of this technology to allow their own travel on a small scale. The various parallel versions of Earth tend to be depicted as having been overrun by one of the villain groups that exist in the game, or show that history has followed a different path, an example being an Earth were the Allies lost to the Axis forces in World War II. The most prominent version is similar to the concept of the Star Trek original series episode Mirror, Mirror featuring an evil and corrupt version of the Freedom Phalanx. The Rikti in perticular, a key villain group of the game, are presented as trans-dimensional invaders from their own version of Earth.
 
In Bungie's first person shooter Marathon Infinity, the player frequently travels between parallel universes. The game's story involves an ancient alien race known as Jjaro, who have the ability to travel between multiple timelines. They had disappeared from the universe many years prior, presumably because they traveled to one of these timelines. The player is then transported to several alternative universes by the Jjaro to stop the aliens' nemesis, the W'rcacnter, from escaping its prison on a star near the galactic core.
 
Imperator Online is an Alternate Earth MMORPG by Mythic Entertainment, the makers of DAOC, one set in a future world where Ancient Rome never fell. Minor changes at important moments in Roman history create an extremely different timeline for Earth, leading to an interstellar Roman Respublica and thousands of years of galactic Pax Romana. However, the game's production was cancelled in July 2005.

References :

See also :

• List of fiction employing parallel universes
• Multiverse (science)
• Alternate future
• Alternate history
• Alternative universe (fan fiction)
• Fantasy world
• Fictional universe
• Imaginary world
• Pantheistic solipsism
• Murray Leinster Sidewise in Time

External links :

• Max Tegmark's Parallel Universes paper (pdf)