Alternate reality


 * This article refers to the general concept of alternate realities, for the timeline of the 2009 movie see alternate reality (Nero, 2233), for other specific timelines see listings below.

An alternate reality (which may also be referred to as an alternate quantum reality, alternate timeline or parallel timeline) is a divergent timeline, a distinct branch in any one universe. The terms "alternate universe" or "parallel universe" are sometimes also used to refer to alternate realities, however such usage is inaccurate; a universe is a distinct separate place, divided from other universes by higher dimensions (and may have its own alternate timelines), while an alternate reality is merely a different quantum facet of any one universe, with the same laws of physics, just different histories. 

As understood by quantum theory, any event creates an infinite number of possible outcomes, all of which are played out in alternate quantum realities. Each alternate reality is ordinarily separate from the others, and distinguished by it's unique quantum signature. Alternate realities, together with alternate universes (and their own alternate realities), form the multiverse. 

Knowledge of other realities
In theory there are an infinite number of realities, ever branching with one for every infinite outcome. As of the 2370s Starfleet had records of 285,000 different quantum realities. 

Other cultures have exhibited far greater knowledge and even control of the timelines; The Sphere Builders had technology which allowed them examine timelines. When they were manipulating the Xindi into trying to destroy Earth in the 22nd century they could see when the actions of the starship Enterprise were generating more timelines with unfavorable outcomes for themselves and acted to try an alter the flow of the events to something they preferred. 

El-Aurians seemed had an innate ability to read timelines; in at least two different alternate timelines, both of which, for different reasons, had seen the Federation and Klingon Empire go to war, Guinan provided counsel to Jean-Luc Picard, concerned that things were not as they should be; she could sense there was another more peaceful timeline and sought to have actions taken to change the timelines to avert the wars. In the 22nd century the Krenim scientist Annorax created the Krenim temporal weapon ship, armed with a weapon which could wipe entire civilizations out of time, and in doing so create new divergent timelines. Over the next two centuries Annorax made alteration after alteration, carefully monitoring the timelines to try and restore the Krenim Imperium to greatness. 

In 2376, Iliana Ghemor, driven mad by years of captivity and believing she was Kira Nerys, devised a plan to travel to as many alternate realities as she could access and kill all other Kira Nerys; determined she would be the only one. 

By the 29th century Starfleet had an advanced knowledge of time travel and alternate realities and employed temporal agents to monitor them. One agent, Captain Braxton became aware of massive event that literally destroyed the galaxy; he could not determine what caused the event due to the temporal chaos surrounding it, but could see that only timeline in which the Federation no longer existed survived it. In trying to undo the catastrophe and save as many timelines as possible Braxton made alterations through time, including attempting to sabotage the Khitomer Accords. 

22nd century alternate timelines
In 2152, Captain Jonathan Archer's removal from history by Daniels created a timeline in which Earth of the 29th century was devastated. (ENT episode: "Shockwave")

In 2153, the Enterprise crossed over into a timeline in which the Daedalus had not been destroyed. (ENT novels: Daedalus and Daedalus's Children)

Later that year, a timeline was created in which Archer was rendered unfit for command, leading to the destruction of Earth by the Xindi and the near extinction of humanity. (ENT episode: "Twilight")

In 2154, a timeline was created in which an attempt by the Enterprise to enter a subspace corridor sent it over a century into the past. (ENT episode: "E²")

Later that year, the Enterprise encountered a timeline in which the Na'kuhl had aided Nazi Germany in World War II. (ENT episodes: "Zero Hour" and "Storm Front")

23rd century alternate timelines
An alternate timeline was created in 2233 when Nero and Spock traveled back in time from 2387. (TOS movie: Star Trek)

In the mid to late 23rd century Christopher Pike commanded a starship Enterprise in a reality in which Earth became isolationist following Terra Prime's successful attack on the Interstellar Coalition conference in 2155. (MyrU novel: A Less Perfect Union)

In 2254, Yeoman J. Mia Colt traveled to an alternate 2293 in which James T. Kirk commanded the Bounty. (EV comic: "Future Tense")

In 2266, a timeline was created in which Kirk died on Grex in 2247. (TOS trilogy: The Janus Gate)

In 2267, Doctor Leonard McCoy traveled through the Guardian of Forever to 1930, creating a timeline in which Edith Keeler did not die in a traffic accident. (TOS episode: "The City on the Edge of Forever" and TOS novel: Provenance of Shadows)

In one timeline, Kirk and Spock failed to prevent McCoy from saving Keeler. (TOS short story: "Triptych")

In another, Keeler was brought to the 23rd century, thus preserving history while allowing her to live. (short story: "Remembering the Future")

Later that year, the Enterprise made first contact with the Mirror Universe. (TOS episode: "Mirror, Mirror")


 * ''See Mirror Universe article for other crossovers with the main Mirror Universe and alternate Mirror Universes.

In 2268, the Enterprise crew made first contact with the X-Men, a group of mutated humans from another timeline. (TOS comic: Star TreX)

Later that year, the Clan Ru created a timeline in which dinosaurs never became extinct and humans never evolved. (TOS novel: First Frontier)

In one timeline, in 2269 Kirk was abducted by Kor, subjected to a Klingon mind sifter, and transported through the Guardian of Forever to 1950s Earth. (TOS short story: "Mind-Sifter")

Also that year, the Romulans implemented their Second History project, briefly creating a timeline in which the Federation never existed. (TOS novel: Killing Time)

Towards the end of the year, a timeline was created in which Spock died on Vulcan as a child. (TAS episode: "Yesteryear")

In 2270, Dr. Georges Mordreaux conducted time travel experiments that resulted in alternate timelines, including one in which his insane future self killed Kirk with a spiderweb gun. (TOS novel: The Entropy Effect)

In 2293, a timeline was created in which Spock was assassinated at Khitomer. (TOS novel: Assignment: Eternity)

24th century alternate timelines
In one timeline, Data was made human by the gods of Elysia in 2365. (TNG novel: Metamorphosis)

In 2366, a timeline was created in which the removal of the Enterprise-C from 2344 resulted in war between the Federation and the Klingons. The Tasha Yar of this timeline joined the crew of the Enterprise-C, and later became the mother of Sela. (TNG episode: "Yesterday's Enterprise")

In one timeline, the Borg invasion of Earth in early 2367 was successful. (TNG short story: "Civil Disobedience")

In 2368, a timeline was created when a Sindareen from 2408 murdered Deanna Troi. (TNG novel: Imzadi)

In 2369, Jean-Luc Picard, with the aid of Q, created a timeline in which he did not get into a fight with a group of Nausicaans in his youth. (TNG episode: "Tapestry")

In 2370, Montgomery Scott traveled back to 2293 and rescued Kirk from his apparent death on the Enterprise-B, thus creating a timeline in which the Borg invasion of 2063 was successful. (TNG novel: Engines of Destiny)

Later that year, Worf encountered many alternate timelines before returning to his own universe. (TNG episode: "Parallels")

Later that year, Trelane created chaos by merging several alternate timelines before being defeated by Picard. (TNG novel: Q-Squared)

Towards the end of the year, Q manipulated Picard into creating an anti-time anomaly that created multiple alternate timelines. (TNG episode: "All Good Things...")

In 2371, members of the crew of Deep Space 9 accidentally created a timeline in which the social reforms that followed the Bell Riots never occurred. (DS9 episode: "Past Tense")

Later that year, the USS Voyager accidentally created a timeline in which a civilization in the Delta Quadrant was destroyed. (VOY episode: "Time and Again")

Shortly afterwards, Voyager made contact with the people of Alcawell, who had the ability to travel to alternate timelines. (VOY novel: The Escape)

Later that year, Miles O'Brien encountered several alternate timelines before dying of radiation sickness and being replaced by his counterpart. (DS9 episode: "Visionary")

Later that year, while Kirk lay dying on Veridian III, the Organians showed him a timeline in which he had resigned from Starfleet following his initial encounter with the Guardian of Forever. (TOS short story: "Reflections")


 * Some have speculated that Kirk's revival through Borg technology and his subsequent adventures in the 24th century occur in an alternate timeline and not the main Star Trek'' timeline.

In 2372, Harry Kim found himself in a timeline in which he had never joined the Voyager crew. (VOY episode: "Non Sequitur")

Later that year, the removal of Benjamin Sisko from normal space-time created an alternate timeline in which Jake Sisko spent the rest of his life trying to get his father back. (DS9 episode: "The Visitor")

In 2373, the Borg created a timeline in which Earth had been assimilated since 2063. (TNG movie: Star Trek: First Contact)

Later that year, a timeline was created in which the USS Defiant traveled back in time 200 years and crashed on a planet in the Gamma Quadrant, forcing the crew to colonize it. (DS9 episode: "Children of Time")

Later that year, Wesley Crusher created a timeline in which the Battle of the Border was fought between the Federation and the Cardassian Union in late 2370. (TNG short story: "Gods, Fate, and Fractals")

In one timeline, Kathryn Janeway and B'Elanna Torres were killed in a Krenim attack this year. (VOY episode: "Before and After")

In one timeline, Captain Braxton believed that Voyager would be responsible for accidentally destroying Earth in the 29th century, and attempted to prevent this by destroying Voyager first. (VOY episode: "Future's End")

In 2374, an alternate timeline was created when Kathryn Janeway and the USS Voyager did not ally with the Borg. (Voy/MyrU novel: Places of Exile)

Later that year, several alternate timelines were created by Krenim officer Annorax's attempts to restore his people's former glory. (VOY episode: "Year of Hell")

That year also saw the creation of a timeline in which the opening of a second wormhole in the Bajoran system destroyed Deep Space 9. (DS9 trilogy: Millennium)

In 2375, an attempt to use a quantum slipstream drive to return Voyager to the Alpha Quadrant created a timeline in which the ship crashed on an ice planet, killing everyone aboard and leaving Chakotay and Harry Kim as the only surviving crewmembers. (VOY episode: "Timeless")

Later that year, a Braxton from an alternate timeline attempted to destroy Voyager again, but was prevented by Seven of Nine. (VOY episode: "Relativity")

In 2376, an alternate timeline was created in which the Borg successfully assimilated Ambassador Spock, leading to the destruction of Starfleet Command and the assimilation of Earth. (TNG game: Armada)

In one timeline, Kes traveled back in time from 2376 to 2371, where she attempted to turn Voyager over to the Vidiians. (VOY episode: "Fury")

In 2377, Chakotay was aided in restoring a temporally-shattered Voyager by the adult Naomi Wildman and Icheb from an alternate timeline. (VOY episode: "Shattered")

In 2377, Voyager returned to Federation space thanks to the aid of an Admiral Janeway from a timeline in which Voyager did not return until 2394. (VOY episode: "Endgame")

In a timeline in which Khan Noonien Singh won the Eugenics Wars, Princeps Julian Bashir commanded the Starship Defiance during the late 24th century. (DS9/MyrU novel: Seeds of Dissent)

Background
The majority of Star Trek stories take place in "prime reality", a singular timeline which runs from the present day through to all the Star Trek series. The prime reality has generated numerous alternate timelines, though these normally are only explored for the duration of one story. One major exception is the "mirror universe", which has been developed in multiple stories across multiple series (so much so in fact that a number of alternate mirror universes have even been seen). The 2009 movie saw a significant movement in the Star Trek universe, with the film establishing a new, which rather than being "repaired" back to the prime universe has become the new leading edge of the franchise, with new movies to be set in the continuation of this timeline rather than the original prime timeline. Meanwhile stories from across the franchise continue to be told in both the prime and new timeline, and in the Myriad Universes series even in other alternate timelines.

In his annotations for Places of Exile, Christopher L. Bennett postulates a rationalization for why divergent timelines, even centuries after the point of divergence, manage to generate the same characters, settings and scenarios, even when the same settings recurring so similarly are so improbable: Bennett suggests that because a being in a different timeline is merely one outcome for the same matter that "the physical connection across different timelines means that there can be a sort of quantum resonance: the shared "inertia" of different quantum facets of the same being causes their lives -- and their genetics -- to develop along similar lines"