30

This was prompted by a previous question I had here, but I decided it was a good stand-alone question.

This is a general science fiction question and not specific to any particular world.

Is there a difference between a parallel universe and an alternate universe? It seems the two words are used interchangeably, but according my last question, they might be considered two different things. If they are different, what makes them different? And if they are the same, do you have any proof or anything that might back up your claim?

12

They're not the same thing. Taken from the definition of parallel universe:

A parallel universe or alternative reality is a hypothetical self-contained separate reality coexisting with one's own

And from the definition of alternate universe:

An alternative universe (also known as alternate universe or alternate reality), commonly abbreviated as AU, is a type or form of in which canonical facts of setting or characterization in the universe being explored or written about are deliberately changed.

So looking at the definitions, we see some differences. A parallel universe would be a completely separate universe, possibly containing similar characters or facts, but definitively a separate entity. An alternative universe would likely take place in the same universe, but with altered facts (i.e. "what-if" scenarios).

Using Star Wars as an example, as that's what I'm most familiar with, E.T. would be (mostly) a parallel universe to Star Wars. An alternate universe would be something appearing under the Star Wars: Infinities label (deliberately non-canon stories) or fan fiction not approved by Lucas Enterprises.

  • 3
    The definitions seem to indicate that they are the same: "or alternative reality" ... "or alternate reality"... – NominSim Jun 29 '12 at 15:17
  • 1
    No, those are what they are sometimes known as. That is why there is confusion (the whole reason the question came up in the first place) - the two terms are often used interchangeably. But if you actually read the answer, you notice the definitions are completely different. – The Fallen Jun 29 '12 at 16:32
7

Parallel universe is a term describing a (theoretical) physical concept of having a similar yet somewhat different universe separate from the "given" one; this concept may be used as one of the elements in SFF setting.

Alternate universe is a term describing a literary (or other media) technique of pretending that an existing universe is somehow different.

Bear in mind that neither has an "official" definition in SFF and as such, it is quite possible that different works/authors can use either one with different connotations or even meanings.

6

Writers aren't very strict when it comes to these two particular terms. Most of the time, the two terms are interchangeable, unless they've been defined to be different within that continuity.

For example, in Star Trek, the word "parallel" is taken to mean "alongside", not that the two universes developed in parallel/mostly in parallel. They have timeline splits for universes that were identical up until the divergence point, an antimatter universe that appears to be otherwise completely identical to ours, and at least one "parallel universe" that's on a difference plane of existence.

  • 1
    That said, I'm of the opinion that "alternate universe" should be an umbrella term for "parallel universe" and other, non-parallel universes, like the Sphere Builders, who have nothing in common with our universe. – Izkata Jun 28 '12 at 23:01
5

When I think of parallel I see this: Parallel Lines

When I think of alternate I see something like this:

alternate

What I'm heading at is that I think if a universe A is parallel to universe B then they were both created at the same time. And if universe C is alternate to universe D then either one of them was created first and the other one is a "spin off".

========

Parallel universes will have same tendencies and/or directions as well as have comparable parts, some analogous aspects and/or recognized similarities.

I can only assume that alternate universes will change back and forth between some conditions and/or states, actions. I don't think that alternate universes would have same direction (I might be wrong about that so don't quote me).

This picture

enter image description here

should shed some light on this topic.

3

Think of an alternate universe as a line that as it progresses through time more and more branches "generate" from the "original" line. So each bifurcation represents a different outcome of any situation; for example, this morning you had the option to stay home or go to work, but you chose to go to work, an alternate universe would branch off from the decision of not going to work. A PERFECT example of this would be the "Butterfly Effect" movies, somehow the protagonists can travel between different lines of the same but ALTERNATE universe... furthermore, in that alternate universe there is not another version of the same person: this is another way how parallel and alternate universes are different; if you travel to a parallel universe you will find a slightly different version of yourself, a perfect example would be the series "Fringe". In Fringe when a protagonist travels to the parallel universe then he/she finds another version of the self (however in the series they sometimes refer to the parallel universe as alternate universe which is incorrect). A HUGE DIFFERENCE is that parallel universes (as the name suggests) NEVER touch each other, and if they do it would theoretically destroy one or both of the universes (as in Fringe); Alternate Universes generate from ONE SAME universe so at some point in time they were the same.

EDITED:

One more thing, Fringe got it wrong about Deja Vu's... Deja Vu's are nothing but the impression of recalling something not a window to an alternate universe. So what causes Deja Vu's? The best explanation I've read states that our brain uses a chemical compound when we are trying to recall something in order to help remember faster and better; when we have a Deja Vu it simply means that that chemical has been produced mistakenly when we were not trying to remember anything.

2

The terms are essentially interchangeable; some people may make distinctions, but there is no consensus.

The people of the Science Fiction Citations site have studied the usage of these terms (alternate reality, alternate world, parallel universe, etc.) more seriously than anybody else; they have considered most every combination of adjective and noun you can think of, and they have dredged a large body of literature for evidence. Here are their definitions (follow the links to see many historical examples of the use of each term):

alternate reality = alternate world

alternate universe = alternate world

alternate world one of many possible universes, which may have different physical laws or a different history than our own

alternative reality = alternate world

alternative universe = alternate world

alternative world = alternate world

parallel universe A universe in which physical laws or historical events are different to our own

parallel world A world like our own, but which has [differences] in history or physical laws to our [own]

If these three definitions are not exactly the same, the differences are obscure and insignificant. Jeff Prucher's Hugo-winning book Brave New Words: The Oxford Dictionary of Science Fiction is largely based on the material at the Science Fiction Citations site. The definitions in Prucher's book differ slightly in wording but amount to the same thing:

alternative world n. one of many possible space-time continua, having a different history or physical laws than our own space-time continuum

parallel universe n. a universe or space-time continuum that exists alongside ours, and which may possess different physical laws or a different history. Also used fig. Compare PARALLEL WORLD.

parallel world n. a PARALLEL UNIVERSE.

Of the terms discussed here, only parallel universe and parallel world have entries in the online OED at this time:

parallel universe n. (a) (orig. and chiefly Science Fiction) a universe conceived of as existing alongside or in addition to our own, having many similarities to it but usually differing from it in some significant way; also fig.; (b) (in the many-worlds interpretation of quantum mechanics) a universe regarded as actually existing alongside our own, albeit with no possibility of detection (see many-worlds n. at MANY adj., pron., n., and adv. Compounds 2).

parallel world n. fictional or hypothesized world held to exist alongside or in addition to the known world; = parallel universe n.

1

Sorry that I'm very late in this game, but here's my two cents about all this. Parallel universe and alternate universe can be distinguished, as seen above. But they could also be one and the same, at least in the realm of science fact. (Sorry if I'm posting this on a science fiction group.)

I'm having in mind the many-worlds interpretation and other multiverse interpretations in the field of quantum physics. In a nutshell, such hypotheses posit that all alternate or "what-if" histories, both that have already occurred and will occur in the future, take place in real life, just that they're in parallel universes or alternate universes. This way, "what-if" histories don't have to be restricted to the realm of a fictional alternate space in this universe - in other words, not restricted to the conditional, as in to the "could have been", "would be", etc. And multiverse theories could serve to reduce, if not eliminate, the suspension of disbelief in terms of alternate histories. It's possible that there's an infinite number of such universes in the cosmos.

Having said that, alternate histories or alternate universes could still be considered fictional, though often based on plausibility, in the sense that one can only approximate, based on real-life examples from our own universe, what such parallel/alternate worlds are like.

  • Add references (links, pictures if you can) and try to switch from a personal standpoint to a third person perspective. Your answer is valid, but this site is big on people acting as repeaters, rather than originators, of ideas. Still, here's your first +1: keep it going, make the changes, and have a good time. – Carpe CM Aug 10 '16 at 16:50

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.