Take that, causality!

[matril]

Being a bit of a sci-fi geek - not so much as fantasy, but it's definitely a preferred genre - I've often thought about how various writers deal with the inherent paradoxes of time travel. What if something in the past is altered - how does that affect the future that the time traveler came from? It seems like there's generally two possible paths to go. One is that the past hasn't been altered; the time traveler is simply now aware that his timeline contains elements that have been affected by his travel. That's how the timeline works in Prisoner of Azkaban, when Harry sees himself, thinks it's his dad, and only later realizes it was himself all along. So there's infinite copies of himself going back in time, affecting events, and ending up in the present again. There was never any situation in which he did not go back in time and affect events. The other path is that the time traveler does actually change his own future - the first example that comes to my mind is Back to the Future. Marty changes the future to the point that he alters the very nature of his parents' relationship, even putting his own existence in jeopardy. The second path is far more problematic. If a time traveler wrecks his own existence, how could he have existed to have wrecked it in the first place? Lots of lovely paradoxes and alternate universes arise.

It occurs to me that, whether consciously or not, writers of time travel stories tend to work with a very conventional, linear super-timeline, irrespective of years or other conventional measurements of time. Sure, the traveler may jump from 1990 to 1950, but in terms of the super-timeline, 1990 happens first. 1950 doesn't happen until he gets there. Yeah, I'm probably not making much sense. What I mean is, the super-timeline is based on the chronology of the story. What happens at the beginning of the story happens before whatever happens at the end, even if it starts in the future and ends in the past. Because our minds crave linear time. We have too much trouble swallowing a story that literally has the future happening before the past. Maybe a later year shows up, story-wise, before an earlier year, but in our minds, that later year comes first, and causes whatever happens later in the story, no matter where it falls on the regular timeline. I think I need a chart to explain this better. But I have none. So I'm done.

Comments

[sreya.livejournal.com]

Hmm. Well, in Charmed, they had a character introduced that had travelled into the storyline from the future, and then proceeded over the course of the season to reveal what that future was - and using various gimmicks, also showed how that future was changed. Seemed to work there, because the focus of the storyline wasn't on the time traveller, but on the characters in the time that he travelled into. True, there was the paradox of how he could have travelled back in the first place if the new timeline gave him no incentive to do so. But at least for storytelling purposes, it worked.

[matril.livejournal.com]

That's always a tricky paradox, when the time traveler's altering of the past negates his reason for time traveling in the first place. It brings up the question of whether he's the same person at all, or if anyone's the same, since they're now from an alternate timeline. Like when time travelers screw up the timline, and they remember the way it used to be, but no one else does. Or like in Frequency, when the character simultaneously remembers the two separate alternate timelines. Makes your head spin.

[krpalmer.livejournal.com]

Time travel's definitely strong stuff to invoke. I suppose the simpler solution is to say "whatever changes you think you've made have only ensured that things will turn out the way you already know them to be"... although I suppose I have a philosophical disagreement with stories that present that idea in such a way as to suggest there's no such thing as free will. (I suppose I'd point to Robert A. Heinlein's "By His Bootstraps.") As for the other option, mind you, I don't know of very many stories where a time paradox makes the universe wink out, that not being the most positive note to end on (although I can think of the Futurama episode where Fry was shown what would have happened had he not been frozen, for a mild range of stories), but I can also wonder about "alternate universes." Does that mean the old, unoptimised world still exists somewhere, and all you've done is change the people you experience yourself? Of course, I've seen stories where the question is sidestepped altogether, and something about the universe itself won't allow major changes (for example, Connie Willis's "To Say Nothing Of The Dog.")

[matril.livejournal.com]

The subject title of my post comes from a Futurama episode in which Fry becomes his own grandfather. (Ewww!)

Good question about alternate universes - perhaps I might say that the super-timeline, following the chronology of the story rather than a year-by-year chronology, is attached to a particular character or group of characters through whose view the story progresses. The nature of their universe appears to change, while for everyone else things appear to be proceeding as normal.