Causality
Loops:
One reader mentioned quite reasonably that to most people, this stuff is a little bit esoteric for ready comprehension. And they’re totally right. They didn’t spend three days banging their heads against their computer screen, drawing diagrams, and pestering friends and family to see if this particular invented reality seems realistic, and why.
...or maybe they did...? There were so many cool theories about why the loop does or does not happen. What most delighted me were those who came up with complex theories (utilizing colors, letters, and so on to distinguish the timelines)..
In any case, I’m going to pictorally explain it now, the way I see it. I might even do the same for some of the more cool other theories as proposed by readers.
Here is sixteen-yr-old Ranma and twenty-three-yr-old Ranma. Younger Ranma is wearing blue, and has longer hair. Ranma with the short hair will serve as the older Ranma, the one wearing green.
Figure 1: Blue (16-yr-old)
& Green (23-yr-old) Ranma
Neither Ranma is particularly happy to be here, so be nice to them. ;)
So here’s the set-up at the beginning:
Figure 2: The basic
timeline, as is
Initially, Blue Ranma (16-yr-old Ranma) is in 1998, and Green Ranma (23-yr-old Ranma) is in 2004. Makes sense so far, right?
Then, a force is applied, via Ryoga, on Blue Ranma:
Figure 3: A force is applied
(by Ryoga) on Blue Ranma.
This force sends Blue Ranma to 2004.
Figure 4: The result of the
action of that force
Since the two Ranmas cannot occupy the same space OR the same time, Green Ranma is shunted back to 1998. If you are familiar with high-school physics, you can view these two forces as action-reaction pairs, with an equal but opposite force sending Green Ranma back. Now, 16-yr-old Ranma is in her own future, and 23-year-old Ranma is in her own past.
Figure 5: According to the
laws of Newtonian physics, an equal but opposite force is felt.
Now comes the truly tricky part: what happens if Green Ranma stays just where she is, and Blue Ranma never returns home either? In 2001, Green Ranma will be twenty-six years old.
Figure 6: 23-yr-old Ranma
(purple) & 26-yr-old Ranma (green)
Why is there a Ranma still in 1998 depicted here? (I thought she was gone! you may be thinking.) The reason Ranma is there is that the past has happened, no matter what. The only difference is that now, that is really 23-yr-old Ranma, not 16-year-old Ranma. Remember? 23-year-old Ranma got shunted back to 1998, and, as our hypothetical, we stated that she stayed there. So, in 1998, we’ve got a 23-yr-old Ranma. She’s purple, here. By 2001, she will be 26.
But it gets more complicated. What happens when Green Ranma reaches 2004? Well...
now
23--> <--
now 29
Figure 7: ...and that’s the
actual causality loop, folks! (Tips hat.)
...because of Ryoga’s action in the past, she will be shunted back to 1998. Only now, instead of being sixteen, or twenty-three in 1998, she is actually twenty-nine. While Purple Ranma gets delivered to 2004 quite intact, (due to the reciprocal force) and very happy to have only lost five and a half days of time with her husband, Green Ranma goes back to 1998 – again. This cycle can (& will!) repeat indefinitely until she dies of old age. Not a fate you’d wish on anyone! Basically, in this case, Green Ranma is the sacrifical Ranma. She saves all other versions of herself, allowing them to be parted from Ryoga for less than a week – but she herself pays the ultimate price. (At least she does in this VERY linear model of time.)
And that is Version I of events.
So, what happens if they do switch places – in other words, if Ryoga sends Blue Ranma back to her own time, eventually, as happened in the story? Figures 1-5 all still happen. Then what?
Figure 8: A different
approach
Once I realized that my first idea ended in tragedy, I set about to find a new way of thinking about things. First, I acknowledged that the Ranmas had each lived 5.5 days, away from their respective times. That is demonstrated above by the green or blue colour of their timelines (length greatly exaggerated for effect, of course!) So what happens when Ryoga exerts the force that sends Blue Ranma back to her own time?
Figure 9: Ryoga exerts the
chi Force in 2004 + 5.5 days
From a linear point of view – say, Soun’s, since he’s not even a part of our future story – Ryoga tossed Ranma into the future and pulled her back again a mere hour or so later.
The sequence of events, from Soun’s point of view, goes something like this:
1) pond, owie, etc.
2) Ryoga sends Blue Ranma to her future.
3) Green Ranma lies on the bed, passed out for a half hour or so, in her
own past.
4) Ryoga-in-the-future sends Blue Ranma back, replacing Green Ranma.
Thus, the net time that Green Ranma spends in the past is less than half an hour, from Soun’s point of view!
Thus, in real time, or linear time, Blue Ranma is only ‘gone’ from 1998 for mere minutes.
Meanwhile, in the future, from a linear standpoint, things are different. To, say, future-Ryoga, it seems that his wife was there with him, then Blue Ranma popped up. She did not disappear in minutes; she was with him for five and a half days, nearly a week. Then, he sent her back, thereby getting his wife – Green Ranma – back.
The long and short of it is that, in this set-up, the past where Ryoga and Green Ranma got closer, and Ranma had a nervous breakdown, never happened. Nope. Gone. Whereas the future, where Blue Ranma and Ryoga got closer... did.
So what happens now? Basically, Blue Ranma has her memories of the future, and Green Ranma has her memories of the past... which now never happened. I suppose that, in the story, I should have made Green Ranma, Ryoga’s wife, have no idea what had happened to her (because now it never did), but there were a handful of reasons that I did not. The first is that I knew that this would be greeted with a general “whaaaat....?!”, and that it would take just about this long to explain where that had come from, why it was plausible. Second, it has a “and then she woke up!”/pull the rug out from under the reader feeling, which is a total no-no in fiction of any kind. The third reason is that I needed Green Ranma to fill in the readers as to some casuality stuff. “Will she remember?” Ryoga asks, and all of that scene. The fourth reason I’ll come to in a minute.
Figure 10: the initial
timeline in 1998 now never happened.
Now, what will happen when Blue Ranma reaches the age of 23? Yes, you guessed it: she will go back in time, just as Green Ranma did. Just as Green Ranma did, she will doubt herself, woo Ryoga, go to the fair in her kimono, and demonstrate general angst as she fears that the whole thing has been a dream. After all, she has no way of knowing that Green Ranma has ‘already’ done the exact same thing. But Ryoga will save her in the end, and she will return to her own time – just as Green Ranma did. In matter of fact, she has become Green Ranma.
As a matter of fact, she was all along.
Do you have a headache, yet?
At least
with this second version of events, neither Green nor any other kind of Ranma
ends up stuck in the loop for all eternity.
Like vacationers in
So by now, if you’re still here, and your brain has not exploded, you may be wondering a couple of things:
1) Wait. So you’re saying Ranma guessed Sachiko’s age?
2) Why did the past and future shift like that when it’s obviously the same, now?
3) Why on earth does Green Ranma remember where she was at all?
Heh. Now we get complicated.
The multiple-universes/parallel worlds theory is the one I really like. Why do I like it? Er... ‘Sliders’ was an awesome show until they began to replace characters...? Well, I also like the concept because it is basically carte blanche to do anything with the plot I darn well please.
Why and how? Well, the theory of parallel universes states that a completely new universe could have been laid atop the first, the moment that the first incidence in which time travel took place. Parallel universe theory states that for every choice we make, there is a choice we did not make, and a universe in which we did make that choice. To quote an example from a reader (thanks!), you may have become frustrated with this tutorial by now, and stopped reading. There was a point (around when Purple Ranma showed up and you felt completely confused) when you thought you might. Instead, you kept reading.
Or so you think. Parallel universes states that there is now a completely brand-spanking-new universe where you threw up your hands and decided to play ‘Resident Evil XIV’ instead, and another where you decided you really ought to just re-read the story, and yet another where you turned off your computer and went outside to sit in the sun.
Eventually, these universes grow unwieldy and begin to grow together, like a grapevine. At first, the vine goes in all directions. Eventually, the vine runs out of space, and begins to grow together. Universes are similar. The multiverse has a ‘carrying capacity’, and once it is reached, universes blend together.
This ‘blending’ is what Blue Ranma was experiencing when she ‘remembered’ how old her baby was; and this is what Green Ranma was experiencing when her vision of the future seemed to go a bit double. The universes were trying (and failing) to become one.
That said, this means that Green Ranma and Blue Ranma are in parallel universes. Not the same one.
Not the same timeline at all, albeit a very similar one.
Let’s go a bit nonlinear, shall we?
Figure 11: Ryoga sent Ranma
to a Parallel Universe!
Things go for five and a half days in each timeline, completely disparate from the other; but then there’s that interesting tendency for similar alternate universes to merge. The fact that Blue Ranma remembers how old Sachiko is, and that Green Ranma has a sense of a shifting future are signs that this is beginning to occur.
A simplistic explanation for why this happens is actually because of what Ryoga did. Merging universes are said to have the same ‘outcome’. In this case, the outcome was Ranma falling for Ryoga and eventually marrying him. When the outcome for both Ranmas was the same – essentially, the time at which Blue Ranma would also definitely marry Ryoga – their universes joined, became one universe...
Figure 12: The blending of
two disparate universes to form one outcome: marrying Ryoga
This explains why Green Ranma remembers what happened in 1998; in this version, the events never ‘disappear’ as they do in Version II. So both Ranmas remember what happened – there is no causality loop – and there is a certain amount of ‘bleed’ in terms of the ‘facts’ and ‘truths’ of one universe to another, before the two parallel worlds become one. Pretty amazing, huh?
So, after much deliberation, this is the one I picked: Version III.
And by now, you are either very very impressed or very very frightened. More power to you if you finished this explanation! :)
Finally, let me make note of my limited Physics background and even more limited Quantum Physics background. If episodes of 'Sliders' and 'Quantum Leap' count, though, I'm a full-fledged expert.
