Why It's Important to Contemplate How the Time Loop Works
Part One: Recursion vs. Iteration
Computer scientists would probably be familiar with recursive vs iterative loops. For those who aren't, here's an analogy; imagine you wish to read a book five times. There are two ways to accomplish this:
- Have 1 copy of the book. Once you reach the end, flip the book back to page one and read the copy again. This is recursion.
- Have 5 copies of the book. Read all 5 copies. This is iteration.
Consider that in the second method, you're technically reading 5 books, they just all happen to have the same content. The same applies to time loops: if it's the iterative sort, then time is still going forward and days are still passing by, each day just happens to look identical to the last.
Why is this important, you ask? In most stories the loop rewinds time, making the loop the recursive type (and also Time Travel), so it's not. But if the story explicitly defines what causes the loop, for certain causes it must logically extend that the loop is iterative - for example, if your justification for the Ripple-Effect-Proof Memory is a simple 'they're immune to the phlebotinum', this would make your time loop iterative by definition.
To explain why, imagine you've spilled a glass of water in one loop. In the next loop, you find the water is actually magic time-loop-independent water and remains spilled. But for it to ever be spilled, there must be some point in the past you spilled it in the first place. Ergo, the previous loop must have happened instead of being overriden by your current one. The ramification then is that actions can have consequences, so characters might find that their reckless abandonment causes them to end up Deader than Dead, for real.
Part Two: What's the Range of the Time Loop?
Something else worth thinking about is the extent of the reset. If the time loop is localized (for example, only the town is affected), then
A) there is a possibility someone from outside the time loop will walk in, and
B) given enough loops, the temperature and later the seasons will change as Earth continues its orbit around the sun.
With different staring conditions and factors your time loop will probably cease to be a time loop, although it might be a Close-Enough Timeline. (Admittedly, chaos theory
suggests that with a system as complex as Earth the characters doing things slightly differently, even if the overall action is the same, could end up with a completely different day.) With A, how the outsider will be affected when the loop resets needs also to be thought about.
