Stacked butterfly effect?
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not exactly, what i was trying to get at.
John Titor's time machine has a range of 60 or so years before the worldline becomes completely different and its not necessarily that people make that change time, sometimes the change is just an atom moved 2 centimeters to the left. or the wind blowing pollen to a different flower.
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Ah, then it seems like a mix of two particular 'mythologies' of parallel universes.
The first is series of books that I forget the name of (having read them at least two decades ago) where Time Travel is merely moving across a skewed set of alternate worlds, like taking a stack of playing cards, nudging it into a diagonal and drilling up and down the vertical. The gist being that travelling to "200 years ago world" indeed sends you a world generally consistent with being 200 years ago, but 200 years into that world's future isn't 'now', but just happens to be the contemporary "200 years ago world" to our own one after 200 years have passed. And with both there and here having had 200 years (potentially) of inter-world commerce between themselves and all the others to change how their history happens. (And our future not the same as a future-partner world had.)
The second is that the "Universe Next Door" is a parallel universe because it differs by a little bit, the one next to that differs by slightly more, etc. So that in JT's case it looks like the skewed-history parallel-worlds are also 'nudged-history' (Probably because of subtle but increasing amounts of different starting conditions to them... and/or 'time constant', after all, the 'now' skew could be because the 'cards' are all slightly different scales but with the 'starting' edge vertical.) But unless the starting conditions are arbitrarily small compared with the time-slip, I agree with the poster who thinks that they'd be completely different, as the differences over the life of the universe would build up massively. If that's what he was saying.
the rest of you're post was a compilation of movie and short story references. Of which i found irrelivent.
Exemplar. I thought they'd be useful anchors for a common understanding. Much as (without any irony) I used at least one exemplar from fiction (the other being so generic I didn't actually bother to tie it down to any particular example) in the first bit of this post. However, I think I did go overboard, the last time, but I wasn't exactly sure which ones everyone would understand.
BTW: All my best to rarborman's brother. He either needs help or we need his help. Whichever it ends up being (and I won't rule out that it's the latter), I hope the situation resolves itself without too much grief.