Friday, January 23, 2015

Time travel and determinism in three 2014 movies

I know basically three theories about time travel:
1) it's impossible
2) you would go back but into a parallel universe
3) you would go back but your actions would have to be consistent with future events.

The first two are compatible with indeterminism the last one with determinism. The problem with movies that assume time travel is that, when they choose indeterminism they are very slack about how little changes in the chain of events would get amplified in the future. Even a movie called the "butterfly effect" doesn't take it seriously.

"The name of the effect, coined by Edward Lorenz, is derived from the metaphorical example of the details of a hurricane (exact time of formation, exact path taken) being influenced by minor perturbations such as the flapping of the wings of a distant butterfly several weeks earlier." Wikipedia

Which means that even if you appeared my just milliseconds in some desert location, perhaps in the middle of the ocean, no one has even seen you, that appearance would change the weather patterns significantly in such a way that it would change, after a few weeks, among many other things, the thought patterns of the entire human population (including news, etc). Which means that, just by going back in time a few years and appearing momentarily in a desert location, you would be creating a future where the self that made that trip would not exist. In fact, in a non-deterministic perspective of reality just making time run again, even if all the details were the same, would yield different futures. Because, in a non-determinist perspective, the exact same causes do give rise to different actual events (they do give rise to the same set of possible events, but then the one that gets chosen from that set is taken unpredictably).

Now, we have no idea whether the universe works deterministically or not, or even if there are parallel universes (like Everett, Deutsch and other physicists have argued). But if it doesn't it is impossible to predict what will happen from our actions. The future becomes so unpredictable that we can't go back to change the past and make it this or that without changing everything else (unless for tiny time travels, with just a few minutes perhaps).

So, in a story-telling perspective, determinism is much more appealing, but, so far, I had only seen the 1995, Terry Gilliam's "12 monkeys". But now I saw three movies that render time travel in a deterministic perspective, and so far as I can see, do it extremely well, they are:

Time Lapse

All from 2014! Now perhaps there are really lots of movies out there that I don't know of that deal with time travel well, but I was pleasantly surprised with these three. At least something coherent! Great! Let's have more like that!

From our human perspective determinism is not easily imagined, because we necessarily see ourselves as free. I think these movies (especially the last two) make it much easier to understand that there is no difficulty in compatibilizing our inner feelings of having free will within a deterministic world. Of course that does nothing to show that the world is in fact deterministic. But at least it opens up our imagination to what, as far as we know today, might be a real possibility (non-determinism is also a real possibility but it is much more difficult to depict in a movie, essentially because it does not apply only to human actions, everything would be happening slightly differently, you might "correct" something in your past, only to be overwhelmed by a huge set of unrelated differences regarding which you would have no control).

PS - as you might deduce from this text I don't expect the movie industry to just entertain me, I would also like that my conceptual abilities be expanded as well, when I go to the movies.

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