I saw the movie Alliance a couple of weeks ago. It's pretty good, especially if you like good, mostly hard science fiction. But somethings still bothers me about it.
This isn't giving anything away that's not in the trailers, until I warn you. In the picture to the right is symbol containing a sentence (or some complicated thought) of the alien's language. The plot evolves around a linguist's (Amy Adams) ability to translate such symbols and so try to communicate with the aliens. Before this she approached them with a whiteboard on which she'd write her name or a word from English, but that didn't work.
Instead she works on translating their language. The way they show her doing this is good stuff -- she tries to break down parts of the loop (and they're always loops) into individual "words" or "thoughts" or "feelings" or the equivalent. Eventually she succeeds somewhat, but it's too late and the politicans of the world take to aggressively dealing with what they see as a massive threat to the and to Earth. (There are about 12 of these ships at various points around the globe.) Of course that ruins everything.
Now you should stop here if you don't want to risk any spoilers.
Slate had a interesting interview with a real linquist who gave some insight into how different language structure words or thoughts. And a summary of what the plot means.
Apparently the aliens experience "nonlinear time." (I didn't get this this until I read about the movie afterward.) Their loops contains subsymbols that aren't necessary in a linear time order -- the aliens think about time cyclically instead of in a straight line. Slate: "As Louise [the lingust] learns the language, she also begins gradually experiencing visions of her future, a sign that she too is beginning to experience time differently."
I don't know what nonlinear time is. I don't see how it wouldn't violate causality. I don't see how the speed of light could be a constant in all reference frames, as we know it is. (Einstein assumed that as a postulate of special relativity, and by the accuracy of its predictions we take it now as a fundamental property of the universe.) If time is cyclic, couldn't you, in particular, travel from where you are today and when and come back to the same place and time? Or at least the same time? What then if you didn't do the same thing you did the first time? How can these aliens be just a few feet from humans and experience time so radically different?
That's just one thing that bothered me. The other is that, here are these aliens who managed to come here, en masse, from who knows where in the universe. They also know something about antigravity, or altering the direction of gravity, as the early parts of the show make clear; also their spaceships hang silently several meters above the ground.
So these beings know how to do all this, and we have to translate their language?? They can't translate ours? Nonlinear time presumably has linear time as its zeroth-order leading term, and but they don't understan that? They are clearly very intelligent compare to us, but they can't translate a simple linear language?
I didn't find that convincing. Of course, the plot hangs on the struggle to understand their language before Earth's countries try to bomb them to hell out of them (trivial for them to handle). Without that struggle, the plot would collapse into much less than it is, and probably not enough.
So in these senses the movie isn't exactly hard scifi -- it alters reality for the sake of its plot. Just when they started getting to the good stuff, they pull a deus ex machina. The fact that a lot of people needed the plot explained to them afterward shows this didn't really work.
Still, it's a movie well worth seeing.