Minority Report has been on my mind lately, probably because of that Engadget post about motion controlled computers. Here's what it looks like in the movie. My thought on it, by the way, is that the detection anchor should be mounted on the torso, so only the movement of the hands relative to the body are counted, but not the entire person walking. Alternatively, maybe there can be some sort of face recognition, so the system can calculate where the eyes are and use that vector to determine which object to move.
Anyway, thinking about Minority Report led me to other time discrepancy movies, like The Lake House, which ended with a discussion between my friends about whether the movie can be fitted into the physics understanding of time. Our conclusion was that it can't, for reasons I don't really feel like going into.
A more interesting movie though, which I think has more implications for time "travel" of sorts, is The Jacket. For most things, The Jacket has a more consistent overall timeline than The Lake House does. All the information Adrian Brody's character needed he got from the future, from the person he then went back and told that same information to. Which, although circular, only results in one timeline.
The interesting part of the movie is how he "changed the future" through his actions. In theory this is the same thing as what happened in The Lake House: some information was sent back to the past, which changed the future. The reason why The Lake House causes problems is that we don't only follow one character, but two characters whose past doesn't change. Sandra Bullock's character first experiences the car crash, then tells Keanu Reeves' character about it, which eventually leads to the crash not happening. But then what happened to the memory of the crash? It remains, and here lies the dilemma: you can't have a memory of something which didn't happen.
How did The Jacket get around that? Simple: Kiera Knightney's character didn't keep the memory. After the future is changed, she does not have any memories of what happened before at all. Instead, we see her starting afresh, at the same location as where we first saw her in the future. Hence you can say that the future was sent down another branch entirely, not kept on the same branch but changed the middle.
What about Adrian Brody's memory? Well, the film never actually shows his time line past his death. It is not the case that these two time lines meet, but that his was cut into pieces, and a few of these pieces were placed in the future. Therefore, when he is in the future, he does not have knowledge of what happened to him in the "past" (that is, after he was pulled out of the morgue drawer for that particular trip). Which, again, allows the film to maintain internal consistency.
So that's one reason why I like The Jacket more. And I suppose I should credit my attraction to random and slightly awkward romances.