You make a fine point about both Hawking and Terminator — another film that is good (like Looper) but bunks itself up with time travel. My point (for both of those films) is that the reading of time travel that they establish (whether it agree with Hawking or not) doesn’t work because they defy the rules they’ve established. It makes for some really cool visuals with the slowly amputated limbs and such, but it murks up the story. A film like Back to the Future uses this type of narrative and sticks to it; as does Twelve Monkeys. Thanks for reading!