I watched Interstellar and came out deeply disappointed. Since then, I’ve read many other reviews, of both the science and the filmmaking, and I keep thinking maybe I’m being too hard on the film. Yeah, some of the science was bad. A lot of movies have bad science, and this one also had a lot of really good science. And it’s just a movie! So maybe I should give it a pass. Maybe I should say, “It did a really great job explaining relativity!” (which it did) and leave it at that.

Brian Greene continues the WSF Live Forum all month long. Each day, he’ll answer one of your questions for this ongoing series that delves into the fundamental nature of space, time, and reality as we may or may not know it. If you traveled through a wormhole to an earlier time, would your presence create a “new” version of that earlier time or would it be the “original” version of that time? — via physicsforums.com First, bear in mind that while the notion of a wormhole finds a natural place in the mathematics of Einstein’s general relativity, there is no experimental or observational evidence that wormholes exist. Moreover, even if they did exist, it is unclear whether one could generate a macroscopic wormhole and keep it open, allowing a human to safely travel through it. So, you should consider the whole collection of ideas that includes wormholes and time travel as highly speculative. OK. Let’s speculate. If you did have a wormhole—a tunnel from one location in space to another—hen it’s pretty clear how to turn it into a time machine: move the openings of the wormhole relative to one another (so that time at the two openings elapses at …