As a scientist (albeit, not a physicist) I often ponder “is time travel possible?”. The answer is, obviously, I don’t know. Maybe it is.
There are a large number of time travel theories. On one hand if it were possible to travel backwards in time, would we not be surrounded by billions of people from many years into the distant future who have come to visit us? Then again, why should they visit now when they have a virtually unlimited number of eras to view instead.
Regardless, maybe they are in fact here? Maybe it is possible to visit us, but there are rules? Time travel movies frequently toy with these ideas, with the complex connection between cause and effect, past and future.
One very good example is the film Timecrimes. Although a large portion of it is unsurprising and can be said to repeat the standard time travel genre, at some point during the middle of the movie it breaks from that and begins asking questions that aren’t often investigated: what is cause and what is effect? It does so in a very convincing and exciting way, and when I left the movie theater I couldn’t help but ask myself why so few movies deal with those fascinating issues.
In most movies that deal with time travel one of the following scenarios may occur:
(a) The hero may journey back in time and alter something and create a paradox (these stories tend to contradict themselves almost every single time).
(b) The hero may go back in time only to discover he can’t alter anything - he is a part of history.
(c) The hero may travel back in time only to examine an historical era (in a sense, this needn’t be a science fiction movie).
(d) The protagonist may journey to the future - in a way this is not a time travel film but rather a futuristic movie (think ‘Buck Rogers’ - an astronaut gets frozen for 5 centuries and wakes up in the far future).
All these are intriguing notions. Until they are resolved by science, I will enjoy whatever films and novels are created about the subject despite any (fundamental) flaws.