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+--- Thread: Which movies get the science of time-travel right? (sci-fi hobbies) (/thread-5803.html)
Which movies get the science of time-travel right? (sci-fi hobbies) - C C - Jul 24, 2018
https://www.forbes.com/sites/startswithabang/2018/07/21/ask-ethan-which-movies-get-the-science-of-time-travel-right/#300270159e09
EXCERPT: . . . No one remembers *Timecop*, *Hot Tub Time Machine*, or *Bill & Ted's Excellent Adventure* for their incredibly accurate portrayals of time travel or a time machine. *Idiocracy* involves time travel only in the sense that time passes, even while inanimate objects (or people) remain inanimate. (Although, at least the "Time Masheen" is accurate.) Superman rewinds time to save Lois Lane's life in the original *Superman* movie, but that's due to superpowers, not science. Ditto for the recent *Doctor Strange* movie, or the cult classic *Warlock*, or *Harry Potter and the Prisoner of Azkaban*; using magic as the mechanism for time travel isn't going to score you very many science points. In a great many films, time travel is more of a plot device than anything resembling scientific accuracy. Even *Army of Darkness*, fun though it is, doesn't have a viable mechanism for the time travel it invokes.
But some films, even though they don't talk about or depict the mechanism of time travel in any detail, do admirably succeed in describing how time travel would actually work. Traveling forward is easy: you go close to the speed of light, you return to your departure point, and now you're far in the future. This is how *Planet of the Apes* sent a human far into the future on a dystopian Earth, and why Star Wars is so dissatisfying when they engage the hyperdrive. Going fast has real consequences for the passage of time, bringing you into the future no matter what else you do.
Going back in time, particularly to a fixed location in the past, is a staple of time travel movies. There are two theories about how this works:
The timeline is fixed; all that happens is written already, and when you travel back in time, you cannot change the course of events. Your time travel is already written into the timeline.
The timeline is malleable; the changes you make by going back in time will lead to a different future, perhaps even negating your own existence.
Two great examples of the first theory are *Twelve Monkeys* and *Looper*, where the future is already written. Traveling back in time allows you to live and interact with the past, but it doesn't change the course of history. The events that unfolded to cause you to go back in time have already occurred. You're simply living out your life, knowing full well what the world's destiny is.
On the other hand, there's the possibility that your future isn't written, even if you yourself came from the future. The Back to the Future franchise and the Terminator/Terminator 2 movies are very sensitive to this. Even though they're light on the details of how time travel physically works, save for a few key component ingredients, the actions that the time-travelers take can alter their future. Kyle Reese/Sarah Connor can avoid or delay judgment day, battling a terminator sent back to murder (or prevent the existence of) the boy that will battle the rise of the machines. Marty McFly travels through time to save his friend's life, but has to ensure he doesn't prevent his own existence in the process. These are two of the best examples of a time travel movie where the future is alterable. The 2009 Star Trek, Star Trek: First Contact, and Star Trek IV: The Voyage Home all play with this as well, to great effect.
There are two movies that stand out for scientific accuracy in time travel while including a great level of detail: *Interstellar* and *Contact*. Both movies, ironically, consulted with the same scientist, Kip Thorne, and both take advantage of the black hole/wormhole idea. Deep in the gravitational field of a black hole in Interstellar, time passes at a different rate, leading to a relativistic twist late in the movie. In *Contact*, a seeming instant on Earth coincided with a nearly-day-long excursion across the galaxy and, potentially the Universe. The physics of wormholes, black holes, and General Relativity is on full display in these films, and in spectacular fashion no less.
Finally, there's perhaps the most realistic and interesting movie to make use of time travel in the "time loop" sense: *Groundhog Day*....
MORE: https://www.forbes.com/sites/startswithabang/2018/07/21/ask-ethan-which-movies-get-the-science-of-time-travel-right/#300270159e09
RE: Which movies get the science of time-travel right? (sci-fi hobbies) - Magical Realist - Jul 25, 2018
Primer did a good job at showing the enormous complexity involved with time travel and changing the past..