Physicists explore the reality of time travel in ‘Donnie Darko’
Throughout the 2000s, one film that seemed to be on everyone’s minds was Richard Kelly’s Donnie Darko. The film starring Jake and Maggie Gyllenhaal, Drew Barrymore and Patrick Swayze, told of a troubled teenager’s dealings with a hallucinatory rabbit telling him that the world was going to end in 28 days.
One of the most compelling features of Donnie Darko was that it explored the reality and possibility of time travel. Donnie is keen to go back in time in order to right several tragic events that he believes occurred in his past. However, many prominent scientists have claimed that the explanation of time travel within the film leaves a lot to be desired.
A crucial element of time travel within Donnie Darko concerns ‘tangent universes’. Physicist Sean Bartz once told Inverse: “Donnie Darko, like many works of fiction, takes two ideas from physics about ‘parallel universes’ and combines them. The movie also creates the idea of a tangent universe, which implies a parallel universe that contacts ours at a single point in space-time.”
The aeroplane engine that nearly killed Donnie at the film’s beginning is widely believed to have opened up a wormhole to another universe, resulting in two possible histories in the film being written simultaneously. Bartz continued: “The movie suggests two alternative histories: one where Donnie is killed by the aeroplane engine, and one where he is not and Gretchen dies instead. The existence of the alternate realities may be consistent with the many-worlds interpretation, but Donnie experiencing both of them is not.”
As for the actual wormhole, Donnie’s inquisitive nature leads him to ask his science teacher about their scientific reality. While Donnie’s teacher does not provide a thorough explanation, another physicist, Leo Stein, does. He explained: “A wormhole is a hypothetical shortcut between two different regions of space-time. This could either be between two ‘different’ universes or two places within the same universe.”
However, Stein also notes that the wormhole in Donnie Darko is not entirely believable owing to the jet engine’s lack of suitable matter. He adds: “One of the difficulties is that the math of wormholes requires something called ‘exotic’ matter, which is basically just matter whose energy density and pressure behave in a way that we haven’t observed. Jet engines are made of ordinary, not exotic, matter. So, where did that exotic matter come from? What was the mechanism for a crashing jet engine to curve space-time so much that it created a wormhole?” Evidently, the possibility of the jet engine accruing exotic matter is deemed unlikely.
Elsewhere, Ben Mummery expresses a conflicting view of the film’s scientific reality. His theory primarily concerns the actual limitations of any possible wormhole. He writes: “A wormhole is a theoretical connection between two points in space, not necessarily in the same universe. However, as we know that different points in space can experience time differently, it is also a connection between two points in time. In this regard, Donnie Darko is pretty much on the money. Dropping the jet engine through a wormhole at the end of the film allows it to emerge in the primary universe 28 days earlier. [Although] one restriction of wormhole-based time travel is that you can only go back as far as the creation of the wormhole. In this respect, Donnie Darko is unrealistic.”
Ultimately, then, despite Donnie Darko being an alluring film, full of the teenage perturbations that were exhibited in the latter part of the 20th Century, the science on which it is based is not entirely accurate. As for Frank, the strange bunny-suited being who is either hallucinated by Donnie or travels through the suspected wormhole, not even physics can explain where he comes from; he is truly a work of fiction.
