WARNING! The following essay — the last lecture in our EW University course on time travel stories — may induce a migraine. Students are advised to take some aspirin before reading. Getting stoned may also help, though this cannot be encouraged or condoned by the faculty.
“Listen: Billy Pilgrim has come unstuck in time.”
With those famous words in Slaughterhouse Five (1969), author Kurt Vonnegut introduced one of the most memorable time travelers and depictions of time travel that literature has ever given us. The premise: Billy Pilgrim has gone crazy from failing to grapple with the horror he experienced during World War II many, many years before. Unmoored from sanity, the haunted optometrist convinces himself he’s been abducted by aliens who believe that time is eternally present, that past and future are happening in the now — Cubism made real. Pilgrim — his mind desperately flailing to save itself from its own existential crisis — adopts this conspiratorial perspective, as well as the sanguine philosophy that comes with it: that we are prisoners to predestined, already-written fate. And it is not a pleasant experience. “Billy is spastic in time, has no control over where he is going next, and the trips aren’t necessarily fun. He is in a constant state of stage fright, he says, because he never knows what part of his life he is going to have to act in next.”
Vonnegut’s powerful masterpiece may or may not be what you would call a hardcore sci-fi novel, although it does provide a provocative dramatization of new ideas about time described by quantum physics (and, it must be added, a perspective of reality familiar to followers of Buddhism and other mystic religions). You see the same stuff brought to life in the dark superhero epic Watchmen (Alan Moore/Dave Gibbons; 1986) in the form of all-powerful yet impotently omniscient Dr. Manhattan, a literal manifestation of topsy-turvy Relativity and the embodiment of a weapon that changed the course of history and filled the world with profound insecurity.
Both Slaughterhouse Five and Watchmen use a very different form of time travel than the ones surveyed in our previous lecture; these are examples of consciousness time travel, which allows storytellers to avoid the impossible problem of duplicated matter sharing the same space. [See also: The classic X-Men storyline “Days of Future Past” from 1981 by Chris Claremont and John Byrne; and the TV series Quantum Leap (1989-1993), which offers a slightly different, more convoluted variation on this conceit.] Slaughterhouse Five and Watchmen are also memorable examples of stories that grapple with the knotty concepts of free will, causality, and paradox that are intrinsic to time-travel science. The genre has particularly enjoyed playing with these noodle-cookers over the past 50 years, partly because they make for challenging intellectual fun, and partly because they can be used to portray the often-troubling post-modern condition of Western civilization.
Our survey begins with two of the most influential pieces of science fiction ever written, both of them by the revered Robert Heinlein: “By His Bootstraps” (1941) and “—All You Zombies—” (1959; the odd punctuation in the title is intentional). Both short stories are triumphs of madcap plotting. “Bootstraps” has the protagonists traveling multiple times between his present and future and becoming entangled with multiple versions of himself, thus snaring him in a loop and making a mess of his destiny. “Zombies” has its protagonist traveling between points in his past, becoming hopelessly entangled with multiple versions of himself, all in the name of ensuring his very existence. Departing from H.G. Wells’ The Time Machine, in which the time traveler was a basically a sight-seeing tourist, Heinlein’s time travelers are interactive to a dangerous extreme, as their actions create paradoxes, contradictions to the established timeline that risk negating all of history. “Bootstraps” and “Zombies” helped create the storytelling grammar and philosophical terms for countless time-travel stories since. They also inspired real science. In 1976, physicist David Lewis wrote one of the first scientific papers to take the idea of time travel seriously, citing Heinlein’s stories as case studies.
That said, “Bootstraps” and “Zombies” are also examples of more user-friendly forms of time-travel stories. That’s because they aspire to “closed loop” time travel, in which catastrophic paradox is thwarted thanks to properly motivated heroes blessed with an inexhaustible or conveniently repairable time machine. Case in point: Back To The Future, which had Marty McFly busting his buns to rectify the history-altering messes created by his accidental leap backward in time. But what would happen if a time traveler actually tried to produce a history-altering paradox? There have been several oft-used solutions:
OPTION ONE: Changes to the past create an alternate, parallel timeline. See: J.J. Abrams’ Star Trek (2009), in which time travel creates a new universe of possibilities, but allow the continuity of the Star Trek TV shows to remain intact. This popular creative approach also has basis in theoretical physics; the famous “Many Worlds Interpretation” of quantum mechanics posits that there is an infinite number of possible worlds for every possible branch of every possible decision, and that these infinite numbers of worlds actually exist. Somewhere. Somehow. FUN FACT! This theory was developed in 1957 by American physicist Hugh Everett, whose son may be familiar to you: his name is Mark Oliver Everett, a.k.a. “E,” the mastermind musician behind the alt-rock band Eels.
OPTION TWO: Changes to the past create a new, different future. See: season 1 of Heroes, in which Future Hiro blinks back to 2006 with his “Save the cheerleader, save the world” message for Peter. Also see the first three Terminator films. The annoying dilemma with these kinds of stories is that it presents a distracting logic paradox for eggheads who think too much. To wit: Future Ninja Hiro, motivated by his crappy circumstances, zips back in time and asks old friends to make changes in order to improve his crappy circumstances. But if his friends succeed, wouldn’t they negate the very reason for his time travel? Heroes and the Terminator franchise are variations of “The Grandfather Paradox” (first articulated in a 1943 sci-fi novel Le Voyageur Imprudent by Rene Barjavel), and scientists have been debating it for decades. Some say this dilemma proves definitively that time travel is impossible, rendering these stories fantastical wastes of time. Others believe this paradox can be resolved with a little bit of elbow grease and theater. Using the Heroes example: after changing the present to improve the future, Peter would have to “close the loop” by making Hiro go back in time to give him the “Save the cheerleader, save the world” message, exactly as it was delivered to him in the past — although this iteration of time-traveling Hiro would be playing the part of the old, now-negated Future Ninja Hiro. Not surprisingly, even many within the lab coat set find this solution much too complicated, especially because it depends on human free will and character, random variables that scientists really don’t like to consider. Which brings us to a third option, inspired, in part, to resolve objections to The Grandfather Paradox:
OPTION THREE: Time travel is plausible — but creating history-negating paradox is impossible. See: season 3 of Lost, in which Desmond Hume’s attempts to avert Charlie’s predestined death are initially successful, but ultimately foiled by a universal principle the show called “course correction.” This is a fictional variation of a scientific theory called “Self Consistency,” first promoted by two physicists, Igor Novikov and the aforementioned David Lewis (Lost fanatics should find the latter name familiar: that’s the name the show gave to Charlotte Lewis’ father), which posits that any attempt to produce paradox will be stopped. Want to save the world from Hitler’s evil by going back in time and shooting him at point blank range? Sorry: Hitler will duck, the bullet will miss, or a meteorite will suddenly fall on your head right before you pull the trigger. But other scientists have a God-sized objection to Self Consistency, as it sounds supernatural. How can the universe possibly recognize paradox? What or who is conspiring to create new circumstances to subvert the time travelers? Of course, these complaints work for Lost, whose story cultivates a debate between scientific and religious worldviews. And besides, as we saw in the season 5 finale, the show may actually adhere to a different take on time travel paradox. It all depends on what you think happened after Juliet detonated that H-bomb in the past …
And with that, the migraine just settled in, didn’t it? Perhaps it would be best if we brought our course on pop-culture time travel to a close. Please know that like any general survey course, we have covered only the basics. There’s a wealth of serious sci-fi literature and serious science that digs deeper in to the subject and expands the breadth of possibilities. It’s fun stuff to investigate (or at least I think it’s fun); check out the recommendations below for where to start.
EXTRA CREDIT READING AND VIEWING: The New Time Travelers by David Toomey (2007), a user-friendly non-fiction book about time-travel science; Primer (2004), an acclaimed indie flick written and directed by Shane Carruth, much praised by geeks for its rigorous, hard sci-fi approach to time travel; and conversely, What The Bleep Do We Know? (2004), a documentary-style feature which takes a more mystical view of quantum leaping. I am also a zealous user of Wikipedia, which provides deep entries for many of the terms and titles mentioned here. It’s a great place to start, but you’d be better served researching the source material they describe and reference.
Gallery: 17 favorite time travelers