Time Travel

by James Gleick

  Like H. G. Wells, Proust absorbed the new geology. He digs in his own buried strata: “All these memories added to one another now formed a single mass, but one could still distinguish between them—between the oldest, and those that were more recent, born of a fragrance, and then those that were only memories belonging to another person from whom I had learned them—if not fissures, if not true faults, at least that veining, that variegation of coloring, which in certain rocks, in certain marbles, reveal differences in origin, in age, in ‘formation.’ ” We might criticize Proust’s view of memory as merely poetic if our modern neuroscientists had settled on a more authoritative model of how memory works, but they have not. Even with the example of computer storage to draw on, even with our detailed neuroanatomies of the hippocampus and the amygdala, no one can really explain how memories are formed and retrieved. Nor can anyone explain away Proust’s paradoxical contention: that the past cannot truly be recovered by searching our memories, by interrogating them, by rewinding the film or reaching back into the drawer; rather, that the essence of the past, when it comes to us at all, comes unbidden.

  He invented the term “involuntary memory” for this. He warned: “It is a waste of effort for us to try to summon it, all the exertions of our intelligence are useless. The past is hidden outside the realm of our intelligence and beyond its reach.” We may think, peering naïvely into our minds, that we have formed our memories and may now call them up for leisurely inspection, but no, the memory we reach for, the memory of the conscious will, is an illusion. “The information it gives about the past preserves nothing of the past itself.” Our intelligence rewrites and rewrites again the story it is trying to recall. “The mind feels overtaken by itself; when it, the seeker, is also the obscure country where it must seek.” Involuntary memory is the grail for which we may not quest. We don’t find it; it finds us. It may lie hidden perchance in a material object—“in the sensation that this material object would give us”—for example, oh, the taste of a petite madeleine dipped in lime-blossom tea. It may come in the liminal space between waking and sleep. “Then the confusion among the disordered worlds will be complete, the magic armchair will send him traveling at top speed through time and space.”

  All things considered, it may seem surprising that it took psychologists sixty more years to define this phenomenon and give it the name “mental time travel,” but they have done that now. A neuroscientist in Canada, Endel Tulving, coined the term for what he called “episodic memory” in the 1970s and 1980s. “Remembering, for the rememberer, is mental time travel,” he wrote, “a sort of reliving of something that happened in the past.” Or the future, naturally. (It’s a poor sort of memory that only works backward, remember.) It’s MTT, for short, and researchers debate whether it is a uniquely human capability or whether monkeys and birds may also revisit their pasts and project themselves into the future. A more recent definition by two cognitive scientists: “Mental time travel is the ability to mentally project oneself backward in time to relive past experiences and forward in time to pre-live possible future experiences. Previous work has focused on MTT in its voluntary form. Here, we introduce the notion of involuntary MTT.” In other words, “involuntary (spontaneous) mental time travel into the past and future.” No mention of madeleines, though.

  Everyone seems to agree that our imaginations liberate us in the time dimension, even if we can’t have a Wellsian time machine. But not Samuel Beckett. The young Dubliner, who had not yet written any of his novels or plays, studied Proust in the summer of 1930 when he was at the École Normale in Paris, in order “to examine in the first place that double-headed monster of damnation and salvation—Time.” Freedom is not what he saw. In Proust’s world he found only victims and prisoners. Not for Sam “our pernicious and incurable optimism,” “our smug will to live,” averting our eyes from the bitter fate that lies ahead. We are like organisms of two dimensions, he suggests, like the inhabitants of Flatland, who suddenly discover a third dimension, height. The discovery avails them nothing. They cannot travel in their new dimension. Nor can we. Beckett says:

  There is no escape from the hours and the days. Neither from to-morrow nor from yesterday. There is no escape from yesterday because yesterday has deformed us, or been deformed by us….Yesterday is not a milestone that has been passed, but a drystone on the beaten track of the years, and irremediably part of us, heavy and dangerous.

  Beckett will leave to others the pleasures of time travel. For him time is poison. It is a cancer.

  At the best, all that is realized in Time (all Time produce), whether in Art or Life, can only be possessed successively, by a series of partial annexations—and never integrally and at once.

  At least he is consistent. We can wait, that’s all.

  VLADIMIR: But you say we were here yesterday.

  ESTRAGON: I may be mistaken.

  —

  ANY BOOK—bound and sewn, with a beginning, middle, and end—resembles the Universe Rigid. It has a finality lacking in real life, where we can’t expect all the threads to tie together when we’re done. The novelist Ali Smith says that books are “tangible pieces of time in our hands.” You can hold them, you can experience them, but you cannot change them. Except that you can and do: the book is nothing—inert, waiting—until someone is reading it, and then the reader, too, becomes a player in the story. Reading Proust entangles your memories, your desires, with Marcel’s. Smith retranslates Heraclitus: “You can’t step into the same story twice.” Wherever the reader is, on whatever page, the story has a past, which is gone, and a future, which has not yet come.

  But surely the reader is capacious, with memory big enough and reliable enough to take in an entire book. (A book is only a few megabytes, after all.) Can’t we hold it in the mind all at once—past, present, and future all in our possession? Vladimir Nabokov seemed to think that was the ideal of reading: to possess a book entire, in memory, rather than to encounter it in a state of ignorance or innocence, experiencing it page by page, word by word. “A good reader,” said Nabokov in his Lectures on Literature, “a major reader, an active and creative reader is a rereader.”

  And I shall tell you why. When we read a book for the first time the very process of laboriously moving our eyes from left to right, line after line, page after page, this complicated physical work upon the book, the very process of learning in space and time what the book is about, this stands between us and artistic appreciation.

  Ideally a book should be like a painting, which we comprehend (said Nabokov) all at once, outside of time. “When we look at a painting we do not have to move our eyes in a special way even if, as in a book, the picture contains elements of depth and development. The element of time does not really enter in a first contact of a painting.”

  But can a book really be comprehended whole, all at once, apart from time? Surely a painting is not absorbed in one fell swoop. The eyes roam, the viewer sees this and then that. As for books, they play with time, as music does. They thrive on anticipation, they flirt with expectation. Even if you know a book well—even if you can recite it entire, like the Homeric poet—you cannot experience it as a timeless object. You can appreciate its echoes of memory, its tricks of foreshadowing, but when you read a book you are a creature living in time. The novelist and translator Tim Parks points out the essential role of forgetting. “Nabokov does not mention forgetting,” he writes, “but it’s clear that this is what he is largely talking about.” Remember: Memory is not a tape recorder. Not “a stereotype or a tear-sheet.” Memories, as Parks says,

  are largely fabrications, re-workings, shifting narratives, simplifications, distortions, photos replacing faces, and so on; what’s more, there is no reason to suppose that the original impression is intact somewhere in our heads. We do not possess the past, even that of a few moments ago, and this is hardly a cause for regret, since to do so would severely obstruct our experience of the present.

  Also in play is the obverse of
forgetting, which is not-yet-knowing. Even the omniscient rereader remembers not-yet-knowing, or where’s the fun? No matter how many times we reread a book, we want ignorance of the past, doubt about the future, or we read without expectation, disappointment, suspense, surprise—the panoply of human emotions dependent upon time and forgetting. In Nabokov’s Ada, someone (the omniscient author or his forgetful narrator) says of his heroes, “Time tricked them, made one of them ask a remembered question, caused the other to give a forgotten answer.” They strive “to express something, which until expressed had only a twilight being (or even none at all—nothing but the illusion of the backward shadow of its imminent expression).” Time tricks us all, even fastidious rereaders with time machines.

  So even in a book, as in life, closure is an artifice. Someone needs to create it. It is the author who takes on God’s job, and as the narratological options grow more convoluted, so do the world-building challenges. “Writing is extremely difficult,” says José Saramago, “it is an enormous responsibility, you need only think of the exhausting work involved in setting out events in chronological order, first this one, then that, or, if considered more convenient to achieve the right effect, today’s event placed before yesterday’s episode, and other no less risky acrobatics, the past treated as if it were new, the present as a continuous process without any present or ending.” In turn, readers—and moviegoers—grow ever more aware, learning the tropes and the tricks. We stand on the shoulders of all the time travelers who came before.

  Here is a man with a time machine. Perhaps I should say a man in a time machine. His name is Charles Yu. He tells us he works in the time-travel industry. He repairs time machines for a living. He’s no scientist—just a technician. “To be more specific,” he says, “I am a certified network technician for T-Class personal-use chronogrammatical vehicles.” For now (troublesome word, in this book) he is living inside one: the TM-31 Recreational Time Travel Device,

  which features an applied temporalinguistics architecture allowing for free-form navigation within a rendered environment, such as, for instance, a story space and, in particular, a science fictional universe.

  In other words, we are in a book. It is a story space, a universe. “You get into it. You push some buttons. It takes you to other places, different times. Hit this switch for the past, pull up that lever for the future. You get out and hope the world has changed.” Yes, we know all about that by now. We can expect some paradoxes, too.

  Charles is a bit of a sad sack. His main companions are a computer UI with a personality skin named TAMMY (sexy software with self-esteem issues) and a “sort of” dog named Ed. The dog was “retconned out of some space western.” Retconning is a post-post-modern narratological term, short for retroactive continuity: after-the-fact rewriting the backstory of a fictional world. Ed doesn’t actually exist, though he has a strong smell and licks Charles’s face. “Ed is just this weird ontological entity….He must violate some kind of conservation law. Something from nothing: all this saliva.” Evidently we should just accept it. Charles does. It’s a lonely job: “A lot of people who work in time machine repair are secretly trying to write their novels.” Coincidentally, the book we are reading is a first novel by an author named Charles Yu, called How to Live Safely in a Science Fictional Universe.

  Living in a time machine gives Charles an unusual perspective. Sometimes he feels he exists in a tense: the Present-Indefinite. It’s a kind of limbo. It’s different from Now. “In any event, what do I need with Now? Now, I think, is overrated. Now hasn’t been working out so great for me.” Chronological living—everyone just moving forward, looking backward—is yesterday’s news. “A kind of lie. That’s why I don’t do it anymore.”

  So he sleeps alone, in “a quiet, nameless, dateless day…tucked into a hidden cul-de-sac of space-time,” and he feels safe there. He has his own mini-wormhole generator that he can use to spy on other universes. Sometimes he has to explain the facts of life to his customers, people who rent time machines in hopes of going back and changing history, or people who rent time machines but worry about inadvertently changing history: “Oh God, they say, what if I go back and a butterfly flaps its wings differently and this and that and world war and I never existed and so on and yeah.” The rules are that you can’t. People never want to hear it, but you can’t change the past.

  The universe just doesn’t put up with that. We aren’t important enough….There are too many factors, too many variables. Time isn’t an orderly stream. Time isn’t a placid lake recording each of our ripples. Time is viscous. Time is a massive flow. It is a self-healing substance, which is to say, almost everything will be lost.

  Charles has learned some more rules. If you ever see yourself coming out of a time machine, run the other way as fast as you can. Nothing good can come of meeting yourself. Try not to have sex with anyone who could possibly be a relative. (“One guy I know ended up as his own sister.”) This is twenty-first-century metanarrative: loopy, recursive, self-referential to the nth degree. Real science (“real” science) mixes with science-fictional science, which is both a parody of real science and a real science of science fiction. If you see what I mean. Example: “A character within a story, or even a narrator, has, in general, no way of knowing whether or not he is in the past tense narration of a story, or is instead in the present tense (or some other tensed state of affairs) and merely reflecting upon the past.”

  Above all he misses his father—the father who taught him everything about time travel, who used to say things like, “Today we will journey into Minkowski space,” whom he reveres and loves in his memory. So much of time travel is a search for parents, when you think about it. In the Back to the Future movies, Marty McFly needs to discover his parents’ pasts. His destiny is there. For that matter, the Terminator movies are all about finding (killing, protecting) the mother, though the characters don’t talk as much about their feelings. “Who wouldn’t want to travel back in time and encounter their parents before they become their parents?” asks William Boyd in his 2015 novel Sweet Caress. “Before ‘mother’ and ‘father’ turned them into figures of domestic myth.” We experience childhood one way when we’re living it and another way when we relive it in memory. And when we become parents ourselves, we may rediscover our own parents and our own childhoods, as if for the first time. That’s the closest we get to having a time machine.

  “How can we tell present from past?” Charles’s father says this is the key question of time travel. “How do we move the infinitesimal window of the present through the viewfinder at such a constant rate?” It may also be the key question of consciousness. How do we construct the self? Can there be memory without consciousness? Obviously not. Or obviously. It depends what you mean by memory. A rat learns to run a maze—does it remember the maze? If memory is the perpetuation of information, then the least conscious of organisms possess it. So do computers, whose memory we measure in bytes. So does a gravestone. But if memory is the action of recollection, the act of remembrance, then it implies an ability to hold in the mind two constructs, one representing the present and another representing the past, and to compare them, one against the other. How did we learn to distinguish memory from experience? When something misfires and we experience the present as if it were a memory, we call that déjà vu. Considering déjà vu—an illusion or pathology—we might marvel at the ordinary business of remembering.

  Can there be consciousness without memory? “We are our memory,” said Borges,

  we are that chimerical museum of shifting shapes,

  that pile of broken mirrors.

  Our conscious brains invent the concept of time over and over again, inferring it from memory and extrapolating from change. And time is indispensable to our awareness of self. Just as an author does, we construct our own narrative, assemble the scenes in a plausible order, make inferences about cause and effect. Charles’s software companion explains, “The book, just like the concept of the ‘present,
’ is a fiction. Which isn’t to say it’s not real. It’s as real as anything else in this science-fictional universe. As real as you are. It’s a staircase in a house built by the construction firm of Escher and Sons.”

  You order the slices of your life. You edit the film even as it records. “Your brain has to trick itself to live in time,” she says. Time travel adds a high-octane upgrade to the usual process of creating consciousness.

  —

  A HUNDRED YEARS EARLIER, when storytelling seemed simpler and E. M. Forster thought every novel embodied a clock, he invented a story about the future. “Imagine, if you can,” he wrote in 1909, “a small room, hexagonal in shape.” At its center rests an armchair. In the armchair sits a woman—“a swaddled lump of flesh…with a face as white as a fungus.” She is happily incarcerated, with every modern comfort:

  There were buttons and switches everywhere—buttons to call for food, for music, for clothing. There was the hot-bath button, by pressure of which a basin of (imitation) marble rose out of the floor, filled to the brim with a warm deodorized liquid. There was the cold-bath button. There was the button that produced literature, and there were of course the buttons by which she communicated with her friends. The room, though it contained nothing, was in touch with all that she cared for in the world.