Soul of the World (18 page)

The idea of wormholes has continued to fascinate scientists. Might wormholes someday be tamed? Might starships use them? Igor Novikov thought so, and he even went further. In his book
The River of Time
, Novikov speculates that at some point in the future it might be possible to build two huge gravitational fields that would create a wormhole between them. Why would we want to do this? Because, Novikov claims, a wormhole, after a bit of ingenious tinkering, could be turned into a time machine. And then he conjectures that there might be an even easier way to capture a wormhole, and it’s right under our noses.

According to recent cosmological theories, our four-dimensional space-time universe is not what it appears to be. Apparently it has many other dimensions “curled up” inside the “quantum foam” (sub-atomic space-time) that underlies all matter. These are failed dimensions that, unlike the other four dimensions, didn’t unfurl after the Big Bang. They survived, invisibly locked within matter throughout the universe, suppressed by the dominant dimensions of classical space-time. Like dimensional viruses suppressed by a cosmic immune system, they are
biding their time until something or someone unlocks their potential. As well as holding these potential new dimensions, the matrix of the “quantum foam” contains some other surprises—tiny black holes. And wormholes.

Cosmic engineers could pluck a wormhole out of the quantum foam in our own backyard. In 1988, in a paper published by Michael Morris, Kip Thorne and Ulvi Yurtsever, the authors wrote, “One can imagine an advanced civilization pulling such a wormhole out of the quantum foam and enlarging it to classical size.” Then, as Novikov blithely suggests, the wormhole could be stabilized and towed towards a large gravitational body, like a neutron star. (Attaching grappling hooks to such a will-o’-the-wisp would be one of the minor problems, no doubt.) Novikov would then park the wormhole vertically over the neutron star. One mouth of the wormhole would be lowered till it almost touched the surface, while the other would be raised hundreds of miles above the star.

Here’s the clincher. Because gravity affects time—passing more slowly near the surface of a large planet and more quickly away from it—Novikov argues that eventually the two mouths of the tunnel would get out of synch. The greater the gravity and the longer the wormhole was left to develop its time differential, the greater the difference in time between one mouth and the other. Eventually, when enough of a temporal disparity had developed, Novikov proposes that the wormhole be dragged away and parked in an empty region of space. If the time difference between the two mouths was, say, two days, then as soon as the wormhole was parked, someone entering the mouth leading to the past would be transported two days backwards in time.

The main limitation to the idea of wormhole time travel is that you could never travel farther back in time than the date at which the wormhole started to operate. Sadly, visits to the Jurassic era would be
out of the question. But Stephen Hawking’s tourists from the future might well become a reality. In fact, I suspect that as soon as the wormhole was parked, maybe even before, tourists and who knows what else would begin to emerge from it. After all, the scientists of the future would have a leg up on the scientists who built the wormhole. They’d be able to look back over years of observations of the behaviour of the wormhole. Perhaps they would find ways of tweaking its performance, of extending its temporal range. The point is, the normal causal relationship between the building of knowledge over time from experience and observation could be inverted in a second. Cronos would be stymied.

This brings us back to our paradoxes. What if a mischievous scientist from the future were to explain a Nobel Prize–winning technology to a scientist from an earlier age and the earlier-age scientist went on to win the prize? From the perspective of the future scientist, with access to history books, she knew that the earlier scientist was going to invent this technology anyway, but she short-circuited the process. She might not have been changing history, but she was subverting it. Both scientists would rely on future history being fed back into the past without any causality. Talk about intellectual property. And what if the scientist from the future gave the idea to someone else, and he or she got the Nobel Prize instead, altering history as in the grandmother paradox? Perhaps, as Novikov and some other physicists believe, none of these events could occur; something would always intervene to ensure that the law of causality would never be contravened retroactively. But there are other problems with time travel.

R
IGHT
T
IME
, W
RONG
P
LACE

The intimate relationship between time and space is something that rarely occurs to novelists and filmmakers dealing with time travel. In H. G. Wells’
The Time Machine
, the world transforms around the protagonist while he remains stationary. If you think about it, though, time is also place. The co-ordinates of a specific time—say, Italy during the reign of Augustus—always include a place. But the fact that place and time are so inextricably connected presents an even more complicated problem for a time machine like the one Wells imagined.

Let’s say you have built the first time machine, something the size of a phone booth. Because it’s a prototype, it has a very limited range—something like twenty-four hours. Imagine that on a Wednesday afternoon, October 6 at 4:00 p.m., you decide to test your time machine for the first time. You step into the machine, strap on your harness and seat belt, make sure the airtight seals around the door are locked, and set the dials for 4:00 p.m. the day before: October 5. Then you cross your fingers, activate the chronological drive and
wham
—suddenly you’re floating in space. The laboratory is gone, the city is gone, and the earth is gone. You look at the master clock in your time machine and, indeed, it does register 4:00 p.m. on October 5. But where is the earth?

Looking out of your time machine window (which, fortunately, you had the foresight to make airtight and pressurized in case of an emergency), you can see a blue-green planet about nine thousand kilometres away. Being a fairly savvy scientist, you realize that that planet is earth, and somehow you’ve missed your rendezvous with your laboratory. Earth, for some reason, is very far away. What happened?

There isn’t much air in the time machine so you have to think quickly. Then, suddenly, you’re hit with the terrible certainty that
you’ve been a complete
dummkopf.
“Of course!” you exclaim out loud, “Why didn’t I think of that?” What you’ve realized is that the earth moves in its orbit around the sun at 108,000 kilometres an hour, that our sun orbits the galactic centre at a speed of 792,000 kilometres per hour, and that our galaxy is moving relative to our local group of galaxies at about the same speed. Because time is also place, where you or your planet were a moment ago in the past is not where you or the planet are now. You and your time machine have hit the right time but the wrong place. Earth on October 5 was nowhere near where it was on October 6.

The old cliché about “spaceship earth” is quite correct—earth is moving faster than any rocket, though we don’t get much of a sense of that speed when we’re sitting in a comfortable chair reading a book, or strolling home from dinner at a local restaurant. The cliché should be changed to “timeship earth.” Even if a time machine only went five minutes into the past, it would still simply disappear, not only because in our present time we couldn’t see it, but because it would reappear five minutes back in time at that point in outer space, hundreds of kilometres away, where the earth had been five minutes earlier.

But is that really true? Perhaps I’m being naive. Although the jury is still out, there are some physicists who insist that special relativity compensates for the spatial difference. Here is where the counterintuitive weirdness of Einstein’s theory reveals itself again, both to confound classic Newtonian physics and to save H. G. Wells’ time machine from flying into space like the time machine in my example. According to some interpretations of special relativity, a time machine that follows a continuous timeline into the past or future will automatically travel through space as well. There’s no need to worry about co-ordinates in three dimensions as long as you’re on the timeline, which will always follow the curves of space-time.

T
IME
T
RAVEL BY
S
TOPPING IN
T
IME

What about a time machine that could idle, say, in a sort of temporal neutral gear—not quite in the present or the past or even the future—and stand still, motionless against the flow of time like a rock in a river, but more as if it were outside the dimension of time? I suppose that if you were able to stop, to let time flow past you, then the future would unfold around and ahead of you while you remained in stasis. Perhaps you would stay in one place, like a fixed date on the calendar, and sink into the past as the present moved increasingly ahead of you. Or if your time machine were just very slightly out of synchronicity with the flow of time, such a journey wouldn’t be all that much different from what we already experience. Maybe you would take on a golden hue, like gold, or glow with the blue aura of Cherenkov radiation.

Are we not all like time machines of identity, moving forward into the future at the constant rate of time’s passage? We pace time itself—“one second per second,” as the scientists describe it. And we travel backwards too, at least in our memories. Deep sleep is a kind of time machine, though it only works for short hauls into the future. If people could be put into suspended animation, then the sleep effect of time contraction would be even more pronounced. If not exactly time travel in the orthodox sense, for someone revived after a century of suspension it might as well be.

Culturally we have been enthralled by the idea of time travel since H. G. Wells’ groundbreaking
The Time Machine.
Other splendid novels such as Daphne du Maurier’s hallucinogenic
The House on the Strand
, Jack Finney’s
Time and Again
and J. K. Rowling’s
Harry Potter and the Prisoner of Azkaban
have all dealt with the subject. As have hundreds of short stories, films and television movies.

When I was fifteen my favourite television show was a time-travel series called
The Time Tunnel.
It aired, disappointingly, for only one season. The tunnel of the title was housed in a top-secret underground facility in the desert. There were no signs to mark its presence, no fences, only a road with an invisible gate that hinged the whole road downwards. Visitors drove down the ramp into an underground passage that led to the high-tech complex in which the time machine was housed. Behind them the road hinged up again, leaving no sign of the entrance.

The time machine itself was a tunnel whose black-and-white striped walls spun like an op-art whirlpool when the machine was turned on. The time travellers would simply walk into the tunnel and disappear, reappearing at their chosen destination in time. In retrospect I wonder if the whirlpool shape of the machine wasn’t influenced by Wheeler’s wormhole theory. If so, then the
The Time Tunnel
was the first visual representation of a wormhole in science fiction.

The Time Tunnel’s
main characters were two brave young men who had various adventures depending on their destination in time. By the end of the show’s run, probably due to budgetary constraints, the protagonists ended up doing most of their time-travelling to the American Wild West of the nineteenth century. I suppose western sets were cheaper to lease. Very rarely did they go farther back in time or into the future, and eventually the show degenerated into a western.

At least the 1985 film
Back to the Future
had a sense of humour about time travel, especially in the appearance of the time machine itself: the souped-up De Lorean sports car. The most dramatic part of the film (borrowed from the 1984 film
The Adventures of Buckaroo Banzai
) was how the car/time machine travelled through time. The De Lorean had to race towards a brick wall or some other solid, immovable object and hope that it achieved the correct velocity to make the time-jump before it crashed. There’s something whimsical and yet accurate about this—the
future, like an impervious wall, is an opaque barrier into which we cannot see, so we race headlong in the hope that we will penetrate it.

C
AR AS
T
IME
M
ACHINE

Though not a modified De Lorean, my car, like all cars, is a time machine of sorts. This morning I was late for a dental appointment, so I used the car to gain time lost while I read a letter and watered the newly planted grass in front of my house. I drove three blocks south, then turned east on Davenport Road (the old Huron trail being the fastest route downtown). I went above the speed limit to make up for lost time, taking the risk that I wouldn’t lose more time by being pulled over.

As I sped through the traffic, it struck me that my vehicle is a nexus of time. The glistening, lubricated metal shafts turning within sleeves of steel, and the engine itself, smoothly exploding bursts of incandescent gases in a controlled, industrial rage, are technologies that have remained unchanged since the nineteenth century. The electrical system that insinuates itself throughout the car, and is its nervous system, is from the twentieth century. And the gasoline that powers everything represents an even longer economy of time, oil deposits being the liquefied organic remains of plants and animals that are millions of years old. My pistons are fired by ancient sunlight, gathered by living matter, stored for eons in geological darkness and then exploded briefly into light again, though within another darkness—the mechanical midnight of the car’s engine.

Then there’s the final layer of time: the skin of fashion. My car is five years old, and its chassis represents an era of automotive styling that is almost passé. Not yet a living fossil, it is nevertheless a part of cultural history—an aesthetic time capsule from a previous decade. All of these
factors—the concatenation of motion, history, prehistory and recent past—have interwoven so many layers of time within my car that it is, if not exactly a time machine, then a machine filled with time.