Soul of the World (17 page)

With that idea in mind, Penzias and Wilson went back to their antennae and began to evaluate the consistency of the noise in all directions. It was identical everywhere, and it was clearly from a source beyond our own galaxy. After further analysis they realized, with mounting excitement, that they were eavesdropping on the birth of the universe itself. What was causing the background static was the primordial radiation left over from the Big Bang, like the sound of a bell that was still ringing, faintly, 13.7 billion years after being struck loudly at the very beginning of time. The irksome “noise” they had stumbled upon won them the Nobel Prize.

T
HE
B
IRTH OF
T
IME

After looking at the evidence that Hubble and Penzias and Wilson presented, physicists concurred that time commenced at the beginning of the universe. They also concluded that there couldn’t have been a “time before” the Big Bang. It turned out that the relationship between matter, energy and time in our universe is intimate—time came into being alongside the other dimensions. Here you might ask, “How could the universe have arisen from nothing? How could there
not
be a time before time?” These aren’t naive questions. For hundreds of years, philosophers have struggled with them. In the late eighteenth century, Immanuel Kant decided that the birth of the universe must be a paradox, for how could anything arise out of nothingness? Nothingness, he said, couldn’t create “a condition of being, in preference to that of
non-being.” In short, Kant came up against the modern reality—the universe is impossible and finite. St. Augustine also thought about the beginning of the universe, though he was closer to the modern scientific view. Linking time to its inception, he wrote, “The world was made, not in time, but simultaneously with time.”

A helpful way to wrap your mind around what didn’t come before the universe—the non-time before time began—is to think of it as identical to the period before you were born. At one point you didn’t exist; then you did. The universe is like that, only without a parent. The nothingness that birthed our universe is so absolute that even death, the annihilation of a living being for all eternity, would be as life compared to it. This is what lies at the beginning and (as we will see) the end of the universe.

Okay, you might say, given the inconceivable absence of anything before the first moment of time, wouldn’t there still have to be a
first moment
, a start to all of this? Science says no; the universe came out of less than nothing and had no first moment. Ask yourself if there is a final, smallest number that is just slightly, infinitesimally larger than zero. Try to find some number where you can stop and say, “There, that’s the last number before zero.” It can’t be done. You can always keep halving a smaller number out of the previous until you meet infinity (or eternity, however you wish to look at it). Just as there is no final number, there is no first moment.

How, then, did moments themselves begin? And how did something come from nothing? This is where quantum physics comes to the rescue. At the level of quantum phenomena, which is a very strange and counterintuitive world, particles like electrons can pop into existence within the pure vacuum of interstellar space billions of miles from any stars. They literally appear out of nowhere, and it is this magic propensity that provides a clue as to how our universe began. Out of less than
nothing,
within
less than nothing, where there was no time, no space, no matter, no “was,” an infinitesimal blip switched on and the unimaginable occurred—a universe exploded into being simultaneously with the only element that could keep it expanding: time.

Yet according to physicists, even the presence of time itself was a bit of a fluke. They’ve modelled many other possible universes that could have arisen from a big bang—parallel universes where physics are slightly altered—and have found that some of them might even have formed without time. So we’re lucky. As Paul Davies wrote in
About Time: Einstein’s Unfinished Revolution
, “For reasons we know not, the quantum state of our universe, fortunately,
is
one of those very special states that permits time to emerge from this primordial jumble, as the universe evolves’ away from the Big Bang, in a fuzzy and ill-defined way. And that is good news, because life in a universe without any sort of time would be difficult.”

Now, 13.7 billion years after it began, time continues unabated. The present may be a vanishing threshold forever sliding into the future, but it has the entire history of the universe behind it, substantiating it. The past is the absent miracle that shores up the present. We are constituted by our history. Without the products of the past, without everything that history and prehistory has built—the mountains, the stars, the planets, the oceans and ourselves—the present would exist only as an abstraction within a vacuum, an airless, colourless trace moving like a solitary tsunami through an empty ocean of time. And we, without memory and past, would be vacant ghosts.

With the present being an impossibly small, possibly immeasurable fraction of time, time is almost 100 percent history. Time is almost entirely what was. But here’s the kicker: what
was
doesn’t really exist, except in our memories and the solid objects it has produced. And even they, in the end, will succumb to deep time, as the universe continues
its evolution. Ultimately, when the fabric of the universe begins to unravel, when the atomic bonds that hold solid matter together break down after trillions of years, when even diamonds begin to dissolve (turning first into smooth spheres and then disappearing entirely), the emptiness of the past will become destiny.

T
HINGS
Y
OU
C
AN
’
T
T
AKE
B
ACK

The past is only the present become invisible and mute; and because it is invisible and mute, its memoried glances and its murmurs are infinitely precious. We are tomorrow’s past.

—
Mary Webb

September is almost over. Summer ended officially six days ago, on the twenty-second, and last night there was a frost warning. I put plastic over my basil plants and the big palm to protect them, though this morning there was no frost on the grass. Still, the banana leaves are looking a bit spotty, and while the flowers on my mandevilla are going strong, the leaves look a little lacklustre. It’s a poignant season for someone who loves summer as much as I do. The celebration’s over, the guests are leaving. This week alone I’ve seen two noisy V’s of southbound geese. When I was mowing the grass a couple of days ago, I found a wine cork from my dinner party, part of the dwindling evidence of that marvellous night with my friends. The stopper from a time capsule whose opening is now in the past.

In one sense the past is very close to us. It is the perpetually open back door of “now.” The present, in some entangled and complex way, is wrapped around the immediate past, and yet, at the same time, the
past is always missing from it. The past just isn’t there. Elusive, intangible, always pacing the present, it’s one step behind; as soon as we turn to grasp it, it’s gone, so that something that happened a second ago might as well have happened a hundred years ago for all that we can do about it. It is equally insubstantial, equally lost. This was a truth that was brought home to me, in a small but irritating way, last Friday afternoon when I locked my keys in the car.

It was rush hour and I had parked illegally in order to use a bank machine. The traffic was so heavy that I was trapped in my car at first and had to wait for a gap between cars before stepping out. As soon as I shut the door behind me, I realized that I’d left the keys in the ignition with the engine running. My mistake, a brief slip, was already part of the past. I couldn’t take it back. Waiting for the towing company to come and break into the car, I thought of other moments where the instant division between present and past is equally irrevocable—transitory moments where the merciless past bares its teeth and holds on like a bull terrier.

I came up with the Waterford goblet knocked by an errant elbow from a counter above a marble floor; the cartoon character Wile E. Coyote lingering in the air after sliding off the top of a high mesa; the policeman’s flashing light in your rear-view mirror; and the last glimpse of your house keys as they tumble down a sewer grate during a downpour. Driving home after the tow-truck operator rescued me, I thought of the past as the stone-faced customs agent who impounds your lip gloss or your butane lighter at the airport—you cannot argue with the past. There is no bartering, no deal-making. The past is absolutely bureaucratic.

Tonight, in my study, I can feel again the adamantine implacability of the past as I felt it this afternoon. The past is like a ubiquitous central vacuum that punctuates the entire universe with a micro-fabric of
temporal black holes—a three-dimensional quantum sieve of suck. It’s like a big drain, a funnel. Everything that falls into it is immediately carried away. You can say “now,” and then you can say “now” again, but both “nows” are immediately in the past.

When I pay close attention to the rushing divide between the present and the past, if I concentrate on that precise boundary where the universe and everything in it pour over the edge of “now” into the abyss of history, I imagine that I can sense it. The past is all around me, separated from me by an instant—the waft of a butterfly’s wing, a slip of gauze. But it’s my sense of hearing that somehow captures the present slipping into the past. When I listen closely enough, every sound—a ticking clock, the rustling of papers—seems to emit a faint, almost undetectable resonance as it slips into the immensity of the past. It’s a sound beyond normal hearing, more like a studio sound effect than anything natural, and I’m far from sure that I hear it at all.

Perhaps this low-level, almost indistinguishable echo is like the “Hawking radiation” that leaks out of black holes. Not everything falls into black holes. At the edge of a black hole there is a barely detectable fizz of quantum particles that, because they are so light—almost massless—escapes its monstrous gravity. This outward escape of quantum particles is called Hawking radiation, after Stephen Hawking, who discovered it. It has great consequences for the future of the universe because it means that, after billions of years, black holes will simply evaporate, drained to nothing by the infinitesimal, but steady, loss of mass. This is a great contradiction of a law of physics called the Conservation of Information. According to that principle, all information contained in the universe has to be conserved, retained, even if transformed. The information in a piece of wood is contained in the
molecular lattice of its cellulose. If the wood burns, the cellulose is converted into light, heat and carbon; nothing is lost. But if all the information that gets sucked into a black hole merely evaporates over time, then black holes represent a monstrous type of ultimate, cosmic death: the death of matter (and all the information contained in matter) itself. A past where even the past is annihilated.

I am afraid I cannot convey the peculiar sensations of time travelling. They are excessively unpleasant.

—
H. G. Wells
, The Time Machine

A little over two blocks south of my house, there is a low escarpment, about five or six storeys tall, that snakes several miles through the city. In aerial photographs the cliff looks almost like a river as it meanders from east to west across the grid of city blocks. One of the first and oldest streets in Toronto, Davenport Road, runs along its base. Houses on the north side of the street are angled into the bank so that their back doors exit on the third floor. According to historical records, Davenport Road follows the path of an old trail used by natives for thousands of years. Before that the trail could only have been used by fish, because 11,200 years ago, at the end of the Wisconsinian glaciation, it was under water.

The escarpment is the old shoreline of an extinct glacial lake, Lake Iroquois, that was twice the size of present-day Lake Ontario. Were a catastrophic flood to resurrect Lake Iroquois, my house would be safe, but most of the city, at least the part south of the old shoreline, would be submerged. Only a few of the taller office towers in the financial district would poke through. If my house could be transported eleven thousand years back in time, then on windy nights I would be able to
hear waves crashing on the shore as they did when the glaciers had begun their last retreat.

My morning jogs have been glorious this week. The October leaves, like solar prisms, seem to be replaying all the sunny afternoons they soaked up during the summer. Every kind specializes in a different part of the summer spectrum—maples flame red and orange, the ash trees glow with deep, moody yellows, while the sumac thickets distill the fluorescent pink of a hundred sunsets. My jogging path takes me through a park perched on the edge of the Davenport escarpment. On clear, still days, I can see across Lake Ontario to the United States. For several mornings recently, when I’ve looked southwest, I’ve been able to see the mist from Niagara Falls, seventy kilometres away. It’s a faint puff of what looks like smoke or steam, tethered to the horizon like an unmoving cloud.

The Niagara River tumbles over a limestone escarpment much higher than the earthen one that runs along the southern edge of my neighbourhood. At ninety metres tall and hundreds of kilometres long, it’s one of the major landforms of the region. It extends in a great arc from Green Bay, Wisconsin, through upper Michigan into central Ontario, then down the Bruce Peninsula and through Niagara, finally petering out in upstate New York. As my father once did, I’ve learned to see landscapes in geological time-lapse, and the Niagara Escarpment has an extraordinary, almost cataclysmic, geological pedigree.

Because the continents float on a sea of molten magma, the land mass that now makes up Michigan and southern Ontario was once very far from where it is now. Six hundred million years ago, it was parked just south of the equator and covered with a tropical sea not unlike today’s Caribbean Sea. But deep beneath the continental crust, a storm was brewing. A convection current launched from the centre of the earth began to spin the magma directly under this sea into a giant vortex. Like a cataclysmic version of Edgar Allen Poe’s maelstrom,
the magma whirlpool deepened and widened, drawing the rocky crust above down into it (imagine a thin film of plastic covering the vortex of a drain). Except that this was no transient event: the whirlpool lasted for millions of years. Eventually it created a bowl-shaped depression in the earth’s crust that was overlaid with limestone deposits.

At its greatest extent, the lava vortex was eight hundred kilometres across, and it exerted its downward pull for three hundred million years. Then, mysteriously, it stopped. Afterwards, in a geothermal rebound, the bowl-shaped deposits began to rise for an additional two hundred million years. Finally the whole process ended.

The continent, with its slightly elevated limestone bowl, continued to drift northwards, and over millions of years the layers of limestone that formed the edge of the bowl eroded. Because they were canted up at a shallow angle, and because the top layer of limestone was composed of hard dolomite, a cliff face emerged over eons. At the time of the dinosaurs it was barely high enough to trip a baby
Tyrannosaurus rex
, but by the beginning of the ice age a million years ago, the escarpment was tall enough to make continental glaciers stumble.

“Time will tell,” as the saying goes. It will, indeed. Geological time-lapse tells us truths that were once unimaginable. Everything around us, even the seemingly unmoving rock beneath our feet, is in transition. It is when we time-travel in our minds, animating inert landscapes, that the drama of life speaks to us.

A S
EASONAL
T
IME
M
ACHINE

When I was a child, every July and August resurrected for me the primeval, eternal summer of the age of reptiles. Snakes basked in the sun on forest paths near my home, and lizards with bright blue tails slipped
through the ferns. In the pond, giant, antediluvian snapping turtles lurked. I was ten years old when I imagined that the seasons were like a Grand Canyon of time, that the journey from March to November took me through the same nine hundred million years as the geological journey from bottom to top of the world’s deepest canyon.

Everything began on March 21. This was the first day of spring and, according to my dual calendar, the beginning of the Neoproterozoic eon. Here, at the dawn of life, the first unicellular animals arose. The pond was mostly clear of ice, and tiny, single-celled organisms proliferated invisibly in the shallows. I knew about them because the year before I had taken home a sample of pond water, put it under my brother’s microscope and seen sleek, transparent creatures that used whips and moving bristles to propel themselves.

April was the beginning of the Paleozoic era, when the first crustaceans and fish began to stir in the ancient oceans. On bright, warm afternoons, schools of wild goldfish sunned themselves near the surface of the pond, and at night, in the shallows, the eyes of crayfish glowed like twin embers in the beam from my flashlight. Plants colonized the land during the Paleozoic, and, right on schedule, the first green shoots of wildflowers stuck up through the leaf litter in the woods.

Amphibians entered the scene during the Carboniferous period—in late April and early May by my calendar. The frogs began their mating trills, and I could hear them through my bedroom window on the first warm nights of May. The fiddleheads emerging in early May evoked the giant tree ferns of the late Carboniferous. By June tadpoles were wriggling by the hundreds in the pond, and even they obeyed the evolutionary edict of my geological calendar: they grew legs and dropped their tails in late June, transforming from aquatic to land animals. Amphibians gradually evolved into dinosaurs, and summer became the age of reptiles—July the Jurassic, August the Cretaceous.

Autumn, naturally, became the Cenozoic era, the age of mammals. The fat squirrels that buried walnuts in our backyard were glossy, and the neighbourhood cats looked sleeker and quicker as they stalked migratory birds in the hedges. All mammals seemed invigorated by the fall weather. Within the Cenozoic era, the late Tertiary period marked the height of the age of mammals. Some of these extinct behemoths reached extraordinary sizes, larger than elephants. The giant megathurium of South America, a kind of sloth, stood twenty feet tall. The glyptodon, from the armadillo family, was the size of an armoured vehicle. But global conditions were starting to cool. November and December brought the age of the glaciers, and then our own period of history, the Quaternary. During the first snowfalls in late November, I imagined herds of woolly mammoths gathering in the frosty gloom at the foot of glaciers.

Winter ended the yearly cycle, bracketing the beginning and the end of the journey of life through time, just as it did in prehistory seven hundred million years ago, when a glacial age almost ended the beginning of life on earth. This glacial age was apocalyptic; compared to it, later glacial ages were more like spring thaws. Simple multicellular organisms had barely gotten a foothold when glaciers spread out from the poles, just as they did only a few thousand years ago, but they didn’t stop. They continued southwards until they covered the entire planet. All the oceans froze, capped with a kilometre-thick icy layer. If there had been intelligent life on Mars at that time, scientists there would never have bothered sending a rover to look for life on earth. Earth, as seen through their telescopes, would have been a brilliant white sphere, a barren planet that had been locked in a deep-freeze for millions of years.

And yet, life, hardly given the warmest of welcomes, survived. Bacteria, algae and prokaryotic organisms living near geothermal deepsea vents and in hot springs, continued to exist for millions of years
until, finally, in a great thaw, the icy clutch of winter was broken. After that cosmic spring, life was reanimated in a renaissance that eventually changed the face of the earth. On my time-travel calendar, March 21 is like all the annual holidays rolled into one. It is nothing less than the celebration of the tenacity of life and its endurance over time. Now, in us, life can look back at its beginnings. If life was matter’s dream, then consciousness was life’s dream. It was only a matter of time.

T
IME
M
ACHINES AND
W
ORMHOLES

If you haven’t found something strange during the day it hasn’t been much of a day.

—
John Wheeler, physicist

Don’t let anyone tell you there’s no such thing as a time machine. I’ve seen one. It’s the size of small city and it sits beside the Bay of Naples, in Italy. A few years ago, when I stepped through the northern gate of Pompeii, I stepped two thousand years back in time.

What astonished me was that Pompeii didn’t look old—far from it. It was a surprisingly modern city, lacking only the voices of its citizens, the rasp of metal-clad wheels on cobblestone, and barking dogs. The architecture was elegant and sophisticated. The city blocks, or
insulae
, as the Romans called them, were laid out in grids identical to any North American city. And they had plumbing! Aside from electric light and internal combustion engines, Pompeii lacked nothing. At one point I lost track of the other tourists and spent at least half an hour alone, wandering through the streets, peering through the gates of marbleclad villas or investigating corner wine bars that looked as if their patrons had just gone down the street to watch some civic spectacle.

Even Vesuvius, the volcano that both destroyed and preserved Pompeii, still looms in the distance, a plume of smoke issuing from its peak. I couldn’t get over the immediacy of the place; I became giddy with the sense of time travel. Later, after glutting my vision with impluviums, atriums, columns and statuary, I went to the train station and ate a grilled eggplant and cheese panini at a small café next door. It was there that I realized I had a feeling like jet lag, only this jet lag wasn’t from crossing a time zone or two—it was from being transported through millennia. Perhaps, in my own way, I had experienced the same delirium that H. G. Wells’ time traveller described.

Curiously enough, science doesn’t rule out the idea of time travel, especially into the future. In fact, the theory of relativity predicts it; if an object can attain speeds even half the speed of light, it will experience time warp. (As we know from our twin sisters, the twin who travelled into space and reached a high enough velocity returned to earth in the future.) But the notion of travelling backwards in time faces the seemingly insurmountable obstacle of time paradoxes, including the famous “grandmother paradox,” which says that if you go back in time and murder your grandmother, you will never be born. This and other paradoxes, in and of themselves, seem to completely rule out time travel, and yet some contemporary physicists have neatly sidestepped them. Dr. Igor Dmitrievich Novikov, professor of astrophysics at Copenhagen University, has come up with an eponymous self-consistency principle asserting that a time traveller will never be able to create paradoxes because her actions in the past will be “over constrained” by the laws of space-time. Novikov believes that a time traveller would be prevented from murdering her grandmother, even if she made every effort to, by coincidental events that would always intercede.

Others, like Stephen Hawking, still believe that time travel to the past is not possible, given what we now know. Hawking has written a “chronology protection hypothesis” in which he argues that nature will always prevent travel into the past, much like the conservation of energy prevents energy from disappearing. Also, he points out, somewhat tongue-in-cheek, that we would already know if time travel into the past will be discovered in the future because we “have not been invaded by hordes of tourists from the future.” Yet even Hawking does not absolutely rule out time travel to the past, and other physicists are even more enthusiastic about the possibility.

The American physicist John Wheeler had always been fascinated by Einstein’s theory of relativity. Even when his academic career at Princeton was interrupted by his participation in the Manhattan Project and Project Matterhorn B (the building of the atomic and hydrogen bombs respectively), he kept a corner of his mind busy tinkering with extensions to Einstein’s formulae. When he returned to Princeton to teach full-time in the mid-1950s, he was able to devote much more speculative time to these ideas. Wheeler was particularly interested in the curvature of space-time, and in 1957 he realized that under special gravitational conditions, the structure of space might be able to form a passageway—a kind of shortcut—between two disparate regions. He called this passageway a “wormhole.” Space-time physics hasn’t been the same since.

Many of his colleagues scoffed at his theory, saying his wormholes contradicted some of the basic laws of physics. They cited Einstein and pointed out that wormholes were impossible because of the intimate relation between space and time. After all, they insisted, if the “shortcut” were long enough, it could conceivably permit faster-than-light travel,
which was clearly an impossibility. But as the years went on, Wheeler’s math held up. Yet wormholes remained a theoretical possibility only until the ultimate discovery of “black holes” (a name Wheeler coined as well) a little over a decade later. Black holes were mesmerizing for physicists, particularly when it came to how gravity and light behaved around them. Here all bets were off, at least as far as the laws of conventional physics went. Physicists soon recognized that because black holes bent space-time so radically, they could themselves be the entrances to wormholes connecting distant regions of space. But black holes annihilate everything that falls into them, and, even if they were an entrance to a wormhole, where would the exit be—a billion miles away? Or in some unthinkable, parallel universe?