Trespassing on Einstein's Lawn (15 page)

As I gorged on all things QCD I learned that, as Rafelski had said, it's the vacuum that forces the quarks into confined living. From quantum uncertainty in the gluon field, virtual gluons emerge. But the thing about gluons—even virtual ones—is that they carry a charge. A gluon's job is to transmit a sticky force—the so-called strong force—to quarks.
The gluon recognizes a quark by its color charge. Photons act in much the same way, transmitting the electromagnetic force between electrons, which they spot by their electric charge. But whereas photons carry no electric charge of their own, gluons have color charge—so in addition to interacting with quarks, they also interact with themselves and with other gluons. As they boil up from the vacuum, the virtual gluons stick to one another, twisting and contorting into complex structures—structures that wall in the quarks, making it impossible for them to move freely through the vacuum. Stuck in a gnarled sea of virtual gluons, the quarks huddle together—red, blue, and green—their neutral charge protecting them from the dangerously sticky gluons. Imprisoned in triplicate, they form protons and neutrons—the massive cores of atoms. If it weren't for the structure of the vacuum, atoms would fall apart.

The force of the virtual gluon field restrains the quarks' movement; if you tried to grab one and move it, it wouldn't budge. As if it were
heavy.
In that way, the vacuum's virtual gluon field endows quarks with 95 percent of their mass, which in turn gives protons and neutrons their mass, which in turn gives atoms 99 percent of
their
mass … all of which means that the mass of everything around us, including our own bodies, is little more than the weight of the vacuum. The material world is nothing incarnate. Lucretius had said that “nothing can be made out of nothing.” Quantum chromodynamics begged to differ.

To set the quarks free, you have to dissolve the vacuum's virtual gluon structures. Look to higher temperatures and energies, inching ever closer to the conditions of the big bang, and the vacuum's structure melts away. As its convoluted forms dissolve, it begins to look more and more like nothing. Smooth and simple. Undifferentiated. Symmetric.

If there was one thing to know about symmetry, I learned, it's that it tends to break. As all the books explained, a pencil balanced on its tip has perfect rotational symmetry—it looks the same from every angle, 360 degrees around. It's also about to fall. Even though the pencil is in a kind of equilibrium state, it's not going to last, because there exists a state of even lower energy: the state in which it's horizontal.
The slightest breeze is going to knock that pencil over. And even though it has an equal chance of falling at any angle around the circle, it chooses only one. When it lands, rotational symmetry is broken.

One way to get symmetries to break is to turn down the temperature. A puddle of water is highly symmetric—look at it from any angle and it looks the same. But cool it down enough and it freezes, forming ice crystals with more structure and less symmetry.

Physicists, I learned, think about the universe the same way. In the heat of the big bang, the vacuum is symmetric. As the universe expands and cools, structure freezes in, like the twisted forms of virtual gluons. With structure comes mass. With mass comes everything else. The world we see around us and the people we see in mirrors are nothing more than broken shards of symmetry. Shards of
nothing.

I picked up the book
Longing for the Harmonies
by Frank Wilczek, who had won a Nobel Prize for helping to formulate QCD. He explained that spontaneous symmetry breaking occurs whenever there are an infinite number of equally valid vacuum states for a single, unique higher-energy state—like the continuum of possible positions in which the single pencil can land.

“The most symmetric
f
phase of the universe generally turns out to be unstable,” he wrote. “One can speculate that the universe began in the most symmetric state possible and that in such a state no matter existed: the universe was a very empty vacuum, devoid both of particles and of background fields. A second state of lower energy is available, however, in which background fields permeate space. Eventually, a patch of the less symmetric phase will appear—arising, if for no other reason, as a quantum fluctuation—and, driven by the favorable energetics, start to grow. The energy released by the transition finds form in the creation of particles. This event might be identified with the big bang.… Our answer to Leibniz's great question ‘Why is there something rather than nothing?' then becomes ‘Nothing is unstable.' ”

But the symmetry isn't really broken, Wilczek said. It's just hidden. You can always find it again if you look hard enough—in the fundamental equations, say, or perhaps inside a fireball.

The quark-gluon plasma glimpsed at RHIC was evidence that the vacuum really did start out more symmetric. Still, the vacuum was
more resilient than anyone had expected, the coherent, liquid movement of the quarks displaying some kind of residual asymmetry, rather than the symmetric free-for-all of particles in a gas. To get to the nothing, physicists were going to have to melt the vacuum even more.

As I interviewed various physicists I found that no one seemed to know what to make of the unexpected result. But when I searched around online I stumbled across an obscure clue. Apparently, something known as the “AdS/CFT correspondence” could explain the ultraliquid plasma. There wasn't enough time to figure out what that meant, nor enough space in the article to mention it, but I jotted it down in my notebook so I wouldn't forget.
Look into AdS/CFT correspondence … something to do with string theory … explains liquid fireball?

I wrote my article and sent it in just before the deadline. But I couldn't stop thinking about Wilczek's idea that nothing was unstable. It was kind of awesome, and smelled an awful lot like an explanation. My father and I had spent so much time wondering why nothing—that state of infinite, unbounded homogeneity—would ever change. If it were so perfectly homogeneous, so perfectly
symmetric
, why would it ever break? Why would it ever become a universe? Wilczek seemed to have the answer. Nothing was unstable. Universe solved.

Almost. The problem with invoking spontaneous symmetry breaking to explain that primordial alchemy, the transformation of nothing into something, of symmetry into structure, is that it requires some external force, the breeze that knocks over the universe. But there is nothing outside the universe. Wilczek had suggested that quantum fluctuations could provide the breeze, but that wasn't any better. If you use the laws of quantum mechanics to tip the universe into existence, you leave the existence of the laws themselves unexplained. Guth had acknowledged that. “I'm assuming, without necessarily any right to … that the laws of physics are somehow in place even before the universe,” he had admitted. “If we don't assume that, we can't get anywhere.”

That was pretty discouraging. A real answer to existence would have to start with nothing, and then, somehow, explain why the laws of physics pop right out. We can't just assume the existence of quantum
mechanics and then use it to explain other things, like universes. We need to explain quantum mechanics.
Why the quantum?

The story in which the universe starts out in a perfectly symmetric state that promptly breaks, creating our elaborate, frozen world, can't be the real story, because there's no one to tell it. It's a story that requires an omniscient narrator, a narrator with a God's-eye view, the kind that Smolin's slogan had strictly forbidden. Wheeler and DeWitt's damned equation didn't work because you ended up with a universe trapped in an eternal instant, a universe where nothing can ever happen—no big bang, no quark-gluon plasma, no computer simulation. It occurred to me now that perhaps my father's H-state was stuck in the same trap. The nothing could never change, because what would it be changing in reference to? You'd need some reference frame outside the nothing, which you can't have, at least not according to my father's definition of nothing as infinite and unbounded. Nothing was a one-sided coin.

What we desperately needed, I realized, was a story told from here inside the universe. Here inside the nothing, if Guth was right.
Something
is
nothing.
And if the universe
is
nothing, maybe the nothing never changes at all. Maybe the universe was never really born. Maybe nothing just
looks
like something when you're inside it.

If nothing was by definition unbounded, I thought, then all you'd need to make it look like something was a boundary. Markopoulou had said that when you're stuck inside the universe, you can't see the whole thing, only the region within your light cone. Could a light cone provide the boundary you need to turn nothing into something? I wasn't sure. After all, light cones grow with time. At best they can provide a temporary boundary. I wasn't sure if it would be enough. Besides, a light cone wasn't a
thing;
it was simply the delineation of a reference frame. How could it ever do any physical work, let alone the heavy lifting you'd need to drag a universe—even the
appearance
of a universe—out of nothing?

After a whirlwind tour of symmetry breaking and quantum chromodynamics, I finally had a chance to relax. Instead I masochistically surfed
the Internet for more on Nick Bostrom and the simulation nightmare. In the midst of my existential flagellation, I came across a website called Edge.org.

How had I not seen this before?

The site was an intellectual salon, a kind of virtual Algonquin Round Table where the most brilliant scientists, writers, and thinkers discussed and debated everything from consciousness and the origin of life to game theory and parallel universes. The site showcased the very latest in scientific thinking as it was unfolding in real time in a way that any nonscientist could understand but without dumbing it down or packaging it into sound bites.

Poking around, I discovered that the man behind Edge was one John Brockman, literary agent and self-made cultural impresario. Brockman had started off in the avant-garde art and film scene in 1960s Manhattan, where, at twenty-five, he was hanging out with the likes of Andy Warhol, John Cage, Robert Rauschenberg, and Bob Dylan, organizing events for multimedia artists and running the independent leg of the New York Film Festival.

After Cage lent him a copy of
Cybernetics
and Rauschenberg recommended books by James Jeans and George Gamow, Brockman became interested in science and developed a hunch that scientists would emerge as the leading public intellectuals who, like the avant-garde artists, would shape public discourse by forcing people to question their most basic assumptions about the world. This couldn't happen, though, until the scientists had a direct route by which to engage the public. So in 1973 Brockman founded Brockman, Inc., a literary agency that specialized in encouraging scientists to write books for a lay audience.

Five years later, with physicist Heinz Pagels, Brockman created the Reality Club, an intellectual salon that met in restaurants, museums, and living rooms across Manhattan. The club met for fifteen years before Brockman moved the group online to
Edge.org
. Meanwhile, he completely transformed the world of science books; his agency's clients included huge names, such as Richard Dawkins, Steven Pinker, Sir Martin Rees, Daniel Dennett, Jared Diamond, Craig Venter, and Brian Greene. Though the workings of the Reality Club had
gone virtual, Brockman still hosted a few live salons. Once a year he'd bring a handful of scientists and writers out to his sprawling farm in western Connecticut.

The Reality Club? There was an actual Reality Club? How did one become a member of such a club? I wondered. I wasn't a scientist or a public intellectual. I wasn't anything at all, really, unless you counted budding fraudulent science journalist. But I didn't care. All I knew was that I wanted in. I wanted to engage in intellectual debate on
Edge.org
. I wanted to hang out at Brockman's farmhouse. And most of all, I wanted John Brockman to be our agent for the book that my dad and I would someday write about the nature of ultimate reality. Unfortunately, Brockman's world didn't seem like the kind of place you could weasel your way into by pretending to be something or someone else.

I clicked on Brockman's picture. There he was, gruff and imposing, sporting a linen suit and a Panama hat, looking like a cross between a mob boss and a member of the Buena Vista Social Club.

So Nick Bostrom was part of Brockman's crew. It made sense, given his penchant for taking reality and twisting it like a balloon animal. I clicked on his bio, curious to see what path had landed him at Brockman's virtual door. Apparently he had earned his Ph.D. in the philosophy of science at the London School of Economics, where he studied philosophy, logic, artificial intelligence, and computational neuroscience. But before all that, Edge explained, Bostrom had been a stand-up comedian.

You made my head explode, I thought, staring at his stern head-shot. Very funny.

A few weeks later, I was back in the suburbs of Philly to spend a few days with my parents.

“Now that you're writing more articles, do you think you can make a real career out of this?” my mother asked at the dinner table.

I put down my fork. “A journalism career? I don't know. Maybe. That's not really the point.”

“What is the point?” she asked.

“The point is to figure out the nature of ultimate reality. How to get
something from nothing. The journalism thing is just a front. It's a means to an end.”

I looked over at my father for some backup. He offered an agreeable nod.

“Well, I don't know about ultimate reality,” my mother said, “but in this reality you're an unemployed coat-check girl.”

“That's not really my fault,” I said. “It's August. People stopped wearing coats.”