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The God Particle: If the Universe Is the Answer, What Is the Question?

Page 51

by Leon Lederman


  BEFORE TIME BEGAN

  Let's go back to the prenatal universe again. We live in a universe about which we know a great deal. Like the paleontologist who reconstructs a mastodon from a fragment of a shinbone, or an archeologist who can visualize a long-defunct city from a few ancient stones, we are aided by the laws of physics emerging from the laboratories of the world. We are convinced (though we cannot prove this) that only one sequence of events, played backward, can lead via the laws of nature from our observed universe to the beginning and "before." The laws of nature must have existed before even time began in order for the beginning to happen. We say this, we believe it, but can we prove it? No. And what about "before time began"? Now we have left physics and are in philosophy.

  The concept of time is tied to the appearance of events. A happening marks a point in time. Two happenings define an interval. A regular sequence of happenings can define a "clock"—a heartbeat, the swing of a pendulum, sunrise/sunset. Now imagine a situation where nothing ever happens. No tick-tock, no meals, no happening. The very concept of time in this sterile world has no meaning. Such may have been the state of the universe "before." The Great Event, the Big Bang, was a formidable happening that created, among other things, time.

  What I am saying is that if we cannot define a clock, we cannot give a meaning to time. Consider the quantum idea of the decay of a particle, say our old friend the pion. Until it decays, there is no way of determining time in the universe of the pion. Nothing about it changes. Its structure, if we understand anything, is identical and unchanging until it decays in its own personal version of the Big Bang. Contrast this with our human experience of the decay of a homo sapiens. Believe me, there are plenty of signs that the decay is progressing or even imminent! In the quantum world, however, there is no meaning to the questions "When will the pion decay?" or "When did the Big Bang take place?" We can, on the other hand, ask the question "How long ago did the Big Bang take place?"

  We can try to imagine the pre-Big Bang universe: timeless, featureless, but in some unimaginable way beholden to the laws of physics. These give the universe, like a doomed pion, a finite probability of exploding, changing, undergoing a transition, a change of state. Here we can improve on the metaphor used to start the book. Again we compare the universe in the Very Beginning to a huge boulder on top of a towering cliff, but now it is sitting in a trough. This would make it stable according to classical physics. Quantum physics, however, permits tunneling—one of the weird effects we examined in Chapter 5—and the first event is that the boulder appears outside of the trough and, oops, goes over the edge of the cliff, falling to release its potential energy and create the universe as we know it. In very speculative models, our dear dear Higgs field plays the role of the metaphoric cliff.

  It is comforting to visualize the disappearance of space and time as we run the universe backward toward the beginning. What happens as space and time tend toward zero is that the equations we use to explain the universe break down and become meaningless. At this point we are just plumb out of science. Perhaps it is just as well that space and time cease to have meaning; it gives us the possibility that the vanishing of the concept takes place smoothly. What remains? What remains must be the laws of physics.

  When dealing with all the elegant new theories about space, time, and the beginning, an obvious frustration sets in. As opposed to almost all other periods in science—certainly since the 1500s—there seems to be no way for experiments and observations to help out, at least not in the next few days. Even in Aristotle's time, one could (at risk) count the teeth in a horse's mouth in order to enter the debate on the number of teeth the horse has. Now our colleagues are debating a subject that has only one piece of data: the existence of a universe. This of course brings us to the whimsical subtitle of our book: the universe is the answer but damned if we know the question.

  RETURN OF THE GREEK

  It was almost 5 A.M. I had dozed over the last pages of Chapter 9. My deadline was (long) past, and I had no inspiration. Suddenly I heard a commotion outside our old farmhouse in Batavia. The horses in the stable were milling around and kicking. I walked out to see this guy in a toga and a pair of brand-new sandals coming out of the barn.

  LEDERMAN: Democritus! What are you doing here? DEMOCRITUS: Call those horses? You should see the Egyptian chariot horses I raised in Abdera. Seventeen hands and up. They could fly!

  LEDERMAN: Yes, well, how are you?

  DEMOCRITUS: Do you have an hour? I've been invited to the control room of the Wake Field Accelerator that just turned on in Teheran on January 12, 2020.

  LEDERMAN: Yeow! Can I come?

  DEMOCRITUS: Sure, if you behave. Here, hold my hand and say Πλανχκ Mασσ. [Planck mass]

  LEDERMAN: Πλανχκ Mασσ

  DEMOCRITUS: Louder! LEDERMAN: Πλανχκ Mασσ!

  Suddenly we were in a surprisingly small room that looked totally different from what I had expected— the command deck of Star Ship Enterprise. There were a few multicolored screens with very sharp images (high-definition TV). But the banks of oscilloscopes and dials were gone. Over in one corner a group of young men and women were engaged in an animated discussion. A technician standing next to me was punching buttons on a palm-sized box and watching one of the screens. Another technician was speaking Persian into a microphone.

  LEDERMAN: Why Teheran?

  DEMOCRITUS: Oh, some years after world peace, the UN decided to locate the New World Accelerator at the ancient crossroads of the world. The government here is one of the most stable, and they also made the best case for good geology, proximity to cheap power, water, and skilled labor and the best shishkebab south of Abdera.

  LEDERMAN: What's going on?

  DEMOCRITUS: The machine is colliding 500 TeV protons against 500 TeV antiprotons. Ever since 2005, when the Super Collider discovered the Higgs at a mass of 422 GeV, there was this urgent need to explore the "Higgs sector" to see if there are more kinds of Higgs.

  LEDERMAN: They found the Higgs?

  DEMOCRITUS: One of them. They think there is a whole family of Higgses.

  LEDERMAN: Anything else?

  DEMOCRITUS: Oh, hell, yes. You should have been here when the on-line data showed this crazy event with six jets and eight electron pairs. By now they have seen several squarks, gluinos, as well as the photino...

  LEDERMAN: Supersymmetry?

  DEMOCRITUS: Yes, as soon as the machine energies went above 20 TeV, these little guys poured out.

  Democritus called to someone in heavily accented Persian, and we were soon handed mugs of steaming fresh yak milk. When I asked for a display screen to see events, someone clamped a virtual-reality helmet over my head, and events, constructed from the data by God-knows-what-kind of computer, flashed before my eyes. I noticed that these 2020 physicists (the preschool kids of my era) still needed to be pictorially spoon-fed the information. A tall, young black woman with a spectacular Afro hairdo, carrying what looked like a computer notepad, sauntered over. Ignoring Democritus, she looked me over with some amusement. "Blue jeans, just like my grandfather used to wear. With that outfit you must be from UN headquarters. Are you inspecting us?"

  "No," I said. "I'm from Fermilab, and I've been out of the business for a few years. What's going on?"

  The next hour passed in a dazing blur of explanations of neural networks, jet algorithms, top quark and Higgs calibration points, vacuum-deposited diamond semiconductors, femtobytes, and—worse—twenty-five years of experimental progress. She was from Michigan, a product of the prestigious Detroit High School of Science. Her husband, a Kazakhstani postdoc, was employed by the University of Quito. She explained that the machine had a radius of only one hundred miles, this modest size made possible by a 1997 breakthrough in room-temperature superconductors. Her name was Mercedes.

  MERCEDES: Yeah, the Super Collider R&D group stumbled on these new materials while they were tracking down some weird effects in the niobium alloys. One thing led t
o another, and suddenly we had this cruciferous material that begins superconducting at 50 degrees Fahrenheit, about the temperature of a cool day in autumn.

  LEDERMAN: What is the critical field?

  MERCEDES: Fifty tesla! If I remember my history, your Fermilab machine was at four tesla. Today there are twenty-five companies making or growing the stuff. The economic impact in FY 2019 is about three hundred billion dollars. The super-train, which floats between New York and Los Angeles, cruises at two thousand miles per hour. Huge clumps of steel wool, energized by the new stuff, now provide pure water to most of the cities of the world. Every week we read about some new application.

  Democritus, sitting quietly up until now, bored in on the central question.

  DEMOCRITUS: Have you seen anything inside quarks?

  MERCEDES: [shaking her head, smiling] That was my Ph.D. thesis. The best measurement came out of the last Super Collider experiment. The radius of the quark is less than an incredibly small 1021 centimeters. As far as we can tell, quarks and leptons are as good an approximation to points as you can get.

  DEMOCRITUS: [jumping up and down, clapping, laughing hysterically] Atomos! Finally!

  LEDERMAN: Any surprises?

  MERCEDES: Well, with Susy and the Higgs, a young theorist from CUNY—a guy named Pedro Monteagudo—has written a new Susy-GUT equation that successfully predicts the Higgs-generated masses of all the quarks and leptons. Just as Bohr explained the energy levels in the hydrogen atom.

  LEDERMAN: Yeow! Really?

  MERCEDES: Yeah, the Monteagudo equation has taken over from Dirac, Schrodinger, and all points west. Look at my T-shirt.

  As if I needed such an invitation. But as I focused on the curious hieroglyphic displayed there, I felt a fuzzy, earthquake-like dizziness, and it all faded.

  ***

  "Shit." I was back home, groggily lifting my head off my papers. I noticed one photocopy of a news headline: CONGRESSIONAL FUNDING FOR THE SUPER COLLIDER IN DOUBT. My computer modem was beeping, and an E-mail message was "inviting" me to Washington for a Senate hearing on the SSC.

  GOOD-BYE

  You and I, dear colleague, have come a long way from Miletus. We have traversed the road of science from then and there to here and now. Regretfully we have sped past many of the milestones, major and minor. But we have paused at a few of the important sights: at Newton and Faraday, Dalton and Rutherford, and, of course, at McDonald's for a hamburger. We see a new synergy between inner and outer space, and like a driver on a forested winding road, we see occasional glimpses, obscured by trees and fog, of a towering edifice: an intellectual construct 2,500 years in the making.

  Along the way I have tried to insert some irreverent details about the scientists. It is important to distinguish between the scientists and the science. Scientists, more often than not, are people, and as such they span the enormous range of variability that makes people so ... so interesting. Scientists are serene and ambitious; they are driven by curiosity and ego; they exhibit angelic virtue and immense greed; they are wise beyond measure and childish well into their dotage; intense, obsessed, laid-back. Among the subset of humans called scientists, there are atheists, agnostics, the militandy apathetic, the deeply religious, and those who view the Creator as a personal deity, either all-wise or somewhat bumbling, like Frank Morgan in The Wizard of Oz.

  The range of abilities among scientists is also huge. This is okay because science needs the mixers of cement as well as the master architects. We count among us minds of awesome power those who are only monstrously clever, those possessed of magic hands, uncanny intuition, and that most vital of all scientific attributes: luck. We also have jerks, assholes, and those who are just dumb ... dumb!

  "You mean relative to you others," my mother once protested.

  "No, Mom, dumb like anyone is dumb."

  "So how did he get a Ph.D.?" she challenged.

  "Sitzfleisch, Mom." Sitzfleisch: the ability to sit through any task, to do it again and again until the job is somehow done. Those who give out Ph.D.'s are human too—sooner or later they give in.

  Now, if there is any unifier to this collection of human beings we call scientists, it is the pride and reverence with which each of us adds our contribution to that intellectual edifice: our science. It may be a brick, fitted meticulously and cemented into place, or it may be a magnificent lintel (to stress out the metaphor) gracing columns placed there by our masters. We build with a sense of awe, heavily tinged with skepticism, guided by what we found when we arrived, bringing all our human variables, coming to this effort from all directions, each carrying our own cultural dress and language, but somehow finding instant communication, instant understanding, and empathy in the common task of building the tower of science.

  It is time to let you go back to your real life. For the past three years I have been yearning for a time when this would be over. Now I admit that I will miss you, colleague reader. You have been my constant companion on airplanes, in very quiet, late-night writing sessions. I have pictured you as retired history teacher turf accountant, college student, wine merchant, motorcycle mechanic, high school sophomore, and, when I need cheering up, an incredibly beautiful contessa who wants to run her hands through my hair. Like a reader finishing a novel, reluctant to leave the characters behind, I will miss you.

  THE END OF PHYSICS?

  Before I go, I have a statement to make on this ultimate T-shirt business. I may have given the impression that the God Particle, once understood, will provide the ultimate revelation: how the universe works. This is the domain of the really-deep-thinkers, the particle theorists who are paid to really think deep. Some of them believe that The Road to reductionism will come to an end; we will essentially know it all. Science will then concentrate on complexity: super buckyballs, viruses, the morning traffic jam, a cure for hatred and violence ... all good stuff.

  There is another view—that we are like children (in the metaphor of Bentley Glass) playing on the shore of a vast ocean. This view allows for the truly endless frontier. Behind the God Particle is revealed a world of splendid, blinding beauty, but one to which our mind's eye will adapt. Soon we will perceive that we do not have all the answers; what is inside the electron, quark, and black hole will draw us ever on.

  I think I favor the optimists (or are they pessimists giving up job security?), those theorists who believe we will "know it all," but the experimentalist in me prevents summoning up the requisite arrogance. The experimental road to Oz, the Planck mass, to that epoch less than 10−40 seconds after The Event makes our total voyage from Miletus to Waxahachie look like a pleasure cruise on Lake Winnebago. I think not only of accelerators girdling the solar system and detector edifices to match, not only of the billions and billions of hours of sleep my students and theirs will lose, but 1 worry about the necessary sense of optimism that our society must summon if this quest is to continue.

  What we really do know and will know much better in a decade or so can be measured by the SSC energy: 40 trillion volts. But important things must also happen at energies so high as to make our forthcoming SSC collisions seem docile. There are still boundless possibilities for complete surprises. Operating under new laws of nature as unimaginable today as quantum theory (or the cesium atomic clock) would have been to Galileo, we could find ancient civilizations existing inside quarks. Gasp! Before the men in white coats arrive, let me switch to another frequently raised question.

  It is astonishing how often otherwise competent scientists forget the lessons of history, namely, that the major impacts of science on society have always come from the kind of research that drives the quest for the a-tom. Without taking anything away from genetic engineering, materials science, or controlled fusion, the quest for the a-tom has paid for itself many millionfold, and there is no sign so far that this has changed. The investment in abstract research, at less than one percent of the budgets of industrial societies, has performed much better than the Dow Jones average has for over t
hree hundred years. Yet from time to time we are terrorized by frustrated policy makers who want to focus science on the immediate needs of society, forgetting or perhaps never understanding that most of the major advances in technology that have influenced the quality and quantity of human life have come out of pure, abstract, curiosity-driven research. Amen.

  OBLIGATORY GOD ENDING

  Looking for inspiration on how to wind up this book, I studied the endings of a few dozen science books written for a general audience. They are always philosophical, and the Creator almost always appears in the favorite image of the author or in the image of the author's favorite author. I have noticed two kinds of closing summaries in popular science books. One kind is characterized by humility. The downgrading of humankind usually begins by reminding the reader that we are many times removed from centrality: our planet is not the center of the solar system, and the solar system is not the center of our galaxy, nor is our galaxy anything special as galaxies go. If this isn't enough to discourage even a Harvard man, we learn that the very material we and the things around us are made of consists of only a small sample of the fundamental objects in the universe. Then these authors note that humankind and all of its institutions and monuments matter very little to the continued evolution of the cosmos. The master of the humbling assessment may be Bertrand Russell:

 

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