Fundamentals Read online

  ALSO BY FRANK WILCZEK

  A Beautiful Question

  The Lightness of Being

  Fantastic Realities

  Longing for the Harmonies

  PENGUIN PRESS

  An imprint of Penguin Random House LLC

  penguinrandomhouse.com

  Copyright © 2021 by Frank Wilczek

  Penguin supports copyright. Copyright fuels creativity, encourages diverse voices, promotes free speech, and creates a vibrant culture. Thank you for buying an authorized edition of this book and for complying with copyright laws by not reproducing, scanning, or distributing any part of it in any form without permission. You are supporting writers and allowing Penguin to continue to publish books for every reader.

  library of congress cataloging-in-publication data

  Names: Wilczek, Frank, author.

  Title: Fundamentals : ten keys to reality / Frank Wilczek.

  Description: New York : Penguin Press, 2021. | Includes index.

  Identifiers: LCCN 2020020086 (print) | LCCN 2020020087 (ebook) | ISBN 9780735223790 (hardcover) | ISBN 9780735223899 (ebook)

  Subjects: LCSH: Reality.

  Classification: LCC QC6.4.R42 W55 2021 (print) | LCC QC6.4.R42 (ebook) | DDC 530.01—dc23

  LC record available at https://lccn.loc.gov/2020020086

  LC ebook record available at https://lccn.loc.gov/2020020087

  Cover design: Stephanie Ross

  Cover image: Konstantin Raskudakin / Shutterstock

  pid_prh_5.6.1_c0_r1

  For Betsy:

  revelations

  Orchestrated multitudes spin out

  The textured patterns which make our lives.

  Birth, learning, love, and unsought age—

  Gifts we did not earn, limits we did not grant.

  Space grows in silence, past our grasp.

  Celestial bodies, thinly sprinkled there

  Broadcast in obedience to ideal laws.

  They do not speak the language sung at cradles.

  Time is change, impartially enforced.

  In ancient things we see its awesome scope

  While tiny, perfect clocks attest its vigor.

  Time long predates us, and will long outlive us.

  As in my mind I make my world anew

  The cherished, closest thing is ever you.

  CONTENTS

  Preface: Born Again

  Introduction

  I. WHAT THERE IS

  1. There’s Plenty of Space

  2. There’s Plenty of Time

  3. There Are Very Few Ingredients

  4. There Are Very Few Laws

  5. There’s Plenty of Matter and Energy

  II. BEGINNINGS AND ENDS

  6. Cosmic History Is an Open Book

  7. Complexity Emerges

  8. There’s Plenty More to See

  9. Mysteries Remain

  10. Complementarity Is Mind-Expanding

  Afterword: The Long Voyage Home

  Acknowledgments

  Appendix

  Index

  PREFACE: BORN AGAIN

  I

  This is a book about fundamental lessons we can learn from the study of the physical world. I’ve met many people who are curious about the physical world and eager to learn what modern physics says about it. They might be lawyers, doctors, artists, students, teachers, parents, or simply curious people. They have intelligence, but not knowledge. Here I’ve tried to convey the central messages of modern physics as simply as possible, while not compromising accuracy. I’ve kept my curious friends and their questions constantly in mind while writing the book.

  To me, those fundamental lessons include much more than bare facts about how the physical world works. Those facts are both powerful and strangely beautiful, to be sure. But the style of thought that allowed us to discover them is a great achievement, too. And it’s important to consider what those fundamentals suggest about how we humans fit into the big picture.

  II

  I’ve selected ten broad principles as my fundamentals. Each forms the theme of one chapter. In the body of each chapter, I explain and document that chapter’s theme from different perspectives, and then make some informed guesses about its future development. Those informed guesses were fun to create, and I hope they’re exciting to read. They are meant to convey another fundamental message: that our understanding of the physical world is still growing and changing. It is a living thing.

  I’ve been careful to separate speculations from facts and, for the facts, to indicate the nature of the observations and experiments that establish them. For perhaps the most fundamental message of all is that we do understand many aspects of the physical world very deeply. As Albert Einstein put it, “The fact that [the universe] is comprehensible is a miracle.” That, too, was a hard-won discovery.

  Precisely because it is so surprising, the comprehensibility of the physical universe must be demonstrated, not assumed. The most convincing proof is that our understanding, though incomplete, has let us accomplish great and amazing things.

  In my research, I try to fill gaps in our understanding and to design new experiments to push the frontiers of possibility. It’s been a joy for me, in writing this book, to step back and reflect, wonderstruck, on some highlights of what generations of scientists and engineers, cooperating across time and space, have already accomplished.

  III

  Fundamentals is meant, as well, to offer an alternative to traditional religious fundamentalism. It takes up some of the same basic questions, but addresses them by consulting physical reality, rather than texts or traditions.

  Many of my scientific heroes—Galileo Galilei, Johannes Kepler, Isaac Newton, Michael Faraday, James Clerk Maxwell—were devout Christians. (In this they were representative of their times and surroundings.) They thought that they could approach and honor God by studying His work. Einstein, though he was not religious in a conventional sense, had a similar attitude. He often referred to God (or “the Old One”), as he did in one of his most famous quotations: “Subtle is the lord, but malicious he is not.”

  The spirit of their enterprise, and mine here, transcends specific dogmas, whether religious or antireligious. I like to state it this way: In studying how the world works, we are studying how God works, and thereby learning what God is. In that spirit, we can interpret the search for knowledge as a form of worship, and our discoveries as revelations.

  IV

  Writing this book changed my perception of the world. Fundamentals began as an exposition but grew into a contemplation. As I reflected on the material, two overarching themes emerged unexpectedly. Their clarity and depth have astonished me.

  The first of those themes is abundance. The world is large. Of course, a good look at the sky on a clear night is enough to show you that there’s lots of space “out there.” When, after more careful study, we put numbers to that size, our minds are properly boggled. But the largeness of space is only one aspect of Nature’s abundance, and it is not the one most central to human experience.

  For one thing, as Richard Feynman put it, “there’s plenty of room at the bottom.” Each of our human bodies contains far more atoms than there are stars in the visible universe, and our brains contain about as many neurons as there are stars in our galaxy. The universe within is a worthy complement to the universe beyond.

  As for space, so also for time. Cosmic time is abundant. The quantity of time reaching back to the big bang dwarfs a human lifetime. And yet, as we’ll discuss, a full human lifetime contains far more moments of consciousness t
han universal history contains human lifespans. We are gifted with an abundance of inner time.

  The physical world is abundant, as well, in hitherto untapped resources for creation and perception. Science reveals that the nearby world contains, in known and accessible forms, far more energy and usable material than humans presently exploit. This realization empowers us and should whet our ambitions.

  Our unaided perception brings in only a few slivers of the reality that scientific investigation reveals. Consider, for example, vision. Our sense of vision is our widest and most important portal to the external world. But it leaves so much unseen! Telescopes and microscopes reveal vast treasure troves of information, encoded in light, that ordinarily come to our eyes unrecognized. Moreover, our vision is limited to one octave—the span of visible light—from an infinite keyboard of electromagnetic radiation, which runs from radio waves to microwaves to infrared on one side, and from ultraviolet to x-rays and gamma rays on the other. And even within our one octave, our color vision is blurry. While our senses fail to perceive many aspects of reality, our minds allow us to transcend our natural limits. It is a great, continuing adventure to widen the doors of perception.

  V

  The second theme is that to appreciate the physical universe properly one must be “born again.”

  As I was fleshing out the text of this book, my grandson Luke was born. During the drafting, I got to observe the first few months of his life. I saw how he studied his own hands, wide-eyed, and began to realize that he controlled them. I saw the joy with which he learned to reach out and grasp objects in the external world. I watched him experiment with objects, dropping them and searching for them, and repeating himself (and repeating himself . . .), as if not quite certain of the result, but laughing in joy when he found them.

  In these and many other ways, I could see that Luke was constructing a model of the world. He approached it with insatiable curiosity and few preconceptions. By interacting with the world, he learned the things that nearly all human adults take for granted, such as that the world divides into self and not-self, that thoughts can control movements of self but not of not-self, and that we can look at bodies without changing their properties.

  Babies are like little scientists, making experiments and drawing conclusions. But the experiments they do are, by the standards of modern science, quite crude. Babies work without telescopes, microscopes, spectroscopes, magnetometers, particle accelerators, atomic clocks, or any other of the instruments we use to construct our truest, most accurate world-models. Their experience is limited to a small range of temperatures; they are immersed in an atmosphere with a very special chemical composition and pressure; Earth’s gravity pulls them (and everything in their environment) down, while Earth’s surface supports them . . . and so forth.

  Babies construct a world-model that accounts for what they experience within the bounds of their perception and environment. For practical purposes, that’s the right plan. To cope with the everyday world, it is efficient, and reasonable, when we are children, to take lessons from the everyday world.

  But modern science reveals a physical world very different from the model we construct as babies. If we once again open ourselves up to the world, curious and without preconceptions— if we allow ourselves to be born again—we come to understand the world differently.

  Some things, we must learn. The world is built from a few basic building blocks, which follow strict but strange and unfamiliar rules.

  Some things, we must unlearn.

  Quantum mechanics reveals that you cannot observe something without changing it, after all. Each person receives unique messages from the external world. Imagine that you and a friend sit together in a very dark room, observing a dim light. Make the light very, very dim, say, by covering it with layers of cloth. Eventually, both you and your friend will see only intermittent flashes. But you will see flashes at different times. The light has broken up into individual quanta, and quanta cannot be shared. At this fundamental level, we experience separate worlds.

  Psychophysics reveals that consciousness does not direct most actions, but instead processes reports of them, from unconscious units that do the work. Using a technique known as transcranial magnetic stimulation (TMS), it is possible to stimulate the left or right brain motor centers in a subject’s brain, at the experimenter’s discretion. A properly sculpted TMS signal to the right motor center will cause a twitch of the left wrist, while a properly sculpted TMS signal to the left motor center will cause a twitch of the right wrist. Alvaro Pascual-Leone used this technique ingeniously in a simple experiment that has profound implications. He asked subjects, upon receiving a cue, to decide whether they wanted to twitch their right or their left wrist. Then they were instructed to act out their intention upon receiving an additional cue. The subjects were in a brain scanner, so the experimenter could watch their motor areas preparing the twitch. If they had decided to twitch their right wrist, their left motor area was active; if they decided to twitch their left wrist, their right motor area was active. It was possible, in this way, to predict what choice had been made before any motion occurred.

  Now comes a revealing twist. Occasionally Pascual-Leone would apply a TMS signal to contradict (and, it turns out, override) the subject’s choice. The subject’s twitch would then be the one that TMS imposed, rather than the one he or she originally chose. The remarkable thing is how the subjects explained what had happened. They did not report that some external force had possessed them. Rather, they said, “I changed my mind.”

  Detailed study of matter reveals that our body and our brain—the physical platform of our “self”—is, against all intuition, built from the same stuff as “not-self,” and appears to be continuous with it.

  In our rush to make sense of things, as infants, we learn to misunderstand the world, and ourselves. There’s a lot to unlearn, as well as a lot to learn, on the voyage to deep understanding.

  VI

  The process of being born again can be disorienting. But, like a roller-coaster ride, it can also be exhilarating. And it brings this gift: To those who are born again, in the way of science, the world comes to seem fresh, lucid, and wonderfully abundant. They come to live out William Blake’s vision:

  To see a World in a Grain of Sand

  And a Heaven in a Wild Flower

  Hold Infinity in the palm of your hand

  And Eternity in an hour

  INTRODUCTION

  I

  The universe is a strange place.

  To newborn infants, the world presents a jumble of bewildering impressions. In sorting it out, a baby soon learns to distinguish between messages that originate from an internal world and those that originate from an external world. The internal world contains both feelings, such as hunger, pain, well-being, and drowsiness, and the netherworld of dreams. Within it, too, are private thoughts, such as those that direct her gaze, her grasp, and, soon, her speech.

  The external world is an elaborate intellectual construction. Our baby devotes much of her time to making it. She learns to recognize stable patterns in her perception that, unlike her own body, do not respond reliably to her thoughts. She organizes those patterns into objects. She learns that those objects behave in somewhat predictable ways.

  Eventually our baby, now a child, comes to recognize some of the objects as beings similar to herself, beings with whom she can communicate. After exchanging information with those beings, she becomes convinced that they, too, experience internal and external worlds and, remarkably, that all of them share many objects in common, and that those objects obey the same rules.

  II

  Understanding how to control the common external world—in other words, the physical world—is, of course, a vital practical problem, with many aspects. For example, to thrive in a hunter-gatherer society, our child would have to learn where to find water; which plants and animals are good
to eat, and how to find, raise, or hunt them; how to prepare and cook food, and many other facts and skills.

  In more complex societies, other challenges arise, such as how to make specialized tools, how to build lasting structures, and how to keep track of time. Successful solutions to the problems posed by the physical world get discovered, shared, and accumulated over generations. They become, for each society, its “technology.”

  Nonscientific societies often develop rich and complex technologies. Some of those technologies enabled—and still do enable—people to thrive in difficult environments, such as the Arctic or the Kalahari Desert. Others supported the construction of great cities and impressive monuments, such as the Egyptian and Mesoamerican pyramids.

  Still, throughout most of human history, prior to the emergence of the scientific method, the development of technologies was haphazard. Successful techniques were discovered more or less by accident. Once stumbled upon, they were transmitted in the form of very specific procedures, rituals, and traditions. They did not form a logical system, nor was there a systematic effort to improve them.

  Technologies based on “rules of thumb” allowed people to survive, reproduce, and, often, to enjoy some leisure and achieve satisfying lives. For most people, in most cultures, over most of history, that was enough. People had no way to know what they were missing, or that what they were missing might be important to them.

  But now we know that they were missing a lot. This figure, which shows the development of human productivity with time, speaks for itself, and it speaks volumes.

  III

  The modern approach to understanding the world emerged in Europe in the seventeenth century. There were partial anticipations earlier, and elsewhere. But the constellation of breakthroughs known as the Scientific Revolution provided inspiring examples of what could be achieved by human minds creatively engaged with the physical world, and the methods and attitudes that led to those breakthroughs gave clear models for future exploration. With that impetus, science as we know it began. It has never looked back.