Our Mathematical Universe

470 Pages·2015·6.4 MB·English

by  Max Tegmark

THIS IS A BORZOI BOOK
PUBLISHED BY ALFRED A. KNOPF
Copyright © 2014 by Max Tegmark
All rights reserved. Published in the United States by Alfred A. Knopf, a division of Random House LLC, New York, and in
Canada by Random House of Canada Limited, Toronto, Penguin Random House Companies.
www.aaknopf.com
Knopf, Borzoi Books, and the colophon are registered trademarks of Random House LLC.
Library of Congress Cataloging-in-Publication Data
Tegmark, Max, author.
Our mathematical universe : my quest for the ultimate nature of reality / Max Tegmark.—First edition.
pages cm
ISBN 978-0-307-59980-3 (hardback)
1. Cosmology—Mathematics. 2. Physics—Mathematics.
3. Plurality of worlds. I. Title.
QB981.T44 2013 523.10151—dc23 2013016020
eBook ISBN: 978-0-385-35049-5
Jacket image: sphere representing the edge of our observable Universe, seen 400,000 years after our Big Bang. Courtesy of
the author and the Planck satellite team
Jacket design by Jason Booher
v3.1
TO MEIA,
WHO INSPIRED ME TO WRITE THIS BOOK

Contents

Cover
Title Page
Copyright
Dedication
Preface
1 What Is Reality?
Not What It Seems • What’s the Ultimate Question? • The Journey Begins

Part One: Zooming Out

2 Our Place in Space
Cosmic Questions • How Big Is Space? • The Size of Earth • Distance to the Moon •
Distance to the Sun and the Planets • Distance to the Stars • Distance to the Galaxies •
What Is Space?
3 Our Place in Time
Where Did Our Solar System Come From? • Where Did the Galaxies Come From?
• Where Did the Mysterious Microwaves Come From? • Where Did the Atoms
Come From?
4 Our Universe by Numbers
Wanted: Precision Cosmology • Precision Microwave-Background Fluctuations •
Precision Galaxy Clustering • The Ultimate Map of Our Universe • Where Did Our
Big Bang Come From?
5 Our Cosmic Origins
What’s Wrong with Our Big Bang? • How Inflation Works • The Gift That Keeps on
Giving • Eternal Inflation
6 Welcome to the Multiverse
The Level I Multiverse • The Level II Multiverse • Multiverse Halftime Roundup

Part Two: Zooming In

7 Cosmic Legos
Atomic Legos • Nuclear Legos • Particle-Physics Legos • Mathematical Legos •
Photon Legos • Above the Law? • Quanta and Rainbows • Making Waves • Quantum
Weirdness • The Collapse of Consensus • The Weirdness Can’t Be Confined •
Quantum Confusion
8 The Level III Multiverse
The Level III Multiverse • The Illusion of Randomness • Quantum Censorship • The
Joys of Getting Scooped • Why Your Brain Isn’t a Quantum Computer • Subject,
Object and Environment • Quantum Suicide • Quantum Immortality? • Multiverses
Unified • Shifting Views: Many Worlds or Many Words?

Part Three: Stepping Back

9 Internal Reality, External Reality and Consensus Reality
External Reality and Internal Reality • The Truth, the Whole Truth and Nothing but
the Truth • Consensus Reality • Physics: Linking External to Consensus Reality
10 Physical Reality and Mathematical Reality
Math, Math Everywhere! • The Mathematical Universe Hypothesis • What Is a
Mathematical Structure?
11 Is Time an Illusion?
How Can Physical Reality Be Mathematical? • What Are You? • Where Are You?
(And What Do You Perceive?) • When Are You?
12 The Level IV Multiverse
Why I Believe in the Level IV Multiverse • Exploring the Level IV Multiverse:
What’s Out There? • Implications of the Level IV Multiverse • Are We Living in a
Simulation? • Relation Between the MUH, the Level IV Multiverse and Other
Hypotheses • Testing the Level IV Multiverse
13 Life, Our Universe and Everything
How Big Is Our Physical Reality? • The Future of Physics • The Future of Our
Universe—How Will It End? • The Future of Life • The Future of You—Are You
Insignificant?
Acknowledgments
Suggestions for Further Reading
Index
A Note About the Author

Preface

I’m truly grateful to everyone who has encouraged and helped me write this book, including:
my family, friends, teachers, colleagues and collaborators for support and inspiration over
the years,
Mom for sharing her passion and curiosity for life’s big questions,
Dad for sharing his fascination and wisdom about mathematics and its meaning,
my sons, Philip and Alexander, for asking such great questions about the world and for
unwittingly providing anecdotes for the book,
all the science enthusiasts around the world who’ve contacted me over the years with
questions, comments and encouragement to pursue and publish my ideas,
my agents, John and Max Brockman, for convincing me to write this book and setting
everything in motion,
those who gave me feedback on parts of the manuscript, including Mom, my brother Per,
Josh Dillon, Marty Asher, David Deutsch, Louis Helm, Andrei Linde, Jonathan Lindström,
Roy Link, David Raub, Shevaun Mizrahi, Mary New, Sandra Simpson, Carl Shulman and Jaan
Tallinn.
the superheroes who commented on drafts of the entire book, namely Meia, Dad, Paul
Almond, Julian Barbour, Phillip Helbig, Adrian Liu, Howard Messing, Dan Roberts, Edward
Witten and my editor, Dan Frank, and most of all,
my beloved wife, Meia, my muse and fellow traveler, who’s given me more
encouragement, support and inspiration than I ever dreamed of.