Copyright © 2011 by Richard Panek
All rights reserved
For information about permission to reproduce selections from this book, write to Permissions, Houghton Mifflin Harcourt Publishing Company, 215 Park Avenue South, New York, New York 10003.
Library of Congress Cataloging-in-Publication Data
Panek, Richard.
The four-percent universe : dark matter, dark energy, and the race to discover the rest of reality / Richard Panek.
p. cm.
Includes bibliographical references and index.
ISBN 978-0-618-98244-8
1. Cosmology. 2. Physics. 3. Astrophysics. I. Title.
QB981.P257 2010
523.1—dc22 2010025838
Book design by Lisa Diercks
This book is typeset in Bulmer, Hydra Text, and Belizio.
Printed in the United States of America
DOC 10 9 8 7 6 5 4 3 2 1
Some passages in this book appeared, usually in different form, in Discover, the New York Times Magazine, Sky & Telescope, and Smithsonian.
Portions of chapter 11 are based on work supported by the National Science Foundation under Grant No. 0739893. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author and do not necessarily reflect the views of the National Science Foundation.