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Bored during Mass at the cathedral in Pisa, the seventeen-year-old Galileo regarded the chandelier swinging overhead--and remarked, to his great surprise, that the lamp took as many beats to complete an arc when hardly moving as when it was swinging widely. Galileo's Pendulum tells the story of what this observation meant, and of its profound consequences for science and technology.
The principle of the pendulum's swing--a property called isochronism--marks a simple yet fundamental system in nature, one that ties the rhythm of time to the very existence of matter in the universe. Roger Newton sets the stage for Galileo's discovery with a look at biorhythms in living organisms and at early calendars and clocks--contrivances of nature and culture that, however adequate in their time, did not meet the precise requirements of seventeenth-century science and navigation. Galileo's Pendulum recounts the history of the newly evolving time pieces--from marine chronometers to atomic clocks--based on the pendulum as well as other mechanisms employing the same physical principles, and explains the Newtonian science underlying their function. The book ranges nimbly from the sciences of sound and light to the astonishing intersection of the pendulum's oscillations and quantum theory, resulting in new insight into the make-up of the material universe. Covering topics from the invention of time zones to Isaac Newton's equations of motion, from Pythagoras' theory of musical harmony to Michael Faraday's field theory and the development of quantum electrodynamics, Galileo's Pendulum is an authoritative and engaging tour through time of the most basic all-pervading system in the world.
(20040530)
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GALILEO’S PENDULUM GALILEO’S PENDULUM From the Rhythm of Time to the Making of Matter roger g. newton harvard university press Cambridge, Massachusetts London, England 2004 Copyright © 2004 by the President and Fellows of Harvard College All rights reserved Printed in the United States of America Library of Congress Cataloging-in-Publication Data Newton, Roger G. Galileo’s pendulum : from the rhythm of time to the making of matter / Roger G. Newton. p. cm. Includes bibliographical references and index. ISBN 0-674-01331-X (alk. paper) 1. Time measurements. 2. Pendulum. I. Title. QB209.N48 2004 529′.7—dc22 2003056972 To Benjamin, whose time has just begun Contents Preface Introduction 1 Biological Timekeeping: The Body’s Rhythms ix 1 4 2 The Calendar: Different Drummers 24 3 Early Clocks: Home-Made Beats 34 4 The Pendulum Clock: The Beat of Nature 48 5 Successors: Ubiquitous Timekeeping 65 6 Isaac Newton: The Physics of the Pendulum 83 7 Sound and Light: Oscillations Everywhere 98 8 The Quantum: Oscillators Make Particles 123 Notes 139 References 142 Illustration Credits 146 Index 149 Preface T his book is about both ancient history and modern science. Though its subject is not Greek mythology, its aim may be freely interpreted as describing the pervasive influence of Terpsichore, the Muse of dance and rhythm, over our lives, and how science, through Galileo’s pendulum, managed to tame that which Euripides called “measureless and wild”—time. The periodic motion of that swinging bob exerted a remarkable influence on the development of modern science and mathematics. This influence eventually extended over not only our understanding of all the natural phenomena that vary with time but even the way science views the very existence of the material world—the particles that make up the objects we touch as well as the light and sound with which w