Relativity The Special And The General Theory

penguin classics R E L AT I V I T Y albert einstein, one of the greatest thinkers of the twentieth century, was born in 1879 in Ulm, Germany, to German-Jewish parents. As a young adult, he moved to Switzerland, where he became a citizen and where he published his first great theories in the early 1900s, while working as a patent clerk. It was as a professor at the University of Berlin that he finished the general theory of relativity in 1915–17. Later, Einstein left Germany and came to the United States to join the Institute for Advanced Study at Princeton. In his later years he became more interested in social issues and penned several books, including About Zionism, on the state of Israel. He died in 1955 at the age of seventy-six. Educated as a physicist at Cambridge University, nigel calder began his full-time writing career on the original staff of New Scientist magazine, and later became its editor. In 1966 he left that job to devote himself independently to his own writing. Calder’s subjects have ranged from particle physics to social psychology. One of his many books is the best-selling Einstein’s Universe, which Penguin reissued in an updated form in 2005 in celebration of the 100th anniversary of Einstein’s first groundbreaking theories. He lives in Sussex, England, with his wife, Liz, an artist and former teacher of Italian. albert einstein Relativity the special and the general theory Translated by robert w. lawson, University of Sheffield Introduced by nigel calder penguin books relativity penguin books Published by the Penguin Group Penguin Group (USA) Inc., 375 Hudson Street, New York, New York 10014, U.S.A. Penguin Group (Canada), 90 Eglinton Avenue East, Suite 700, Toronto, Ontario, Canada M4P 2Y3 (a division of Pearson Penguin Canada Inc.) Penguin Books Ltd, 80 Strand, London WC2R 0RL, England Penguin Ireland, 25 St Stephen’s Green, Dublin 2, Ireland (a division of Penguin Books Ltd) Penguin Group (Australia), 250 Camberwell Road, Camberwell, Victoria 3124, Australia (a division of Pearson Australia Group Pty Ltd) Penguin Books India Pvt Ltd, 11 Community Centre, Panchsheel Park, New Delhi - 110 017, India Penguin Group (NZ), cnr Airborne and Rosedale Roads, Albany, Auckland 1310, New Zealand (a division of Pearson New Zealand Ltd) Penguin Books (South Africa) (Pty) Ltd, 24 Sturdee Avenue, Rosebank, Johannesburg 2196, South Africa Penguin Books Ltd, Registered Offices: 80 Strand, London WC2R 0RL, England Relativity translated by Robert W. Lawson first published in Great Britain by Methuen & Co. Ltd. 1920 First published in the United States of America by Henry Holt and Company 1920 This edition with an introduction by Nigel Calder published in Penguin Books 2006 Introduction copyright © Nigel Calder, 2006 All rights reserved library of congress cataloging-in-publication data Einstein, Albert, 1879–1955. [Über die spezielle und die allgemeine Relativitätstheorie. English] Relativity: the special and the general theory / Albert Einstein; introduced by Nigel Calder. p. cm.—(Penguin classics) Previously published (in English): New York : H. Holt, 1920. Includes bibliographical references and index. ISBN: 1-4362-9508-4 1. Relativity (Physics) I. Calder, Nigel. II. Title. III. Series. QC173.55.E384513 2006 530.11—dc22 2005058696 Set in Designed by The scanning, uploading, and distribution of this book via the Internet or via any other means without the permission of the publisher is illegal and punishable by law. Please purchase only authorized electronic editions, and do not participate in or encourage electronic piracy of copyrighted materials. Your support of the author’s rights is appreciated. Contents Introduction by Nigel Calder Suggestions for Further Reading Preface by Albert Einstein vii xxix 3 pa r t i The Special Theory of Relativity 1. Physical Meaning of G