A Short History of Physics in the American Century NEW HISTORIES OF SCIENCE, TECHNOLOGY, AND MEDICINE Series Editors Margaret C. Jacob Spencer R. Weart A Short History of Physics in the American Century David C. Cassidy Harvard University Press Cambridge, Massachusetts, and London, England 2011 Copyright © 2011 by David C. Cassidy All rights reserved Printed in the United States of America Library of Congress Cataloging-in- Publication Data Cassidy, David C., 1945– A short history of physics in the American century / David C. Cassidy. p. cm.—(New histories of science, technology, and medicine) Includes bibliographical references and index. ISBN 978-0- 674- 04936- 9 (alk. paper) 1. Physics— United States— History. 2. Physicists— United States. I. Title. QC9.U5C36 2011 530.0973'0904—dc22 2011004099 Contents Introduction 1 1 Entering the New Century 6 2 American Physics Comes of Age 25 3 Surviving the Depression 52 4 The Physicists’ War 72 5 Taming the Endless Frontier 90 6 The New Physics 106 7 Sputnik: Action and Reaction 124 8 Revising the Partnership 144 Appendix: Tables 171 Notes 177 Acknowledgments 201 Index 203 A Short History of Physics in the American Century Introduction Physicists were in a celebratory mood at the turn to the twenty- fi rst cen- tury. Nearly every year of the de cade straddling 2000 brought celebra- tions of discoveries and breakthroughs that had revolutionized physics and transformed the world in which we live. The hundredth anniversaries of the discoveries of X-rays (1895), radioactivity (1896), the electron (1897), the idea of the quantum (1900), and Albert Einstein’s “year of miracles” (1905) fell during the years from 1995 to 2005. Those years also encompassed the seventy- fi fth anniversary of the breakthrough to quantum mechanics (1925), the sixtieth anniversary of the start of the Manhattan Project (1942), the fi ftieth anniversary of the transistor (1947), the fortieth anniversary of the laser (1960), and the tenth anniversary of high- temperature superconductivity (1986). The hundredth anniversaries of the founding of the premier research journal Physical Re- view (1893) and the American physicists’ main professional orga ni za tion, the American Physical Society (1899), also fell within the last years of the century, marking milestones in the story of American physics during the past century. Many of these more recent developments and discoveries had occurred within the United States and within a discipline of research that itself had undergone a remarkable transformation. During the twentieth century, American physics followed an arching trajectory that extended from rela- tively humble beginnings in 1900 to a place on the world stage by the early 1930s, to a place of preeminence by the 1950s, and fi nally by the end of the 2 Introduction century to a more modest place as an internationalized discipline within a global community of competitors. This is a book about that trajectory: the people, the discoveries, the institutions. It includes both the well-known and the less well- known physicists and institutions, as well as often ne- glected minority participants. Here “American physics” refers to physics in the United States of America, the profession and the science. The trajectory of American physics did not proceed in isolation but closely tracked and sometimes led the international growth, expansion, and shifts occurring within physics itself before and during the century. It also closely followed the trajectory of American history. By 1900 the United States was poised for rapid growth and infl uence. The nation had recently achieved industrialization, and its economy was primed for expansion. At the same time, as new discoveries emerged in Europe, new technologies reached commercialization in the United States, helping spur the demand for home- grown discoveries. The nation’s infl uence grew as it became a key player on the world stage during the fi rst and second world wars, and as it became the main competitor with the Soviet Union during the de cades of the Cold War, which ended in the early 1990s. As the United States emerged from the world wars as one of the most powerful economic, military, and scientifi c nations on the planet, some of its leaders believed that its time had come to proclaim “the American Century,” a century that they believed would be dominated, in rather imperial terms, by the spread of American democracy, culture, industry, and infl uence across the globe, all supported by the world’s fi nest innovators in science and technology.1 Among those innovators were, of course, the physicists who had helped win the war with radar and the atomic bomb. As the Cold War concluded during the last de cade of the century, the United States found itself the last remaining superpower. But, after relinquishing its postwar commitment to scientifi c leadership early in the last third of the century, the nation also found itself struggling to maintain the competitive quality of its education and to foster its increasingly internationalized research base within a global environment populated by other industrial and industrializing nations intent upon rais- ing their scientifi c expertise to equal or greater status. How did all this happen? What forces were at work in the United States and within physics and the physics profession that brought about these changes in the status of its science? Introduction 3 What we call science is the body of knowledge about nature that has been assembled, tested, and constantly retested and revised by many generations of people in many different nations and cultures. It is, in the end, a prod- uct of our universal curiosity and drive to comprehend the natural world in which we live. But it is also a product of its time and of the people and in- stitutions and cultures that produce it. By its name, physics focuses on the physical aspects of nature, the search for an understanding of the laws of nature that govern the properties and behavior of physical matter. As the properties, behaviors, and types of matter under investigation expanded and shifted over time and for a variety of reasons, the physics discipline itself expanded dramatically over the course of the century. This led to the growth of new, specialized subdisciplines, such as condensed- matter, plasma, medical, chemical, and computational physics, and to new “hyphen- ated” fi elds such as astrophysics, geophysics, and biophysics. Because of the human quality of science and of the need for constant cooperation, testing, and revising, a nation’s success in science arises from its ability to create a community of trained scientists and to support and encourage that community by creating the conditions that will foster re- search on the forefront of knowledge. Among these conditions are a steady supply of motivated young people prepared for the rigors of training and future research; ready access to higher education; suffi cient funding, equip- ment, and professional standards; freedom to publish and debate results; and, for a newly emerging community, a widely accepted vision of its work and goals that enables it to create and maintain an in de pen dent profes- sional identity within science and the broader society. By itself, science produces only knowledge about nature. It does not di- rectly produce any new goods or commercial products. But modern scien- tifi c research is expensive, highly technical, and often frustrating in that useful results are never guaranteed. As have scientists throughout history, American physicists found it necessary to rely for research support, social recognition, and training and employment on partnerships with other, more powerful institutions within society. Among them were government, industry, military, philanthropy, education, and the general public. And these institutions responded as they recognized—and were encouraged to recognize— at least two advantages that a healthy science, and physics, can bring. The fi rst was best captured in Francis Bacon’s famous statement 4 Introduction that “knowledge is power”: the power to produce new technologies lead- ing to new consumer products, new instruments of research, new medical applications, new military weapons, and new solutions to national prob- lems such as energy resources. A second advantage of a thriving physics is that it can be regarded as one component of a nation’s culture and learn- ing and thus as a valued indicator of a nation’s cultural standing. This was especially important during the Cold War, a competition that both sides regarded as a clash, not just between two superpowers, but between two po liti cal, social, and economic systems whose strength and superiority were exemplifi ed by the strength and superiority of their science and culture. The history of American physics during the twentieth century is, of course, a very big subject and one that can be approached from many dif- ferent perspectives. In addition, a great deal has already been written about the history of American physics during the past century— from histories of industrial facilities, philanthropic foundations, and accelerator laborato- ries to detailed studies of important discoveries, developments, and people; to accounts of defi ning events such as the Manhattan Project and radar development; to so cio log i cal, anthropological, and philosophical analyses of physicists and their work; to end-of- century surveys of advances in physics during the past century; to scholarly histories of the overall growth of the American physics discipline and science. Many of these studies, some published de cades ago, are still considered authoritative within the spaces they occupy. They include, in par tic u lar, works by Daniel Kevles, A. Hunter Dupree, Richard Rhodes, and many of the other authors listed in the notes to this book. Although it was fi rst published in 1971, Kevles’s The Physicists: The History of a Scientifi c Community in Modern America remains the standard historical account of the American academic physics profession from the late nineteenth century through the fi rst two- thirds of the twentieth cen- tury.