Table Of ContentWorld Scientific Series in 20th Century Physics - Vol. 26
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Seminal Papers of Julian Schwinger
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World Scientific
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World Scientific Series in 20th Century Physics
Published
Vol. 1 Gauge Theories - Past and Future
edited by R. Akhoury, B. de Wit, and P. van Nieuwenhuizen
Vol. 2 Scientific Highlights in Memory of Leon van Hove
edited by F. Nicodemi
Vol. 3 Selected Papers, with Commentary, of T. H. R. Skyrme
edited by G. E. Brown
Vol. 4 Salamfestschrift
edited by A. Ali, J. Ellis and S. Randjbar-Daemi
Vol. 5 Selected Papers of Abdus Salam (with Commentary)
edited by A. Ali, C. Isham, T. Kibble and Riazuddin
Vol. 6 Research on Particle Imaging Detectors
edited by G. Charpak
Vol. 7 A Career in Theoretical Physics
edited by P. W. Anderson
Vol. 8 Lepton Physics at CERN and Frascati
edited by N. Cabibbo
Vol. 9 Quantum Mechanics, High Energy Physics and Accelerators - Selected Papers
of J. S. Bell (with Commentary)
edited by M. Bell, K. Gottfried and M. Veltman
Vol. 10 How We Learn; How We Remember: Toward an Understanding of Brain
and Neural Systems - Selected Papers of Leon N. Cooper
edited by L. N. Cooper
Vol. 11 30 Years of the Landau Institute - Selected Papers
edited by I. M. Khalatnikov and V. P. Mineev
Vol. 12 Sir Nevill Mott - 65 Years in Physics
edited by N. Mott and A. S. Alexandrov
Vol. 13 Broken Symmetry - Selected Papers of Y. Nambu
edited by T. Eguchi and K. Nishijima
Vol. 14 Reflections on Experimental Science
edited by M. L. Perl
Vol. 15 Encounters in Magnetic Resonances - Selected Papers of Nicolaas Bloembergen
(with Commentary)
edited by N. Bloembergen
Vol. 16 Encounters in Nonlinear Optics - Selected Papers of Nicolaas Bloembergen
(with Commentary)
edited by N. Bloembergen
Vol. 17 The Collected Works of Lars Onsager (with Commentary)
edited by P. C. Hemmer, H. Holden and S. K. Ratkje
Vol. 18 Selected Works of Hans A. Bethe (with Commentary)
edited by Hans A. Bethe
Vol. 19 Selected Scientific Papers of Sir Rudolf Peierls (with Commentary)
edited by R. H. Dalitz and R. Peierls
Vol. 20 The Origin of the Third Family
edited by O. Bamabei, L. Maiani, R. A. Ricci and F. R. Monaco
Vol. 21 Spectroscopy with Coherent Radiation - Selected Papers of Norman F. Ramsey
(with Commentary)
edited by N. F. Ramsey
Vol. 22 A Quest for Symmetry - Selected Works of Bunji Sakita
edited by K. Kikkawa, M. Virasoro and S. R. Wadia
Vol. 23 Selected Papers of Kun Huang (with Commentary)
edited by B.-F. Zhu
Vol. 24 Subnuclear Physics - The First 50 Years: Highlights from Erice to ELN
by A. Zichichi; edited by 0. Bamabei, P. Pupillo and F. R. Monaco
Vol. 25 The Creation of Quantum Chromodynamics and the Effective Energy
by V. N. Gribov, G. 't Hooft, G. Veneziano and V. F. Weisskopf,•
edited by L. N. Lipatov
Forthcoming
The Creation of Quantum Chromodynamics and the Effective Energy
edited by L. N. Lipatov
Selected Papers of Richard Feynman (with Commentary)
edited by L. M. Brown
In Conclusion - A Collection of Summary Talks in High Energy Physics
edited by J. D. Bjorken
Selected Papers of Kenneth G. Wilson
edited by M. E. Peskin and B. Baaquie
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World Scientific Series in 20th Century Physics - Vol. 26
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Seminal Papers of Julian Schwinger
Editor
Kimball A Milton
University of Oklahoma
`P World Scientific
Singapore •NewJersey•London *Hong Kong
Published by
World Scientific PublishingCo. Pte. Ltd.
P 0 Box 128, FarrerRoad,Singapore 912805
USA office: Suite 1B, 1060 Main Street, River Edge, NJ 07661
UK office: 57 SheltonStreet, Covent Garden, London WC2H 9HE
The editor and publisher would like to thank the following publishers of the various journals and books for their assistance and permission
to include the selected reprints found in this volume:
Julian Schwinger Papers (Collection 371), Dept. of Special Collections, University Research Library, University of California, Los
Angeles; American Physical Society (Phys. Rev., Phys. Rev. Lett.); AcademicPress(Ann.Phys.);Transactions of the New York Academy
of Sciences; The University of Chicago Press; Proceedings of the National Academy of Sciences USA; CERN; Plenum Publishing
Corporation(Found. Phys.);Brookhaven National Laboratory; American Institute of Physics (Am. J. Phys.);Kluwer Academic Publishers
(Len. Math. Phys.).
British Library Cataloguing-in-Publication Data
A catalogue record for this book is available from the British Library.
A QUANTUM LEGACY
Seminal Papers of Julian Schwinger
Copyright © 2000 by World Scientific Publishing Co. Pte. Ltd.
All rights reserved. This book, or parts thereof may not be reproduced in any form or by any means, electronic or
mechanical, including photocopying, recording or any information storage and retrieval system now known or to be
invented, without written permission from the Publisher.
For photocopying of material in this volume, please pay a copying fee through the Copyright Clearance Center, Inc.,
222 Rosewood Drive, Danvers, MA 01923, USA. In this case permission to photocopy is not required from the
publisher.
ISBN 981-02-4006-6
Printed in Singapore.
To my dear wife, Margarita, who has suffered through my Schwinger projects, yet has
given constant encouragement.
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ix
PREFACE
Julian Schwinger died in July 1994. Within a short time, many of those close to him
were thinking of a suitable memorial to his lifework. A rather obvious one was a companion
volume to the selection of his papers published on the occasion of his 60th birthday.'
A specific proposal was made by Dr. Phua of World Scientific, that a volume be edited
under the leadership of Professor Kenneth Johnson, with subeditors on various subjects.
Unfortunately, little transpired until the idea was revived in 1998. At that time, I agreed
to serve as editor, with Ken Johnson as consultant. Unfortunately, in the summer of that
year, Ken Johnson was taken ill; but he agreed to the choice of papers included here. It
is truly a misfortune that Ken is no longer with us to see the finished product; I hope the
volume serves not only Schwinger's legacy, but Johnson's.
A few words about the selection of papers included here. Schwinger wrote prodigiously
on many topics in theoretical physics, as can be seen by examining the list of his papers
appearing in the Appendix. We decided to include only papers that were not published in
the previous volume.' We have included some of Schwinger's most important and influential
papers, such as `On Gauge Invariance and Vacuum Polarization,' `On Angular Momentum,'
`Theory of Many-Particle Systems,' and `Field Theory Commutators.' We have also in-
cluded two papers that were never published, `On the Interaction of Several Electrons,' a
remarkably mature early treatment of quantum electrodynamics, written when Schwinger
was only 16, and `On Radiation by Electrons in a Betatron,' written in 1945 but very differ-
ent from his 1949 paper on synchrotron radiation. We also have included a few philosophical
talks he gave in various venues.
I begin the volume with an extended synopsis of Schwinger's life and work. This will help
put the papers selected in context. For a more complete treatment, the reader is referred
to a forthcoming scientific biography.2 More technical comments, often including remarks
by Schwinger himself, appear at the beginning of each section of the book, introducing each
group of papers.
Evidently, the present volume must be seen as complementary to the biography,2 and I
must thank Jagdish Mehra for allowing portions of his interview with Schwinger to appear
here. I also must thank the Department of Special Collections, especially Charlotte Brown,
of the University Research Library, University of California, Los Angeles, for graciously'
allowing me access to the Schwinger archive. I am also indebted to many of Schwinger's
students and colleagues for kindly permitting me to interview them.
