杨振宁论文集(1945-1980)Selected Papers.pdf

SELECTED PAPERS(1945-1 980)With Commentary 2005 Edition World Scientific Series in 20th Century Physics Published Vol.20 VOl.21 Vol.22 Vol.23 Vol.24 Vol.25 Vol.26 Vol.27 Vol.28 Vol.29 Vol.30 Vol.31 Vol.32 Vol.33 Vol.35 Vol.36 The Origin of the Third Family edited by 0.Barnabei,L.Maiani,R.A.Ricci and F.R.Monaco Spectroscopy with Coherent Radiation-Selected Papers of Norman F.Ramsey(with Commentary)edited by N.F.Ramsey A Quest for Symmetry-Selected Works of Bunji Sakita edited by K.Kikkawa,M.Virasoro and S.R.Wadia Selected Papers of Kun Huang(with Commentary)edited by 6.-F.Zhu Subnuclear Physics-The First 50 Years:Highlights from Erice to ELN by A.Zichichi edited by 0.Barnabei,P.Pupillo and F.Roversi Monaco 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 A Quantum Legacy-Seminal Papers of Julian Schwinger edited by K.A.Milton Selected Papers of Richard Feynman(with Commentary)edited by L.M.Brown The Legacy of Leon Van Hove edited by A.Giovannini Selected Works of Emil Wolf(with Commentary)edited by E.Wolf Selected Papers of J.Robert Schrieffer-In Celebration of His 70th Birthday edited by N.E.Bonesteel and L.P.Gorkov From the Preshower to the New Technologies for Supercolliders-In Honour of Antonino Zichichi edited by B.H.Wiik,A.Wagner and H.Wenninger In Conclusion-A Collection of Summary Talks in High Energy Physics edited by J.D.Bjorken Formation and Evolution of Black Holes in the Galaxy-Selected Papers with commentary edited by H.A.Bethe,G.E.Brown and C.-H.Lee A Career in Theoretical Physics,2nd Edition by P.W.Anderson Selected Papers(1 945-1 980)with Commentary by Chen Ning Yang For information on Vols.1-20,please visit http:/ World Scientific Series in 20th Century Physics-Vol.36 SELECTED PAPERS(1945-1980)With Commentary 2005 Edition Chen Ning Yang b World Scientific NEW JERSEY-LONDON-SINGAPORE*BElJlNG-SHANGHAI*HONG KONG-TAIPEI-CHENNAI Published in 2005 by World Scientific Publishng Co.Re.Ltd.5 Toh Tuck Link,Singapore 596224 USA office:27 Warren Street,Suite 401-402,Hackensack,NJ 07601 UK ofice:57 Shelton Street,Covent Garden,London WC2H 9HE Library of Congress Cataloging-in-Publication Data Yang,Chen Ning,1922-Selectedpapers,1945-1980,with commentary.Bibliography:p.Includes index.1.Physics-Collected works.2.Yang,Chen Ning,1922-Collected works.I.Title.QC21.2.Y3625 2005 539.7 82-13599 ISBN 981-256-367-9 Copyright 0 Chen Ning Yang All rights reserved.Printed in Singapore by B&.I0 Enterprise Preface to the New Edition Dr K.K.Phua proposed to reprint this book.I think it is a good idea,as it is a record of one persons journey through a very exciting period of physics research after the Second World War.I propose only to add two new items at the end of the book:one a short note written for the book 50 Years of Yang-Mills Theory edited by G.t Hooft(World Scientific,2 0 0 5)and another,an article Remem-bering Robert Mills,published in 2003 in Physics Tody.March 2005 Chen Ning Yang Ji-Bei Hoang B Kai-Qun Lu Professor Tsinghua University,Beijing This page intentionally left blankin the authors ofice at Stony Brook,2 981.The sculpture is by his friend Ping-Ming Hsiung,who is also the calligrapher of the Chinese title on the cover.(Courtesy of Peter Renz.)Preface Some time ago,several colleagues proposed that a festschrift be published for my sixtieth birthday.I thought about it and concluded that a collection of some of my papers with Commentaries might be more interesting.That is the origin of this volume.There was no uniform criterion for deciding which papers to include.Papers that were unpublished before,or had appeared in journals that are not easily available,were given preference.Recent papers in easily available journals were,as a rule,given low priority.The papers are generally labeled according to the year they appeared in print,but a number of exceptions have been made to this rule.The labeling of papers in one year by a,by c,.was mostly by chance.A double bracket indicates that the paper is reprinted in this volume.A single bracket indicates that the paper is not reprinted here.The Commentary is intended primarily to trace my personal development as a physicist and to sort out my interests and ideas starting from my days as a graduate student.It is not meant to be an assessment of my work.No general effort was made to follow up on the developments after the publication of the papers.A scientist is not expected to give a balanced assessment of his papers.But he is the one who knows their stories best:A piece of literature Is meant for the millennium.But its ups and downs are known Already in the authors heart.Ttr Fu,AD 71 2-770 I am grateful to a few close friends who have given me valuable advice and criticism.For her help in preparing the manuscript,I am indebted to Catherine Turpin.Special thanks are owed my friend Ping-Ming Hsiung for his calligraphy on the cover.October 1982 Chen Ning Yang Stony Brook,New Y