If you google 英语摘要的时态， you will see use the past tense. (网上搜索，你会看到“摘要应该用过去时”。） If you never wrote a paper on your own, you may take this as the truth and follow it faithfully. But, I have to say this rule needs to be relaxed. Here is why. （但是，摘要不一定非用过去时哦。） I am an ocean modeler, and used to write papers on basic physics related to ocean dynamics. I never used the past tense in my own abstracts, never. Instead, I used the present tense. (Oh, in case you don't know my work, all my papers were published in good journals in the field.) Why? This is because these papers are about basic physics, and the results remain true if one repeats these numerical experiments (at least I hope so :) So, now you know at least there are two ways to write an abstract: the past tense, and the present tense. （摘要可以用过去时，也可用现在时。） In fact, you cannot use the past tense if you want to end the abstract like this: This new method has great potenial in xxx application. (有时你不能用过去时，比如谈论一个新方法的应用。） The best way to decide which tense to use is to read your colleagues' papers and to check out journal's requirements (under guidelines for authors).（最好的办法是看看你的同行怎么写摘要、看看期刊是怎么要求的。） One more thing, to end the abstract with the potential impact of some of your new findings, you have to use the present tense, I think. (Now, you see where I stand.) （显然，有时你只能用现在时。） For example: This new method may have potential application in identifying new species. I also find this link useful for Chinese authors: http://www.xuebao.tyut.edu.cn/webpage/EI.htm
ICM: The Interdisciplinary Contest in Modeling ICM今天截止。我的朋友事先打了招呼，让我帮忙改摘要，一共15份。没有想到，这些摘要多是在最后几个小时送给我的。亚历山大。从8 am 一直忙到快1 pm，终于改完了。 Let's wish these students good luck!
http://www.latex-community.org/viewtopic.php?f=47t=3649 \ documentclass { article } \begin { document } \begin { abstract } \ vspace * { -.5em } text text text text text \end { abstract } \end { document } Note: if use \input{abstract}, and in the separated file use \vspace*{}, it doesn't work.
Abstract is very important for a paper. Readers may first read the abstract and then decide whether they'll continue to read the whole paper. When we invite the reviewers, we only send the abstract to them and wait for their reply. If the reviewers read a badly-written abstract, then he will directly decline the review invitation, and some of them will write to the editors, after a quick look at the abstract, I think this paper has no novelty. The absract makes me stop looking down for the rest of this paper. But abstract is very difficult to write well. Abstract is the mini-version of the fulltext. It should inlcude the research objective, materials and methods, the major and important results, and then a conclusion. Authors should first write the full text and then write the abstract. Jargons should be avoided. Reference should not to be included. Acronyms should only follow the fullname or be followed by the explanation. E quations or formulars are better to be avoided (they can be explained in words ) Should we use Active voice or Passive voice in the abstract? Try to use active voice if you can express well in active voice. Should we use past tense or present tense in the abstract? Use past tense to descibe the experimental process and use present tense to descibe the methods and results. ....................... Here, I recommended one very useful Link. Writing the Abstract http://www2.plymouth.ac.uk/millbrook/rsources/litrev/lrabstract.htm
For the first time, I declined to review a manuscript for a journal, based on its abstract. I read the abstract yesterday, and decided to do nothing. I was working on a paper, and thought that I would sit on this decision for a day even though I didn't like what I read in the abstract. Today, I didn't have much to do with papers, so I wrote a Blog in Chinese, which probably took me more than one hour (not that I wrote a long article; I am just very slow at writing/typing in Chinese). By late afternoon, I decided to do something about this invitation (to review a manuscript). I read the abstract once more, and clicked decline. I made this decision based on my own experience on dissolved oxygen concentrations in the northern Indian Ocean.
My name is Li , I was born in W ， H province. I received both my Master and PhD degree at Resources and Environment College of China Agricultural University advised by my advisor Dr. S . The research topic for my master degree was land use and information technology . Later on, I turned my topic to land resource management as my advisor transferred to another department, however, my research still focused on Remote sensing applications . My Master’s thesis topic is about analyzing and Validating the regional leaf area index inverted by PROSAIL based on remote sensing , and my PhD’s thesis is about monitoring of the dynamic soil heavy metals pollution of large area by using the combination of Remote sensing inversion and Complex network theory , which is technically supporting environmental risk assessment of regional soil heavy metals pollution. I have earned my master degree and continued on my PhD research with two year working experience as well since 2006. During more than six years , I have participated in six important projects, and was responsible for two major projects’ secondary research. I have published six papers as first author, and three papers as second author. Therefore, I could understand the process of project operation, including pre-demand research and argumentation, interim execution , and late finishing. Furthermore, I am capable of good communication and teamwork skills. I have been participated in preparing application statement, mission statement, research report and relevant paperwork for the projects for multiple times . I am well-equipped with a solid basic of remote sensing and geographic information science theory by both courses learning and professional practice . Moreover, I am proficient with scientific algorithm by rapid development languages, such as IDL and MATLAB. I really enjoy the relaxed atmospheres in the institutions , because I appreciate the devoted and pragmatic research style of each researcher and I also admire the honesty and integrity of each researcher as well. So, I am looking forward to devote myself to such an institute with mental and physical pleasure, and also feel motivated to continue my scientific career. Thanks for considering me as a candidate for this job position. I will be very appreciated if you can offer me this working opportunity. Thanks again. With rapid growth of population, urbanization and industrialization, soil, as one of the indispensible natural resources for human beings, is under increasingly environmental pressure and the soil pollution issue has become more and more serious. Heavy metal pollution, among other soil pollutions, with its strong toxic and non-biodegradable characteristics, has become the hot topic of environmental pollution issues globally. Thus, soil heavy metals pollution poses serious threat to the farmland soil-crop system, and the health and safety of farmland environment, which is directly related to the safety of people’s lives and harmony of entire society. The traditional method is undesirable in regional survey because the traditional survey methodology of soil pollution is destructive, not real-time, not accurate, and not quick enough, which makes the traditional methodology is not conducive to the timely detection of soil heavy meals contamination and taking appropriate action on it. Therefore, remote sensing technology is becoming an alternative, effective monitoring method due to its fast, simple and non-destructive merits. In addition, the spatial distribution of soil heavy metal, as one of the soil chemical properties, is becoming increasingly complex and non-normal distributed under the strong disturbance of regional land-use by human. Nevertheless, complex network, as an important theoretical method for complex system research in the real world, is able to describe the behavior and relationship of the individuals in system by using graphic language and quantitative indicators. Thus, complex network theory is a new method to quantify the spatial Pattern of regional soil heavy metal. So, this paper explores the spatial patterns of soil heavy metals based on the complex network theory, and monitors soil heavy metals content by using remote sensing technology. Based on the discussion above, the author takes Beijing agricultural soil as an example, the concentration of soil heavy metals including Cr, Ni, Cu, Zn, As, Cd, Pb, and Hg were analyzed, and spectral data of treated soil samples were measured inside of the lab. The author calculated the characteristic spectrum of soil heavy metals by using spectral analysis method, which is the basis for later remote sensing monitoring; the author also revealed the potential pollution resources via BP neural network, and combined complex network theory and spatial autocorrelation theory to analyze the space network pattern of soil heavy metals which is non-normal distributed.
http://www.chemistryviews.org/details/education/2709521/Tips_for_Writing_Better_Science_Papers_Abstract_3.html Have you ever struggled to write up your results into a publishable paper only to get it rejected? Richard Threlfall, Managing Editor, Asian Journal of Organic Chemistry , gives some insider tips on how to improve each section of your article and increase your chances of getting published. Abstract Imagine you have twenty seconds to explain the project you have been working on for months or years to another scientist who is not familiar with your area of research. You would probably try and tell them the one or two main outcomes without going into excessive technical detail. This is a good way to think about writing your abstract! The abstract is only short, but that doesn't mean that you have to cram as much detail into it as possible. What you want is to grab the reader's attention with the first statement, add a few of the most important details, then leave them with the overall message of the manuscript in the last sentence. In this way it is similar to a news article. Have a look at some articles in a newspaper. Most often the first sentence contains the crucial information about the story and then the details follow after that. This is a good model for your abstract; after all, what you're writing is news for the scientific community. Electronic search engines and indexing services will often only search abstracts when performing word-based searches, and the abstract is frequently the first thing that is displayed when your manuscript appears in searches. From this point of view, you should make sure that there are several keywords in the abstract as well as the title (see our earlier " Titles " section for more about keywords) to give your manuscript the best chance of being found by a search. A good abstract is concise, explains the main findings of the research, but does not overwhelm the reader with technicalities—you want the reader to be interested enough to read the whole paper, where they can find the technical details themselves. Good abstract writing is a key skill for scientists, as it is also necessary for conferences, grant proposals, and job interviews, so take your time and really think about how to make an impact.
《柳叶刀》11月10日在线发表的一项研究表明，一些从行为学角度被诊断为植物状态的病人，可能还会存留部分意识和认知功能。请看该论文摘要。 http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(11)61224-5/abstract Bedside detection of awareness in the vegetative state: a cohort study Original Text Dr Damian Cruse PhD a b , Srivas Chennu PhD c , Camille Chatelle MSc d , Tristan A Bekinschtein PhD b , Davinia Fernández-Espejo PhD a , Prof John D Pickard MD e , Prof Steven Laureys MD d , Prof Adrian M Owen PhD a b Summary Background Patients diagnosed as vegetative have periods of wakefulness, but seem to be unaware of themselves or their environment. Although functional MRI (fMRI) studies have shown that some of these patients are consciously aware, issues of expense and accessibility preclude the use of fMRI assessment in most of these individuals. We aimed to assess bedside detection of awareness with an electroencephalography (EEG) technique in patients in the vegetative state. Methods This study was undertaken at two European centres. We recruited patients with traumatic brain injury and non-traumatic brain injury who met the Coma Recovery Scale-Revised definition of vegetative state. We developed a novel EEG task involving motor imagery to detect command-following—a universally accepted clinical indicator of awareness—in the absence of overt behaviour. Patients completed the task in which they were required to imagine movements of their right-hand and toes to command. We analysed the command-specific EEG responses of each patient for robust evidence of appropriate, consistent, and statistically reliable markers of motor imagery, similar to those noted in healthy, conscious controls. Findings We assessed 16 patients diagnosed in the vegetative state, and 12 healthy controls. Three (19%) of 16 patients could repeatedly and reliably generate appropriate EEG responses to two distinct commands, despite being behaviourally entirely unresponsive (classification accuracy 61—78%). We noted no significant relation between patients' clinical histories (age, time since injury, cause, and behavioural score) and their ability to follow commands. When separated according to cause, two (20%) of the five traumatic and one (9%) of the 11 non-traumatic patients were able to successfully complete this task. Interpretation Despite rigorous clinical assessment, many patients in the vegetative state are misdiagnosed. The EEG method that we developed is cheap, portable, widely available, and objective. It could allow the widespread use of this bedside technique for the rediagnosis of patients who behaviourally seem to be entirely vegetative, but who might have residual cognitive function and conscious awareness. Funding Medical Research Council, James S McDonnell Foundation, Canada Excellence Research Chairs Program, European Commission, Fonds de la Recherche Scientifique, Mind Science Foundation, Belgian French-Speaking Community Concerted Research Action, University Hospital of Liège, University of Liège.
The Society For Biomaterials 2013 Annual Meeting website, and abstract submission portals, are now available at: http://2013.biomaterials.org/! The 2013 Annual Meeting will take place at the John B. Hynes Veterans Memorial Convention Center in Boston Massachusetts, April 10-13, 2013. A complete list of proposed sessions http://2013.biomaterials.org/content/proposed-sessions-0 for which abstracts are being requested are also listed there. The abstract submission deadline is November 30, 2012.
In November 1973 the UCLA Monthly , a periodical for faculty and students of the University of California at Los Angeles (UCLA), published an interview with Julian Schwinger. Since the interview reveals many of Schwinger's views about science and society, which he seldom shared with the public, this final chapter begins by quoting the interview, conducted by Mark Davidson. Among the topics he addressed were whether he thinks scientists are sufficiently concerned about the moral implications of their work, Albert Einstein's contention that man's way of thinking must change, whether scientists he met in various countries tend to think like citizens of the world, and his reputation as a public crusader. This chapter also looks at Schwinger's interest in music and composition, sports, reading, cats, and travel. Schwinger's tributes to fellow physicists Sin-itiro Tomonaga, who died in 1979, and Richard Feynman, who died in 1988, are also presented. Tomonaga and Feynman were his co-recipients of the Nobel Prize for Physics in 1965 for their formulation of renormalised quantum electrodynamics. Keywords: Richard Feynman , Sin-itiro Tomonaga , interview , music , sports , quantum electrodynamics Confessions of a nature worshipper In November 1973 the UCLA Monthly , a periodical for faculty and students of UCLA, published an interview with their newly acquired Nobelist. 1 Since this reveals many of Julian Schwinger’s views about science and society, which he seldom shared with the public, it seems appropriate to begin this final chapter by quoting the interview. The questioner was Mark Davidson. Do you think scientists are sufficiently concerned about the moral implications of their work? ‘The establishment of the American Federation of Scientists and other such groups is a direct reflection of the scientists’ moral and practical concern with the application of their developments. All of this followed the development of the atomic bomb, which was of course the major traumatic experience. ‘But at the same time scientists tend to feel that society should not impose any restrictions on the purely research aspects of their work. We feel the scientists should be free to extend the boundaries of man’s knowledge no matter where that search leads. How the results of our work are applied then becomes a serious moral question in which all of society should be involved. ‘If a chemist, for example, were to discover a gas which might be used for chemical warfare, I do not believe he should then destroy the knowledge of that gas. He should try to make sure it is never used for that purpose. But that’s not a question of suppressing the research. It’s a matter of changing the whole way of thinking of the people involved in deciding how scientific discoveries are applied.’ Einstein once wrote that the atomic bomb had changed everything but man’s way of thinking, and that must change. In what ways do you think man’s thinking must change? ‘Einstein meant that war as a means of deciding questions must be abandoned. And I fully believe, in spite of everything one sees in the newspapers, that man is moving in that direction. (p. 568 ) ‘For example, there was the widespread revulsion against the Vietnam episode. And the gradual inchings toward East–West detente is a hopeful sign. Let’s hope the atomic bomb, if it prompted this global trend, will turn out to have been a blessing in disguise.’ Einstein also wrote that the abolition of war would require the evolution of a patriotism toward the entire human race. Is that your thinking too? ‘Yes. And that’s one of the reasons I’m very partial toward the space program. Some scientists rail against the supposed wasting of money on space. But the space program has helped to remove the parochialism of the human race. When man can go up there and look down and see how tiny our sphere is and how we really are all just one people, I think the national barriers and narrow ways of thinking tend to disappear. In that sense I think science may have contributed an enormous step toward making us one people.’ Do the scientists you’ve met in various countries tend to think like citizens of the world? ‘Yes, and that’s very understandable. The scientific attitude toward things is a dispassionate weighing of facts and the removal as far as possible of emotionalism and irrational attitudes. And when you’ve done that, there’s very little room for nationalism and the rest of the petty ideas.’ Have you met such cosmopolitan ideas in the Communist world? ‘Yes. I spent a month or so in the Soviet Union once and I talked to people there who were hardly distinguishable from Western scientists.’ As a member of the international scientific community, do you feel a kinship with Soviet physicist Andrei Sakharov, who has become a symbol of the fight for intellectual freedom in the Soviet Union? ‘Very much so. And I must agree with him that we in America should help open up that society by asking for intellectual freedom as a bargaining point in the negotiations for a lasting detente. As a member of the National Academy of Sciences, I was delighted with its recent resolution to that effect.’ You don’t have a reputation as a public crusader, do you? ‘Well, I’m not really a great signer of resolutions. * I’m a member of the American Civil Liberties Union and I’m on the board of sponsors of the Bulletin of the Atomic Scientists . But I’m a retiring sort of person who does not enjoy broadcasting his views. My views are readily available to anyone who wants to ask, as you are.’ Do you ever have occasion to discuss your social views with students? ‘That does happen sometimes. Recently I had what I suppose was a rap session with some of my physics students. And they seemed to share many of the views I’ve been discussing with you.’ (p. 569 ) Speaking of students, how old a student were you when you decided to become a scientist? ‘Oh, I think I was about 10 when I decided to become an engineer.’ You’re not the son of a scientist, are you? ‘No. My father was a designer of ladies’ clothes. But I became very interested in science while I was in grade school in New York City. And the most immediate thing was engineering, so I said, gee, I want to be an engineer. Then, as a result of reading books in the public library, I discovered that the really interesting thing about engineering was the science behind it. And so I probably was about 12 when I decided to become a physicist.’ And you became a Columbia Ph.D. in physics by age 21 and a full professor in your field at Harvard by age 29. What attracted you to theoretical physics? ‘I became fascinated with the structure of the universe.’ Can your fascination be described as religious? ‘I suppose it’s a form of nature worship. Perhaps it’s not that much removed from the worship of a rock or a tree. Whatever directed primitive man to stand and wonder at the heavens is still at work in modern science.’ Has your awe of the universe increased over the years? ‘Awe is indeed the word. And the feeling has increased as I’ve learned more about the complexity and yet simplicity of the universe.’ Perhaps this is an unscientific question, but do you foresee an end to discoveries about the nature of matter? ‘That’s actually a very good question. I think my answer is no. I don’t see an end. It’s hard to say why. Perhaps one reason is that to believe we’re nearing the end of this discovery would be a form of unacceptable arrogance. ‘It would be arrogant to assume that in roughly 300 years of modern science we could approach anything like an understanding of the mystery of what’s out there. ‘In recent years we’ve become aware of so many new facets of nature that were totally unexpected, such as quasars, neutron stars, and black holes. Perhaps when we travel to other planetary systems, we’ll discover things that are simply unimaginable. ‘So we’re not even near the end of discovery. I think we’re at the beginning.’ What about the possibility of intelligence on other planets? ‘I’d be extremely shocked if we didn’t have myriads of cousins out there somewhere. It seems very reasonable that if the laws of nature are the same almost everywhere, then what happened here would happen elsewhere. I do believe there is intelligence throughout the universe. And I would devoutly wish that in my lifetime the first meeting would take place.’ Have you been involved in the controversy about the value of basic research as compared with applied science? ‘As a theoretical physicist, I’ve typically been asked by reporters, what good is your work?’ (p. 570 ) How do you answer such an irritating question — other than by resorting to violence? ‘Well, violence is often indicated but never applied. I’m afraid I answer in the usual general terms: one does basic research because it’s in the nature of man to seek understanding. Fundamental research does pay off in practical applications, but that should never be the sole justification.’ Nevertheless, the basic research for which you and two other scientists received the Nobel Prize in 1965 did lead to practical applications … ‘The prize was awarded for research we had done many years before on quantum electrodynamics, which probably influenced the climate of the applied work that resulted in the invention of the laser. And somewhat earlier, I made direct use of my theoretical knowledge of electromagnetic waves to help develop radar.’ Do you think the press has been making any constructive attempts to educate the public about the value of basic research? ‘There are many more science editors today than there used to be. I’m not sure they are that proficient in science, but they try. ‘I think the great tragedy has been that our government has never understood the importance of fundamental research. Government in general has gone along with science only because of its practical applications. But the idea of science for the sake of science has certainly never been appreciated.’ Is there a needy do you think, for more public understanding about the controversy over the federal cutback of funds for basic science? ‘Very much so.’ Scientists at UCLA and elsewhere have referred to this situation as a national crisis. Do you agree? ‘I think it’s a crisis. Suppose we do say yes applications are important and that government should focus primarily on applications. We’ll accept that, but applications are always the consequences of fundamental research that was done years earlier. ‘When you destroy the broad base of research, the repercussions will go on for many years.’ How do you respond to the argument that research at a university tends to detract from teaching? ‘It’s been my experience that research and teaching go hand in hand. ‘My research has always been enormously assisted by the fact that I had a crew of warm bodies and live minds on whom to try out new ideas. Conversely, the viable parts of that research were instantly incorporated into the things I talked about in class.’ Do you think there should be more instruction about the revelations of basic science in liberal arts curricula? ‘Absolutely. Science should be a central point of liberal arts education. ‘In fact, what could be more of a liberal art than science? I hope I’ve conveyed to you my feeling of the tremendous excitement that goes with this endeavor. (p. 571 ) ‘There’s no need for liberal arts students and other laymen to view science as mechanical and uninspiring when in fact it’s more artistic than art and more religious than religion. It has in it the best of everything that man has achieved.’ ‘I will be a composer by the time I’m 30!’ Music was important to Julian Schwinger throughout his life. While Julian was at Townsend Harris High School, or perhaps just after he entered City College, he fell under the influence of Hyman Goldsmith. As we have mentioned in Chapter 1 , he was instrumental in kindling Schwinger’s interest in classical music. Bernard Feld recalled that ‘Hy was a dilettante and he was a very interesting guy because he was very lazy. But on the other hand, he had two things—one, he had an encyclopedic knowledge of what was going on, and he had really good taste. He knew what was important and what wasn’t important.’ 3 He had a great interest in music, and this had a profound influence on Julian. 4 Herman Feshbach first met Julian about 1935, while he was still a student at City College, and kept in touch with him when he went to Columbia. He recalled that a group of young physicists, including Julian, would meet at the home of Artie Levinson and listen to music. A favorite opera of Julian at the late 1930s soirees was Mozart’s The Marriage of Figaro . 5 Joseph Weinberg, his friend at City College, recalled that Julian was exclusively interested in Mozart there, as later at Berkeley. Weinberg tried to interest him in Beethoven, particularly the F major quartet, opus 135, without much success. Julian was mystified by Weinberg’s enthusiasm for Bach. Weinberg recalled looking at his record collection at Berkeley, which he did not find very exciting, except for the Mozart C major quartet, K465, ‘The Dissonant.’ When Weinberg picked out that piece, Julian expressed surprise, because apparently Oppenheimer had selected the same piece of music earlier. 6 Julian Schwinger was close to Nathan Marcuvitz at the Radiation Laboratory, and in the immediate post-war period; indeed, as we have mentioned earlier, it was Mark who introduced Clarice and Julian. Marcuvitz recalled how Julian loved music, and often had a radio on in the lab. At one point he told Marcuvitz that ‘at age 30 he would quit physics and devote himself to musical composition.’ 7 David Saxon, another close co-worker and friend at MIT during the war remembered that ‘he came to my house many times to listen to chamber music.’ 8 Clarice recalled that when they first started dating she became aware of his interest in music. Julian enjoyed music and they went to symphonies sometimes. 9 In the early years of their marriage, Julian and Clarice went to concerts and the theater. ‘It did tend to diminish over the years. I’m not sure why. Maybe it just got physically harder, to find parking places,…. I did take (p. 572 ) up playing the piano, which I never mastered but always enjoyed. I think Clarice had a friend who sort of took me in hand and taught me the notes. I think I had a few private teachers with whom I didn’t do very well because I got nervous under such close supervision. My music never amounted to anything, but I was willing to tackle anything no matter how bad my production of the sound was, because in my mind I could hear the way it was supposed to sound. I borrowed the quotation, “Anything worth doing is worth doing badly,” from somebody else. That is something I subscribe to in all areas but one.’ 4 It was impossible for Julian to go to a concert the evening before he had a class, because he always needed that time to prepare. In those days there were Tuesday night concerts at Sanders Hall of the Boston Symphony to which Julian and Clarice subscribed. But Julian had a class on Wednesdays. He found it difficult to go out on Tuesdays, so Roy Glauber would often escort Clarice to these concerts. 9 And then somebody told Clarice that people were talking because Roy and Clarice were going to these concerts. So they were forced to stop attending the series. 9 Julian noted that one of Clarice’s old friends, Rhody Abrams, initiated his musical studies. It was Rhody who taught him how to read music on the piano. And it was through her that Julian got the two teachers that he had. The first one was from the New England Conservatory of Music; he started him out on scales, and he found that difficult and did not enjoy it. Julian did not really want to be a pianist; he just wanted to be able to play. So they found a teacher from the Longy School in Cambridge 10 who taught Julian to sight read. That was a great success. As a result, he could play anything, for better or worse, never counting. Sometimes he would play quite well and other times not so well. Earlier he had played every night before he went to bed, but in later years he stopped doing that. 9 Clarice recalled that people would hear Julian playing while they were conversing with her on the telephone, and would ask who was playing. When they would come for dinner, they would ask Julian to play. Clarice would tell them to make that request while on the phone, for he sounded much better on that medium. Julian would never perform in public. 10 Not all their friends shared their interest in classical music. John Van Vleck was a very good friend. Although he thought he was typically American, Clarice felt that nobody could be less typical. His background was special, he was gentlemanly, and, of course, very bright. He was intellectual, but not in music; his taste ran to band music. Clarice recalled the first time he came to dinner, without his wife. After dinner they went to the living room and he played band music. The Schwingers almost went out of their minds, in spite of it being good band music. Clarice was more responsive than Julian. 9 Clarice, however, remembered that Julian was knowledgeable about popular music. Although he did not like jazz and rock and roll, he knew the names of all the performers. 10 (p. 573 ) Tennis, skiing, and swimming An early indication of Schwinger’s interest in sports was manifested by the childhood episode when Julian was at summer camp in the Adirondacks. When Julian caught the ball hit by a visiting tennis pro, Bill Tilden, he was informed that he would go far, which the boy interpreted as meaning in the tennis world. At that same camp, where his older brother Harold was a counselor, Julian learned to swim. As a student, Schwinger was not interested in contact sports. He recalled, ‘When I got to Columbia they had a requirement for physical education, and that meant several things. You had to swim the pool several times, which I managed to do. But you also had to come out for things like wrestling; and the wrestling was that you were put on a mat and somebody who was really a wrestler would come running at you. And you were supposed to do something. Well, I, instead of opposing him, just skipped nimbly out of the way and he landed outside the mat. He got up and looked at me strangely and tried it again. I was in no way interested in contact. I thought my wits were better.’ 4 Schwinger had enjoyed music with Hyman Goldsmith. We recall that one time Goldsmith took Julian along for a game of tennis: because he had not played tennis for several years, his initial attempt to hit the ball was a spectacular failure, at which point Goldsmith took the racket away from him, much to Julian’s annoyance, who felt, if given a chance, he could play quite decently. 4 Saxon also remembered being surprised at Schwinger’s athletic interests and abilities at MIT during the war. When they would have a picnic, he could throw a football well, and seemed to have normal athletic interests which no one would have expected from his demeanor in the laboratory. 8 Schwinger’s secret athletic prowess continued when he became a faculty member at Harvard. Charles Zemach, who was nominally Schwinger’s graduate student in the early 1950s, but really wrote his thesis under Roy Glauber’s direction, recalled that the physics graduate students used to have an annual picnic at Professor Benfield’s farm. Julian was always personally invited, but never came. But one year, the president of the physics club invited Clarice, so the Schwingers went. A baseball game ensued; everyone was astounded, because Julian ‘was a tremendous slugger, he really powdered the ball.’ 11 Tennis became a passion with Julian in the 1960s. While still at Harvard, he took on a student Asim Yildiz, a former member of the Turkish national team, who became his tennis instructor. Once settled in California, his regular tennis partner was Lester DeRaad, Jr, who had been his student at Harvard, and had accompanied him on his move to UCLA as a postdoctoral associate. Their playing continued well into the 1990s. (p. 574 ) A unique perspective on this interest was provided by Ian Rosenbloom, who then worked with the BBC as a producer for the Open University program Understanding Space and Time , which we have described in Chapter 14 . He recalled that Julian was very ‘keen in getting as much tennis practice as he could,’ and agreed to teach Rosenbloom physics in exchange for tennis. They mostly played together in California during Rosenbloom’s several trips there during the 1976–77 period. Although Schwinger had ‘an awkward stance, and didn’t look like a challenging’ player, Rosenbloom was always surprised how challenging the matches were. Julian displayed ‘tenacity, determination, and absolute perfectionism.’ 12 In the 1970s and 1980s Schwinger visited Tubingen several times, where he often played tennis with Walter Dittrich. Often these games constituted the bulk of Schwinger’s interaction with Dittrich, who would have liked to have had more opportunity to discuss physics with him. 13 The love of swimming stayed with Julian throughout his life. One of the impetuses for moving to Southern California was the possibility of daily swimming, and indeed at their house in Bel Air the Schwingers had their own pool. In fact, swimming may have been decisive in causing him to move to California: several of his Harvard colleagues believe that his doctor recommended daily swimming as exercise, a prescription nearly impossible of fulfillment in New England. 14 , 15 Julian took up skiing in 1960, on a visit to New Hampshire. We have described this experience earlier. As with music, he tended to resist lessons, so he was largely self-taught. He became quite a competent skier, and skied often in the winters, especially after they moved to California. A reader, a listener, and a cat lover Schwinger was an ‘omnivorous reader.’ His favorite reading was ‘novels of the escapist variety,’ and he became particularly fond of science fiction. Among the authors he enjoyed in the 1980s were Arthur C. Clarke, Roger Zelazny, Fredrik Pohl, Ray Bradbury, and John Brunner. ‘There’s nobody I’m crazy about, but I will sometimes respond or sometimes I go on a run of new authors and go through a whole list. Whatever is current I will read. I insist on only one thing, there is science fiction which begins with a scientific concept and extrapolates it into the future. Total fantasy, I’m not interested. Absolutely hogwash.’ 4 At social gatherings Julian was famous for truly listening to people. He was especially adept at attending to children. Clarice recalled that one of the nicest compliments that Julian ever got was from her niece, who as a little girl was asked why she loved Julian. She replied that she loved him because he listened. 9 Another anecdote refers to a dinner party given by Alfredo and Alice Baños. Diane Anthony, Alice’s daughter, recalled Julian’s kindness and amazing social (p. 575 ) grace in that setting. Julian was seated next to Diane’s son Lao Anthony, an adolescent jazz musician. An awkward teenager, the boy sat slouched, uncommunicative. Julian leaned over and said, ‘I see you’re a lefty like me.’ The boy was shy, but loved to talk about his music. Julian finally got him out of his shell by asking him ‘What is Thelonious Monk’s middle name?’ Lao then sat up and joined the conversation. 16 Julian always loved cats. While he worked at the Radiation Lab at MIT during the war, a cat roamed the premises, and he would sometimes buy two chicken sandwiches, one for himself and one for the cat. 9 After Julian and Clarice were married, a cat quickly entered the picture. His mother would not allow him to have a cat, so on their very first Christmas, Julian bought Clarice a kitten. Clarice remembered opening the big beveled glass door to their house, and seeing Julian’s face framed in the glass with this little grey kitten. It was their cat Galileo, which they had for 14 years. When his mother came to visit, they would lock the cat in Clarice’s mother’s bedroom; if the cat entered the room while his mother was there, she would have a fit. 9 In California, the Schwingers no longer kept a cat. They had an outdoor cat when they first moved to California, but it got eaten by a coyote. Clarice could no longer face the idea of a litter box; and moreover, indoor cats always want to go out. She recalled that Leo (Galileo) was a house cat. When they were not at home in their duplex in Cambridge, if he heard someone open the downstairs door he would tear down the stairs to get out. He wanted out in the worst way. He did not understand that he was not supposed to want out. As a result, sometimes Julian and Clarice were scouring the streets at 3:00 in the morning with a flashlight, calling for Leo, because they were terrified that he had no idea how to take care of himself. Furthermore, he tended to eat everything in sight and then get sick when he got home. But they thought he was a marvelous cat. 9 The cat was really Julian’s. Clarice brushed him and fed him, but he would curl up on Julian’s desk, so while he was working, all Julian would have to do was to put out a hand and pet him to get a purr to come. Galileo and Julian were made for each other. In spite of Julian’s love of a cat, Clarice could not face the thought of losing one again. 9 In view of her own miscarriages, this fear of loss of a child-substitute is quite understandable. Schwinger was not active in politics, yet he was passionate about the issues of the day. He was clearly of the liberal persuasion, and was appalled by the Communist witch-hunt of the McCarthy era. The Oppenheimer hearing, which ultimately cost J. Robert Oppenheimer his security clearance and his access to the highest levels of the government, troubled Julian greatly. Apart from thinking absurd and outrageous, I didn’t have much of an opinion.’ 4 Yet, although always impressed by Oppenheimer’s intellect, he saw all too clearly Oppenheimer’s character flaws. At one point, due to Julian’s close relationship (p. 576 ) to Oppenheimer, a television interview with Eric Severeid was arranged. A film crew came to the Schwingers’ house on two occasions and interviewed Schwinger. Yet, for a variety of reasons, that interview was never aired. 2 ‘Nobody ever thought, for example, of subpoenaing me. In fact, the nearest approach to it came when some television crew showed up in my house and said, “would you make a statement?” I had thirty seconds to say something and I’m sure I described as quite outrageous, or whatever, and then discovered afterwards that something had gone wrong and that film never existed. So even that little contribution did not come about.’ 4 Schwinger clearly saw Teller’s motivation for removing Oppenheimer from a position of authority. * ‘From my own point of view, after all, my reluctance to become involved in the atomic bomb project in the first place would certainly extend into the reluctance to favor the development of future nastier bombs, which of course was also Oppenheimer’s presumably principal sin, to stand in the way of the hydrogen bomb. His association, second-hand or whatever, with the Communist Party, all of this was old hat and to drag it out again was really just a flimsy excuse. That he outsmarted himself by being a little too ambiguous on some occasions was of course a problem.’ 4 Traveling in style Julian and Clarice’s first trip together was their two- or three-month honeymoon vacation to the West. One of the stops was Los Alamos. There Julian was asked to give a talk at what they considered the ungodly hour of 8:00 a.m.; remarkably, Julian agreed, to Clarice’s consternation. They went down to Santa Fe to buy an alarm clock. That morning, outside La Fonda, they heard a man said, ‘Hello, Julie.’ Clarice did not know who ‘Julie’ was. It never occurred to her to call Julian ‘Julie.’ Of course, it turned out that those who knew Julian in the Berkeley days called him Julie. Thus, old friends like Bob and Jane Wilson and Bob and Charlotte Serber would have called him Julie; in this case it was Bob Wilson. 9 The alarm clock was a failure: the clock began in their room but it kept Julian awake so they moved it from between the beds to the doorway on a chair under a pillow but he could still hear it. Finally, they moved it out to the living room. They never slept that night. They waited all night for 7:00 a.m. to come; when he went to gave his talk at 8:00. 9 We have already recounted the Schwingers’ first trip to Europe in 1949. That was a palate-awakening trip for Julian. He also enjoyed luxury hotels there, so much so that in Florence they ran out of money and had to call Clarice’s (p. 577 ) mother to wire additional funds when the prize money from the Charles L. Mayer Nature of Light award ran out. Clarice recalled Julian’s first reaction to Paris. Although she enjoyed it, Julian absolutely capitulated when he first set foot in Paris. It did not particularly mean anything to Clarice, but Julian adored Paris always. 9 He would walk everywhere in Paris, while at home he always drove. From Paris, they went to Switzerland to see Pauli, and then to participate in the first half of the joint Swiss-Italian meeting. In Switzerland, Clarice remembered being taken on outings during the meetings; Clarice became rather bored with the routine. She recalled with amusement a picnic outing in the mountains, where a pretty young wife from MIT came overdressed in veil and high heels, ‘straight out of Vogue . At the time Clarice thought she was being pretentious, but in fact she had not known of this organized event for the wives when she returned from a (rather formal) errand. 9 On returning from this trip, Clarice and Julian fell into a comfortable routine. It was a wonderful time for both of them. When Clarice married Julian she hardly knew what a physicist was and she certainly did not know there were two kinds, theoretical and experimental. She felt lucky to have married a theorist. Liza Feld was married to an experimentalist, Bernard Feld, and it seemed to Clarice that no sooner had they gotten into bed and fallen asleep than the telephone would ring with the news that the machine was broken and he’d have to go off to MIT to fix it, or they would go to sleep and his colleagues would wake him and say the machine is working and he had to go off to do the experiment. People asked Clarice how she could stand to have Julian at home all the time. In Clarice’s view, it was much easier to have him home all the time than to have him go off in the middle of the night. That would have been as bad as being a medical doctor’s wife, which Clarice would not have liked at all. 9 This was the first of many trips to Europe. For example, in 1955, they went to Pisa, to the Scoula Normale there, where Julian attended a meeting. That was the summer they also spent three weeks at Les Houches, where Schwinger gave his famous lectures on quantum mechanics. They had to travel there first-class, on the S.S. Flandre , a one-class ship. His schedule at Harvard and the time they had to be at Les Houches was such that there were no other ships that would get them there on time. So they went first-class. Clarice recalled seeing Julian at the dinner table. It was indescribable. The last dinner on board ship, he ate everything in sight. He paid for his gourmet experience by having a very unhappy night. 9 Clarice found it to be very frustrating to be at Les Houches. On their side of the mountain it was raining constantly, whereas across the way the Sun was out. They were on the wrong side of the mountain, but they had a very good time. There they discovered palmier , what are called elephant ears in the United (p. 578 ) States, because, once again, they were certainly never going to get up in time for breakfast. They would go into the little town and buy them. They had a kitchen in the building where they stayed, so Clarice would fix palmier and coffee for breakfast and then they would slide down the hill for lunch. 9 Following the summer school they went to Denmark. Clarice found the drive through Germany terrible. It filled her with horror. Although the weather was beautiful and they were driving down a lovely road, with beautiful trees in the sun, she imagined seeing truckloads of people being sent off to concentration camps. It was a hideous time for her. 9 The visit in Copenhagen was arranged by Stanley Deser, who was doing a stint as a postdoc there. We described that trip in some detail in Chapter 10 . ‘1955 stands out in my memory as an absolutely gorgeous summer spent covering as much of Europe as we could.’ 4 In 1958 they again spent the summer in Europe, eventually attending the High Energy Conference at CERN, where Julian had a heated exchange with Pauli over Euclidean field theory. In 1959 they attended the same conference in Kiev, and returned from Russia via Helsinki, which they found enchanting. Julian’s and Clarice’s vivid memories of that remarkable trip, and those of the year before, were recounted in Chapter 11 . In the summers in the 1950s the Schwingers typically drove across the country. They would begin by going to New York to visit Julian’s parents, to West Virginia to visit one of Clarice’s brothers, and to Cincinnati to visit her other brother. Then they would head off to the West Coast. In 1956, for example, they spent the summer at Stanford, and in 1957 to a meeting in Banff, which we described earlier as well. * Seattle was the destination one summer; and Madison, where Clarice felt rather isolated, was the base in 1958. † Stanford, again, was home in the summer of 1961, where they had a horse ranch in Woodside, as recounted in Chapter 11 . Several times UCLA was the destination, starting in 1947; we recall from Chapter 14 that Julian always liked Los Angeles, while Clarice did not. Of course, Clarice’s mother Sadie lived with them, but Julian’s parents came to visit twice a year. Julian’s father Benjamin died in 1953, although, revealingly, Julian could not recall the date in 1988. While Julian’s father was alive, when (p. 579 ) his parents visited they stayed at a hotel. When he died, Julian’s mother Belle would stay with them. 9 Generally travel was work-related for Julian. ‘I am rather hazy about the traveling in , but for the trips, the two trips that were taken to Brookhaven in the summer, because these were important stages for me, not of tourism but of sitting down and working, developing these new concepts. That was 1949 and 1950 in the summer,’ 4 when he was working on the new theory of quantized fields based on the action principle. The highlight of their travels was the trip to Yucatan in 1962, where they spent time visiting the Mayan ruins. This reflected Julian’s interest in archaeology—he collected artifacts and read avidly on the subject. 10 This excursion was unique because this was a pure pleasure trip. Nearly all of Julian’s travels were associated with a meeting or a professional invitation, but this trip, and a later one in the 1980s with the Puttermans to Guatemala, was one of their few pure vacations. 1962 also brought a trip to Leningrad. Julian was an exchange professor for three weeks. He had a good time, but Clarice had a very good time. When people entertained them at dinner and learned that her mother came from Russia they were delighted. Clarice recalled visiting somebody who served the most marvelous cherry conserve. It was so delicious, just like her grandmother used to make, that they sent her home with a jar of it and a Russian cookbook. 9 Julian had other recollections: ‘We were staying at the Hotel Astoria with the St Isaac’s Cathedral next to it. The university was on the other side of the river. Somebody would pick me up in the morning and I would deliver lectures, walk back, and all the students would come with me, using the excuse to ask questions on goodness knows what.’ 4 After Russia, they had to return home briefly, for Julian to receive an honorary degree from Harvard. Then they returned to Europe, first visiting Trieste, followed by Yugoslavia, and then they traveled to Geneva, for the High Energy Conference. (For more on that summer, see Chapter 11 .) Their 1963 sabbatical in Paris was memorable; they had an apartment in the 16th Arrondissement while Julian worked at Bures-sur-Yvette. Brief side excursions that year were to Israel and to Greece. That was also the year Julian bought his first Italian car, a Flavia Lancia , nicknamed Brigitte Bardot We have also recounted that year’s adventures in Chapter 11 . And of course they would never forget their trip to Stockholm in 1965. The saga of the Nobel Prize has also been recounted in detail. As an outcome of the Prize, Julian bought Clarice her Volvo . Earlier that year, Schwinger had replaced his Lancia with another blue Italian sports car, an Iso Revolta , bought on the assumption that its Corvette engine would make servicing in America easier. Even though the Lancia was only two years old, Julian had fallen in love with the Iso at a New York automobile show and ordered it on the spot. (For a description of the specifications of that (p. 580 ) remarkable automobile, see the recollection of Lowell Brown * in Ref. 18.) They visited Rome again in 1968, after which they went on to Florence, Duino, and Yugoslavia again. The key point of that summer was four weeks in Trieste, † where they stayed at Prince Raimondo’s Duino Castle as described in Chapter 13 . ‡ After Trieste, they went to Lindau for their first attendance at the annual meeting of Nobel laureates, and then to Geneva. Julian very rarely traveled without Clarice. One of the few times was in 1964 when he went to Dubna, followed by a short visit to Copenhagen. That, and Julian’s solo trip in 1961 to the Solvay Conference in Brussels, are described in Chapter 11 . The Schwingers’ favorite sabbatical was the six months they spent in Tokyo in 1970, with support from the Guggenheim Foundation. § Schwinger spent most of his time writing his treatise on source theory, Particles, sources, and fields , and in the preface to the second volume of that series expressed regret at the time devoted to writing: ‘Some day, when not preoccupied with the writing of a book, I shall return to Japan and fully savor its delights.’ 19 (p. 581 ) Clarice felt that Kazuhiko Nishijima * was responsible for their happiest sabbatical. 21 (Clarice’s perspective on this trip was the subject of pp. 467-469.) However, Nishijima recalled it differently. 20 ‘In 1969 I received a letter from Julian informing me of his plan to spend his sabbatical in Tokyo. This was, however, the only letter from him to me. After that I tried to contact him in order to make necessary arrangements for their stay, but he did everything by himself. Indeed, he had been very well prepared. Before coming to Japan he studied Japanese and could even read and write fairly many Chinese characters. Also he negotiated a Japanese physicist from Tokyo for renting his house during his absence from home. ‘In January 1970, Julian and Clarice flew to Japan and after spending some time in a hotel they moved to the promised house. Soon after that I invited them to our home with some physicists including Tomonaga and his wife. Although Tomonaga, Schwinger, and Feynman shared the Nobel Prize for Physics in 1965, Tomonaga did not attend the ceremony in Stockholm because of an accident at home and it was practically the first time for them to meet.’ Once they arrived in Japan, Nishijima did everything to make sure that the Schwingers had a good time. ‘One of the highlights of their stay in Japan came in early April. In that year the annual meeting of the Physical Society of Japan was held in Kochi, Shikoku. Shikoku is the smallest of Japan’s four main islands and is the site of the famous eighty-eight temple circuit in honor of the great Buddhist saint Kukai or Kobodaishi. Julian was going to give an invited talk on dyons at this meeting. ‘I was to accompany them on this trip and we took Shinkansen (super express) from Tokyo to Osaka and then local trains to Uno, a port town. We took a ferry boat from Uno to Takamatsu to cross the Inland Sea. Takamatsu is a city on the northern coast of Shikoku. It was already evening when we arrived there. We stayed overnight in this city. Next morning we visited famous Ritsurin Park in this city and then set off for Kochi by a local train. During the train trips in Shikoku I had to feed them with “bento,” a modest box lunch, since nothing else was available. I guess it was not to their taste, but they pretended to like it for some time. ‘In Kochi he gave a lecture on dyons and his picture appeared in a local newspaper that evening. Here he experienced something characteristic of Shikoku, namely, he tasted raw whale meat. When the meeting was over we visited tourist spots along the southern coast of Shikoku by bus or taxi, and Julian was impressed by the fact that the famous name Kobodaishi is scattered everywhere in Shikoku. One scenic place was called “Minokoshi,” meaning “left unseen.” (p. 582 ) ‘Julian: “Left unseen? By whom?” ‘I: “By Kobodaishi.” ‘Julian: “Oh, here he is again!” ‘On the way back we finally arrived at Kobe, a modern port city, after crossing the Inland Sea. Julian was eager to enter a restaurant to order beef steak since Kobe is famous for her beef. He was finally released from bento in Shikoku. ‘In the summer of that year the World Exposition was held in Osaka and there were many foreign visitors to this Expo. One of them was Professor Bogoliubov who was on his way to the Expo as a representative of the Soviet Union. He gave a lecture at the University of Tokyo and then we invited Professor and Mrs Bogoliubov for a dinner. Julian and Clarice met them there, but I do not recall what they talked about that summer. ‘The Expo site was extremely crowded and in order to visit a popular pavilion visitors had to wait many hours in a long line. Julian knew someone in charge of the American pavilion, and thanks to his introduction to this person I could visit the American pavilion without waiting. ‘In general Julian was fond of Japanese dishes. Shortly before his departure from Japan I took Julian and Clarice to a famous tonkatsu restaurant. Tonkatsu is a sort of pork cutlet, but the way it is prepared is characteristically Japanese and the sauce used for tonkatsu is also unique. Nowadays soybean sauce is found everywhere in the world, but tonkatsu sauce is found probably only in Japan. Anyway he liked tonkatsu so much that he blamed me on the spot: “Why didn’t you take me here earlier so that I could come here more often before I leave?” ’ 20 The Schwingers continued their nearly yearly travels to Europe after they moved to Los Angeles in 1971. For example, in September 1972, Schwinger attended the international symposium on The Physicist’s Conception of Nature , held at the International Center for Theoretical Physics, Trieste, which was organized by Jagdish Mehra to celebrate P. A. M. Dirac’s 70th birthday. Mehra invited Schwinger to give a talk about his own work on quantum electrodynamics from an autobiographical point of view. However, Schwinger gave ‘A report on quantum electrodynamics’ . (We described part of this report in Chapter 13 .) When, in May 1980, at the Fermilab symposium on The Birth of Particle Physics , Schwinger gave his lecture on ‘Quantum electrodynamics: an individual view’ , Mehra remonstrated with him that this was exactly the kind of talk he had invited him to give at the Dirac Symposium in 1972, and Schwinger replied: ‘I felt too shy then to talk about my own contributions in front of Dirac!’ The old university in Tübingen was a frequent destination, because of the Schwingers’ friendship with the Dittrichs. For example, they spent the summer term there in 1981, thanks to a Humboldt Prize, as described in Chapter 15 . (p. 583 ) But after the mid-1970s, Schwinger stopped attending the big conferences, particularly the International Conferences on High Energy Physics, the ‘Rochester Conferences,’ which through the 1960s he had participated in regularly. In 1982, for example, that meeting was held in Paris; the Schwingers were there, but Julian did not participate in that meeting, but rather the International Colloquium on the History of Particle Physics which immediately followed the big meeting, 21–23 July, 22 at which he repeated the historical talk he had given at Fermilab two years earlier . Milton recalled encountering Julian and Clarice at a concert at Sainte Chapelle. The Schwingers invited the Miltons to tea at their rather modest hotel near the Eiffel Tower. The Schwingers came to Erice in Sicily, to attend the International School of Subnuclear Physics in 1986 and 1988. In the latter year Schwinger gave his talk on ‘Anomalies in quantum field theory’ , and was presented with a birthday cake to honor his 70th birthday. 23 , 24 We alluded to the adventure in Guatemala about 1980, a trip Julian and Clarice took with Seth and Karen Putterman and their two-year-old daughter Rita, ‘who never complained.’ On that trip, because of heavy rains, planes were not flying out of Guatemala City. The Schwingers rented a jeep, which they discovered had no brakes, and drove from Guatemala City to Flores and thence to Tikal. They stayed at a hotel near the Tikal ruins, where the man sent out to get provisions never returned; the first night they had chicken, the next skin and bones. On the return drive, they got stuck and had to be towed. It was not easy to get the jeep on a ferry boat, where they had to supply their own rope. In short, it was quite a remarkable adventure, but one well-worth enduring in view of Julian’s love of pre-Columbian art and archaeology. North American Indian art was also fascinating to Julian, and of course on a number of occasions they visited Chaco Canyon, Canyon de Chelly, Mesa Verde, and other sites in the Southwestern United States. 10 A gourmet and his vineyard In Schwinger’s bachelor days, he was strictly a steak and chocolate ice cream man. Clarice explained that it was just so easy for him not to think of what it was he was going to eat when he was by himself at a restaurant. He would just sit down and give his usual order, continue thinking what he wanted to think about and go away. He continued with this diet even after their marriage, although he encouraged Clarice to be more adventuresome. 9 A variation was provided once a year. They always spent New Year’s Eve with Clarice’s friend Rhody Abrams where they would have boiled lobster and champagne and Burgams’ chocolate ice cream. She would provide a detergent bucket and the Schwingers would come with the lobsters; sometimes they would (p. 584 ) have clams first, but always there were lobsters. They continued this ritual for many years. 9 But Julian’s tastes were transformed by the summer in Europe in 1949. Visiting Europe was always an excuse for gastronomical adventures. For example, in 1957 Julian participated in a mathematical meeting in Lille, which we described in Chapter 11 . He especially remembered an extraordinary dining experience at a tiny restaurant, La Pyramide, which he visited again in 1961 when he attended the Solvay Conference in Brussels. 4 Jane Wilson recalled that she and Robert Wilson were close to Clarice and Julian in the fall of 1946 when they were not yet married. Julie was the youngest tenured professor at Harvard (I think), and Robert possibly the next youngest. The rest of the physics department seemed old and settled. We had a good time together—mostly eating in fashionable restaurants. We also went to the theater. ‘After Robert left Cambridge we saw them frequently at conferences and we usually had dinner together. They visited us once in our Ithaca house. ‘When I think of Julie I think of fancy cars, fancy food—Lobster Savannah in Boston or munching our way through the Grand Vefour in Paris—an excellent menu.’ 25 Clarice recalled an early dinner outing with Harvard faculty, where the Kembles took them and another couple out to dinner. They took them to a very nice restaurant on Charles Street in Boston. The other women talked about schools and children. Clarice had been married six months and there she was in a car with two women who were just talking about schools and children. Her life was simply not attuned to that. She found the evening very pleasant, but she felt that she just wasn’t part of that life. 9 The Schwingers did not have casual social interactions with their friends. During the Army–McCarthy hearings, the Van Vlecks, who lived across the street from their house on Fayerweather Street in Cambridge, would come over to watch, because they did not have a television set. They would come over after breakfast and watch television together and then they would go home. It was not much of a casual dropping in, because one did not drop into the Schwingers’ house. They did not have that kind of easy interchange. But it was different with Victor Weisskopf. He came to Julian and Julian responded. They would go to lunch once a week; this was Vicki’s doing. Julian would never have initiated such a thing, but he enjoyed doing it until a crowd started to tag along, at which point he discontinued the luncheons as we described in Chapter 5 . On the other hand, the Schwingers went out with the Felds, to dinner and the movies or the theater. A February ritual did develop early, because Julian’s birthday was the 12th, Ellen Weisskopf’s was the 10th, and Herman Feshbach’s was the 2nd. And the Schwingers could not imagine having a dinner party without inviting the Felds; (p. 585 ) so every year Clarice would have a dinner party for Julian’s birthday, which became a memorable tradition. 9 The first year the Schwingers became very fond of Percy and Olive Bridgman. They were still living in Boston with Clarice’s mother. That winter was a grueling one, with snow literally waist high. Mrs Bridgman came on the streetcar to have tea with Clarice and her mother. Clarice regarded that as an extraordinary thing to do, because it was a long hard subway ride and a long walk. She wore the fur coat, which Percy Bridgman had bought from his Nobel Prize money. He apparently had a sweet tooth because she took half the cake that Clarice’s mother baked home to him. 9 The wife of the President of Harvard, James Conant, also came to call, while Clarice and Sadie were in the middle of house-cleaning; she dropped in with her white gloves and her card. 9 A very special friend was Ed Purcell. He was a very dear man and a wonderful teacher. Clarice always thought of the Purcells’ children when people talked about bright children or bright parents, because the boys were so sweet, bright, and as enterprising as they could be. Clarice was appalled by a teacher’s saying, ‘I would expect better of a Nobel Prize winner’s son’ in front of the whole class at school when one of them made some sort of mistake. 9 Recall that it was Ed Pur-cell’s coming to Harvard after the war that convinced Schwinger that he should choose Harvard too. ‘There was mutual admiration between Ed and Julian.’ In fact, although Ed was an experimentalist and Julian a theorist, there was much in common between the two men. Both owed their careers to Lark–Horowitz, the chairman of the Physics Department at Purdue in the 1930s. Lark–Horowitz gave Schwinger his first real position, and somewhat earlier he had introduced Purcell to physics: ‘Ed hadn’t known what physics was until Lark–Horowitz had him work on this experiment.’ 26 For several years after they both arrived at Harvard, the Purcells and the Schwingers would get together for dinner once a month. Beth Purcell recalled that ‘Julian was not reclusive, he liked to be with people, but he had a certain reserve. When he was with people he knew and liked he was quite outgoing. He was not the life of the party, but he participated in social occasions. He was not gregarious or outgoing, but he enjoyed a good conversation with good friends. Julian had a wry sense of humor. One had the feeling that he was aware of his own ability, and didn’t underestimate it.’ 26 Things went on much the same way after the Nobel Prize. In Belmont they lived quite nearby to the Desers, the Malenkas, and the Martins and they saw them often. Because they all lived in Belmont, there was an easier interchange of visiting back and forth. Their social life consisted of visiting with Clarice’s old friends, people at MIT, and the family. Nothing really changed in that respect. 9 In 1967 the Malenkas and the Martins gave the Schwingers a surprise twentieth anniversary party; Clarice was not happy about it. 9 More successful had been a couple of earlier costume parties that the Malenkas hosted, which many of (p. 586 ) Julian’s students and colleagues attended. For one of these parties, Julian came dressed as a dashing musketeer. 27 They lived within walking distance of their friends in Belmont. Clarice found it was pleasant living there. They had a nice house with beautiful trees and a pretty garden and were off the main traffic line; yet it was only a ten-minute walk to the bus. And marketing was nearby. When she first got her Volvo , she disliked driving so much that she would walk down to market, leave the groceries at the market, come back and get her car and drive to pick them up because she could not carry them home. But the idea of driving to market did not seem pleasant to her. 9 When friends moved away, the Schwingers maintained the friendship, but without much contact. For example, Madlyn and Mort Hamermesh left Cambridge after the war, but when the Schwingers, a few years later, spent a summer at Brookhaven, the two couples became rather close again. Clarice felt that they had always been close and warm, and whenever they got together they immediately took up from where they had left off. But the Schwingers did not write or call. It was just a longstanding friendship. And this was true of most of Julian’s friends who went away; they maintained relationships but not contact. 9 The Kivelsons were among the Schwingers’ closest friends in California. They often had dinner together. Margaret Kivelson recalled Clarice’s kindness in allowing shop talk: ‘Particularly when we’d come to dinner at their house, Julian would always want to know what was going on with my space craft, what we were discovering. He was very interested. I always looked forward to telling him what was new. Clarice was always happy to see him involved. She has an amazing talent. I rarely talk science in social situations when there’s somebody there who’s not a scientist, but Clarice had a way of making you feel it’s quite all right, she’s interested too. That’s the thing I would say was most exceptional. She always encouraged this part of the interaction, never making it seem we were boring her to tears.’ 28 A special event occurred early in their life in Los Angeles. On 3 October 1973, Jagdish Mehra, at the request of Yuval Ne’eman—then President of Tel Aviv University—organized a symposium on ‘The Present and Future Goals of Science,’ which was held at the Century Plaza Hotel in Los Angeles to celebrate the Decennial Assembly of Tel Aviv University. Los Angeles was the headquarters of The American Friends of Tel Aviv University and the home of Victor Carter, Chairman of the Board of Governors of the University. Among the speakers and attendees were Willis E. Lamb, Jr, Sir John Eccles, Robert Sinsheimer, Allan Sandage, Edwin McMillan, Owen Chamberlain, Murray Gell-Mann, Emilio Segrè, Alfred Kastler, Leon N. Cooper, and Julian Schwinger, whom Mehra had invited to be Chairman of the Symposium. Schwinger served as a most efficient (p. 587 ) and gracious Chairman who kept everything moving on a tight schedule, and the Symposium was a huge success. That evening, after the Symposium, there was a dinner–reception at the house of Mr Carter, and many wealthy persons were invited to pledge support for the advancement of education and research at Tel Aviv University. The Yom Kippur War against Israel had just been declared, and Edward Teller gave a rousing speech to all the assembled invitees and prospective donors. The pledges had been intended to be made for Tel Aviv University but, by general consent, the monies pledged that evening—millions of dollars—were made a gift to the State of Israel for its war effort. The initial plan was that the distinguished Nobel laureates would all travel to Israel as guests of Tel Aviv University and be received by the Israeli President, but this plan had to be dropped in view of the war. On the eve of the Symposium, Julian Schwinger had made a reservation for dinner for himself and Clarice and Jagdish and Marlis Mehra at the Japanese restaurant in the Century Plaza Hotel, while—without knowing about that—Mehra had made a reservation for the four of them in the French restaurant across the hall. Mehra, who did not fully appreciate the subtleties of Japanese food, had to use great diplomacy to steer Julian and Clarice into the French restaurant as his guests. There, Julian ordered filet mignon with a spread of mango chutney, and everyone joined him. It was a most unusual and exotic dish, and Julian was very pleased with his selection, as was everyone else. It went very well with a bottle of Chateau Laffite-Rothschild 1957, and the whole event became memorable. The V. Sattui Winery A major event in Schwinger’s life occurred in 1975. He learned that the scion of an old winemaking family in California, the Sattuis, was attempting to revive the family business. Vittorio Sattui started making wine in the 1880s and became quite successful. But Prohibition came in 1920, and destroyed the business. His great grandson Darryl Sattui finally began to realize his lifelong dream to restart the winery in the mid-1970s. ‘I approached famous movie directors, lawyers, renowned surgeons, a Nobel Prize winner, my friends, anyone who had a little money and might be interested.’ 29 He finally managed to raise a bit over $50 000, started the business on a shoestring, and actually turned a small profit the first year. For several years the operation barely survived, but it succeeded by selling only directly to the consumers. This success was achieved with no compromise in quality: ‘In 1997 V. Sattui Winery won an astounding 47 Gold Medals in major international and domestic competitive tastings against the world’s best.’ 29 Julian was the Nobel Laureate referred to above. He learned of the project while touring a winery where Sattui was working as a guide. 30 In a recent letter (p. 588 ) Sattui has described in detail his relationship with the Schwingers. ‘Prior to re-establishing the winery in 1975 I courted Julian Schwinger among others to get him to invest in my project. After a series of letters between Julian and me, he invited me to his home near UCLA. During the conversation Julian offered me a glass of white wine and a moment later asked me what I thought of it and more specifically what it was. I remember answering chardonnay, and he replied, “No, it’s not chardonnay, it’s French colombard.” I realized then that he had tested my knowledge of wine, and on that specific test I had failed. For surely Julian was trying to ascertain my level of knowledge about wine prior to making the decision to invest or not. * ‘Well, Julian did invest in my new winery, V. Sattui. And I would like to think it was the best investment he ever made even if I couldn’t tell the difference between chardonnay and French colombard when I was first starting out. ‘Each year the stockholders of V. Sattui Winery, of which Julian was the second largest (with more than 12% of the stock), met for a stockholder’s meeting. And always the night before I would have dinner with Julian and Clarice. About eight years ago (fifteen years after Julian invested) at one of these dinners I happened to thank Julian and Clarice for having enough confidence in me in the beginning to take a chance on me. By this time we were quite successful, but without Julian and Clarice believing in me from the beginning the winery might never have gotten started again. ‘Before Julian could reply Clarice retorted, “Don’t thank me, I never wanted to invest in the winery. Thank Julian. It was totally his idea.” ’ She went on to say that she had been totally against it, and was angry and hurt over the idea, and was very upset after he essentially invested their meager life savings into (p. 589 ) the rebirth of my winery. She added, ‘But Julian had a feeling about you and knew you would be successful, and he persisted despite my grave doubts.’ She later said that Julian had an instinct about people and their potential and that he was almost always right. ‘Julian was a very modest man. For years I never knew who the second biggest stockholder was. He would come to meetings and listen to me the whole afternoon. Occasionally he would have something to say, and it would never be something frivolous. When he did speak at our meetings, always in that soft-spoken modest way of his, it was always pertinent to real issues. But most of all he listened, never saying a word. I often wondered what he really thought. ‘When Julian first invested (again I say Julian because Clarice wanted no part of V. Sattui Winery), he had to fill out a questionnaire for the Bureau of Alcohol, Tobacco, and Firearms. For this government agency wanted to be sure unsavory types or criminals were not allowed in the wine business. It must have been a legacy of Prohibition. I remember getting Julian’s form back, and it didn’t seem unusual to me. He listed himself as a university professor and answered the question about where he got the money to invest by answering “from books.” I just assumed that he was one of many professors that were compelled to publish in order not to lose their jobs. ‘About eighteen years after Julian had invested with me thinking he was just another university professor, the President of the entire nine-campus University of California system came into our tasting room (I believe his name was Hey-man * ) one day. He happened during our conversation to ask if I knew who Julian was, I said, “Sure I do. He is a professor of physics at UCLA.” He laughed and replied, “So you really don’t know who Julian is. That man is so modest!” Then President Heyman went on for five minutes regarding Julian’s accomplishments, the Nobel Prize, the National Medal of Science, etc., etc. I was dumbfounded. For all these years I had had this relationship with one of the great men of the twentieth century without so much as an inkling. ‘In many ways Julian and I had about as much in common as rain and sunshine. He was the physics legend, and I could hardly spell physics . The only physics course I took in college was a watered down one for business students. I couldn’t even understand much of his book written for the lay person trying to explain Einstein’s theory of relativity . In fact I could only read 48 pages and comprehended almost nothing. He was disappointed that I understood so little, as he was trying to reach the average guy to foster more interest and understanding in physics. It didn’t happen with me. ‘Julian and I were from two different worlds. Most of our interests were worlds apart. Yet we got along well. We never argued in nearly twenty years. He always (p. 590 ) backed how I ran the winery, even when others didn’t. And he always voted the way I hoped for at meetings, and he never meddled in the daily running of the business or the minute details. But he and his wife Clarice never failed to come from Los Angeles for our annual meetings. ‘I’m sure that Julian was a lot of things to different people. I didn’t see his physics side, and I regret I never attended one of his lectures which were apparently marvelous. But I found all this out too late. ‘The Julian I did know was a kind, humble, gentle humanitarian with a dry sense of humor, who didn’t say much. But perhaps some of the physicists didn’t realize that Julian appreciated a good glass of wine, going out, good food, traveling, tennis. He had a zest for life. And he had his own fantasies such as owning part of a winery. ‘The fact that two people so incongruous as Julian and I ever even met and had a nearly twenty year relationship never ceases to make me think how absolutely fascinating and unpredictable life really is. I know I am better off for having had the opportunity to have known and spent time with such a great man (and not just great in the sense of physics but as a fine human being), and I truly miss him.’ 31 , * The teacher and his disciples From his first day at Harvard, Schwinger always had one or more ‘assistants,’ what we would now call ‘postdocs.’ The first was Harold Levine, one of his close collaborators at the Radiation Lab. ‘I took him with me to Harvard as sort of my assistant. I guess I was granted the privilege. He took notes of these lectures and he had an absolutely beautiful hand and the notes were very widely circulated because I think at the time it was the one up-to-date text on the then situation in nuclear physics. I think there was some competition, later, from Serber, in a famous set of notes “Serber says.” I guess I am more famous for what I have not published than for what I have.’ 4 Immediately Schwinger acquired a host of talented PhD students. In spite of the fact some of them felt that Schwinger didn’t care about them, in fact he recognized that their presence was essential. ‘In 1948 and 19491 put out at least 10 or 12 PhDs . I had to come up with problems for all these people, which was part of the stimulation.’ Unlike Feynman, Schwinger (p. 591 ) always had an ongoing program, and any number of problems that he, himself, did not have time to pursue. He was, in fact, very kind to his students, never turned anyone away who wanted to work with him, and ultimately graduated 73 PhDs, many of whom became distinguished leaders in physics and other fields, including three Nobel Laureates: Sheldon Glashow, Walter Kohn, and Ben Mottleson. Schwinger ‘was hard to catch, but when I was caught I gave them the attention they needed to go to the next step and no more.’ 4 Schwinger avoided the administrative duties that take up so much of the time of an ordinary professor. His one committee assignment was very revealing, if ineffective. ‘I can only think of one committee I was on, which had to do with whether we should get involved in developing computers. This must back in 1948. Van Vleck was on that committee and I remember them turning to me, and I said, if I really wanted to, I’m sure I could keep that machine busy totally, 24 hours a day, with the problems I could dream up. I was thinking of all the quantum scattering problems one could do. * And Van Vleck’s jaw sort of dropped when I said that and he later said that statement made a very deep impression on him. I think very soon thereafter they reorganized the committee and I wasn’t on it anymore. I was opposed to committees.’ 4 Without Schwinger’s input, Harvard made a fateful, wrong, decision not to establish a computer lab, an error not rectified until the 1960s. Robert Raphael, who received his PhD in 1957 under Schwinger’s direction and went on to become a Trappist monk, offered a succinct summary of what he had gained from Schwinger: ‘Close attention to phenomena coupled with a drive towards unification using powerful analytical instruments capable of revealing their inner structure—this lesson I learned at the master’s feet, and it has stood me in good stead.’ 32 Schwinger’s lectures, delivered around the noon hour, were the beginning of his day at Harvard. Invariably these took place on Monday, Wednesday, and Friday; Tuesday and Thursday Schwinger stayed at home. They were marvels of content and presentation, and interruptions were seldom tolerated. But not all of Schwinger’s students were respectful. Larry Horwitz, who was Schwinger’s student in the mid 1950s, wrote that ‘I was among a group of, I think, nine students that he took simultaneously, including Glashow, Johnson, Baker, Sawyer, Sommerfield, and Garrido. I wrote down everything that Schwinger said, but sometimes Glashow read a newspaper during class, and actually asked Julian questions!’ 33 Charles Zemach, who started attending Schwinger’s lectures as an undergraduate around 1950, remarked that ‘elegance and analytic power (p. 592 ) were general trademarks’ of his lectures. ‘He was a scientific poet,’ in that he was interested in an esthetically pleasing presentation. Zemach recalled that he typically arrived 15–20 minutes late for his 11:00 lecture, driving up at the last minute in his sleek blue automobile; * of course he never tolerated, and his well-trained audience never asked, questions. Once Zemach brought an untutored friend to listen; he had the audacity to point out one of Schwinger’s rare errors on the board! ‘Schwinger turned around and said, “Sir?” The guy pointed out there was a slight numerical slip there, so Schwinger corrected it. That was totally unprecedented.’ 11 Robert Warnock, who arrived at Harvard in 1953, recalled that the atmosphere of the lectures was ‘rather formal’ in that ‘questions were not tolerated.’ Once a questioner grew more and more persistent, which drew no response from Schwinger except for him ‘getting quieter and quieter and looking down at his feet,’ until the questioner gave up in embarrassment. Schwinger’s lecturing style seemed almost ‘automatic’ to Warnock—once a French television crew came to film one of Schwinger’s lectures, so the students served as extras. Of course, as with all filming, there were pauses; after each pause Schwinger would pick up from exactly where he left off in his lecture. 35 Abe Klein recalled that while he was Julian’s assistant he attended a long mathematical lecture in 1951 on quantum mechanics. The answer emerged as ‘the well-known Gegenbauer polynomials.’ The class laughed at Schwinger’s phrase. A short while later while en route to the annual departmental picnic, the graduate students encountered signs reading ‘this way to the well-known Gegenbauer polynomials.’ 36 Klein also remarked that Schwinger’s lectures were not hard to follow, because he repeated everything three times, in different words. 36 ‘On the other hand, he did tend to smooth over difficulties, and it was clear that he didn’t encourage questions, so none were ever asked, at least during his classroom lectures.’ 37 One of Schwinger’s less-than-satisfied students was Bryce DeWitt. He arrived at Harvard in January 1946 still wearing his Navy uniform, the same term that Schwinger started teaching there. DeWitt recalled the first course was on the electromagnetic theory of light, where, as always, everything came out of Schwinger’s head. Once, when he forgot a cross-section, Schwinger consulted a piece of paper which he brought out of his pocket, at which point everyone booed! Schwinger clearly wasn’t used to students, and the final exam was a disaster. ‘When the bluebooks were passed around, we all just sat in stunned silence for about half an hour, without raising a pencil.’ Among other things he asked the students to reproduce the 1938 classical radiating electron theory (p. 593 ) of Dirac, 38 something he had not touched upon, but which he felt should be regarded as a ‘corollary’ to what the students had learned. Schwinger gave everyone a B; years later DeWitt happened to be in Schwinger’s office alone, saw a stack of blue books, pulled them down, and discovered they were those old examination papers, ungraded! * For a later course on quantum electrodynamics DeWitt took careful notes. ‘At 11:20 a door in the back of the room would open, a stooped figure with a shock of black hair would poke his way around the corner, and there he would be. He would pick up the chalk, and would always say, “At the end of the last hour,” and then he would just start writing,’ picking up right from where he had left off the last time. Afterwards, DeWitt would recopy his notes and fill in the details. ‘Every so often, I would throw down my pencil, saying, “That son of a bitch has done it again!” ’ when he discovered a ‘big gap in the logic.’ 40 This was hardly the universal view, however. Richard Arnowitt found his ‘lectures superb. I never felt they were facile, or left out the hard parts, as some others have felt. Julian was one of the great teachers of our time.’ 41 Lowell Brown also spoke of Schwinger’s marvelous lectures, the details of which, if not the broad strokes, found their way into his own book on quantum electrodynamics. 42 But he recognized that the downside of Schwinger’s presentation was that he did not put the subject into context or provide the historical background. 43 Schwinger’s lectures were hermetic—their self-contained nature was both their strength and their weakness. Not only Harvard students (and faculty) attended these brilliant lectures, but faculty and students from MIT came as well. One of the latter was David Jackson. ‘I was a graduate student at MIT from 1946 to 1949. We used to come up occasionally to listen to Julian lecture, always in the afternoon. The impression was one of inexorability. However unique his approach to a topic was, he made the development seem absolutely compelling, with no possible deviations or alternative allowed. His style was very polished, without hesitation or error.’ 17 Walter Kohn painted a magnificent picture of Schwinger’s lectures: ‘Attending one of his formal lectures was comparable to hearing a new major concert by a very great composer, flawlessly performed by the composer himself. For example, his historic graduate courses on nuclear physics and on waveguides given in the late 1940s consisted largely of exciting original material. Furthermore, (p. 594 ) both old and new material were treated from fresh points of view and organized in magnificent overall structures. The delivery was magisterial, even, carefully worded, irresistible like a mighty river. He commanded the attention of his audience entirely by the content and form of his material, and by his personal mastery of it, without a touch of dramatization. Interaction with the audience was as rare as in a formal concert. Crowds of students and more senior people from both Harvard and MIT attended and, knowing his nocturnal working habits, I found the price of having to wait 10, 20, 30 minutes for his arrival quite trivial in comparison to what he gave us. I felt privileged—and not a little daunted—to witness physics being made by one of its greatest masters. Each of these two courses had a tremendous influence on the shape of their respective fields for decades to come, as did other later Schwinger courses such as quantum mechanics and field theory.’ 44 At Harvard, a ritual developed which continued for many years. Every Wednesday afternoon (and in earlier times, Fridays also—Mondays were occupied with faculty meetings), after Julian would return from lunch, perhaps at 3:00, students would file in to see the master sometimes according to a list which they had signed earlier in the day. As he had typically more than ten research students at a time, if one’s place in the queue were unfavorable, one might not get in to see him that week. Even Schwinger’s long-time assistant was not given higher rights. Horwitz made this point: ‘One day, waiting in line one Friday afternoon, I met Harold Levine, his close collaborator on many works. I asked Harold what he was doing there, and he said he was waiting in line like everybody else.’ 33 Alternatively, a higher-ranking individual might displace all the students. In the 1950s that might be Pauli, 33 or Weisskopf and Feshbach, or his assistant Kenneth Johnson. 45 In the 1960s such a person was Bruno Zumino, who was visiting Harvard on sabbatical. Zumino, and perhaps David Boulware, then Julian’s assistant, would go out for lunch together with Julian and sometimes never return. Michael Lieber remarked, ‘I remember one afternoon when it had been drizzling, and Julian had gone for lunch with, perhaps, Zumino. We sat in the outer office waiting for him to come back, sure he would return because his coat was hanging on the coat hanger. But he never came back that afternoon.’ 46 , * (p. 595 ) A more dramatic story is told by more than one of his students. Norman Horing recalled entering Lyman Hall to to see a line of Schwinger students waiting outside the bathroom. Apparently he had entered, and the students were afraid that if they did not catch him there he would slip away home. After a while, someone checked the bathroom, and indeed one of the stalls was occupied. But when the occupant emerged, it was Robert Puff, another graduate student. Either Schwinger had slipped out of the bathroom before the students gathered, or he escaped by the window; but in any case he was not seen again that day. 47 , 48 As a result, students typically would see Schwinger infrequently. Richard Arnowitt recalled that he saw him maybe once a month, but that was because ‘I would do everything I possibly could until I was completely stuck.’ When he did see Schwinger, ‘he’d think for a few seconds then rattle off five things that I’d never thought of. For me it was one of the great learning experiences.’ 41 How students reacted to Schwinger’s mentoring technique depended in large measure on what they were seeking. ‘Julian was hard to work with if you wanted guidance, but easy to work with if you wanted inspiration.’ 41 Or as Roger Newton put it, as a ‘thesis supervisor he was extremely helpful when you needed help. But those who wanted a lot of interaction were in extreme difficulty.’ 49 Abe Klein remarked that he had only the best feelings about Schwinger even though he may have seen him only six times while working on his thesis. 36 In his published recollections, Klein remarked that he had only three decisive interactions with Schwinger during his eight-and-half years at Harvard. ‘If he thought you needed help, he did his best to provide it. Otherwise, it was laissez faire . ’37 We have also noted the limited, but very successful, interaction of Margaret Kivelson with Schwinger. One of those who needed more guidance was Raphael Aronson. Admittedly, in 1949, he was the youngest in the class, and immature; he was viewed as a child prodigy. He found Schwinger’s lectures disappointing; the ‘big thing’ was missing, ‘everything came out as in a textbook, with no loose ends. Physics is about the loose ends, and I needed that lesson.’ His first two thesis topics were unsuccessful; and even his thesis, on neutron–proton and proton–proton scattering, using the strong coupling theory of Kemmer and others, turned out to be incorrect because it violated isospin symmetry. The result was disillusionment; Aronson was turned off from physics. Yet even he eventually came to see the debt he owed Schwinger; his later work in reactor shielding and transport theory could not have been accomplished without the experience of Schwinger. (p. 596 ) Schwinger’s hallmark, in many ways, was formalism; and the fact is that often one can ‘only see the physics with the formalism.’ 50 , * Schwinger’s lack of availability angered some students. One of those was Walter Kohn. ‘Kohn was miffed by Julian’s unavailability. He completed his thesis, wrote up a paper, and submitted it to Phys. Rev . without ever consulting Julian.’ 17 DeWitt also had less than the usual limited amount of contact with Schwinger. Part of his isolation was self-imposed. While most of the theory students shared a large office in the basement of Jefferson Lab, DeWitt was resident tutor at Kirkland House, and working largely there, did not share in the interactions of Julian’s students and assistants in the physics building. 40 As Eugen Merzbacher noted, ‘DeWitt was very much to himself and had no interaction with Julian.’ 51 (This may have some bearing on his letter to Pauli that caused a crisis which only a personal visit by Schwinger could resolve. See Chapter 8 .) Some of the students who wanted to work for Julian were palmed off on one of his assistants. For example, Schwinger suggested that Roy Glauber give Charles Zemach a problem on neutron diffraction. Zemach found that Schwinger did not welcome students; and that the students had to come up with their own ideas for problems. At various points Zemach tried to get Schwinger interested in his problem, but to no avail. At the end, he explained his results to the master, who remarked that he had done some calculations on a related matter, but then forgot his promise to dig out his old notes. Zemach characterized Schwinger’s relationship to his students as ‘standoffish behavior on his side, absolute adulation on the students’ side. We were willing to get whatever crumbs we could pick up from him. Everyone realized he was something special. He was thought to be the greatest physicist in the world by those of us who sat in his courses.’ 11 But it seems that the majority of Schwinger’s students were satisfied with what they received. Marshall Baker, for instance, may have seen him seven times in the two years, 1955–57, but had no desire to see him more, so much material being given at each meeting. 52 The wait might be interminable, but once admitted into the inner sanctum, time could stop. Schwinger gave the student undivided attention for as long as required. Walter Kohn remarked, ‘Arranging to meet with him was devilishly hard, but when it happened—a few times a year—I found him most generous with his time and brilliant in his judgments and suggestions. It was during these (p. 597 ) meetings, sometimes more than two hours long, that I learned the most from him. He had a large old-fashioned office in the old Jefferson building. In one corner, at a desk, sat Harold Levine calculating away on intricate classical wave problems, totally oblivious to what was going on around him. Drifting in and out were other students anxious to catch Julian. Frequently Herman Feshbach came over from MIT to talk about nuclear forces. A few times Freeman Dyson and Richard Feynman dropped in to talk about quantum electrodynamics. Once a letter or preprint from Tomonaga arrived and Julian said he was nervous to open it, so often had Tomonaga’s thinking been almost the same as his. What great fortune for us to be there at such a time.’ 44 In the mid-1950s these audiences took place in a small room, not Schwinger’s office. One could sometimes catch a glimpse of how Julian’s mind worked; he was not afraid to assimilate the competition. Larry Horwitz wrote: ‘Generally, there were two viewpoints dominating the methods of that time, the functional view of Schwinger, meticulously deductive, based on integral equations and functional derivatives, and the diagram methods of Feynman. One day, in this small office, I asked him a knotty question, and he used a small corner of the little blackboard to sketch some diagrams, quickly erased them, and told me the answer in full functional form.’ 33 In a much later period, Alain Phares was one of Schwinger’s last Harvard students, finishing his thesis after the Schwingers had moved to the West Coast in 1971. In spite of this difficult situation, Phares found his limited interaction with Schwinger extremely valuable. ‘The meetings I had with Julian whenever he was in town were crucial and invaluable. At each of these meetings, which often lasted hours, he made me feel at ease and gave me a lot of confidence in myself. The insight he provided me in every topic discussed was absolutely incredible…. Julian was to me the greatest of all my teachers, humble, considerate, and supportive.’ 53 Robert Warnock, who may have seen Schwinger only four times during his days as a student, summarized the view of many. ‘Being Schwinger’s student was no picnic. He often made appointments but then wouldn’t show up until an hour or two later. He was definitely a mythic figure. However, in his office he was quite agreeable and easy to talk to.’ 35 After abandoning the experimentally ruled out K -meson theory of Schwinger (see below), Warnock was eventually given a problem in multichannel scattering of pions and kaons off nucleons, and worked out a helicity basis for the description of matrix elements, anticipating the work of Jacob and Wick. 54 He concluded that although he first thought his thesis would have benefited from more advice from Schwinger, perhaps he was better off with the little guidance he had. 35 K. T. Mahanthappa noted that Schwinger practiced a self-selective process. ‘He never turned down anyone who wanted to work for him. Students had to find out if it would work out by themselves.’ 55 (p. 598 ) He also recalled it might not be easy to finish. He remembered another student, ‘senior to me by three or four years. He was “tired” of being a graduate student and wanted to get out. As usual with Julian, the student had to bring up the question of finishing and getting out; Julian never said voluntarily, “This is enough for your thesis,” the student had to raise the question. This student brought up the question of writing up his thesis on what he had done so far. Apparently Julian thought that it was not enough. He is said to have told him, “What do you want to do after finishing up? Go and teach in a girls’ high school?” It was very funny to us at that time , especially Julian saying such a thing. Nowadays it would be viewed as a male chauvinistic remark.’ 56 A less offensive version of the same attitude occurred in his remark to Roger Lazarus, who was about to leave academe for a job at Los Alamos: ‘Well, I guess you have to eat.’ 57 Abe Klein seems to have hit the nail squarely on the head in the talk he gave at the Drexel memorial session: ‘Why did we see so little of him once we began work? The stories of how hard it was to get to see him once you decided it was absolutely necessary translate, in practice that sometimes you had to wait up to a week before your turn came. But that does not explain why the average interval between audiences was three months for me, longer for some, shorter for others. My answer, which I believe represents part of the general opinion of his students, is that we were so in awe and had so much respect for the value of his time, as opposed to the value of our own, that we felt it necessary to exhaust all other resources available to us, the literature, our fellow graduate students, and our own efforts, before we went to see Julian. In thinking about those times, I have come to realize that after the short meeting during which I received my first research topic, though I remained in awe of his abilities, I was never again afraid of him, because no matter how poor the quality of the work I had done, he never tried to destroy my ego. I could see that he took my concerns seriously and did his best to come up with useful advice. Only about half the research topics he suggested to me were any good or at least any good for me. Some of his students thought everything should work out perfectly and became and remained angry when it didn’t. I think that those of us who were more realistic in our expectations fared better personally. He also took seriously his basic responsibility to order us according to promise and this explains, but only in part, why bad theses sometimes led to good careers.’ 37 Schwinger rarely complimented his students. Jack Ng was the fortunate recipient of two such compliments. One was described in Ng’s account of his first meeting with Schwinger in Ref. 18, where Schwinger called himself stupid for suggesting inclusion of a parity-violating term. ‘I was so taken aback by his self-deprecatory remark that I thought he must have planned on it (to make me feel at ease). So I checked around to see if the other students had the same experience. Surprisingly, no one else had. I was in seventh heaven for a few days. (p. 599 ) The other time he said that I had the right attitude to be a good physicist. ’58 Clarice emphasized that Julian indeed gave his students as much time as he felt they needed—but not more. She well recognized how much time he spent with his students, as one who often waited until 8 p.m. for Julian to return home. 10 In assessing the degree of effort Schwinger spent on his students, it is appropriate to consider the disparity between his abilities and those of most of his students—even though they all were very bright. Oppenheimer at some time in the 1950s created the unit for physicists, the Schwinger . Students hoped they would be at the level of at least 1 milliSchwinger. 34 Passing the Qualifying Examination was often traumatic for the students, but for reasons of anticipation, not for what occurred during the exam. Schwinger often came to the rescue of the student. Milton recalls that his exam largely consisted of an argument between Schwinger and Martin on the meaning of source theory. On passing, Schwinger presented him with a copy of his recently published Brandeis lectures, Particles and sources . Ng recounted more details of his exam: ‘Glashow asked me a question: why so and so? I could not even understand his question. So I just stood next to the blackboard to ponder on his question. After a minute or so, I was about to give up. Luckily, Schwinger came to my rescue. He just turned his head towards Glashow and said, “Why not?” To my surprise, Glashow replied right away, “OK.” I could understand neither Glashow’s question nor Schwinger’s reply. But to save myself the embarrassment, I kept quiet. I passed the exam.’ 58 Of course, Glashow was understanding, because his thesis defense involved an argument between Schwinger and Yang. 59 Many students have remarked that their thesis topics were often not earth-shaking. * Of course, there were a large number of exceptions, such as Glashow’s work on electroweak unification which we described in Chapter 12 . Again Ng had a story to tell. ‘In one of the gatherings we had at Schwinger’s house, for some reason, we talked about PhD theses. Shortly afterwards, Julian and I were (p. 600 ) alone. I jokingly asked why was I not lucky like Glashow in getting a nice thesis topic. Julian was not amused. He left me alone. Of course, I should have been more diplomatic even in making jokes. But I could tell that he was a little upset with himself for not continuing his work on electroweak unification.’ 58 Julian Schwinger was apprehensive of J. Robert Oppenheimer’s opinion, * but Dirac was the only person whom he held in awe. After the war, when Schwinger settled at Harvard, and Oppenheimer at the Institute for Advanced Study in Princeton, Schwinger began a regular practice of sending his students to Oppenheimer for postdoctoral research. Although he had no interest in going there himself, ‘the impression you got is that everybody was constantly running up and down the hall telling each other brilliant ideas, and going to one seminar after another, and I well recognize for me that would be a total disaster,’ he realized it could be very useful for young physicists. ‘I was very glad to be able to send some of my PhD’s there. That seemed to be the next step in their evolution. For them to get another way of doing things. Somewhere along the line I invented the phrase “conversational physics,” and I can’t remember whether it was pre-war Oppenheimer or referred to what was going on at the Institute, or whatever.’ 4 But the process of placing his students there was not always appreciated. Fritz Rohrlich, one of Schwinger’s first students, getting his PhD in 1949, † recalled that after some of his contemporaries had been offered posts at the Institute, he still had not gotten Schwinger to write Oppenheimer a letter on his behalf. Eventually, Schwinger telephoned Oppenheimer, and Rohrlich obtained the offer. ‡ But he was left with the unpleasant feeling that Schwinger did not care about his students. 62 Most of his graduates, however, appreciated Schwinger’s help. This special relationship with the Institute for Advanced Study continued into the 1960s. York-Peng Edward Yao recalled that when he finished his PhD in 1964, Schwinger wrote Oppenheimer and secured for him a two-year postdoctoral appointment at the Institute. He remarked that Schwinger’s training was good for those who got through the process, but frustrating for (p. 601 ) others. 63 Tung-Mow Yan remarked that Schwinger arranged postdoc offers for him in 1968 at both the Institute for Advanced Study and at the Stanford Linear Accelerator Center; Schwinger was pleased that Yan accepted the latter because it was the site of the ongoing deep inelastic scattering experiments that we described in Chapter 14 . 64 Norman Horing, who also received his PhD in 1964, had a rather typical story to recount. While he was a student of Schwinger’s, he felt that he was not given much attention, and he saw his advisor infrequently. His first thesis topic was based on Schwinger’s ‘Dynamical theory of K -mesons,’ which as we have described in Chapter 12 , was a failed attempt to save parity (space-reflection) symmetry. Horing’s thesis was nearly finished when Daniel Kleitman, another of Schwinger’s students, proved that the scheme was inconsistent with experiment. Horing had to abandon his project, and begin another thesis topic, eventually writing a dissertation on many body physics. Yet this delay did not result in bitterness on Horing’s part; he took it as a learning experience. Later, when the new thesis was nearly finished, Schwinger expressed doubt whether the result could be correct, since it seemed to violate translational invariance. Horing was shattered for a week, and spent day and night rechecking his result. When he encountered Schwinger in the hall the following week, the master admitted that he had been mistaken. But Horing recognized that even though there were these significant ‘misfires,’ he would never have learned proper physics anywhere else. One of his founts of inspiration was a magnificent set of notes taken and edited by Kenneth Johnson of Schwinger’s lectures on quantum field theory. He remains ‘eternally grateful’ for the education he received at Harvard, and recognized that the ‘source is Schwinger, even though it was second hand.’ His personal interaction with Schwinger was ‘nothing much.’ Horing was, at the century’s end, writing a book on quantum many-body theory, which owed much to what he had learned, directly and indirectly, from Schwinger; in his work, for example, the marvelous ‘Gauge invariance and vacuum polarization’ , which we described in Chapter 9 , with its Green’s function techniques, continued to play a decisive role. 47 Horwitz had another view on Schwinger’s defeat by the experiments on parity violation. ‘The results of the parity violation experiments became known on the day of my PhD qualifying examination. Schwinger was apparently thunderstruck; many of his elegant formulations were based on symmetry. Fortunately it did not affect QED very much, but he was surely very quick to see that one of the apparently principal pillars on which the world stood, that of natural symmetry, had become shaky.’ 33 We have noted that certain students felt that their work had been appropriated by Schwinger without due recognition, or their inclusion as co-authors. But this was the exception. Paul Martin noted that, ‘He was the (p. 602 ) loser in that there were many more things he did in unique ways, without being recognized, than he took from others without attribution.’ 15 An example is given by Roy Glauber. In the fall of 1946 Schwinger was teaching nuclear physics, where in understanding the two-body forces between neutrons and protons he invented a variational principle for scattering amplitudes. The question was then, what could you learn about the form of the potential well from experiments at 10 MeV? The answer was very little; only two parameters characterized the interaction—a scattering length and an effective range. John Blatt told the world about this conclusion, through notes replicated at Princeton. Schwinger’s demonstration was not terribly clean, so, with these notes in hand, Hans Bethe found a neat and brief derivation, which he published without thanking Schwinger, only Blatt. Schwinger was very angry. 60 Six months later Bethe would again omit reference to Schwinger in the draft paper of his Lamb shift calculation, as we described in Chapter 7 , even though Schwinger and Weisskopf had discussed the essence of the idea with him at Shelter Island. Schwinger seemed very shy, and seldom became personally involved with his students. This could have a way of making him seem cold and unfeeling. Yet this was not really the case. One of his foreign students recalled that as he was finishing his thesis his mother became gravely ill. Unknown to the student, his father wrote to Schwinger requesting that he allow his son to return home. At the time Schwinger said nothing, but some time later, at the student’s thesis defense, Schwinger asked the student how his mother was. The student was shocked because he had never breathed a word of his mother’s ill health. In the early days at Harvard, probably around 1949, a group of Schwinger’s students, including Eugen Merzbacher, Ben Mottleson, Bertram Malenka, Walter Kohn, and Sidney Borowitz (the latter was not a student of Schwinger, but was a classmate of Schwinger at City College who became an instructor at Harvard; he and Kohn were Schwinger’s first assistants) gave a dinner party for Julian and Clarice. It was held at the Malenkas, who provided a home for the bachelors (Merzbacher, Kohn, Borowitz). 51 Clarice recalled that party fondly, remembering that Merzbacher had to cut the onions and cried; and that they borrowed Nancy Mottleson’s sterling silver. She recalled that it was a wonderful party and they had a very good time. 9 However, some of the students felt uncomfortable. ‘Nobody knew what to do with small talk,’ although apparently Julian was interested in old movies. ‘It was a delightful evening but everybody was a little bit apprehensive.’ 50 Clarice recalled that she was horrified to see Julian when they arrived go off in a corner by himself, seating himself in an empty chair. Eventually people came to him. 9 The Malenkas remembered that because they had only a three-room apartment with no bath, they had to take over the neighbor’s apartment. Beef Stroganoff and pecan pie were served, (p. 603 ) and after dinner they played charades—Julian was very good at it. At the end, everyone pitched in to do the dishes in the bathroom. 27 The Schwingers did not reciprocate by inviting the students over; Schwinger always maintained a gulf between the student and himself, * which could rapidly disappear once the degree was granted. The Schwingers were involved with Julian’s former students, Roy Glauber, Paul Martin, Bertram Malenka, Kenneth Johnson, and Stanley Deser; Clarice recalled that they went out or entertained, much more than they did in California, where they did very little. They saw each other fairly often. 9 Ruth and Bert Malenka recalled that in Fayerweather Street, Clarice started giving cocktail parties for his students. She would bake a cake for the occasion. The students would stay for hours, Clarice would keep bringing out more food, and Julian was charming. Later the Schwingers gave dinner parties, but these evenings evidently involved only selected students. 27 On the day Schwinger’s Nobel Prize was announced, the Malenkas recalled organizing a party at the Schwinger’s house. They brought over cases of wine, and all his students came and congratulated each other. 27 As we have documented, eventually the atmosphere at Harvard, where he had contributed so much to the building up of the faculty, turned against Schwinger. So much so, that by the late 1960s T. T. Wu could say, ‘Whatever Julian wants Julian doesn’t get’ 65 —so that he was not at all reluctant to leave for UCLA when David Saxon (through University of California President Kerr) again made him an offer in 1966. † Unfortunately, things started off rather badly at UCLA, and Schwinger was far less successful, or influential, there, than he had been at Harvard. David Saxon and Alfredo Banos were there, old friends from the days of the MIT Radiation Lab, as well as Robert Finkelstein, who had known Julian from the time of the Michigan Summer School in 1948, and his student Margaret Kivelson was in Planetary Sciences, but new friends were not forthcoming. The ways of the new superstar were not ingratiating. Alice Baños recalled that after only a year Nina Byers came up the hill to bring Julian a cake on his birthday. Clarice opened the door, said, ‘I’ve already baked him a cake,’ and closed the door. (This was not intended as a personal insult, but reflected the Schwingers’ intolerance of uninvited visitors. They were not used to casual California ways.) (p. 604 ) The department became angry with Schwinger because of his reclusive ways. He wouldn’t look at their problems or interact with them, merely slipping in for his classes, and escaping as quickly as possible. * ‘Why did we bring him?’ was the question among many of the faculty. 66 Schwinger may have asked himself the corresponding question, especially when he discovered that the caliber of the graduate students at UCLA was much lower than he had become accustomed to at Harvard. As a result, only a handful of students worked with Schwinger during the nearly two and a half decades he was at UCLA, an isolation which undoubtedly was reflected in his physics. † The bulk of his interaction at UCLA was with his assistants DeRaad, Milton, and Tsai, whom he had brought with him from Harvard. The last of these left in 1979, and was replaced for two years by Englert in the early 1980s. Correspondingly, his physics became increasingly iconoclastic. Even those students who felt misused by Schwinger admit his lasting influence. Horwitz summarized that influence well. ‘Schwinger’s serious deductive style deeply influenced me and the way that I deal with my own students. There is no question that all of his students (even Shelly !) were very much influenced by him in this way, and that, in addition to his incomparably important works, through this he has achieved a living immortality.’ 33 Judging by the results, Schwinger’s technique of educating graduate students was stupendously successful. Feynman was rather destructive toward his students, ‘while in his own way Julian really cared about his students. He gave them specific problems and offered useful advice when needed. Since his time was so precious, and he had such a high standard in research, we all did our best to figure out what we did not understand before we went to bother him with any questions. As a consequence, we became very independent. Another point is that we had to learn two approaches to physics, Schwinger’s way and the conventional way. This gave us an enormous advantage compared with other students.’ 64 Steven Weinberg offered some opinions as to why Schwinger was so much more effective than Feynman in educating graduate students. Like Max Born, ‘when you read the list of students you realize what an impact he had. Some of them were his students because they went to Harvard, but a lot of them went after him individually.’ ‘Feynman even to a greater extent than Julian was unwilling to take on the ordinary burdens of academic life. Feynman (p. 605 ) was even more of an obvious genius than Julian; with Julian it’s obvious he’s an intellectual, with Feynman he comes across as a longshoreman, and then you find out that he’s doing this very exciting and very inspired work, and the incongruity makes him seem even more of an awesome personality’ Feynman, along with Murray Gell-Mann, projected an overpowering aura at Caltech, so much so that some people had to leave. ‘Schwinger didn’t have that much of an aura.’ ‘Julian had a strong sense of duty,’ manifested, for example, in the care which he took toward his courses, and in his taking on graduate students; while Feynman ‘didn’t take duty that seriously,’ and only took on those tasks which appealed to him. 67 , * Tributes to Tomonaga and Feynman Schwinger gave two memorials to his fellow co-recipients of the Nobel Prize for the formulation of renormalized quantum electrodynamics, Sin-itiro Tomonaga, who died in 1979, and Richard Feynman, who died in 1988. Since these tributes reveal at least as much about Schwinger as they do about their subjects, we describe them in detail here. These accounts should be regarded as complementary to the descriptions of the careers of Tomonaga and Feynman given in Chapter 8 . Two shakers of physics Schwinger’s third visit to Japan was brief. † It was to honor the memory of his fellow recipient of the Nobel Prize, Shin-itiro Tomonaga. As Nishijima recalled, ‘In 1979 Tomonaga passed away. He had been the president of the Nishina Memorial Foundation and Ryogo Kubo succeeded the presidency. In 1980 Kubo asked Julian to deliver a lecture in memory of Tomonaga and Julian agreed. On 8 July 1980 he delivered the memorial lecture. It was impressive and touching. He emphasized various similarities in their works and careers. I knew that he worked very hard for the preparation of this lecture. Immediately after his arrival in Tokyo he stayed in his hotel and worked intensively day and night.’ 20 Clarice recalled that he almost wept on reading Tomonaga’s letters while preparing his address. (p. 606 ) Schwinger’s lecture was subtitled ‘Two shakers of physics’ . He opened his talk by explaining that title: ‘Immediately provocative is the curious similarity hidden in our names. The Japanese character—the kanji— shin has, among other meanings those of “to wave, ” “to shake.” The beginning of my Germanic name, Schwing , means “to swing,” “to shake.” Hence my title, “Two shakers of physics.”’ Schwinger began his lecture by recounting the history of modern physics in Japan. He described how Nishina returned from Copenhagen, lectured in Kyoto, and attracted Tomonaga to a research position in Tokyo in 1932. By 1933 Tomonaga was working on the positron and on quantum electrodynamics. Tomonaga had already been deeply influenced by Dirac’s 1932 paper 68 which proposed ‘to demote the dynamical status of the electromagnetic field,’ ultimately ‘a false trail.’ Tomonaga independently, and perhaps earlier, proved, but did not publish, the equivalence to the Dirac theory and the Heisenberg– Pauli theory, 69 an equivalence demonstrated by Rosenfeld 70 and by Dirac, Fock, and Podolsky. 71 Schwinger then drew some further historical parallels. ‘I graduated from a high school that was named for Townsend Harris, the first American consul to Japan. Soon after, in 1934, I wrote but did not publish my first research paper. It was on quantum electrodynamics.’ Here he used the Dirac–Fock–Podolsky formulation to describe the retarded Møller interaction. 72 ‘But now, since I was dealing entirely with fields, it was natural to introduce for the electron field, as well, the analogue of the unitary transformation that Tomonaga had already recognized as being applied to the electromagnetic field in Dirac’s original version. Here was the first tentative use of what Tomonaga, in 1943, would correctly characterize as “a formal transformation which is almost self-evident” and I, years later, would call the interaction representation. No, neither of us, in the 1930s, had reached what would eventually be named the Tomonaga–Schwinger equation. But each of us held a piece which, in combination, would lead to that equation: Tomonaga appreciated the relativistic form of the theory, but was thinking in particle language; I used a field theory, but had not understood the need for a fully relativistic form. Had we met then, would history have been different?’ . In 1936 Tomonaga turned his interest to nuclear physics, and the following year went to Heisenberg’s institute in Leipzig for two years. Tomonaga, like everyone else in the field then, was thoroughly confused by the misidentification of the meson observed at sea level (now called the muon) with Yukawa’s meson that carried the strong force (now called the pion). He had an indirect scheme to explain the disparate properties, particularly the long lifetime of the muon, and Tomonaga became rather depressed with his slow progress, which Schwinger documented with eloquent quotations from Tomonaga’s diary. Toward the end (p. 607 ) of his stay in Leipzig, Heisenberg presented him with the idea that strong field interactions might act to suppress the scattering of mesons by nucleons; Tomonaga wanted to extend his stay in Leipzig to follow this up with a quantum-mechanical calculation, but the threat of war forced him to return home. As it turned out, Yukawa was on the same ship crossing the Atlantic, and disembarked at New York, visiting many universities in America, beginning with Columbia, where he and Schwinger first met. But Tomonaga was so homesick for Japan that he stayed on the ship all the way to Japan. When Tomonaga got home, he started working on Heisenberg’s proposal, and then became aware that Wentzel had also attacked the problem of strong coupling. 73 Remarkably, Schwinger was thinking along the same lines at the time in Berkeley. Schwinger found an error in Wentzel’s calculation. ‘In the short note that Oppenheimer and I eventually published , this work of mine is referred to as “to be published soon.” And it was published, 29 years later, in a collection of essays dedicated to Wentzel . Recently, while surveying Tomonaga’s papers, I came upon his delayed publication of what he had done along the same lines. I then scribbled a note: “It is as though I were looking at my own long-unpublished paper.” I believe that both Tomonaga and I gained from this episode added experience in using canonical-unitary-transformations to extract the physical consequence of a theory.’ Schwinger then went on to describe the erroneous Dancoff calculation of 1939. 74 Dancoff calculated the electrodynamic correction to scattering both for spin-0 and for spin-½ charged particles. The former gave a finite correction, while the latter gave an infinite one, in contradiction with the expectation that the electromagnetic mass shift for spin- ½ particles should be much less strongly divergent than that for spin-0 particles. But in 1939 and 1940 Tomonaga was still dealing with mesons. He showed that negative mesons should preferentially be absorbed by matter, but later experiments showed no significant interaction for either sign of meson. For the next two years he worked on various strong and intermediate coupling meson theories. By the end of 1943, Sakata presented at the Meson Symposium his suggestion that the two mesons were not the same. 75 But in the spring of that year Tomonaga presented a paper at the last meeting of the Riken, on the ‘Relativistically invariant formulation of quantum field theory.’ Tomonaga believed that he could solve both the problem of lack of relativistic covariance and the infinities of field theory simultaneously. This talk was followed by a paper published in the Bulletin of the Institute, Riken-Iho. 76 This paper was unknown outside Japan until it was translated into English and published in the second (August–September) issue of Progress of theoretical physics , in 1946. 77 Even that paper was unknown in America and Europe until well after the Shelter Island Conference. In this paper Tomonaga pointed (p. 608 ) out that the canonical equal-time commutation relations, and the Schrodinger equation, were not covariantly formulated. However, formulating commutation relations between fields on an arbitrary space-like surface presents no difficulty if there are no interactions. Even with interactions this can be achieved, if the interactions are removed by a unitary transformation, that is, by passing to the interaction representation. It is more complicated to generalize the Schrödinger equation. This was accomplished by Tomonaga by generalizing Dirac’s many-time theory, 68 or the theory of Dirac–Fock–Podolsky, 71 in which ‘each particle is assigned its own time variable.’ ‘The Schrödinger equation, in which time advances by a common amount everywhere in space, should be regarded as describing the normal displacement of a plane space-like surface. Its immediate generalization is to the change from one arbitrary space-like surface to an infinitesimally neighboring one, which change can be localized in the neighborhood of a given space–time point. Such is the nature of the generalized Schrödinger equation that Tomonaga constructed in 1943, and to which I came toward the end of 1947.’ At this point Tomonaga’s fundamental work was interrupted by the war. Like Schwinger, an ocean and a continent away, he began to work on radar. Tomonaga had to match the language of physicists—Maxwell’s equations—to the language of the electrical engineers, namely notions such as impedance. A key step in Tomonaga’s development was the delivery by German submarine of a Top Secret dispatch, which turned out to be Heisenberg’s paper on the scattering matrix. 78 Schwinger drew strong parallels with his own development. ‘I would like to think that those years of distraction for Tomonaga and myself were not without their useful lessons. The waveguide investigations showed the utility of organizing a theory to isolate those inner structural aspects that are not probed under the given experimental circumstances. That lesson was soon applied in the effective range approximation of nuclear forces. And it is this viewpoint that would lead to the quantum electrodynamics concept of self-consistent subtraction or renormalization.’ Schwinger then recounted his major lesson from his study of synchrotron radiation at the end of the war, wherein a properly covariant electromagnetic contribution to the electron’s mass appeared. ‘Moral: to end with an invariant result use a covariant method and maintain covariance to the end of the calculation. And, in the appearance of an invariant electromagnetic mass that simply added to the mechanical mass to form the physical mass of the electron, neither piece being separately distinguishable under ordinary physical circumstances, I was seeing again the advantage of isolating unobservable structural aspects of the theory’ After the war was over, Sakata proposed the notion of the field of a cohesive force which could cancel the infinite electromagnetic mass effect. 79 Tomonaga (p. 609 ) took this idea up as a promising development. Although it was later shown that this could not work beyond lowest order, the ‘C-meson hypothesis served usefully as one of the catalysts that led to the introduction of the self-consistent subtraction method.’ Tomonaga’s group used this method to recalculate Dancoff’s 1939 result 74 on electron scattering corrections. Employing a much improved, covariant method that used ‘a unitary transformation that immediately isolated the electromagnetic mass term’ Tomonaga discovered that Dancoff had, as Tomonaga’s group had initially, overlooked a term; the resulting correction was finite! That is, it was finite ‘except for a divergence of the vacuum polarization type.’ As Schwinger noted, this divergence could be absorbed into a redefinition of the charge. What was needed to proceed was experimental guidance. Such guidance was provided by the results on the Lamb shift, and on the anomalous magnetic moment of the electron announced at the Shelter Island Conference. This information only reached Japan through the popular science column of Newsweek . Tomonaga was then immediately able to use his ‘covariant contact transformation’ method, which had worked so well in uncovering Dancoff’s error in electron scattering, to the Lamb shift, providing a relativistic calculation justifying Bethe’s approximate non-relativistic estimate. 80 This result was announced by Tomonaga at the Kyoto symposium in November 1947, calling the method the ‘self-consistent subtraction method.’ ‘And so, at the end of 1947, Tomonaga was in full possession of the concepts of charge and mass renormalization.’ The date that Tomonaga communicated his results on elastic electron scattering, 81 30 December 1947, was the same as when Schwinger sent in his paper on his calculation of the anomalous magnetic moment of the electron . ‘Here I held an unfair advantage over Tomonaga, for owing to the communication problems of the time, I knew that there were two kinds of experimental effects to be explained: the electric one of Lamb, and the magnetic one of Rabi.’ In that note, Schwinger also pointed out that radiative corrections to electron scattering came out finite, and that the relativistic calculation of the Lamb shift was consistent with that of Bethe. The vagueness of the latter remark reflected Schwinger’s awareness that his calculation was wrong, in that the relativistic analog of the anomalous magnetic moment came out incorrectly: ‘relativistic invariance was violated in this non-covariant calculation.’ We have recounted this error, and the impetus it provided Schwinger to develop a covariant formulation, in Chapter 8 . At the January 1948 APS meeting Schwinger mentioned this difficulty, remarked that he now had a covariant formulation, * and learned (p. 610 ) from Oppenheimer that Tomonaga had discovered the same description at least four years previously. In April 1948 Tomonaga wrote to Oppenheimer and sent him a collection of manuscripts. Oppenheimer telegraphed back encouraging him to write up a summary of his work, which he would arrange to have published in Physical Review . At the end of May, Oppenheimer received the summary, and sent it to the journal, along with a clarifying note. 82 That note refers to a difficulty Tomonaga had with what appeared to be a photon mass: Oppenheimer quoted Schwinger, in effect, stating that a sufficiently careful treatment should yield a zero photon mass. Tomonaga was not convinced by this argument; ‘and he was right, for the real subtlety underlying the photon mass problem did not surface for another ten years, in the eventual recognition of what others would call “Schwinger terms.” ’ Schwinger mentioned that at this same time Tomonaga was also involved in cosmic ray research. Tomonaga published a paper with Satio Hayakawa on the deeply penetrating muon in 1949; 83 in the same year he published a book on quantum mechanics, 84 and came for a visit to the Institute for Advanced Study at Oppenheimer’s invitation. There he worked on the quantum many-body problem, which Schwinger would turn to many years later. But after Tomonaga’s return to Japan, he soon had to assume Nishina’s administrative duties upon the latter’s death in 1951. He became President of the Tokyo University of Education in 1956, then the President of the Science Council of Japan in 1962, and in 1964 President of the Nishina Memorial Foundation. He retired in 1970 and wrote a couple of popular books on science. In this, too, Schwinger found a parallel with his own career, in this case with his BBC/Open University series on relativity. As we see, Schwinger used much of his lecture on Tomonaga’s career to advertize his own. In part, this was entirely justifiable in view of the striking parallels in their paths; Tomonaga’s covariant approach to quantum electrodynamics anticipated many essential features of Schwinger’s. If the experimental impetus had been available in Japan, Tomonaga’s group might well have solved the problems of quantum electrodynamics first. But as we saw in detail in Chapter 8 , Schwinger was deeply skeptical of that possibility, and because he did not esteem Tomonaga’s contributions too highly, he found it very difficult to write this memorial lecture. That appears to be the true reason for the excessively self-referential tone. (p. 611 ) A path to quantum electrodynamics On 15 February 1988 Richard Feynman died after a long and painful battle with cancer. * A month later, Julian celebrated his 70th birthday with a conference in his honor at UCLA, which he dedicated to Feynman’s memory. † Although the two had never worked together, and had only intermittent contact, ‡ they respected each other deeply; Julian Schwinger was greatly moved, indeed devastated, by Feynman’s death. A year later Physics Today , the semipopular professional magazine of the physicists, devoted a special issue to Feynman. 87 It included contributions by many of Feynman’s friends and colleagues: John Wheeler, Freeman Dyson, Murray Gell-Mann, James Bjorken, David Goodstein, Daniel Hillis, and Valentine Telegdi. Of course, Julian Schwinger wrote about Feynman’s contributions to quantum electrodynamics. Schwinger tried to capture Feynman’s voice by quoting extensively from the latter’s Nobel lecture. Schwinger started by recalling their first meeting, when he visited Los Alamos from the MIT Radiation Laboratory to talk about waveguides and synchrotron radiation. Feynman looked glum. ‘He began to lament the loss of irreplaceable time to do physics, of which I was keenly aware; we were both 27 years old. He said something like, “I haven’t done anything, but you’ve already got your name on something.” I still wonder what he was referring to.’ But, as Schwinger pointed out, Feynman by that point had done quite a lot. He had begun to think about the problems of self-action of the electron, first, as an undergraduate at MIT, suggesting that electrons cannot act on themselves, but then, as a graduate student at Princeton, realizing that self-action was necessary to understand radiation resistance, required by energy conservation. With Wheeler, Feynman came up with the idea of replacing classical retarded electromagnetic interactions with ‘an action-at-a-distance electrodynamics … that is half retarded, half advanced…. It was equivalent to the retarded description and contained the radiative resistance force, provided one assumed that any (p. 612 ) emitted radiation was totally absorbed within the complete system of charges.’ They had also found that the symmetrical solution, unlike the retarded solution, admitted an action-principle formulation, as Adriaan Fokker had observed in 1929. 88 Feynman gave a lecture on this classical theory at Princeton, which was projected to be followed by Wheeler’s talk on the corresponding quantum theory; Pauli correctly predicted that that talk would never be given. Also, at the classical level they suggested a modification of the electrodynamic interaction, replacing the delta function that enforced the interaction of a charged particle through a light signal traveling on the light cone by a smooth function f , which would make self-action finite; the ‘“main effect of this self-action was a modification of the mass.” ’ Feynman had already achieved an integral approach, with an action that described the particle’s entire path through space–time. Schwinger next went on to describe Dirac’s famous 1933 paper on ‘The Lagrangian in quantum mechanics.’ 89 Dirac advocated the use in quantum mechanics of the Lagrangian, which is expressed in terms of particle coordinates and velocities, rather than the Hamiltonian, expressed in terms of coordinates and momenta. He viewed the former as more fundamental. Dirac, of course, was the inventor of transformation theory. The transformation function from a description at time t 2 to a description at time t 1 is ‘the product of all the transformation functions associated with the successive infinitesimal increments in time.’ Dirac said the latter, that is, the transformation function from time t to time t + d t, corresponds to exp , where L is the Lagrangian expressed in terms of the coordinates at the two times. For the transformation function between t 2 and t 1 ‘the integrand is exp , where W = ∫ t 1 t 2 d t L . ’Now we know, and Dirac surely knew, that to within a constant factor the “correspondence,” for infinitesimal d t , is an equality when we deal with a system of nonrelativistic particles possessing a coordinate-dependent potential energy V …. Why, then, did Dirac not make a more precise, if less general, statement? Because he was interested in a general question: What, in quantum mechanics, corresponds to the classical principle of stationary action?’ ‘Why, in the decade that followed, didn’t someone pick up the computational possibilities offered by this integral approach to the time transformation function? To answer this question bluntly, perhaps no one needed it—until Feynman came along. He has described how, at a Princeton beer party, he was accosted by Herbert Jehle, newly arrived from Europe, who wanted to know what Feynman was working on. After telling Jehle about his struggles with electrodynamics, Feynman turned to Jehle and asked, “Listen, do you know any way of doing quantum mechanics starting with action?” As it happened, Jehle was aware of Dirac’s early paper, and so Feynman found what he (p. 613 ) wanted, a formulation of quantum mechanics that could be applied to his classical action-at-a-distance electrodynamics—if one took for granted that Dirac’s construction still worked when a Lagrangian did not exist. Feynman called this approach to quantum mechanics the path integral formulation because a value of the action W is assigned to any sequence of intermediate coordinate values—to any path between the initial and the final coordinates—and all such values of exp are added together.’ At this point Feynman could only describe electrons nonrelativistically. While he was at Los Alamos during the war, Feynman continued to think about these matters at odd moments, and discovered that his scheme did not conserve probability. He also made no attempt to do any actual calculations: ‘“I hadn’t even calculated the self-energy of an electron up to that point , and was studying the difficulties with the conservation of probability, and so on, without actually doing anything, except discussing the general properties of the theory.” ’ After the experimental results were announced at Shelter Island, Feynman realized he had to learn how to do calculations. He still did not have a rel-ativistic theory of electrons. He had to guess the form of the description of spin-½ electrons, and determine the relative signs empirically. ‘“I have tried to explain that all the improvements of relativistic theory were at first more or less straightforward, semi-empirical shenanigans. Each time I would discover something, however, I would go back and I would check it so many ways … until I was absolutely convinced of the truth of the various rules and regulations which I concocted to simplify all the work.” ’ Feynman then published his results, 90 even though he could not justify his procedure. ‘“Often, even in a physicist’s sense, I did not have a demonstration of how to get all of these rules and equations, from conventional electrodynamics. But, I did know from experience, from fooling around, that everything was, in fact, equivalent to the regular electrodynamics and had partial proofs of many pieces, although, I never really sat down, like Euclid did for the geometers of Greece, and made sure that you could get it all from a single simple set of axioms. As a result, the work was criticized, I don’t know whether favorably or unfavorably, and the ‘method’ was called the ‘intuitive method.’ For those who do not realize it, however, I should like to emphasize that there is a lot of work involved in using this ‘intuitive method’ successfully. Because no simple clear proof of the formula or idea presents itself, it is necessary to do an unusually great amount of checking and rechecking for consistency and correctness in terms of what is known…. In the face of the lack of direct mathematical demonstration … one should make a perpetual attempt to demonstrate as much of the formula as possible. Nevertheless, a very great deal more truth can become known than can be proven.” ’ (p. 614 ) Feynman was still concerned, at the time of his Nobel lecture, with the failure of unitarity. ‘With δ replaced by f the calculations would give results … for which the sum of the probabilities of all alternatives was not unity…. I believe there is really no satisfactory electrodynamics, but I’m not sure. Therefore, I think that renormalization theory is simply a way to sweep the difficulties of the divergences of electrodynamics under the rug. I am, of course, not sure of that.” ’ Feynman retained this skepticism about renormalization to the end of his life, a doubt that Schwinger did not share. The concluding paragraphs of Schwinger’s article consisted almost entirely of quotations from Feynman’s Nobel lecture: ‘It is most striking that most of the ideas developed in the course of this research were not ultimately used in the final result. For example, the half-advanced and half-retarded potential was not finally used, the action expression was not used, the idea that charges do not act on themselves was abandoned. The path integral formulation of quantum mechanics was useful for guessing at final expressions and at formulating the general theory of electrodynamics in new ways—although, strictly, it was not absolutely necessary. The same goes for the idea of the positron being a backward moving electron; it was very convenient but not strictly necessary. ‘On looking back over the work, I can only feel a kind of regret for the enormous amount of physical reasoning and mathematical re-expression which ends by merely re-expressing what was previously known, although in a form which is much more efficient for the calculation of specific problems…. It must be remarked that although the problem actually solved was only such a reformulation, the problem originally tackled was the (possibly still unsolved) problem of avoidance of the infinities of the usual theory. Therefore a new theory was sought, not just a modification of the old. Although the quest was unsuccessful, we should look at the question of the value of physical ideas in developing a new theory. ‘Theories of the known, which are described by different physical ideas, may be equivalent in all their predictions and are hence scientifically indistinguishable. However, they are not psychologically identical when trying to move from that base into the unknown…. If every individual student follows the same current fashion in expressing and thinking about , then the variety of hypotheses being generated to understand is limited. Perhaps rightly so, for possibly the chance is high that the truth lies in the fashionable direction. But it is in another direction, who will find it?’ Schwinger concluded this tribute with his own words: ‘So spoke an honest man, the outstanding intuitionist of our age and a prime example of what may lie in store for anyone who dares to follow the beat of a different drum.’ (p. 615 ) Although moving, these tributes to Tomonaga and Feynman appear rather stiff and formal. And indeed, when he gave the memorial lectures in Tokyo and San Francisco, respectively, his presentation was quite properly formal, consisting of standing at a lectern and reading from a prepared text. Thus he conveyed none of the excitement of his classroom lectures on physics, which were well rehearsed, but delivered without notes. Part of Schwinger’s perceived coldness was based on his view of physics. His lectures on Tomonaga and Feynman, as his other historical lectures, largely consisted of quotations. Eugen Merzbacher, who was President of the American Physical Society when the Feynman tribute was organized, * remarked that ‘he didn’t want to involve the human being in physics, for that would spoil the esthetics.’ 51 Celebration of his life Historical and philosophical talks In addition to the tributes to Feynman and Tomonaga we have outlined above, Schwinger gave a number of historical and philosophical talks in the last two decades of his life. In Chapter 14 we have described the talk on ‘Conflicts in physics’, given at several places and referring to the role played by two relatively unknown scientists in the development of the atomic theory and the suppression of their ideas by the scientific establishment. † In the early 1960s he gave a nontechnical lecture on his philosophy of quantum mechanics and quantum field theory. 39 There, he expounded his current view of microscopic phenomena, with the distinction between particles (phenomenological) and fields (fundamental), a view elaborated a few years later in his Nobel Lecture. This interesting talk has been analyzed in detail in Schweber’s book. 92 Harvard University regularly sponsors a major series of public lectures, the Loeb Lectures, which feature popular talks by leading scientists. One month, in the mid-1970s, Paul Dirac and Julian Schwinger were Loeb Lecturers at (p. 616 ) different ends of the month. The gist of Dime’s talk was ‘always trust the mathematics, the physics is too murky,’ while Schwinger said, in effect, ‘never rely on mathematics, keep your eye glued to the physics.’ But Schwinger, for all his strong phenomenological bent, is remembered for his formalism, while Dirac mistrusted his mathematics of the Dirac equation to believe that the negative energies solutions were the proton, not the anti-electron. 93 One of the most remarkable talks of this kind was delivered only once, on 12 April 1973 at UCLA on the subject of Leonardo da Vinci. The handwritten manuscript exists in the UCLA archive. 39 As this brief lecture is revealing of Schwinger’s attitude toward science, we shall quote it in full. ‘By the XV century the fragmentary remains of mankind’s intellectual heritage had largely come to light and were increasingly available in the vernacular. The concomitant renaissance of learning had one unfortunate tinge, however. Contemporary man was overawed by the accomplishments of the ancients and their works tended to be placed on such a lofty pedestal that, in effect, one Authority was replaced by another. It was Leonardo more than any other who began the transformation of this backward looking adoration of the classical period with the forward looking modern scientific viewpoint—that only through the direct observation and probing of nature can objective knowledge be acquired. He said, for example, “Whoever in discussion adduces authority uses, not his intellect, but rather memory.” Nevertheless the classical texts were of great importance to him and he read widely among them. Yet it is revealing that he was particularly attached to Archimedes for, among the Greek founders of physics, he was unique in avoiding the danger of mixing philosophical (a priori) concepts with scientific reasoning. Rather, he also proceeded in the modern manner, in which a few relatively simple facts are, through the power of mathematical analysis, made the foundation of a logical structure that encompasses wide areas of experience. Observation combined with mathematical reasoning is the cornerstone. And Leonardo said, “there is no certainty where one cannot apply any of the mathematical sciences.” ‘It is fascinating to read among the notebooks the bits and fragments that show how far he was in advance of his age. At a time when the Ptolemaic geocentric doctrine was universally accepted, and at least 20 years before the publication of Copernicus, we read, “The sun does not move.” Again, we find the memorandum “Construct glasses to see the moon large.” This, one hundred years before Galileo! Let me emphasize the epistomological point here. Leonardo was saying this, I believe: Disregard the speculations of Aristotle, for example, on the structure of the moon—rather, use your own senses, amplified by the power of scientific instruments. Here is modern science indeed! In a study of bird flight: “All movement tends to be maintained.” And: “Nothing whatever can be moved by itself, but its motion is affected by another. This other is force.” (p. 617 ) And finally: “An object offers as much resistance to the air as the air does to the object.” The last is stated as a special case, and the language begs for scientific precision, but do we not have here the essence of the three laws of motion, 150 years before Newton? ‘The great tragedy of all this, as you know, is that none of this marvelous insight and pioneering of new paths had the slightest influence on the actual evolution of science, with a possible exception that I shall mention later. It remained locked in the notebooks to be finally appreciated only several centuries after its revelation had been duplicated, and surpassed. It is idle to speculate how it might otherwise have been, if Leonardo had obeyed the modern injunction to Publish or Perish. He did neither. Would another Newton have appeared a century earlier? Or is it inexorable to wait on the fullness of time, until the roots have dug deeply enough to bear the next growth? Leonardo himself said: “Truth is the daughter of time.” I wonder, incidentally, how many of you had a feeling of recognition on hearing that last phrase? Yes, part of it, the Daughter of Time , is the wonderfully apposite title selected by Josephine Tey for a delightful detective-historical study of Richard III and his slandered reputation. ‘I have spoken of the modern character of his thinking. Nothing could be more modern than the moral conflicts he encountered in applying his technological knowledge to the engines of warfare, as Archimedes had done before him. But it was uniquely reserved to Leonardo to solve this problem in a particular way. After mentioning the possibility of constructing submarines that could stay underwater for as long as the crew could “remain without food” as he put it, he says, “this I do not publish or divulge, on account of the evil nature of men, who would practice assassinations on the bottom of the sea.” And so they did, but only several centuries later. For us, unfortunately, technological censorship, whether self or externally imposed, is no longer an answer. That can only come when man has learned to hold in check his “evil nature.” ‘Having broached the subject of technology, let me turn to Leonardo the engineer. In his time, science and technology, principle and application, were not differentiated as they are today. Leonardo himself, starting as a gadgeteer, a trial and error empiricist, was driven to study and develop the mechanical principles that underlie and extend practical experience. I only mention his work on rolling friction, on pulleys, on gears, on the loading of structures. But let me briefly discuss his possible connection with the actual development of the steam engine. He designed and used the first steam calorimeter, in order to measure the expansion power of steam, which device incorporated a piston, driven by that power. Many years later some of these related ideas were published in similar form by Jerome Cardan (I use the English form of his name) who was notoriously light-fingered with other people’s intellectual property and who, through his father, a personal friend of Leonardo, had direct access to (p. 618 ) the notebooks. There is more to the gossip, but I shall leave you with only the suggestion that, in this instance at least, Leonardo’s pioneer work many not have been entirely wasted. ‘The same Jerome Cardan was also not above a bit of malicious gossip, as when he wrote “Leonardo also attempted to fly but misfortune befell him from it. He was a great painter.” The reference is, of course, to Leonardo’s fixed preoccupation with the flight of birds and the attainment of artificial flight. Unfortunately, Leonardo’s obsessive desire to have man fly preceded the scientific study of bird flight, and was based on the erroneous notion that flapping wings, driven by man’s muscle power alone, would suffice. Only later, after studying the soaring flight of birds, and appreciating some of the physical principles of wing design, did he approach the ideas of fixed wings and mechanical power. But by then it was too late. Nevertheless, he did invent the parachute and produce a mechanically driven helicopter design. ‘As Cardan noted, he was a great painter. But art and science were not two different cultures for Leonardo, nor should we accept that artificial dichotomy. Leonardo said, “Painting, the sole imitator of all the visible works of nature, is truly a science and the time-born daughter of nature.” Art and science, then, are simply two different paths to the study and understanding of nature, which is the great teacher. The humanism of which we spoke had its greatest impact on literature. Very little of classical art had survived, and humanism took a more original turn when it focussed on painting and sculpture. And it was the desire of the artists to improve their command over materials and techniques that finally brought humanism to science. In Leonardo’s case, the preliminary sketches and studies for paintings and sculptures led inexorably through anatomical and other investigations to the preoccupation with the universal laws of Nature that govern all things, animate and inanimate. Would that the world’s loss, when he was drawn away from painting, had been recompensed by the enormous impetus to physical and anatomical knowledge that publication of the notebooks would have produced.’ Thus ended Schwinger’s tribute to Leonardo. Schwinger gave a few other pronouncements on the importance of the scientific method. In a conference discussion with Glenn Seaborg, John Eccles, and other leading scientists, Schwinger had an eloquent statement for the values of science. 39 ‘Too often scientists, in justifying what they do and why society as a whole should support that effort, point to all the practical benefits that come from it. It’s well known that for every dollar, ten dollars, or whatever the number may be, will be returned to the community as a whole. But that is not the fundamental reason science is done. I think science should be supported basically for the same reasons that symphony orchestras are supported. There is no economic return from this, but we all know its cultural importance. So I would emphasize the other side of the coin—the spiritual, the cultural values.’ (p. 619 ) The discussion took place about the time that the Fermilab accelerator was being planned. ‘I agree that it is difficult to convey to the public at large why this particle accelerator is desirable, but I do believe it is possible and in fact mandatory to convey to the public at large the thrill of this hunt, the intellectual, and to some extent, the practical importance of it…. Surely a feeling of the mystery and the awe of nature that goes with this can be transmitted.’ 39 In a similar vein, Schwinger pleaded for the communication of the scientific attitude in a historical session with Rabi and others held in November 1985. 39 ‘ Science is a world view. And a world view based on a method, and a method that everyone can apply in his own life. I mean, in his life activities of skepticism, of testing, and so forth. And that’s what we have to convey to the population at large, not the detailed discoveries and so forth, but the intellectual attitude. And it is communicable. And we are failing to do it.’ 39 One of Schwinger’s most eloquent statements of the importance of research was published in 1964 . We quote it in full: ‘The scientific level of any period is epitomized by the current attitude toward the fundamental properties of matter. The world view of the physicist sets the style of the technology and the culture of the society, and gives direction to future progress. Would mankind now stand on the threshold of the pathway to the stars without the astronomical and mechanical insights that marked the beginning of the scientific age? The quest for understanding has led outwardly to the galaxies and inwardly to the atom and then to the nucleus. Now it is the subnuclear world that is being actively explored. The goal here is not merely an organizing principle for subnuclear particles, a new periodic table of the elements, interesting and important as that may be. Rather we are groping toward a new concept of matter, one which will unify and transcend what are now understood only as separate and unrelated aspects of natural phenomena. In past triumphs, physics has unified light with electromagnetism, mass with energy, and comprehended chemistry and the mechanical–thermal properties of bulk mater in the atomic laws of quantum mechanics. But the fundamental problems remain. What is the role of gravitation in coupling the remote stars to the atom? Can one understand the magnitude of the unit of electrical charge? These are traditional queries. Recent research has provoked a whole battery of additional questions. What is the relation between the newly revealed internal degrees of freedom and space–time? How can one connect the diverse interactions, of different strengths and characteristics, that are required to account for the birth and death of subnucleonic particles? ‘But perhaps the most important question concerns whether these particles must be accepted as basic and unanalyzable, to be described only in their own framework, or whether there exists a simple and more fundamental substructure, a deeper level of description and understanding. There alternatives have (p. 620 ) been presented before in the history of physics. At the close of the 19th century it was strongly argued that the properties of bulk matter should not be accounted for by the characteristics of unobservable and hypothetical microscopic entities. Owing to the continued development of experimental technique, this limited viewpoint had to be discarded and the atomic theory triumphed. A similar decision can be given again only if the tools will be at hand to continue the penetration into the totally new, totally unpredictable world of the microcos-mos. And one should not overlook how fateful a decision to curtail the continued development of an essential element of the society can be. By the 15th century, the Chinese had developed a mastery of ocean voyaging far beyond anything existing in Europe. Then, in an abrupt change of intellectual climate, the insular party at court took control. The great ships were burnt and the crews disbanded. It was in those years that small Portuguese ships rounded the Cape of Good Hope.’ Schwinger’s death and tributes After Julian was diagnosed with pancreatic cancer, Clarice told relatively few friends. * A letter to the Baños’ was misaddressed, so they never knew he was ill until Clarice called Alice to tell her Julian had died that morning. But the Kivel-sons knew of the illness. Margaret and Daniel visited Julian in the hospital near the end. ‘Unfortunately, when he was in the hospital, he was really miserable, very, very sick, very brave. I think he was glad that we had come. I don’t think Clarice let many people come. It was really so fast, nobody would believe it. We were grateful that Clarice gave us a chance to say goodbye.’ 28 Seth Putterman also visited him two days before his death. ‘He did not want to talk about history but about physics.’ So Seth told him of the remarkable fact that sonoluminescence requires about a 1% admixture of noble gas in the air, and that water was the most favorable liquid. Julian thought for a moment, and remarked, ‘It probably has something to do with evolution.’ 95 Schwinger died on 16 July 1994 feeling unappreciated. David Saxon reflected on this. ‘What was Julian hungering for? Was it more recognition or the demanding job of living up to his own standards? The “Greening of quantum field theory” was a wonderful paper in many ways, but kind of sour. Recognition was a big deal.’ 8 (p. 621 ) A month after Julian’s death, in August 1994, Clarice held a memorial service in her home. A few of his old friends and colleagues were able to attend. These included David Saxon, Paul Martin, Robert Finkelstein, and others, and informal moving tributes were offered. More publicly, in the year after his death in July 1994 three special physics gatherings were held in his honor. The first was organized by Abe Klein at Drexel University in September. That symposium was noteworthy for the eloquent reading by Freeman Dyson of Schwinger’s last public lecture, ‘The Greening of quantum field theory: George and I’ given at Nottingham on his award of an honorary degree in 1993 . * (This was discussed in detail in Chapter 9 .) The second meeting was organized by David Saxon and held at UCLA in October, while the third was held at the joint meeting of the American Physical Society and the American Association of Physics Teachers in Washington in April 1995. The talks given in these public symposia were collected in a volume edited by Jack Ng. 18 We have quoted extensively from these tributes throughout this book. A year or so after his death, Clarice delivered a moving summary of their life together. It seems fitting to end this book by quoting it in full, since Clarice and Julian were nearly inseparable for 47 years. ‘Nostalgia was not one of Julian’s strong points, but whenever the subject of Columbia came up, he spoke of it with warmth and affection. ‘I came into the world of physics a complete and utter stranger. ‘Shortly after our engagement, a friend lent me a novel describing extramarital affairs among members of the English and History Departments at Harvard. I remember that when I returned it, I said, “Maybe in English and History, but not in Physics.” ‘Then came the introduction of the Hamiltonian, Green’s functions, and my favorite, magnetic moment—surely a better name for a perfume than Poison. ‘Life with Julian was fun. While his very being was immersed in the wonder and beauty of physics, he was interested in, and cared deeply about, many things—the country, our constitution, the environment, people both collectively and individually, music, skiing, tennis, travel, poetry, archaeology, (p. 622 ) languages. Among his happiest language lessons were those in Mayan given him by a guide when we were in the Yucatan. I have always maintained that when traveling in foreign countries every family should have one person to speak the required language. In our family, it was he. (I would point, smile, and pay.) ‘For some time he continued his diet of steak and chocolate ice cream, even as he encouraged me to order all manner of exotic dishes. In due time, however, he became much more adventurous than I; and to his delight developed a discerning palate for wine. ‘Soon after we were married, he began piano lessons. The first year with a New England Conservatory disciplinarian, and then with a Longy School teacher who taught sight reading. While he didn’t become a Weisskopf or a Francis Low, he played well enough to afford himself pleasure and caused us no suffering. I recently received a note from a woman who lived across the street during our first temporary year in LA, saying how much she had enjoyed hearing him play at one in the morning. Talk about kindness! ‘On our honeymoon we drove across the country, stopping at all the schools at which he had consumed hamburgers and chocolate milk shakes. When we came to Pikes Peak we got out of the car, cameras in hand. He had to photograph his beloved mountains, I, to take a picture of a tiny wild flower on my side of the car. He, with his long vision, I with one short as my nose. ‘As McCarthyism fever mounted, I immediately went into sack cloth and ashes. Not Julian, he was confident that the American people would not tolerate it, and he was right. ‘He loved teaching and enjoyed interacting with his some 70 students, two of whom became Nobelists. He was really a quite wonderful lecturer. I would attend his talks at various meetings and sometimes think if only I’d pay attention I would understand what he was saying. Instead, I would sit in back of the hall, watch the audience, and be able to tell him that even though he might feel he’d not done well enough, with rare exceptions his audience had genuinely enjoyed his talk. I could hear them say as much on their way out. Someone has apparently said that Schwinger did what he did to show that only Schwinger could do it. What a donkey! Not to understand the joy of accomplishment and the passionate excitement of sharing it. ‘We both took up skiing. After a few years I made a subtle statement—I purposely left my boots behind at the end of a sabbatical in Japan. They hurt. Not Julian. His boots hurt, too, but he stayed with it and became a good intermediate skier. ‘It took a bit of doing to get used to physics parties. Almost as soon as we came in, some physicist would aim and pierce Julian to a wall and tell him about his own work. A pale Julian would emerge, to be revived at dinner by sitting between two women and having an interesting and amusing exchange. He did (p. 623 ) well with women and children … and cats. A little niece was asked why she loved Uncle Julian and she said, “Because he listens.” ‘He changed my life in many ways. For one thing, I didn’t have to know very much. I had only to ask him and I’d have the answer. Sometimes we resorted to a reference source but more often than not he would simply tell me. ‘Before 8 June 1947, I was an early to bed, early to riser. After that date a note was pasted above our door bell, “Please do not ring before 11 a.m.” Then he succumbed to the lure of Southern California and year round tennis. He was told that he must not eat for two hours before playing. Suddenly 25 years of training was for naught. Breakfast appeared at 8:30 to accommodate an 11 o’clock tennis date. ‘He had extraordinary perception and understanding, keen wit and delightful sense of humor. He was honest, kind, and generous. ‘The world that knew him will never be the same.’ 96 Bibliography references: 1. UCLA Monthly , November 1973. 2. Personal papers of Julian and Clarice Schwinger. 3. Bernard Feld, talk at banquet at Schwinger’s 60th Birthday Celebration, February 1978 (AIP Archive). 4. Julian Schwinger, conversations and interviews with Jagdish Mehra, in Bel Air, California, March 1988. 5. Herman Feshbach, telephone interview with K. A. Milton, 7 January 1999. 6. Joseph Weinberg, telephone interview with K. A. Milton, 12 July 1999. 7. Nathan Marcuvitz, telphone interview with K. A. Milton, 27 August 1998. 8. David Saxon, interview with K. A. Milton at UCLA, 29 July 1997. 9. Clarice Schwinger, conversations and interviews with Jagdish Mehra, in Bel Air, California, March 1988. 10. Telephone conversations between Clarice Schwinger and K. A. Milton, 24 April, 9 May, and 15 May 1999. 11. Charles Zemach, telephone interview with K. A. Milton, 22 April 1999. 12. Ian Rosenbloom, telephone interview with K. A. Milton, 4 November 1998. 13. Correspondence and conversations between Walter Dittrich and K. A. Milton, September 1998. 14. Norman Ramsey, interview with K. A. Milton, in Cambridge, Massachusetts, 8 June 1999. 15. Paul Martin, interview with K. A. Milton, in Cambridge, Massachusetts, 8 June 1999. 16. Conversation between Diane Anthony and K. A. Milton, 16 March 1998. 17. J. David Jackson, email letter to K. A. Milton, 30 April 1999. (p. 624 ) 18. Julian Schwinger: the physicist, the teacher, and the man (ed. Y. J. Ng). World Scientific, Singapore, 1996, pp. 150–153. 19. Preface to Particles, sources, and fields , Vol. 2. Addison-Wesley, Reading, MA, 1973 . 20. Kazuhiko Nishijima, letter to K. A. Milton, 30 December 1998. 21. Clarice Schwinger, letter to Jagdish Mehra. 22. Colloque International sur l’Histoire de la Physique des Particules , Paris, 21–23 July 1982. Proceedings published by Les Editions de Physique, Les Ulis, December 1982; first presented at the Fermilab Symposium on The birth of particle physics (eds. L. Brown, and L. Hoddeson). Cambridge University Press, Cambridge, 1983. 23. Sergio Ferrara, telephone interview with K. A. Milton, 17 June 1999. 24. Sheldon Glashow, interview with K. A. Milton, in Cambridge, Massachusetts, 10 June 1999. 25. Jane Wilson, letter to K. A. Milton, 30 August 1998. 26. Beth Purcell, interview with K. A. Milton, in Cambridge, Massachusetts, 9 June 1999. 27. Bert and Ruth Malenka, interview with K. A. Milton, in Belmont, Massachusetts, 11 June 1999. 28. Margaret Kivelson, interview with K. A. Milton at UCLA, 1 August 1997. 29. From a promotional brochure by V. Sattui Winery. 30. Darryl Sattui, telephone message to K. A. Milton, 27 April 1999. 31. Darryl Sattui, letter to Jagdish Mehra, 6 April 1999. 32. Robert Raphael, email letter to K. A. Milton, 9 April 1999. 33. Larry Horwitz, email letter to K. A. Milton, 14 April 1999. 34. Hiroshi Yamauchi, telephone interview with K. A. Milton, 23 June 1999. 35. Robert Warnock, telephone interview with K. A. Milton, 5 May 1999. 36. Abraham Klein, telephone interview with K. A. Milton, 11 December 1998. 37. Abraham Klein, ‘Recollections of Julian Schwinger’ in , p. 1. 38. P. A. M. Dirac, Proc. Roy Soc . ( London ) A 167, 148 (1938). 39. Julian Schwinger Papers (Collection 371), Department of Special Collections, University Research Library, University of California, Los Angeles. 40. Bryce DeWitt, telephone interview with K. A. Milton, 19 April 1999. 41. Richard Arnowitt, interview with K. A. 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Alain Phares, email letter to K. A. Milton, 6 April 1999. 54. M. Jacob and G. C. Wick, Ann. Phys . (N.Y.) 7, 404 (1959). 55. K. T. Mahanthappa, telephone interview with K. A. Milton, 22 February 1998. 56. K. T. Mahanthappa, email letter to K. A. Milton, 22 February 1988. 57. Roger Lazarus, telephone interview with K. A. Milton, 18 June 1999. 58. Yee Jack Ng, email letter to K. A. Milton, 5 May 1999. 59. Sheldon Glashow, in . 60. Roy Glauber, interview with K. A. Milton, in Cambridge, Massachusetts, 8 June 1999. 61. J. M. Blatt and V. F. Weisskopf, Theoretical Nuclear Physics . Wiley, New York, 1952. 62. Fritz Rohrlich, telephone interview with K. A. Milton, 7 April 1999. 63. Yong-Peng Ed Yao, telephone interview with K. A. Milton, 8 April 1999. 64. Tung-Mow Yan, email letter to K. A. Milton, 21 August 1997. 65. Quoted by Michael Lieber in interview with K. A. Milton, 8 April 1999. 66. Conversations between Alice Baños and K. A. Milton, July 1997. 67. 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Phys . 4 , 287, 496 (1949). (p. 626 ) 84. S. Tomonaga, Quantum mechanics . . 85. Jagdish Mehra, The beat of a different drum: the life and science of Richard Feynman. Oxford, Clarendon Press, 1994. 86. Richard Feynman, conversations and interviews with Jagdish Mehra in Pasadena, California, January 1988. 87. Physics Today , February 1989. 88. 88. A. D. Fokker, Z. Phys . 58 , 386 (1929); Physica 9 , 33 (1929). 89. P. A. M. Dirac, Phys. Zeit. Sowjetunion 3 , 64 (1933). 90. R. P. Feynman, Phys. Rev . 76 , 749, 769 (1949). 91. Margaret Newmark, telephone interview with K. A. Milton, 28 June 1999. 92. S. S. Schweber, QED and the men who made it: Dyson, Feynman, Schwinger, and Tomonaga . Princeton University Press, Princeton, 1994, pp. 355–365. 93. Roman Jackiw, interview with K. A. Milton, in Cambridge, Massachusetts, 10 June 1999. 94. Barbara Grizzell (Harold Schwinger’s daughter), interview with K. A. Milton, in Reading, Massachusetts, 10 June 1999. 95. Seth Putterman, conversation with K. A. Milton at UCLA, 28 July 1997. 96. Clarice Schwinger, talk given at Columbia University, 1995. Notes: ( * ) He did sign some. For example, in a two-month period in 1975 he signed three petitions: one for Andrei Sakharov to receive the Nobel Peace Prize, one against astrology, and a third against the rapid growth of nuclear power. 2 ( * ) Schwinger and Teller had been good friends until that episode, but Julian preferred not to speak to Teller afterwards, although when he encountered him at meetings he was invariably polite. ( * ) David Jackson has an unusual memory of that Canadian meeting. ‘In 1957 Julian, Eugene Wigner, Phil Morrison, and I, and others lectured at a Canadian Summer School in Edmonton, Alberta. The Canadian hosts were startled by Clarice’s insistence that a double bed be installed in the office temporarily assigned to Julian—he just could not work without the bed!’ 17 The remarkable encounter with Marshall Baker at Lake Morraine was described in Chapter 12 . ( † ) However, that summer was very productive from Julian’s point of view, as we recall from Chapter 9 . It also included Glashow’s thesis defense, as described in Chapter 12 . ( * ) Clarice offered a reinterpretation of the demonstration Julian offered Brown and Mrs Teller described by Brown. Mrs Teller remarked that for the money, one would think an automatic transmission would be included. Julian was dumbfounded because he considered her remark gauche, having recently given up a Cadillac with automatic everything to purchase this sports car, and he did not know what to say. 10 ( † ) The Schwingers first visited Trieste in 1962, and again in 1965, when they went on to the Feldafing meeting in Austria. ( ‡ ) In June and July 1968, Abdus Salam organized a six-week international symposium on Contemporary Physics to celebrate the official opening of the new buildings of the International Centre for Theoretical Physics in Miramare, near Trieste, Italy. Distinguished physicists from all over the world attended by invitation, including Julian Schwinger, who was one of the stars at the symposium. Prince Raimondo della Torre e Tasso invited all the Nobel laureates to stay as his guests at the Duino Castle; everyone accepted but Paul Dirac, who stayed at the Adriatico Palace Hotel. On one occasion during this symposium, Schwinger asked Jagdish Mehra, ‘As a historian of physics, who do you think had the greatest sense of the architecture of physics?’ Mehra replied, ‘William Rowan Hamilton.’ Schwinger said, ‘I entirely agree. I have always been conscious of the affinity with Hamilton in my own work.’ During his stay with Clarice in Trieste, Schwinger became very fond of Northern Italian cuisine. ( § ) They had visited Japan briefly in 1966 when Julian attended a conference. Julian first had a chance to talk to Tomonaga on that trip. (Recall that because of an accident during the celebration following the announcement of the Nobel Prize, Tomonaga had been unable to attend the Nobel Prize ceremony in 1965.) Some details of that trip are given in Chapter 13 . ( * ) Nishijima had first met the Schwingers at Trieste, and then at the Feldafing meeting in Austria, in the summer of 1965. 20 ( * ) Frances Apt wrote: ‘We were all at a New Year’s Eve Party at Martin’s house, on Stone Road. As a sign of goodwill, one of Charlie’s friends at Arthur D. Little, presented Charlie with a large bottle of excellent Irish whiskey that was not yet marketed in this country. We decided to bring it to the New Year’s Eve festivities, and I made a label for it. I pasted on the side a large piece of paper on which I’d drawn a gaudy border of shamrocks. Then I wrote, in large letters, GAELIC DEW, and down at the bottom I wrote,“ Bottled in the year of the martyrdom of Sir Roger Casement.” It was all in fun, though Charlie suspected that not many people would get it. ‘No one, in fact, did. Paul passed it around when we came in, but people just smiled. Then he put it on the living-room mantlepiece. When you and Julian came in, Julian walked over to it as I nodded. He read it and then came over to me and said, “1916, right?” Of course, it was! And then, very quietly, he told those standing around us who Sir Roger Casement was—and at last they caught on. Now, I admit, not much of a joke, really. But it seemed to me, at the moment it came to mind, a harmless way to show the true Irishness of the contents…’ (Frances Apt to Clarice Schwinger, 20 November 1995; Julian had died on 16 July 1994.) ( * ) Ira Michael Heyman was actually Chancellor of the Berkeley campus, 1980–90. ( * ) On 22 March 1988, when his taped interviews with Julian and Clarice Schwinger were over, Julian presented Jagdish Mehra with a bottle of Cabernet Sauvignon ‘from my vineyard.’ It was indeed an honor to be presented with a bottle, for he gave them only. to a few close friends. It is noteworthy that after his death Sattui Winery made a special edition label with a portrait of Schwinger at the top. ( * ) An example is provided by a paper he wrote with Herman Feshbach in 1949, but only published in 1951, ‘On a phenomenological neutron–proton interaction’ , in which the calculations were ‘done on the Harvard Mark I calculator.’ ( * ) Another student, Hiroshi Yamauchi, once got so annoyed with Schwinger’s perpetual tardiness that he actually arrived after Schwinger did—Schwinger looked surprised. 34 ( * ) By the fall of 1947, Schwinger had gauged the students’ level more accurately. Abe Klein noted that, rather than consisting of research-level problems, the final exam for his first course on quantum mechanics was ‘more than doable.’ 36 It may also have been this later semester that Schwinger taught Applied Science 33, on waveguide theory, the final examination of which is interesting but quite straightforward. Actually, the final exam of the course that DeWitt refers to seems to have been entirely reasonable. 39 ( * ) Charles Sommerfield, who received his degree from Schwinger in 1957, stayed on for two years subsequently as his assistant. His only duty in the position was to join Schwinger for lunch on Wednesdays, after Schwinger’s lecture and before his office hours. He recalled sometimes waiting a considerable time before his boss was ready to leave for lunch, which meant that on occasion the two of them ate alone. Invariably, in those days, the luncheon spot was Chez Dreyfus , and Schwinger would always, after studying the menu carefully, order the same steak. Once Sidney Coleman joined them for lunch, and aware of Schwinger’s habit, ordered first: ‘I’ll have the luncheon steak and the gentleman on my left will have the same.’ Schwinger bristled at being pigeonholed: ‘The gentleman on his left will not have the same,’ and he for once ordered something completely different. ( * ) Many years later Aronson was rebuffed by Schwinger. After the 1978 birthday celebration at UCLA Aronson tried to talk to Schwinger. His response was, ‘What do you want to talk about?’ After that ‘I didn’t bother to go to the 70th.’ 50 Ruth Malenka later told Aronson, ‘You know, he didn’t really mean anything by it, he just did not know how to deal with people.’ 50 ( * ) Glauber had the opinion that most of the thesis topics that Schwinger assigned were ‘ill-conceived and muddy. Virtually none of them were well articulated.’ 60 While it is true that a number of the theses did not reach a significant conclusion, it seems to us that this harsh assessment misses the mark. These were real, and usually difficult, research problems, and most problems often do not yield a solution when they are first enunciated. Schwinger’s philosophy was not to help the student solve his problem, but to provide inspiration, just enough help to get the student to solve the problem on his own. That some students wanted more help cannot be denied, nor that the thesis would have been better if Schwinger had pitched in. But it seems the outstanding results of the caliber of his students justified his technique, even though it could not be emulated by future generations. ( * ) One time after Julian gave a lecture at the Institute for Advanced Study he was so concerned with Oppenheimer’s reaction that afterwards he asked Richard Arnowitt how it went. 41 ( † ) Rohrlich was already ‘a little annoyed’ with Schwinger. Part of his thesis was involved with the scattering of particles possessing quadrupole moments. Schwinger used Rohrlich’s results in his lectures at Harvard on nuclear physics, with due attribution; but John Blatt was in the audience taking notes. Those notes eventually became the famous ‘Blatt and Weisskopf’ book on nuclear physics 61 ; there the reference to Rohrlich’s contribution was ‘unclear.’ 62 ( ‡ ) A similar delay was encountered by Eugen Merzbacher—only by calling Clarice who put him through to Julian was he able to get Julian to call Oppenheimer. ‘Clarice was always helpful in getting jobs for students.’ 51 ( * ) This changed somewhat after the Schwingers decamped for the West Coast. Ng recalled that he was invited the the Schwingers’ parties three times, and they came to the Ngs’ barbeques on two occasions. 18 This change probably reflected the drastic reduction in the number of Schwinger’s students. ( † ) This was the last of many offers. Saxon was very desirous of getting Schwinger to come to UCLA, and tried to persuade him many times to do so, starting in 1947. ( * ) At first Schwinger attended committee meetings, unlike his habit at Harvard, but when he found that his advice was not heeded he stopped attending. ( † ) Schwinger lamented, ‘At Harvard the brightest students used to come to work with me. Here at UCLA, even my name does not attract them; they all want to go to Caltech not UCLA.’ 4 ( * ) Harvard, being a better all around university, probably attracted higher caliber students than did Caltech. ( † ) The Schwingers went to Japan a last time, again a decade later. Nishijima wrote, ‘In December 1990 the Yoshio Nishina Centennial Symposium organized by the Nishina Memorial Foundation was held in Tokyo. Julian was among the invited speakers, and this time he gave a talk on cold fusion . In this visit I had a chance to take them to a tonkatsu restaurant without realizing that it was the last chance to see Julian.’ 20 ( * ) Apparently Feynman then remarked that he also had a covariant formulation. Schwinger later insisted, however, that at the time of the January 1948 APS meeting Feynman had done neither the Lamb shift nor the magnetic moment calculation; only months later, at the Pocono meeting, when Feynman congratulated Schwinger on ‘getting it right,’ had Feynman completed the latter calculation. 4 ( * ) For a detailed account of Feynman’s long struggle, see . ( † ) The symposium was actually held in honor of Julian Schwinger’s 70th birthday. However, at the opening ceremony, he most graciously dedicated it as the ‘Feynman Memorial Symposium.’ This generous gesture was greatly appreciated by all those present. ( ‡ ) In the last week of January 1988, shortly before his death, Richard Feynman told Jagdish Mehra that he wanted to see and interact with Schwinger as much as possible, ‘but here we are, within ten miles of each other, and in spite of numerous overtures by me, we don’t meet. It has been a source of much regret to me.’ 86 It was Schwinger’s extreme shyness and difficulty in reaching out to people that kept him apart from even Feynman. ( * ) Merzbacher recalled that he wondered whether it was worthwhile inviting Schwinger to speak at the Feynman memorial session in San Francisco. He called Clarice, who said she’d call back. ‘To my amazement, he wanted to do it.’ 51 ( † ) In this connection, Margaret Newmark, daughter of Rabi, offered two vignettes of Schwinger. One was about 1953 when she was in college, when she was invited by Clarice to join them for ice cream at Schrafts in Harvard Square. While she and Clarice conversed, Julian was silent and barely looked at her, like a child being brought along by his mother. Twenty-five years later, on the other hand, at Rabi’s 80th birthday celebration (Rabi was born on 29 July 1898), where Schwinger gave his famous talk at the School of International Affairs at Columbia, he appeared as very well tailored and elegant, delivering an elegant paper. He looked like an English diplomat. Afterwards he was warm and outgoing. So different were his private and public persona. 91 ( * ) Wolfgang Pauli, a physicist whom Schwinger greatly admired, even though they had several confrontations, also died of pancreatic cancer on 15 December 1958. His early death caused Schwinger to lose weight and take better care of his health and fitness. More relevant to Schwinger’s death was the fact that his father and brother apparently both also died of pancreatic cancer. 94 ( * ) Also given at Nottingham, and read by Dyson, was Schwinger’s acceptance speech. There he referred again to the threats to science, again recalling the destructive self-isolation of the Chinese government in the 15th century. He also recounted his then recent success in teaching basic quantum mechanics to high school students. In remarks that fly in the face of Schwinger’s presumed elitism, he said, ‘They understood it, they loved it. And I used no more than a bit of algebra, a bit of geometry. So: catch them young; educate them properly; and there are no mysteries, no priests. It all comes down to a properly educated public.’ 18 原文见 http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780198527459.001.0001/acprof-9780198527459-chapter-16
@ARTICLE{GXFF12, author = {Shan Gao and Shuo Xu and Yaping Fang and Jianwen Fang}, title = {Using Multitask Classification Methods to Investigate the Kinase-Specific Phosphorylation Sites}, journal = {Proteome Science}, year = {2012}, volume = {10}, pages = {S7}, number = {Suppl. 1}, abstract = {\textbf{Background:} Identification of phosphorylation sites by computational methods is becoming increasingly important because it reduces labor-intensive and costly experiments and can improve our understanding of the common properties and underlying mechanisms of protein phosphorylation. \textbf{Methods:} A multitask learning framework for learning four kinase families simultaneously, instead of studying each kinase family of phosphorylation sites separately, is presented in the study. The framework includes two multitask classification methods: the Multi-Task Least Squares Support Vector Machines (MTLS-SVMs) and the Multi-Task Feature Selection (MT-Feat3). \textbf{Results:} Using the multitask learning framework, we successfully identify 18 common features shared by four kinase families of phosphorylation sites. The reliability of selected features is demonstrated by the consistent performance in two multi-task learning methods. \textbf{Conclusions:} The selected features can be used to build efficient multitask classifiers with good performance, suggesting they are important to protein phosphorylation across 4 kinase families.}, } 全文见： Using multitask classification methods to investigate the kinase-specific phosph.pdf
就是这个会议有点晚。 Dear Yuxian Liu, On behalf of the Organization Committee of the International Conference on Innovative Methods for Innovation Management and Policy (IM2012), I am pleased to inform you that your abstract has been accepted. ID: IM013005957 Title: ... Congratulations and welcome to IM2012, which will be held in Beijing, May 21-24, 2012. (See the attachment for more information). We kindly ask you to: - Register for the conference to ensure your participation and pay the registration fee as soon as possible; - Inform your co-authors, as only first author will receive this notification; - Confirm that you will submit the extended abstract before April 10, and please use your paper ID and E-mail address: ... when you submit the extended abstract; - If you submit a full paper (not required), we would also like you to prepare PowerPoint slides and give a presentation. If you are submitting a full paper (or poster – as you have chosen when submitting your abstract), please do so before April 10. Templates can be downloaded from http://www.aaaa.org.cn/im2012/paper.php/ . - Please prepare your full paper ( if you have) to ensure it can be published. For further information on conference registration, hotels, and other questions, see http://www.aaaa.org.cn/im2012/ or email: imconference@bit.edu.cn . We sincerely hope that you will join us in making our conference a success. We look forward to welcoming you to China and to IM2012. Best regards Yours sincerely, ...... Conference Chair
Ralph M. Steinman，1943年出生于加拿大蒙特利尔。在麦吉尔大学学习生物学和化学。1968年从哈佛医学院获得医学博士学位。自1970年开始他一直在洛克菲勒大学工作，1988年开始成为免疫学教授，并担任免疫学和免疫疾病中心主任。 学术论著 Dendritic cells and the control of immunity. from ukpmc.ac.uk …, RM Steinman - Nature, 1998 - ukpmc.ac.uk UK PubMed Central (UKPMC) is an archive of life sciences journal literature. Cited by 9385 - Related articles - Cached - BL Direct - All 26 versions The dendritic cell system and its role in immunogenicity from rockefeller.edu RM Steinman - Annual review of immunology, 1991 - annualreviews.org Abstract Dendritic cells are a system of antigen presenting cells that function to initiate several immune responses such as the sensitization ofMHC-restric ted T cells, the rejection of organ transplants, and the formation of T dependent antibodies. Dendritic cells are found in ... Cited by 3704 - Related articles - All 10 versions Generation of large numbers of dendritic cells from mouse bone marrow cultures supplemented with granulocyte/macrophage colony-stimulating factor. from rupress.org …, S Ikehara, S Muramatsu, RM Steinman - The Journal of …, 1992 - jem.rupress.org Summary Antigen-presenting, major histocompatibility complex (MHC) class II-rich dendritic cells are known to arise from bone marrow. However, marrow lacks mature dendritic cells, and substantial numbers of proliferating less-mature cells have yet to be identified. The ... Cited by 2502 - Related articles - BL Direct - All 6 versions Tolerogenic dendritic cells* from rockefeller.edu RM Steinman , D Hawiger… - Annual review of …, 2003 - annualreviews.org ▪ Abstract Dendritic cells (DCs) have several functions in innate and adaptive immunity. In addition, there is increasing evidence that DCs in situ induce antigen-specific unresponsiveness or tolerance in central lymphoid organs and in the periphery. In the ... Cited by 1693 - Related articles - BL Direct - All 7 versions Proliferating dendritic cell progenitors in human blood. from rupress.org …, PO Fritsch, RM Steinman … - The Journal of …, 1994 - jem.rupress.org Summary CD34 § cells in human cord blood and marrow are known to give rise to dendritic cells (DC), as well as to other myeloid lineages. CD34 § cells are rare in adult blood, however, making it difficult to use CD34 + ceils to ascertain if DC progenitors are present in the circulation ... Cited by 1499 - Related articles - BL Direct - All 6 versions Antigen-specific inhibition of effector T cell function in humans after injection of immature dendritic cells from rupress.org MV Dhodapkar, RM Steinman … - The Journal of …, 2001 - jem.rupress.org Immunostimulatory properties of dendritic cells (DCs) are linked to their maturation state. Injection of mature DCs rapidly enhances antigen-specific CD4 + and CD8 + T cell immunity in humans. Here we describe the immune response to a single injection of immature DCs ... Cited by 1090 - Related articles - BL Direct - All 8 versions Dendritic cells: specialized and regulated antigen processing machines. …, RM Steinman - Cell, 2001 - jbioleng.org 1. Cell. 2001 Aug 10;106(3):255-8. Dendritic cells: specialized and regulated antigen processing machines. Mellman I, Steinman RM . Department of Cell Biology, Ludwig Institute for Cancer Research, Yale University School of Medicine, New Haven, CT 06520, USA. ... Cited by 1279 - Related articles - All 5 versions Dendritic cells induce peripheral T cell unresponsiveness under steady state conditions in vivo from rupress.org …, M Rivera, JV Ravetch, RM Steinman … - The Journal of …, 2001 - jem.rupress.org Dendritic cells (DCs) have the capacity to initiate immune responses, but it has been postulated that they may also be involved in inducing peripheral tolerance. To examine the function of DCs in the steady state we devised an antigen delivery system targeting these specialized ... Cited by 1051 - Related articles - BL Direct - All 11 versions Vaccination with mage-3A1 peptide–pulsed mature, monocyte-derived dendritic cells expands specific cytotoxic T cells and induces regression of some metastases in … from rupress.org …, EB Brcker, RM Steinman … - The Journal of …, 1999 - jem.rupress.org Dendritic cells (DCs) are considered to be promising adjuvants for inducing immunity to cancer. We used mature, monocyte-derived DCs to elicit resistance to malignant melanoma. The DCs were pulsed with Mage-3A1 tumor peptide and a recall antigen, tetanus toxoid ... Cited by 1081 - Related articles - All 6 versions Identification of a novel cell type in peripheral lymphoid organs of mice: I. Morphology, quantitation, tissue distribution from nih.gov RM Steinman … - The Journal of experimental medicine, 1973 - ncbi.nlm.nih.gov During the course of observations on the cells of mouse spleen that adhere to glass and plastic surfaces, it was clear that this population was quite hetero- geneous. In addition to mononuclear phagocytes, granulocytes, and lympho- cytes, we noticed a large stellate cell with distinct ... Cited by 1062 - Related articles - All 7 versions http://scholar.google.com.hk/scholar?hl=enq=RM+Steinman+btnG=Searchas_sdt=0%2C5as_ylo=as_vis=0 北京时间10月3日下午5点30分，2011年诺贝尔生理学或医学奖揭晓，美国、法国三位科学家因在免疫学方面的发现获奖。其中一半的奖金归于 Bruce A. Beutler 和 Jules A. Hoffmann ，获奖理由是“先天免疫激活方面的发现”；另一半奖金归于 Ralph M. Steinman ，获奖理由是“发现树枝状细胞及其在获得性免疫中的作用”。 今年的诺奖得主发现了免疫系统激活的关键原理，从而彻底革新了我们对免疫系统的认识。 免疫应答作为一种能帮助人类与其它动物抵御细菌及其它微生物的生理过程，长久以来，科学家们一直在寻找它的“守护者”。Bruce Beutler和Jules Hoffmann发现了能识别微生物并激活先天性免疫的受体蛋白质，从而揭示了身体免疫应答过程的第一步。Ralph Steinman则发现了免疫系统中的树突状细胞，以及其可激活并控制获得性免疫的功能，从而完成身体免疫应答过程的下一步，即将微生物清除出体内。 三位诺奖得主的发现揭示了免疫应答中的先天性免疫和获得性免疫是如何被激活，从而让我们对疾病机理有了一个新的见解。他们的工作为传染病、癌症以及炎症的防治开辟了新的道路。 加拿大总理哈珀3日发表声明，代表全体加拿大人对加拿大科学家拉尔夫·斯坦曼获得2011年诺贝尔生理学或医学奖表示祝贺，同时对他在3天前因病逝世深表遗憾。
What kind of committee would make such a demand for super short abstracts? I had an abstract of 800 words. (Yes, I know it is too long.) So, I just spent 30 mins to shorten it to less than 160 words. Here it is. ON THE EASTWARD SHIFT OF THE ARABIAN SEA OXYGEN MINIMUM ZONE Observations indicate that the upper part of the Arabian Sea oxygen minimum zone (ASOMZ; above 400 m) appears to the east of most productive regions along the western boundary of the Arabian Sea. There is no consensus about what causes the so-called “eastward shift.” We use a coupled biological/physical model to investigate the processes that determine the “eastward shift.” The physical component of the model is a variable-density, 6 1/2-layer model, with each layer corresponding to a distinct dynamic regime or water-mass type. Its biological component consists of a set of advective-diffusive equations in each layer that determine nitrogen concentration in five compartments, namely, nutrients, phytoplankton, zooplankton, and two size classes of detritus. In addition, the model contains an oxygen compartment that reacts to production and consumption of dissolved inorganic nitrogen in the biological system. We will show the relative roles of physical versus biological processes in generating the so-called “eastward shift” in the upper ASOMZ.
2011 EU-China Workshop on Complexity Science Talk Abstract TAIPEX —An Online ExperimentalPlatform to Study Market Behavior Sai-Ping Li Institute of Physics, Academia Sinica, Taipei 115, Taiwan The TAIPEX , which is one of the existing prediction market platforms in the world, was first set up in early 2004 in Taiwan as an experimental toolto study the voting behavior of the people in Taiwan. After the first successful experimental launchon this platform, it was soon realized that one couldin fact study financial market behaviors by using this platform. In subsequent years, that is, from early 2004 till theend of 2010, eight experiments have been carried out onthis prediction market platform. These include: three presidential elections (2 from Taiwan and one from the US), one parliamentary election, three city mayor elections and one on bird flu. From the results of these experiments, we have observed many stylized facts that are known to exist in everyday financial markets. For example, Figure 1 shows the probability density of normalized price returns of TAIPEX in the 2004 Taiwan parliamentary election with different time lagsequal to 55(red), 148(black), 403(yellow), 1097(green) and 8103(blue) minutes. The figure illustrates two interesting features. The firstfeature is the heavy tails onthe two ends ofthe curves. One can see this easily when compared to a Gaussian distribution as shown in the figure. Heavy tails of price returns in financial markets arestylized facts that are knownto market practitionersfor a long timeand our experiments also exhibitsuch a feature. Another feature that we can observe in this figure is the universality of different time lag curves. One can see that the different time lag curves can indeed be represented by a single distribution curve. We also observe that other well known stylized facts also appear in our prediction mark Figure 1. Probability density of normalized price returns with time lag equal to 55(red), 148(black), 403(yellow), 1097(green) and 8103(blue) minutes. The dashed line was obtained from a Cauchy distribution and the dotted line is a Gaussian distribution of unit variance. Aside from the already well known stylized facts, we have further uncovered many features that are likely to exist but are unable to be detected in financial markets. Take, for example, we can construct a trading network of the traders from the data of the experiment on this prediction market platform . The same kind of networkis unlikely to be constructed due to the lack of data availabilityin real financial markets. Figure 2 is an illustration of a trading network among traders of our experiment on the 2006 Taipei Mayor Election. The network is based on the data from Day 3. The number of traders and the trading network grew sincetherewere more registered players to do trading on the platformas the experiment continueduntil the dayof the election. Figure 2. The trading network on Day 3 of the 2006 Taipei Mayor Election experiment. The network consists of 40 interconnected nodes. isolated nodes are not shown here . In this talk, we will first give abrief introduction of the historical development and the current status ofprediction markets. As an example of how prediction markets work, we will give details of doingtrading on our prediction market platform. Results of our previous experiments will be summarized and presented, including the most recent experiment done by the end of 2010. Possible future work will beproposed and discussed. Most importantly, collaborations on this prediction market platform are welcome. References: http://socioecono.phys.sinica.edu.tw/ K.J. Arrow et.al., Science 320(2008)877-8 G. Tziralis and I. Tatsiopoulos, “Prediction Markets: An Extended Literature Review”, TheJournal of Prediction Markets 1(2007)75-91. S.C. Wang et.al., “Statistical Properties of an Experimental Political Futures Market”, Quantitative Finance 9(2009)9-16. S.C. Wang et.al., “Network Topology of an Experimental Futures Exchange”, European Physical Journal B62(2008)105-111. Piecewise Smooth Lyapunov Function for a Nonlinear Dynamical System Yan Gao Business School, University of Shanghai for Science and Technology, Shanghai 200093, China email:gaoyan@usst.edu.cn In this paper, stability and attraction for a nonlinear dynamical system with nonsmooth Lyapunov function are studied. The previous results on stability and attraction with a max-type Lyapunov function are extended to the case where Lyapunov function is piecewise smooth. A condition, under which stability and attraction is guaranteed with a piecewise smooth Lyapunov function, is proposed. Taking two certain classes of piecewise smooth functions as Lyapunov functions, related conditions for stability and attraction are developed. Key Words. Nonlinear dynamical system, stability, region of attraction, Lyapnov functions, nonsmooth analysis, piecewise smooth function. Hurst Exponents for Short Time Series 短时间序列的分形指数 Jingchao Qi, and Huijie Yang Biz School, University of Shanghai for Science and Technology, A new concept, called balanced estimator of diffusion entropy, is proposed to detect scaling in short time series. The effectiveness of the method is verified by means of a large number of artificial fractional Brownian motions. It is used also to detect scaling properties and structural breaks in stock price series of Shanghai Stock market. PACS ： 05.45.T, 89.75.D, 05.40.F, 05.40 Keyword(s); short time series; scaling; diffusion entropy Global Compact Representation of Continuous Piecewise Linear Functions and Its Application Xin-Ye Li Business School, University of Shanghai for Science and Technology, Shanghai 200093, China Critical point and critical cluster distribution of explosive site percolation in random network Yu-gang Ma 1) and Ding-ding Han 2) 1 Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China 2 School of Information Science and Technology, East China Normal University, Shanghai 2000241, China Recently a new kind of percolation, named explosive percolation was proposed. By introducing a proper competitive mechanism, it was first found by Achlioptas, D'Souza, and Spencer and was subsequently studied intensely by other scientists that the bond percolation in random networks became discontinuous. Such kind of percolation has a delayed transition point but still maintain a power-law critical cluster distribution with yet the exponent different from the classical one, indicating the absence of universality in sense of different percolation strategies. However further numerical and theoretical studies have provided evidences that the bond explosive percolation in random network is actually continuous in the thermodynamics limit except for the global competitive case in which all the links in network participate in the selection. Although the argument still exists, explosive percolation has brought new insights to the percolation theory. However the two most important properties, namely the location of the critical point and the critical cluster distribution have not been studied systematically. Previous studies presented the related results only for their special models, which neither provide any general conclusions nor help to understand the possible universal behavior. In this letter, we focus on this problem instead of just studying the continuity of explosive percolation. By introducing a best-of-m competitive rule the explosive site percolation in ER network is studied. We prove that the critical point tc(m, k) has a nontrivial limitation Tc(k) 1 as m = N →∞. By developing a finite size scaling method, Tc(k) is found to scale asymptotically as . The result is further generalized by for all m with approximated by an arctan function. The critical cluster distribution is found to be power law with exponent about -2.5 regardless of m, leading to a conjecture that the universality remains in sense of different percolation strategy. The continuity of the percolation is also discussed. The present results basically generalize the classical conclusion to adapt to a large class of explosive percolation. Key words: explosive percolation, random network, critical point, critical cluster distribution Fluctuation scaling in complex networks Ding-ding Han School of Information Science and Technology, East China Normal University, Shanghai 200241, China Fluctuation is a universal phenomenon in complex networks. Since L.R.Taylor’s influential paper on natural populations was published in 1961, a scaling relationship has been observed in a wide range of disciplines, ranging from population dynamics through the Internet to the stock market. The original law exhibits that for any fixed species there is a power-law scaling between fluctuations in the size of a population (characterized by standard deviation) and the average population, namely In this paper, brief introduction about fluctuation scaling is given. The fluctuation can be divided into temporal fluctuation scaling and ensemble fluctuation scaling. Besides, we have investigated the evolution of the download network for the rank-ordered papers which were listed in Zhang’s Econophysics web page. From 2004 to 2007, the download distribution shows the change of the exponents even though the rank-ordered distribution still keeps scale-free feature, reflecting the change of traffic on nodes which represent the given downloaded papers. Further, we give a quantitative analysis for the average download rates per day, which shows day-by-day fluctuation. The average flux shows a fast exponential decay as a function of the rank, while the dispersion does not show an obvious dependence of the rank. Interestingly, the dispersion of the download rate distributions shows power-law scaling behavior with its average flux, namely . In different time windows ranging from about 6.5 months to 31 months in which the download distributions are accumulated, the scaling parameter changes with the time windows, namely from 0.60 to 0.89. The origins are qualitatively interpreted by two models. Future work on quantitative model simulation and a possible -scaling of network fluctuation is in progress. Key words: Fluctuation scaling; complex netwrks; random walker model; fluctuation exponent; time window Long division unites - long union divides, A model for cultural evolution J. Jiang, R. Wang, Michel Pezeril, and Q.A. Wang One of the historical phenomena in the time evolution of cultural, national and economic systems is the transition between union and division of one or several entities. In this work, we propose a union-division model based on the maxim "long union divides and long division unites" in order to investigate the long time behaviors of the networks composed of nodes representing the above mentioned entities. Each node is characterized by several quantities such as identity, ingredient, richness, and age. The time evolution of the network is probabilistic depending on the above quantities and on the interaction between the neighboring n nodes. This work offers a long term view on the apparently periodic dynamics of an ensemble of cultural entities. Self-organization and Preconditions of Efficient Markets You-Gui Wang Department of Systems Science, School of Management, Beijing Normal University, Beijing 100875, China, Email: ygwang@bnu.edu.cn Most of economists have devoted themselves into proving the existence of “invisible hand” in marketing systems. Traditional approaches claim that an efficient market lies on three presuppositions: rationality of individual market participants, complete information and equilibrium of the market. These presumptions result from the static postulations of mainstream economics. In this talk, I will show that from dynamic perspective a market can achieve an efficient state without those strong assumptions. The patterns of self-organization of an evolutionary market are displayed where the premises of individual rationality, single price as well as equilibrium are abandoned. Keywords: Market efficiency, Self-organization, Rationality, Market equilibrium, Dynamic structure. Accelerating growth and size-dependent distribution of human online activities Zhang Jiang Department of Systems Science, School of Management, Beijing Normal University, Beijing 100875, China, Research on human online activities usually assumes that total activity T increases linearly with active population P, that is, T ∝ P^γ (γ = 1). However, we find examples of systems where total activity grows faster than active population. Our study shows that the power law relationship T ∝ P^γ (γ 1) is in fact ubiquitous in online activities such as microblogging, news voting, and photo tagging. We call the pattern “accelerating growth” and find it relates to a type of distribution that changes with system size. We show both analytically and empirically how the growth rate γ associates with a scaling parameter b in the size-dependent distribution. As most previous studies explain accelerating growth by power law distribution, the model of size-dependent distribution is worth further exploration. Statistics and Evolution of Donations for 2008 Wenchuan Earthquake Qinghua Chen ( 陈清华 ), Yajing Wu ( 吴亚晶 ), Jinzhong Guo( 郭金忠 ), Yougui Wang( 王有贵 ) Department of Systems Science, School of Management, Beijing Normal University, Beijing 100875, People's Republic of China qinghuachen@bnu.edu.cn (86-10-58802732) Based on the data of individual donations from Chinese Red Cross Foundation , this paper analyzes and discusses the distribution of individual donations and evolutions of some statistical properties over time. The results show: 1) individual donations distribution has shown some power law characters, and some donation numbers are preferred; 2) the growths of person times and total donations obey Logistic growth, and the growth of person times is ahead of another; 3) the trend of average donations amount is that, firstly decreases and then increase, with large donations coming at a subsequent time or stage . This paper proposes a multi-agent model to simulate donations’ evolution based information diffusion. Figure 1. Zipf’s plot of donations Figure 2. Pareto’s plot of donation Figure 3. The growths of donations amount and person times, and the fitting of Logistic curve Figure 4. The daily average of the accumulated donations amount Keywords : individual donations, power law, logistic growth Perspectives of several directions in recent complex system research Bing-Hong Wang Department of Modern Physics, University of Science and Technology of China Hefei, 230026, China and The Research Center for Complex Systems, University of Shanghai for Science and Technology, Shanghai, 200093, China bhwang@ustc.edu.cn Study of the evolutionary games on complex networks We study the evolutionary games on complex networks, including the prisoner's dilemma game and the public goods game. Our research focus is how the clustering structure, social diversity and aspiration-induced migration affect the cooperative behavior. We find that the higher clustering coefficient enhances the cooperation in spatial public goods game. Due to the existence of social diversity, the influence of different individuals is different. The influence of an individual is defined as the power of its degree, where the power exponent is an adjustable parameter. During the evolutionary process, every individual chooses one of its neighbors as a reference with a probability proportional to the influence of the neighbor. It is found that for the fixed value of the temptation to defect, there exists an optimal value of , leading to the highest level of cooperation. We propose an aspiration-induced migration in which individuals will migrate to new sites provided that their payoffs are below some aspiration level. It is found that moderate aspiration level can best favor cooperative behavior. Cooperation percolation in spatial evolutionary games is specially considered. We study the dynamical organization of cooperator clusters in prisoner’s dilemma game on regular and complex networks. It has been found that when the initial concentration of cooperators in the systems exceeds a threshold, there is a phase transition characterized by the emergence of a giant spanning cooperative cluster of the order of network size. Depending on the network structure and the temptation to defect, the phase transition appears to belong to different universality classes of percolation, including regular percolation, invasion percolation and other unreported classes. Transportation Dynamics on Mobile Node Network Most existing works on transportation dynamics focus on the networks of a fixed structure, but networks whose nodes are mobile have become widespread, such as cell-phone networks. We introduce a model to explore the basic physics of transportation on mobile networks. Of particular interest are the dependence of the throughput on speed of agent movement and communication range. Our computations reveal a hierarchical dependence for the former, while for the latter we find an algebraic power law between the throughput and the communication range with an exponent determined by the speed. We develop a physical theory based on the Fokker-Planck equation to explain these phenomena. Our findings provide insights into complex transportation dynamics arising commonly in natural and engineering systems. Reference: Phys.Rev.E 83.016102(2011) Newsbag, an adaptive model for news recommendation Dott. Giulio Cimini Uni Fribourg and Univ. Rome, Italy We propose an adaptive recommendation model which combines similarities in users' rating patterns with epidemic-like spreading of news on an evolving social network. Our system has high filtering efficiency and robustness against malicious behavior, and outperforms other widely adopted recommendation methods. The model also sheds light on who people do follow in social communities and where they do search for good information sources. Agenetic perspective on citation networks Dott. Stanislao Gualdi Uni Fribourg and Univ. Rome, Italy we develop an analytical framework to asses genetic relations between papers. We show that such framework can be used both to highlight papers which play a fundamental role in the development of a research field both to build a recommender system which filters relevant literature for a given interest. The spectral analysis for biology networks Jiao Gu （ 辜姣） Central China Normal University ， Wuhan ， P.R.China We constructed the protein network and domain networks from the database. Baced on the analysis ofspectrumof normalized Laplacian matrix, we could classify the networks and find phylogenetic information from these networks. Statistical Mechanics of Social Tagging Networks: Structure, Dynamics and Function Zike Zhang （张子柯） University of Fribourg, Switzerland In this talk, I would introduce our recent progress on the study of social tagging netowks, including the structure of how to describe and measure it, the dynamics of how it evolves and it application in recommender systems. It is expected to give a general picture of Social Tagging Networks and possible research topics, as well as challenges. Potentials of sino-european cooperations in complexity sciences Jian-Wei Zhang University of Hamburg ， Hamburg ， German European and China cooperation opportunities in Complexity Sciences Jeff Johnson Open University, London, UK Complexity of systems with respect to the economy and society Dr. Fred von Gunten International Strategy and Competition University of Fribourg ， Switzerland “Complexity research as an interdisciplinary undertaking is concerned with the question how orders, structures, chaos and break downs can be created by the relationships of many elements of a complex system… The object of complexity research is to identify and understand chaos, tensions and conflicts in complex systems (molecules in materials, cellules in organisms or human beings in markets and organisations) so as to acquire new knowledge for the potential of establishing new orders.” Mainzer, 2008, Komplexitt, p. 10). When this definition is applied to the economy and society then a number of difficulties have to be overcome. In this contribution one attempts to explain how three basic propositions contribute to improving the situation. First, market or state capitalism must be identified as organised socio-economic systems. Second, these systems must be presented as three level economies instead of only two level economies. Third, in the end, “pure analysis” in the economic and social sciences must be integrated with the other sub-systems of the nation-state, at the international level with international organisations. That way the degree of complexity of systems with respect to the economy and society can be positively influenced
研究人员从水稻籼稻品种93-11中克隆并鉴定了控制水稻籼粳分类的基因并将其命名为PHR1。转基因功能互补实验证明PHR1是区分水稻籼粳分类的基因。在水稻中抑制或过量表达PHR1，得到具不同抗病虫害能力的转基因水稻，表明可以利用基因工程技术调控该基因从而调节植物抗性。 Yanchun Yu,Tian Tang, Qian Qian, YonghongWang,Meixian Yan,Dali Zeng, Bin Han, Chung-IWu,Suhua Shi, and Jiayang Lia,Independent Losses of Function in a Polyphenol Oxidase in Rice: Differentiation in Grain Discoloration between Subspecies and the Role of Positive Selection under Domestication.The Plant Cell, 2008.Vol. 20: 2946–2959, Phenol reaction phenotype（PHR）表现在籼稻中，而在粳稻中缺失，籼稻和粳稻在收获时通常都是金黄色，因此籼稻经过phenol处理会变成褐色或者在储存的过程中会变身；粳稻则不会变色。并且PHR是由单个gene控制，phr1 gene是引起PHR的原因。paper中phr1 gene的clone过程如下： 1、初步定位：应用PHR-positive indica cv MH63 和PHR-negative japonica cv CJ06 构建一个非常大的作图群体，杂交得到5589个F2群体（分离比3:1；PHR-positive4203：PHR-negative 1386）。前期研究phr1定位在4号染色体，应用新的PCR-based marker S100与S115在水稻遗传图谱phr1的两端。然后应用这两个标记扫描所有的PHR-negative 植株。phr1 gene定位到S100和S115之间，遗传距离9.3cM 与8.5cM之间。 2、精细定位：获得66个phr1与S100之间的重组个体以及40个phr1与S115之间的重组个体。
How to write abstract and introduction for a paper/conference paper: The abstract of a paper or a conference paper is normally one paragraph with 100-400 words. It is normally structured into several sentences. Each sentence should be able to answer the following questions: 1. what is this paper about- a general problem statement 2. Why is this important- what is the significance. This, on the other hand, explains why you conducted the research 3. What has been done before: state-of-the-art. 4. what is the shortcoming in what has been done before, why that is not good 5. What you have done in this research? 6. how that (what you have achieved) improved related to the state-of-the-art Following the above six points, and in this logical order, you should be able to present a very excellent abstract As for the title of the paper: The title of a paper should not be too long, and should not be too specific. it normally has 7 words, (not counting 'of', 'the','a',etc) How to write an introduction: An introduction is an extended version of an abstract, so it should be formulated the same way as the abstract. Instead of stating each of the above-mentioned questions in one or two sentences, an introduction should be able to give more detailed information and provide a profound discussion. For an 8 pages conference paper, the introduction part is normally one page long with 4 paragraphs. to put the answers to the above 6 questions into 4 paragraphs, you need to: v in the first paragraph: what is this paper about general problem background introduction why is this important-this states the significance of you research v in the second paragraph: What has been done before- state-of-the-art. why that is not good enough, the shortcoming The second paragraph in the introduction is actually the literature review. As for how to write a good literature review, I need to learn further more and then come up with some good 'how to', and this part can be in one paragraph or if too much information, then 2 Normally, a paragraph in a formal paper is around 10 lines in a single column A4 paper. A sentence, starting from one full stop until the following next full stop is no longer than 4 lines. you can always use comma ',' to break the sentence (as to where to put the comma, you follow your own feeling when read through it, normally, a adverb clause, phrase, etc), so that readers or reviewers could have a (puff) rest when they find difficulty in absorbing the too-much information in the long sentence. two-line is the normal length, but on the other hand, do not keep all the sentences in two-line length, try to use long and short sentences alternatively (this is not the right word, I am afraid) and use various sentence structures. v in the third paragraph: based on the literature review in the second paragraph, identify the research question, and state what you have done in this study what you have found (your result, contributions what is good about your work) and how that improves/ relates to the current start-of-the-art v In the fourth paragraph: state the organisation/ strucuture of the paper/ framework/outline/or whatever you name it, such as: the reminder of this paper is organised as follows: How to write a conclusion: Most of the time, you will see people put conclusions all in one single paragraph. It is suggested that emphasize each aspect in separated paragraphs or using bulleted list. In conclusion, you do not need to state the general problem again, you can start with a introduction of what you have done in this research, and then use bulleted dots to present the significance of your research, its contributions to the practical problem, the advantages of the proposed method, the superior performance of the model, etc. Start a new paragraph stating the future work or further study. Research never stops at wherever you achieved. Further work shows the continuing work and also the significance of your study, otherwise, there is no point if you will stop doing this topic after this paper. What else can be done to further improve or can this method be applied somewhere else. This should be the final paragraph of the entire paper and it is suggested that you conclude with very strong point, so that the readers or the reviewers finish reading with very good impression. Another point worth mentioning is that always use up the full page limit for a conference, put as much information as you can as long as you can keep the consistence and the cohesion. Keep your paper as a logic story.
what's the difference between abstract and introduction? This afternoon, one of my students asked me a question about the graduate theses: what's the difference between abstract and introduction? It's a common and complex question for the beginners, esp. for the undergraduates. Here, wecan find some suggestions for this question: At first glance, it might seem that the introduction and the abstract are very similar because they both present the research problem and objectives as well as briefly reviewing methodology, main findings and main conclusions. However, there are important differences between the two: Introduction: an introduction leads the reader into the subject of study by giving the state of art of knowledge in the area, the lacunae, and reasons for undertaking the present study. it should be short, but does not have a word limit; Main purpose is to introduce the research by presenting its context or background. Introductions usually go from general to specific, introducing the research problem and how it will be investigated. Abstract: An abstract is a sort of summary of the entire paper. It should be specific about the main findings and not vague. It will also specify what was the aims and goals of the study. so, It has a maximum word limit; It is a summary of the whole research; Its main purpose is to summarize the research--particularly the objective and the main finding/conclusion, Not to introduce the research area.
标签: abstract
