In December 2015, I was invited by Mr. Yang Zhenning to give a lecture at the Institute for Advanced Study of Tsinghua University. During this period, he had two long talks with Mr. Yang. After the e-mail communication, the two sides felt the need to do some in-depth exchanges on some issues again. On the morning of May 6, 2016, the author visited Mr. Yang again and asked him for advice and verification on some issues. This part of the dialogue recording is relatively clear, but the text has not been published since it was sorted out. On the occasion of Mr. Yang's 100th birthday, I would like to dedicate this article to readers, which will help to fully understand the inner world of Mr. Yang Zhenning.
Written by | Hou Yude (Institute of History of Science and Technology, Shanxi University)
Source | This article is from Physics, No. 9, 2021
Photographed at the home of Mr. Yang Zhenning on May 6, 2016
Hou Yude: Hello Mr. Yang! It's a pleasure to see you again! It feels like you're looking a lot better than you were last December.
Yang Zhenning: Older people are naturally afraid of cold, and in the summer, the weather is warmer, and the body will feel much more comfortable than in winter.
Hou Yude: Then I will get to the point. The first topic I'm going to ask you about today is related to when I came to see you last December. At that time, under your arrangement, I gave a lecture at the Tsinghua Institute for Advanced Study, and you were unable to attend in person because of the incident. After the report, one of the issues we discussed together (Academician Zhu Bangfen, Professor Qin Kecheng, Professor Ge Weikun, Professor Lou Yuqing, etc.) was the topic of scientists and politics. Scientists can be broadly divided into two categories, such as Max Born and Enrico Fermi, who are more willing to do scientific research and teaching work than to directly devote themselves to social management related to politics; others are better at or even enthusiastic about such things, such as Robert Oppenheimer, Edward Teller and Fredrick Lindemann, Churchill's adviser) and others. One person involved in this topic was von Neumann, who was a colleague of you at Princeton, right?
Yang Zhenning: Yes, von Neumann is my colleague at Princeton, and he is more than a decade older than me.
Hou Yude: In a biography of von Neumann, the biographer said that von Neumann had an extreme point of view, that he not only participated in social and political affairs, but also actively suggested that the United States should engage in nuclear deterrence during the Cold War and called for a pre-decisive strike. In my opinion, this is an extreme idea that is almost crazy. The book says that the philosopher and mathematician Bertrand Russell was the main driver of the pre-emptive war, while von Neumann was more assertive and keen to surprise the nuclear weapon to strike first.1 Is the von Neumann you see really so extreme and aggressive?
Yang Zhenning: Some of what you said is true, but your explanation may not be quite correct. For example, the views of von Neumann and Taylor in politics did not start like this, but slowly evolved into this. This evolution is closely related to the development of the world situation as a whole. Your explanation divides people into two categories, the actual people are not divided into two categories, and between the two extremes, the distribution of people is continuous. In addition, a person's position in politics is changing at any time. I think so, some people do their own research, regardless of other things; some people do other things other than their own research. The nature of these two different kinds of people is obvious, and this phenomenon has existed in ancient and modern China and abroad. Oppenheimer was a very intelligent physicist when he was young, but he was also very interested in what was happening in the world, so he participated in many leftist organizations in the United States in the 1930s. But that doesn't mean he's going to be involved in politics at this point, he just thinks it's something a modern person should do. Fermi, on the other hand, is not uninterested in these things, but he does not participate in this organization, that organization. In retrospect, Chinese is the same, some Chinese physicists like to express their opinions on politics, and some do not. When the whole world situation changes, it also affects the direction of everyone's development. Oppenheimer, for example, had close ties to many left-leaning organizations in the 1930s, and later the U.S. government selected him as an important leader for the atomic bomb. So you could also say that this pushed the fate of his life from the direction of mainly doing physics to another direction. After this change, his personal strengths were brought to play, but in the end it also brought him a blow. So what I want to talk about is that you can't fix this person in advance that this person is this faction and that person is that faction, and he changes with time and circumstances. Another example is Taylor, he is my mentor, when he was my teacher, he mainly did physics research, but for special reasons, Oppenheimer let him study and build hydrogen bombs, thus changing the trajectory of his life. Oppenheimer's involvement in Taylor's study of the hydrogen bomb was more fortuitous. Oppenheimer's real purpose was not because he felt that hydrogen bomb research was really necessary at the time, the opposite was true. Oppenheimer summoned many physicists to study the atomic bomb, of which Taylor was one of them, and they were about the same age and had a good relationship at the time. There was a theory group in the Manhattan Project, and the two very important people in it were Hans Bethe and Taylor, and Bet was the team leader (thick: he later won the Nobel Prize). Yes, Bate is famous for his 3 long articles in the 1930s2), published in the Reviews of Modern Physics. Later, when I was a graduate student, these articles became classic must-read books in nuclear physics, so Oppenheimer asked Bate to be the leader of the theory group. A few days after the results of the study, Bate came to Oppenheimer and said that Taylor had a negative role in our group. Why? Bate said: Because Taylor has so many new insights, every morning he comes to talk about two or three new insights, the attention of the young people in the group is attracted by his new insights, taylor in the theory group, so that everyone, especially the young people, are seriously distracted, can not concentrate on the work of developing the atomic bomb, this problem must be solved. Oppenheimer said: What can we think? If you call him up, Taylor won't be satisfied. As a result, Oppenheimer came up with a clever solution. Because Taylor is a person who is free-thinking and likes to think about new things. Oppenheimer thought about it and said, "Well, get Taylor here." Then he said to Taylor, you go and get the leader of a group that specializes in hydrogen bombs. Oppenheimer's intention was to separate Taylor from Bate's theoretical component, and Taylor was very happy. Taylor found a group of several people, he was the head, specializing in how to make hydrogen bombs. For this reason, he began to study hydrogen bombs in 1942, which determined the fate of Taylor's later life. So you see there are also some accidental factors here. Oppenheim defaulted to: first, the hydrogen bomb was ethereal and could not be done for a while; second, if he were to do this anyway, it would solve Bette's problem. This event not only determined Taylor's life, but also had a certain impact on the development of the entire world political pattern. 3)
Hou Yude: You take how Taylor intervened in the study of the hydrogen bomb as an example, indicating that scientists have a certain degree of accident in their choices about some jobs and even life paths. And this is often related to the development of external events. It makes sense that the scientist, like everyone else, has ideas and ambitions, etc., and cannot be completely isolated from society. In connection with this, you said earlier that Oppenheimer was associated with various leftist organizations in the United States at that time, and then there were hearings about him, and these actions of his became evidence of the connection, right?
Yang Zhenning: The story you talked about happened in 1954. In the 50s, from now on, oppenheimer's influence in the whole United States, especially in Washington, was very large, because he presided over the atomic bomb, and the whole world paid great attention to it after the atomic bomb explosion, so Oppenheimer's position in the United States, especially in the United States Congress, had a very great influence. But later, Harry Truman issued an order in 1949 that the United States should go all out to develop hydrogen bombs, because the United States found that the Soviet Union had also built atomic bombs, and Truman made the decision to study hydrogen bombs. After the decision, Taylor was very proud, because this was what he wanted to do, so he asked someone to come and ask these young people to work with him to study how to make a hydrogen bomb. He felt that under the influence of Oppenheimer, some young people refused to go, so from 1949, their relationship became very bad. (Hou: It turns out that the relationship between the two of them has become tense since 1949.) Not in front of the face, but behind the scenes. Taylor later said: I went to this man, and this person was not interested in developing a hydrogen bomb; when I went to the man, the man was not interested in developing a hydrogen bomb, and these people were all influenced by Oppenheimer. This is not a brawl, but a secret struggle. This later spread to the political circles, Because Taylor wanted to build hydrogen bombs, he had close relations with the US military, especially with the Air Department, the Navy Department, and the War Department that coexisted at that time, especially the Air Force was most active in the development of hydrogen bombs, because Taylor had a very close relationship with the US Air Department and the Air Force Minister. The US military wants to develop hydrogen bombs, and from their standpoint, the strength of the army will become stronger when hydrogen bombs develop. From another perspective, the development of hydrogen bomb countries requires a lot of money, which is also mixed with the private interests of some people in the military. In any case, Taylor got involved with the military, especially the Air Force. But in the process of pushing for this, he found great resistance from Oppenheimer, and he realized that only by eliminating Oppenheimer's power and influence could they smoothly develop the hydrogen bomb. This was the background of the hearings in 1954, and they went to Dwight Eisenhower, and at Eisenhower's behest, his men wrote a letter to Oppenheimer saying that we were going to stop you from participating in U.S. defense, and we gave you a choice, and the first option was that you automatically quit, which was the best option. Second, if you disagree and choose to pursue why the government no longer lets you participate in defense work, then we have to hold a hearing. The result was that Oppenheimer did not opt out, so there was a hearing later. The hearing was one of the major events in the world at that time, so you see that all these things are not possible to say in advance that this person is this faction and that person is that faction; the formation of this is very important to the development of the whole international situation.
Hou Yude: So it seems that the emergence of the 1954 hearing was promoted step by step, and it can be said that it is directly related to Taylor. The core problem is that he sees Oppenheimer as a stumbling block to his development of a hydrogen bomb.
Yang Zhenning: Of course, it has a lot to do with Taylor, but there are many reasons for the hearing, and Taylor is just one of the factors. One of the most famous and interesting things at the hearing was that the organizer of the hearing invited Taylor to sit down, Taylor could agree or disagree, many of his friends did not agree to his participation, I had no relationship with this matter, I was his student, and another student of Taylor's contemporary, named Rosenbluth, told Taylor that you don't want to go to the hearing, you go to the public and say something that is very wrong. As a result, he went anyway. Why did everyone advise him not to go? Because this matter is very complicated, why should you get entangled in it? He must go. He later said that he had gone to the hotel room before, walking around until midnight, thinking about what people asked him how he should answer, and he came up with a passage. Really, after the hearing, someone asked him: Dr. Taylor, do you think Dr. Oppenheimer is loyal to the United States? So Taylor took out a passage he had prepared at the hotel, which later became very famous: "I don't think Dr. Oppenheimer is unpatriotic, but I don't know some of his words and deeds, so if the security cause of the United States is not in Oppenheimer's hands, I feel safer." 」 "4) You see he did not say that Oppenheimer was unpatriotic, but because he did not understand his words and deeds, he was not at ease that the national defense matter was in Oppenheimer's hands. This phrase was later widely interpreted as saying that he was going to drive oppenheimer away, which had a great impact on the rest of Taylor's life, because Taylor's personality made him need friends, but he did so, 99% of physicists ignored him.
Hou Yude: At that time, Oppenheimer was very prestigious in the industry and showed excellent leadership ability.
Yang Zhenning: For the vast majority of scientists, this is the case.
Hou Yude: Taylor's words offended Oppenheimer and left a very bad impression on most physicists.
Yang Zhenning: Right. The conflict between Taylor and Oppenheimer may have something else to do with it. There were three important figures in the American scientific community in the 20th century, one was Taylor, one was von Neumann, and the other was Eugene Wigner, who later won the Nobel Prize. I know all three of them well. They were all Hungarians, all Jews who had grown up in Budapest, and important physicists and mathematicians. They were staunchly anti-communist, so they opposed Oppenheimer, more or less closely related to their background, because they considered Oppenheimer to be pro-left. Therefore, there are very complicated reasons for what a person becomes in the end, saying that some people like to have a relationship with politics, and some people do not like to have a relationship with politics, it is too simple. Some people's final life results are not something they can decide on their own, and the role of external others cannot sometimes be ignored.
Hou Yude: I didn't know that Wigner was also firmly anti-communist.
Yang Zhenning: He is also, he is very anti-communist, and it is not only anti-communist. Wigner and I know each other very well, he is twenty years older than me5). In the early 1960s, during three years of natural disasters in China, I heard that many people starved to death in China. One day I went to Wigner's office to discuss something, and when the discussion came, I talked about China, and he said that he was in favor of bombing Beijing with atomic bombs. I can't remember how we talked about this, but I think we must have talked about it when we were discussing the problem of physics, and then we unconsciously talked about it. I said that China is miserable now, and the United States should help China, but his attitude toward China is very unfriendly, not only does not approve of aid, but also supports the Bombing of Beijing by the United States. As a result, I wrote him a letter when I got home, further indicating that I had a completely different attitude from him.
Hou Yude: Can you still find this letter?
Yang Zhenning: If I find this letter, I can show it to you. Wigner is a very thoughtful person, he is a very good physicist, from a research point of view, I like him, he is very early to propose cosmology, but also the earliest application of group theory and symmetry in physics. And I did this too, but later than him, so I admired him. I also admire him personally in many places. But we have fundamental differences in political or social claims. There is also a story related to Wigner. In the 1930s, he traveled from Europe to the United States6), when he first went to Princeton, but did not get a permanent position, so he ran to other places in the middle. 7) It may have been 1938 or 1939, when I don't know if it was Zhou Peiyuan or anyone else who wanted to invite him to China. If you go to Tsinghua and Peking University to check the archives, you should be able to find relevant historical materials. This didn't work out 8). In the middle Wigner went to work at the University of Wisconsin for two years and then back to Princeton9). I don't know why he left? Two years later it was back. But I knew he didn't seem to be happy with the treatment Princeton had given him, so he left. When I mention this, I mean that the three of them are resolutely anti-communist. But their attitude towards whether or not to participate in politics is completely different. The three people are good friends, but they are completely different in terms of attitude and demeanor. 10)
Hou Yude: Zhou Peiyuan was one of the well-known professors who had a good relationship with the Western physics community at that time. When I read Born's biography, I found that after 1933, Born had written to Mr. Zhou expecting him to help arrange work for his students and assistants. In 1936, Mr. Zhou Peiyuan also wrote back to Born, saying that Tsinghua hoped to get a scholar, but it was planned to be implemented after the normalization of relations with Japan. In fact, the Japanese aggression became more rampant, and the matter could only be stopped.11) After you wrote to Wigner, did it affect your personal relationship?
Yang Zhenning: No impact, he did not answer my letter, in fact he could not answer me, my purpose is to show my attitude. Later, we continued to communicate, I invited him to my house for dinner, and he invited me to his house to eat, and did not mention it again.
Hou Yude: You have said in your previous writings that you two have more contacts, and in the article you gave me last year, 12) mentioned the paper he collaborated with Jodan, and his name was written on the front, but he said that yodang actually contributed more.
Yang Zhenning: Yes, this is also a personality of his, doing things honestly. I was very impressed with this story, so I wrote it down. He is indeed a very honest man. 13)
Hou Yude: Wigner is an older generation than you, and that generation of theoretical physicists have a high opinion of him? Relying only on books is very limited.
Yang Zhenning: This involves another relationship. There are many people, including me, who speak highly of him, but many people think he can't do it. Theoretical physicists have a lot of different opinions about how much math to know, like Werner Heisenberg, who, I suppose, all his life felt that Wigner was not a very good physicist, and he thought Wigner was too mathematical. Yes, he did this to Born, and even more so to Wigner, because Wigner was a very good mathematician, and his attitude and knowledge of mathematics was far greater than That of Born, so he looked down on such physicists as Heisenberg in his youth. Wigner himself said in his later years, after winning the Nobel Prize: When I was young, none of my work was valued by others, and today my work is valued whether it is right or wrong. Niels Bohr and Heisenberg disparaged the work of physics in relation to mathematics. But Heisenberg also changed in his later years, and he realized that nothing could be done without mathematics.
Hou Yude: Indeed, I can find enough evidence for this. When Born was in Göttingen, there were many young people around him who were tired of Brian's excessive use of mathematics, perhaps even Fermi in Göttingen. I think it's understandable that some young people who study physics have this kind of thinking. But Fermi's later mathematics was strong.
Yang Zhenning: Right. Fermi was very unhappy when he was in Göttingen, and I think the main thing was that Heisenberg and Wolfgang Pauli looked down on him at the time, which had a big impact on his self-confidence, and Pauli and Heisenberg were very famous at that time. Later, Fermi went to leiden University in the Netherlands and spent half a year in Paul Ehrenfest, where he later said that he regained his self-confidence.
Hou Yude: According to Born's recollection, Fermi showed a very smart and capable side when he was in Göttingen.
Yang Zhenning: If you can write about what Fermi did when he was in Göttingen, and then explore his relationship with Heisenberg, Pauli and Born at that time, I think it will be very important work.
Hou Yude: The key is as you said. He had a little strained relationship with the few people you mentioned or others, and there was nothing between him and Born, as can be seen from the biography of Madame Fermi for Fermi, who was friendly to Fermi, but did not say that others were bad for Fermi.
Yang Zhenning: I have read the biography of Mrs. Fermi, and I have not noticed 14).
Hou Yude: At present, there is no direct evidence in the literature that others are not friendly to Fermi, and it is generally believed that it is because Born is introverted, and which student who takes the initiative to approach him will have more communication with him. But Fermi himself is also an introvert, so they drift apart or always keep a distance. For these can be understood but difficult to argue.
Yang Zhenning: There may be some information revealed in the letters of Heisenberg and Pauli. You can find evidence in these letters and articles of the time, which are important historical documents.
Hou Yude: What you said is very reasonable, and it is worth paying attention to when conditions permit. Fermi was a great experimental and theoretical physicist, a master of both. Other than that, I think he's a very rational person. Oppenheimer set up the Atomic Energy Commission, which included Leo Szilard and others, and later Fermi voluntarily withdrew. He said: "I can not quit, but I can't guarantee that I can make the right conclusions." As a physicist, he can judge whether his work is right or wrong, but he feels uncertain about such complex human affairs, does not know whether the vote he casts is right or wrong, and once he feels this way, he feels that he should quit. This also fully demonstrates his honesty and truth-seeking spirit as a scientist.
Yang Zhenning: I've heard about it too. Oppenheimer admired Fermi's answer, so he told me.
Hou Yude: Is this what Oppenheimer told you directly?
Yang Zhenning: He personally told me. Because he knew I was Fermi's proud student, he went to talk to Fermi unsuccessfully and he came back. Oppenheimer obviously noticed this and admired it, so he told me about Fermi's withdrawal from the Atomic Energy Commission. There is also a story about Fermi 15 about The Cold Spring (Joan Hinton, 1921-2010). She worked as an assistant to Fermi in los Alamos Fermi's laboratory, doing important work on the development of the atomic bomb. After the war, Fermi went to Chicago, and Han Chun became a graduate student at the University of Chicago, and had not yet begun to work on papers. We met in 1947, and she asked me to teach her Chinese, and she didn't tell me why she was studying Chinese, and the next year she suddenly said that she was going to China, and I learned the purpose of her Chinese. I remember very well that she was going to take the train from Chicago to San Francisco and then by boat to Shanghai. In March 1948 I borrowed a car, took her to the Chicago train station, and she began her trip to China. After she arrived in China, we also passed a few postcards, but unfortunately they were all lost. In 1971, when I first returned to China, someone arranged for me to visit Dazhai, but I didn't expect to meet her in Dazhai, and we talked for a long night. Later, some people said that it must have been deliberately arranged by the government, but I think it is not. Why did I go to Dazhai at that time? Because the government department wants me to know the achievements of the agricultural village. Why did she go, because her brother (Handing) was a member of the Communist Party, returned to the United States a few years ago, and returned to China for the first time in 197111111111111,16 she led her brother to China's agricultural areas. So the contingency is very large, not intentionally arranged. During the conversation that night, she told me such a story. When she wanted to come to China in 1948, she said, "I think I must tell Fermi about this." Because her atomic bomb research with Fermi was a sensitive matter, she said, and after thinking about it for half a day, she finally told Fermi that she was going to China. She was terrified that Fermi would tell Washington of her plan and prevent her from coming to China. As a result, Fermi did not tell Washington, and no one stopped her. She said: "I am forever grateful to him for this matter. I thought her words were very important, so when I returned to the United States, I immediately called Mrs. Fermi and said that I had met Han Chun in China, told her about this experience, and especially told her han chun's gratitude to Fermi.
Hou Yude: So can I imagine what would have happened if Ms. Hanchun's mentor hadn't been Fermi? It is likely to end her trip to China.
Yang Zhenning: She was very familiar with Fermi when she was in graduate school, but Fermi was not her mentor. This incident can show Fermi's character very well.
Hou Yude: From the 1960s to the 1970s, documentaries about Dazhai were often played in rural areas, and I learned about Dazhai through movies. When you visited Dazhai, how did you feel?
Yang Zhenning: They did a good job of publicity, Chen Yonggui entertained me, everyone who visited lived in the guest house, and Han Chun also lived there, so I met. Chen Yonggui took us to see the fields planted by the Dazhai people on their own.
Hou Yude: Combining these things, I have a deeper understanding of Fermi. Born said that some scientists forget their jobs and devote themselves to politics excessively, and believe that this has to do with human character. I think there's some truth to his words. Some people are active and responsible, and some people are introverted and timid.
Yang Zhenning: This is a very complicated issue, for fame and fortune, power and money, everyone in different industries around the world has their own judgment, the living environment and personality are different, the judgment he makes is slightly different, it may produce a big difference in life, so the final result is closely related to the growth environment of people and the social turmoil at that time. In this regard, the traditional Chinese Confucian way of being a man is also different from that of the West. The Confucian tradition of self-cultivation, etiquette and other concepts are relatively conservative, the West does not oppose this, but they do not pay enough attention, so they are more outward, Confucianism is more inward, there is a difference in this point. The impact of this cultural distinction on people cannot be ignored. This cultural distinction between who is good and who is bad is not a simple question that can be answered, and there will be different ideas in different situations and at different times.
Hou Yude: Since we mention Oppenheimer, Fermi and the atomic bomb, this reminds me of Einstein. At that time, Einstein, together with Silard and others, wrote a letter to the President of the United States proposing the development of an atomic bomb. Do you think this letter worked?
Yang Zhenning: I think this letter played a role, but it did not play a big role. Unfortunately, there are people in China's academic circles who are lonely and unheard of and give their opinions indiscriminately. After Einstein's letter was sent, it was initially not noticed by the U.S. government. This is not unusual, as government is so large that it usually ignores academic matters. Einstein was very famous, but many people thought that he was an old gentleman, now outdated, a man who had little to do with the world, so it was not unusual for people in the U.S. government not to be interested in this letter. But then I didn't know exactly what happened, but it turned out that the U.S. government was a little more interested in the letter, so when the United States began to build an atomic bomb, it was related to the letter. That's why I say that the letter didn't have a big impact, and the impact wasn't immediate, but it did happen in the end. I think this is the most accurate assessment. Last time I told you about Peng Yue, he studied the history of the atomic bomb and read more than ten books before he wrote a very good article. Some Scholars in China do not read books steadily, so they are lonely and unheard, and it is inevitable that the opinions expressed in this way will be wrong.
Hou Yude: You are quite right, in fact, as far as I know, there are some scholars in China who are now doing very rigorous research work. But as long as there is a human group, there is often an approximate normal distribution. China's market economy was full of counterfeiting in the early days, and later businessmen found that it was impossible to make money by cheating, so the economically developed areas consciously became more and more standardized, and the quality of products became better and better. I expect the same from Chinese academia. Just talking about the atomic bomb, I suddenly had a thought: When your mentor Taylor was engaged in hydrogen bombs, you had the opportunity to intervene, why didn't you intervene?
Yang Zhenning: I left Chicago in 1949, and I've been in Princeton for the next 17 years, and I can occasionally see Taylor because he sometimes comes to Princeton for meetings, and he can also see them at meetings at the American Physical Society, but in general, very little. When we meet, we talk about hello, how are you, and so on. After I left Chicago, I had several longer conversations with him, none of which had anything to do with hydrogen bomb research. The first time I had a relatively long exchange with him, half an hour, less than an hour, was in the summer of 1955 when I visited Berkeley, and he asked me to talk about it, and it had nothing to do with nuclear weapons. I remember talking about two things, one was that he asked about the gauge field, because by then my article with Mills had been published. He was probably slightly interested, and he asked me a little question, but didn't go deeper. And the other one was, he said to me... I don't remember if I proposed it or if he did it, maybe I did, but we talked about it. At that time, his conflict with Oppenheimer was known to the whole world, and I remember as if I said to him, I think it is best for him to do something to make up for it, how to make up for it? Because he had just received the Henrique Fermi Award from the President of the United States 17). Fermi died in 1954, and when he was very ill before his death, the United States Congress passed a decree establishing an Enrique Fermi Prize. There were a lot of prize money at the time, the first one was given to Fermi 18), this prize has always existed, and now there are 19). So I told Taylor, you just won the Fermi Award, why don't you nominate Oppenheimer once? Taylor was later nominated for Oppenheimer, and the following year Oppenheimer won the Fermi Award. But I guess it can't be attributed to me, I think he thought of it himself, and I'm sure others will remind him that this is a good way to make up for it. But at least I remember talking to him about it. I remember I probably wrote him a letter later about it.
Hou Yude: You mentioned the letter, and I will trouble you again, and if you find the letter to Wigner, you must show it to me.
Yang Zhenning: Okay. I went on to remember Tyler. Taylor and I never talked about the hydrogen bomb, and then there was such a contact, and when I went to Beijing in 1971, it was very interesting, and the American newspapers came out at that time. He was very careful because first I was his student, and second he was very influential in Washington at the time. He had a nephew who was a professor, and I knew him well. He's almost 80 years old now, and he says his uncle is coming to see him and he wants to talk to me about China. So that day he invited only me and Taylor to his house for dinner, and after the meal Taylor took me to a room where his nephew led his wife away. Taylor and I talked alone, and it was clear that Taylor wanted to know about China, and I was willing to tell him. We talked for hours. When it comes to the impression of China, he doesn't like the Communist Party, but he's not as fierce as Wigner, who once said he was going to bomb Beijing.
Hou Yude: Speaking of which, I think it is necessary for me to confirm, is Wigner talking about bombing in the general sense, or bombing with nuclear weapons? Can this be discerned in the context of the time?
Yang Zhenning: This dialogue was relatively early, and it is not that they really have a plan to bomb Beijing. I feel that Wigner said this mainly to express his opposition to the Chinese Communist Party. But if the U.S. government does discuss the matter, Wigner will support the bombing opinion. That night we were talking about Taylor wanting to know what china was like, and he wanted to know what my opinion was on China. Is it possible that he wants to test whether I want to go back to China? I can't tell. He knew I had nothing to do with atomic weapons, and he would guess that China very much wanted me to go back, not just to do scientific work, he guessed that if I went back to China, China would let me do the work of the atomic bomb. I think he might test my opinion. Taylor and the U.S. military are very familiar, the military may let him test me, is this possible? This is a very complex issue. Because I am a very famous physicist in the United States, ordinary people outside the scientific community, such as people in the US military, think that physicists and the atomic bomb are very close, but they are not close. For example, when I went to Hong Kong at the end of 1964, my father, mother, younger siblings came to Hong Kong from Shanghai, and we met and stayed together for two weeks. When I came back to Princeton, there was a professor named George Kennan, who was an important figure in American diplomacy and one of the most important figures in diplomatic theory. When the United States and the Soviet Union became two camps in the 1940s, how should the United States handle its relations with the Soviet Union? There was an article at the time that invented a point called containment policy, which is to fence it off, which was the most important thing in diplomatic theory after World War II, and the author died four or five years ago, a few years older than me. He later became a professor at Princeton. When I returned to the United States from Hong Kong in 1964 after I was separated from my parents, he invited me to dinner and asked me a lot about China from my parents, and I later suspected that he might have also wanted to test whether I wanted to go back to China when I came into contact with my parents. I suspect it might be the U.S. Foreign Office that made him tentative. In other words, some people in the US government are very concerned about whether Yang Zhenning is returning to China. Before I returned home in 1971, I wrote a letter to the president of the United States, why did I write him a letter? If I suddenly appear in China without telling him, there may be a dispute, so I think I might as well tell him in advance. I wrote him a letter, and he replied that he was glad that I could return home to visit, but could not give me a visa, in fact I did not need his help at that time. Not long after this incident, a classmate I hadn't seen in years at the University of Chicago suddenly came to see me, and I think I hadn't heard from him for at least a decade. He stayed at my house for a day, and I later guessed that he might have come at the behest of some U.S. department. Why do I think that? He studied at the University of Chicago as a journalist, stationed in Hong Kong, and he did one thing in Hong Kong, the most important thing in his life, that is, he visited Zhang Guotao in Hong Kong and wrote a biography of Zhang Guotao, which established his position among journalists, because Zhang Guotao is an important historical figure. So I guessed he probably had some relationship with the U.S. government, and I didn't ask him later. So these people, including Taylor's visit, I more or less feel that they want to test whether Yang Zhenning wants to return to China.
Hou Yude: Thank you for talking so much about the first topic, part of which I knew before, and part of which I heard about for the first time. It's so informative that I feel we can end the first question here. The second question I look forward to asking you today is about the relationship between physics and philosophy. Few people who do experimental physics seem to care about this problem. Some theoretical physicists were concerned about it, such as Bohr, who especially liked to discuss philosophy, and Born, who sometimes said that philosophy was important and required students to know something about philosophy, but he warned students not to submit completely to any school of philosophy, but to maintain a spirit of questioning and criticism. There are also some theoretical physicists such as Fermi and Feynman who have an unfriendly, even dismissive, attitude toward philosophy. I have noticed that your previous view on this was that you thought that philosophy was positive for physics earlier in history, but as physics developed, the influence of philosophy on physics became weaker and weaker. What do you think about the relationship between the two now?
Yang Zhenning: Regarding the relationship between philosophy and physics, yes, the views of the physics community in different eras are different. That is to say, this relationship is constantly changing with the passage of time and with the evolution of physics. In the 19th century, because of the tradition of science called natural philosophy, science was still considered to be closely related to philosophy. By the end of the 19th century, many scientists believed that physics was almost born out of philosophy, especially Mach's influence was very large. But you see today, even in the 20th century, when I was doing research at the frontiers of physics, the physicists who were actually working on research, no one paid attention to philosophy. This means that between the 19th and 20th centuries, physicists' views on the philosophy of philosophers 20) changed greatly. This change is presented in different people. Of course, some physicists of the same era like to talk about philosophy, and some people don't like to talk about philosophy. You're right, for example, Bohr likes to talk about philosophy, Fermi doesn't like to talk about philosophy, and it's inevitable that there will be a different distinction. This may be because different people have different hobbies, and the key to the problem is to see whether philosophy really guides the study of physics, and whether physicists cannot leave philosophy. At least from my generation of physicists, I don't think so.
Hou Yude: In fact, there is a reversal today, as you said, now it is not philosophy that influences or directs the study of physics, but physics that influences the development of philosophy.
Yang Zhenning: Yes, to be specific, I think the development of quantum mechanics is a good example, quantum mechanics is not from philosophy, although some people think so, but I think it is not; it is obvious that quantum mechanics is established from the study of atomic spectra. After the development of quantum mechanics, it in turn had a great influence on the philosophical community, and this process is still continuing.
Hou Yude: There is a fundamental difference between the microscopic world and the macroscopic world that quantum mechanics focuses on, and in the first 30 years of the 20th century, this field was not only unfamiliar and newly developed for physicists, but the research results were completely new to philosophers, so he must absorb, learn, and understand this new thing, and this process will inevitably appear. Your personal opinion is that there is no need for a physicist to study philosophical works first, and then use them to form his own way of thinking, thus influencing the research work of physics.
Yang Zhenning: To respect the objective facts of the scientific research process, I have not studied philosophy, and none of the theoretical physicists I have met treat philosophy as if they had to learn and use mathematics. Shoichi Sakata believes that theoretical physics research needs philosophical guidance, I said 21), I disagree with his view that his research originated in philosophy, he can't draw conclusions about physics from philosophy, and I think that the less he deals with philosophy, the greater his physical achievements.
Hou Yude: In this way, your basic views on the relationship between physics and philosophy are highly consistent with 30 years ago. Thank you for answering my question clearly.
concentrate:
1) By William Poundstone, translated by Wu Heling. The Prisoner's Dilemma. Beijing: Beijing Institute of Technology Press, 2005, 5 pp.
2) In his biography, Wigner also mentions the articles that Bate published between 1936 and 1937, calling them "wonderful papers." For details, see Chapter 10, Page 149 of The Scholar in trouble: Wigner's Autobiography, published by Shanghai Science and Technology Education Publishing House in 2001.
3) The Manhattan Project involved a large number of first-class physicists with personalities, and the interpersonal relationships were more complicated, and there were many different stories from the perspective of different people. Mr. Yang Zhenning's story of Oppenheimer's proper arrangement of Taylor is echoed in Taylor's biography, such as saying: "After arriving in Chicago, he (referring to Taylor) was not assigned any specific work. In addition to the sadness, his mind that kept thinking turned back to the theoretical discussion of the hydrogen bomb. For more information, see: Stanley Bloomberg, Gwen Owens, Hua Junduo, Zhao Shuyun translation. The father of the American hydrogen bomb, Taylor. Beijing: Atomic Energy Press, 1991, 118 pp.
4) From Taylor's perspective, taylor's biographer argues: "In the postwar years, Edward Taylor found Oppenheimer's political views not only disturbing, but sometimes elusive. "This was especially true in 1953. See: Stanley Bloomberg, Gwen Owens, Hua Junduo, Zhao Shuyun, trans. The father of the American hydrogen bomb, Taylor. Beijing: Atomic Energy Press, 1991, 299 pp. In this way, Taylor's famous words are not only his cautious and intelligent and lethal wording, but perhaps at least partly the true thoughts of his heart.
5) Mr. Yang Zhenning remembers very accurately, Wigner was born in 1902, and Mr. Yang was born in 1922.
6) Wigner himself said in his biography that in October 1930 he received a semester lecturership at Princeton University in Berlin, and he came to the United States. Satisfied with the work of Wigner and von Neumann, who arrived almost at the same time as him, Princeton proposed that over the next 5 years, the two of them could work at Princeton for half a year and the Europe they wanted to go to for half a year. From 1935 to 1936 Princeton offered Wigner the position of full-time visiting professor. For details, see chapters 9 and 147-148 of Chapter 10 of The Scholar in trouble: Wigner's Autobiography published by Shanghai Science and Technology Education Publishing House in 2001.
7) Wigner said in his biography that Princeton university fired him in 1936. The University of Wisconsin-Madison then offered him an acting professorship. For details, see pages 153 and 157 of Chapter 10 of The Scholar in trouble: Wigner's Autobiography published by Shanghai Science and Technology Education Publishing House in 2001.
8) Combined with Wigner's own recollection, Princeton University had already provided Wigner with a teaching position again in 1938, which inferred that Zhou Peiyuan planned to introduce Wigner, probably earlier than in 1938-1939.
9) On June 13, 1938, Princeton University again offered Wigner the position of professor of mathematical physics. For details, see Chapter 10, Page 161 of The Scholar in trouble: Wigner's Autobiography published by Shanghai Science and Technology Education Publishing House in 2001.
10) Yang Zhenning once said that Oppenheimer, Taylor and other American scientists are sharp and flaunt themselves. See: Yang Zhenning. Sixty-Eight Years of Heart Road: 1945-2012.Beijing: Life, Reading, and Xinzhi Triptych Bookstore, 2014 edition, p. 233. But Yang Zhenning said: "Wigner is a sincere person, not smiling, and the attitude of American scientists is completely different." For details, see: Yang Zhenning, Weng Fan compilation. Dawn set. Beijing: Life, Reading, and Xinzhi Triptych Bookstore, 2008 edition, p. 53.
11) For details, see page 187 of Hou Yude's article "Translation of a Letter from Born to Peng Huanwu" published in physics in the 3rd issue of 2015.
12)详见：YANG C N. Fermi’ s β-decay theory. International Journal of Modern Physics A，2012(3＆4)，27：1—7.
13) Yang Zhenning took this opportunity to point out that Chinese scholars and the Chinese he saw, and that they were dishonest in their actions and speeches, and that he was critical and worried about them.
14) In Fermi's biography, Madame Fermi wrote: "Born himself was gracious and hospitable. For details, see page 33 of Fermi's biography, published by the Commercial Press in 1998.
15) In 2008 (when Hanchun was still alive) In Yang Zhenning's "Dawn collection" published by the Life, Reading, and Xinzhi Sanlian Bookstore, Yang Zhenning told a general synopsis of this story, which can be found on pages 314-315 of the book.
16) The accurate fact is that Han Ding went to China with the United Nations Relief Administration in 1947 and came to the Liberated Areas to resume production and train agricultural machinery personnel, and he did not return to the United States until 1953. He returned to China in 1971 at the invitation of Premier Zhou after years of absence.
17) The data shows that Taylor won the 1962 Fermi Prize, so Mr. Yang said that in 1955 they talked about nominating oppenheimer, and there may be an error in time memory.
18) Current data shows that the first recipient of the Fermi Prize was von Neumann, mentioned several times above, and perhaps Mr. Yang has a wrong memory.
19) Yang Zhenning won the Fermi Prize in 1979.
20) Yang Zhenning once pointed out that philosophy has two meanings, one is the philosophy of philosophers, and the other is the view of long and medium distances (even short distances) on physics problems. This view is closely related to a person's style and preferences. For details, see pages 513-514 of the Collected Works of Yang Zhenning, published by East China Normal University Press in 1998.
21) Yang Zhenning put forward this statement in a report made by the Graduate School of the University of Science and Technology of China (Beijing) in 1986. For details, see page 514 of the Collected Works of Yang Zhenning published by East China Normal University Press in 1998.
This article is reprinted with permission from the WeChat public account "Chinese Physical Society Journal Network".