No Regrets for Unfulfilled Ambitions

This post is the translation of my contribution, originally published in Japanese in the alumni magazine of my alma mater, Kanazawa Kindai Senior High School (presently Kanazawa Commercial High School), Kinsho–Kindai Press, No. 64, pages 26–27 (2024). The English of the translation has been improved with the aid of ChatGPT.

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The photograph captures a moment from 1998 when I was invited to Kharkiv University in Ukraine. Now, I find myself concerned about the fate of those who warmly welcomed me then, amidst Russia's ongoing military incursion.
Seventy years have elapsed since I finished high school, and I am honored to commemorate this milestone with a written piece. Reflecting on my contributions to this magazine, I recall writing about my travel to a summer academic conference in Southeast Canada in the 20th issue (1980), which celebrated the school's 80th anniversary. Subsequently, in the 47th issue (2007), I penned an article on the newspaper club alumni association titled "Ten Gatherings." Furthermore, my essay "Guash Painting as a Hobby," initially published in a booklet by the Kansai branch, was reprinted in the 63rd issue (2023). From these writings, readers might deduce my involvement in the newspaper club during my school days, my subsequent engagement in research with international conference participation, either in the realm of sciences or humanities, and my leisure pursuit of watercolor painting, but no more.

Allow me to supplement the above information with that of my school years. An excerpt from the Kinsho–Kindai Centennial History (2000) sheds light on my involvement with the student council magazine Shinju:

In the initial issues, a strong literary trend prevailed. However, from the fourth issue, scholarly articles emerged, [including] Tatsuo Tabata's "The Use of 'with' in Alice's Adventures in Wonderland.''

The fourth issue referred to above coincided with my second year at school. The actual title of my contribution was simply "Alice's Adventures in Wonderland," and its content was not an article but a personal essay. The essay appreciated the opening sections of Lewis Carroll's Alice's Adventures in Wonderland, a text I encountered in Principal Akiyama's English class, evoking analytic reflections on Carroll's prose. Consequently, it may have been perceived as a research paper. In the subsequent fifth issue of Shinju, at the behest of my homeroom teacher, Mr. Sakai, who also taught me English, I authored a partial Japanese translation of the English literary work The Private Papers of Henry Ryecroft. Concurrently, inspired by Mr. Kuwayama, who had assigned us Japanese language homework the previous summer, I submitted a piece of fiction titled "A Star Shining in the Summer Sky," which I had written for said homework. Initially hesitant to submit what I deemed an immature work, I eventually acquiesced to Mr. Kuwayama's advice, who assured me, "It will serve as a cherished memento." The primary focus of my classmates' intrigue was identifying the inspiration behind the female protagonist.

This additional information may portray me solely as a humanities enthusiast. However, I pursued scientific endeavors, receiving the Takamine Prize (See "Note added to the reprint edition") and enrolling in the Faculty of Science at Kyoto University. My decision to join Kyoto University was chiefly motivated by my aspiration to study theoretical particle physics under the tutelage of Dr. Hideki Yukawa, Japan's inaugural Nobel laureate, and emulate his groundbreaking achievements. Following my receipt of the Takamine Prize, close friends even jested, "You're destined for the Nobel Prize next!" However, during my final year of university, I opted to specialize in experimental nuclear physics, a decision influenced by various factors. Subsequently, upon completing my master's degree, I joined the Radiation Center of Osaka Prefecture, established by Professor Kiichi Kimura, my mentor in the specialty. I earned my Ph.D. in science through an electron backscattering experiment. In 1990, following the center's amalgamation into Osaka Prefecture University (now Osaka Metropolitan University), my designation transitioned from senior researcher to professor. I retired in 1999, honored with the title of Professor Emeritus. Since then, I have continued my modest research work at my fictitious private institutes, the names of which are given on my website.

Although my ambitions did not materialize precisely as envisioned, I enjoyed a fulfilling research career, contributing a few papers that continue to be cited even after five decades. Consequently, I harbor no regrets regarding my erstwhile aspirations. My enduring reverence for Dr. Yukawa allowed me to delve into his Nobel Prize-winning work alongside fellow physics enthusiasts as an advisor for the "Citizens' Association for Research on Hideki Yukawa," active at the Osaka Science Museum for the centenary of his birth in 2007. Furthermore, I fondly recall delivering a lecture titled "The Influence of the Chinese Classics on Yukawa's Work" at a Kyoto University alumni local gathering in Himeji in 2010. I urge current students of our alma mater and young alumni to have ambitions, for they will foster a meaningful and fulfilling life.

Note added to the reprint version: The Takamine Prize is one of the programs run by the Dr. Takamine Jokichi Memorial Association, which was established in the spring of 1945 to honor the achievements of Dr. Takamine Jokichi, a great scientist and international figure born in Kanazawa, and to promote science education. The first Takamine Prize was awarded in 1951. On those days, 10 students (5 each for the main and secondary prizes) outstanding in science and chemistry were selected from junior and senior high school students in Ishikawa Prefecture, respectively. At the 21st award in 1971, a school prize was established in addition to the individual prize, and high school students were instead excluded from the nominees. (Reference was made to the Kanazawa City website.)

On Kamefuchi's Essay about Heisenberg and Yukawa (6)

References [25–28] of this article.

4 Different methods of theoretical physics research

Kamefuchi divides the methods of theoretical physics research into the "ascending type" and the "descending type" to explain why Heisenberg's and Yukawa's later studies were unfinished. In the "ascending type," the researcher "builds up the theory from the basic points." In the "descending type," he or she "sets a hypothetical principle at a high level far beyond the existing theoretical system and descends from there to try to deduce all the laws of physics. Kamefuchi adds, "In the latter method, one has to rely on intuition or analogy. Neither of these has objectivity or inevitability. So, mostly one goes astray." He then infers: Both Heisenberg and Yukawa achieved results by the former method in the first half of their career. However, they turned to the latter type in the second half, failing to complete the research.

Yoichiro Nambu also described a similar classification of research methods [25, 26]. Kamefuchi thinks that the research method can change between the first and the second half for one researcher. On the other hand, Nambu names them by the proper name of famous physicists as if a researcher uses a single method throughout his or her life. However, we should understand each of them to be the one related to the representative, successful research done by the physicist used for the naming. Nambu calls his categories "Yukawa mode" and "Dirac mode" in [25]. As an explanation, I will introduce a concise one in the book by Michio Kaku and Jennifer Thompson [27].

The Yukawa mode is deeply rooted in experimental data. Yukawa was led to his seminal idea of the meson as the carrier of the nuclear force by closely analyzing the data available to him. The Dirac mode, however, is the wild, speculative leap in mathematical logic that led to astonishing discoveries, such as Dirac's theory of antimatter or his theory of the monopole [...]. Einstein's theory of general relativity would fit into the Dirac mode. ([27] p. 85)

Later, Nambu modified this and divided his classification into three types. [26] The explanation for each is as follows.

• Einstein mode (top-down): To create a theory by assuming that "nature should follow this principle." Example: Einstein's theory of gravity (general theory of relativity), made under the assumption that "in general, space may be curved."
• Yukawa mode (bottom-up): To start from the working assumption that "behind the new phenomenon, there is some new field or particle, apart from deep reasons." Examples: Yukawa's meson theory and Pauli's neutrino hypothesis.
• Dirac mode (from heaven): To assume that a mathematically beautiful theory should be true. Examples: Dirac's monopole theory, supersymmetry theory, and string theory, currently being explored.

Einstein's general theory of relativity, which was an example of the Dirac type at the stage of literature [25], was promoted to the independent one. As a result, the Einstein type (top-down) and the Yukawa type (bottom-up) have become equivalent to Kamefuchi's "descending type" and "ascending type," respectively. Nambu states about the examples of Dirac-type as follows. 'The existence of the monopole is now the natural consequence of the quantum field theory, but we still need to confirm it by observation. Studies of supersymmetry and string theories are currently in full swing, so we can say that it is "the heyday of Dirac mode" nowadays.' However, the success or failure of these theories is still unclear, and it is interesting to keep an eye on what a future comes for the high energy physics theory.

By the way, I wonder if Einstein's general theory of relativity is entirely top-down. This is because it is known that there was a thought experiment at the starting point for him to come up with this theory as quoted by Holton ([28], p. 78): "For him, at least in the vicinity, there is no gravitational field during the fall, for example, given an observer who falls freely from the roof." Kamefuchi does not state that Einstein's mode of thinking had been top-down since the time of the general theory of relativity. Instead, he writes that Einstein also turned to the use of the top-down method in the 30 years of his later life for trying unsuccessfully to unify the gravitational and electromagnetic fields.

Here I would like to add the story in Kaku and Thompson's book [27] that Nambu's friends named a type that combines the first two classifications by Nambu "Nambu Mode." They made this naming in commemoration of Nambu's 65th birthday (1985). I quote the related part below.

[...] This mode combines the best features of both modes of thinking and tries carefully to interprete the experimental data by proposing imaginative, brilliant, and even wild mathematics. The superstring theory owes much of its origin to the Nambu mode of thinking.
Perhaps some of Nambu's style can be traced to the clash of Eastern and Western influences represented by his grandfather and father. [...] ([27] p. 85)

Acknowledgement

I heartily thank Naoki Toyota, Professor Emeritus, Tohoku University, for his telling me that there is a story in Ref. [10] that Bohr criticized Pauli's lecture as well as for his other useful suggestions provided by email exchanges on the topic of this article.

References

25. Y. Nambu, "Direction of particle physics," in Proc. Kyoto Int. Symp.: The Jubilee of the Meson Theory, Kyoto, Aug. 15–17, 1985, edited by M. Bando, R. Kawabe, and N. Nakanishi; Prog. Theor. Phys. Suppl. No. 85, 104 (1985).
26. Y. Nambu, One Hundred Years of Elementary Particle Physics (International Institute for Advanced Studies, Kizugawa, Kyoto Prefect., 2000) in Japanese.
27. M. Kaku and J. Thompson, Beyond Einstein: The Cosmic Quest for the Theory of the Universe (Oxford University Press, Oxford, N. Y., 1997; first edition, Bantam, 1987).
28. G. Holton, "What, precisely, is "thinking"? ...Einstein's answer," in Einstein, History, and Other Passions (AIP Press, Woodbury, 1995) p. 74. [See also "On trying to understand scientific genius," in Thematic Origins of Scientific Thought: Kepler to Einstein, Revised edition (Harvard University Press, Cambridge, Mass., 1988) p. 371.]

(End)
Search word: Kamefuchi-2020

On Kamefuchi's Essay about Heisenberg and Yukawa (5)

References [15, 18, 22] of this article.

3 Yukawa's tragedy

3.1 Yukawa's research at that time

Kamefuchi writes, "The lectures progressed, and Yukawa called up K's name for the presentation of his paper co-authored with collaborator K, "Space-time picture of elementary particles." K is Yasuhisa Katayama (1926–1978), familiar to those who know about Yukawa's later studies (as for the bibliographic information of the paper published in the proceedings, see Ref. [3] given in the first part of this article). This research belongs to the work of elementary domain theory that Yukawa worked on with coworkers in his later years. About this work, Yukawa writes in the "Preface" of Ref. [15], "I was able to formulate a theory in 1967 with the great efforts of Mr. Yasuhisa Katayama." Yukawa continued somewhat proudly, "The following year, I was able to publish a paper co-authored with Katayama and a paper with the additional coworker, Umemura." These papers are Refs. [16] and [17].

Three years later, Yukawa wrote Preface and "Part V Unified Theory of Elementary Particles" as the supervisor of Ref. [18]. In them, he frankly writes the reaction of academia to the theory of elementary domains and his own thought as follows:

In Part V, we decided to follow a path towards a unified theory. It will not be the only way, nor is it guaranteed to reach its goal. On the contrary, it is the path that many researchers consider to be the largest deviation from the legitimate one. ([18], Preface, p. vii)

If we proceed in this direction, we may, in the end, have to run into the problem of the quantization of space-time itself in some sense. The concept of the elementary domain itself may still be incomplete in that it assumes the Minkowski space behind it as a four-dimensional continuum. However, all the elucidation remains in the future. ([18] Part V, p. 608–609)

3.2 Impact and evaluation of Yukawa's research at that time

Looking up the number of citations of papers [16] and [17] by Yukawa and his coworkers on Google Scholar, we find the number 46 only for [17]. I have noticed from the number of citations of my own papers that Google Scholar's statistics are inaccurate. For example, if there are similar titles, they are sometimes wrongly regarded as the same paper. Therefore, for [16] and [17], I would like to use, instead of Google Scholar's, the numbers in the journal Progress of Theoretical Physics and at the Crossref site linked to it. Using the sum of the number of citations from these two sources (no duplication of citing papers between the two), it is 39 for [16] and 28 for [17]. Compared to Yukawa's Nobel Prize-winning paper [19], which has more than 2,400 citations (according to Google Scholar), the former numbers are small. However, there might be a possibility that Yukawa's work on the elementary domain will make new contributions to the development of particle theory in the future. I would like to quote an experts' view on this point.

Nicholas Kemmer (1911–1998), who was a Russian-born nuclear physicist working in Britain, described Yukawa's research after the 1940s in reference [20] as follows.

Yukawa devoted the greater part of his subsequent life as a research worker to the quest for a better, deeper fundamental theory. He published over twenty papers spanning a period of twenty years developing various approaches to this goal. Central to his thinking was the belief that the association of any elementary particle with a single geometrical point in space was in some deep sense mistaken; the key concept in many of his publications is the 'non-local field'. [...] We cannot see into the future and say with confidence that all the ideas presented in these papers are lacking in any grains of deeper truth that we do not yet perceive. And we cannot measure the stimulation that readers of his papers on the way to developing ideas of their own may have received. Even so it is a fact that in present day work one would be hard put to find reference to or influence of his later publications.

Kemmer's words are a modest statement that Yukawa's second half research was barren.

Professor Emeritus Laurie Brown, who is an American theoretical physicist and historian on quantum field theory and particle physics, stated in Ref. [21] as follows.

The idea of nonlocal fields (which is to be distinguished from the idea of local fields having nonlocal interaction) gradually became a theory of elementary particles with internal structure. By the late 1960’s it was superseded by Yukawa’s concept of "elementary domain", based upon the quantization of the classical continuously deformable body. These fundamental ideas do not play a major role in current theoretical physics but may well be vindicated in a future physics.

Here, the last words after "but" give Yukawa fans (I am one of them) hopes for the future. However, Brown, similarly to Kemmer, seems to have added these words in honor of Yukawa, who had established meson theory and the method of particle physics at a young age.

Sho Tanaka (1928–2019), a particle physicist and emeritus professor at Kyoto University, introduces Japanese-born researchers' evaluation of Yukawa's postwar research together with his own views [22]. Here, I would like to quote Yoichiro Nambu's words about "Dr. Yukawa's postwar research activities," which seem to be the outspoken and sharpest criticism.

Unfortunately, [Yukawa's postwar research] was not very fruitful. Aside from the relentless efforts he made to understand elementary particles as things with a geometric spread, the content and method seem to have been too naive. With the development of the gauge field theory, the geometrical view has become very important, and there is a possibility that the internal quantum numbers may be reduced to geometry. However, it cannot be said that his idea was a seed of these developments. The influence he had on younger Japanese scholars since the theory of mesons was more indirect. (Quoted from [23]; [22] p. 311)

Tanaka himself points out in Ref. [24] that the D0 brane of string theory is close to the idea of ​​Yukawa's elementary domain. However, this may be one of the developments that Nambu considers as independent of Yukawa's idea.

Next time, I would like to think about different research styles of theoretical physics in connection with Kamefuchi's thought about the common reason why the research of Heisenberg and Yukawa around the time of the "tragedy" ended unfinished.

References

15. H. Yukawa, Hideki Yukawa Self-Selected Works Vo. 2 (Asahi Shimbun, Tokyo, 1971) in Japanese.
16. Y. Katayama and H. Yukawa, "Field theory of elementary domains and particles. I," Prog. Theor. Phys. Suppl., 41, 1 (1968).
17. Y. Katayama, I. Umemura, and H. Yukawa, "Field theory of elementary domains and particles. II," Prog. Theor. Phys. Suppl., 41, 22 (1968).
18. H. Yukawa, supervisor, Iwanami Lectures: Basics of Modern Physics Vol. 11, Elementary Particle Theory (Iwanami, Tokyo, 1974) in Japanese.
19. H. Yukawa, "On the interaction of elementary particles. I," Proc. Phys.–Math. Soc. Japan (3) 17, 48 (1935).
20. N. Kemmer, "Hideki Yukawa. 23 January 1907–8 September 1981," Biographical Memoirs of Fellows of the Royal Society, 29, 661 (1983). JSTOR, https://www.jstor.org/stable/769816. Accessed July 30, 2020.
21. L. M. Brown, "Yukawa, Hideki," in Complete Dictionary of Scientific Biography (Charles Scribner's Sons, New York, 2008); online version of this article available at
    https://www.encyclopedia.com/people/science-and-technology/physics-biographies/hideki-yukawa. Accessed July 31, 2020.
22. S. Tanaka, Hideki Yukawa and Einstein (Iwanami, Tokyo, 2008) in Japanese.
23. Y. Nambu, "Dr. Yukawa and Physics in Japan," Kagaku 52, No. 2 (1982) in Japanese.
24. S. Tanaka, "From Yukawa to M-theory," in Proc. Int. Symposium on Hadron Spectroscopy, Chiral Symmetry and Relativistic Description of Bound Systems, Nihon Daigaku Kaikan, Feb. 24-26, 2003; KEK Proceedings 2003-7, edited by S. Ishida et al. (KEK, Tsukuba, 2003) p. 3; also available as arXiv:hep-th/0306047.

(To be continued)
Search word: Kamefuchi-2020
Search word: Kamefuchi-2020

On Kamefuchi's Essay about Heisenberg and Yukawa (1)

Kamefuchi's essay published in the magazine Tosho

1. Introduction

Recently, I read the essay "The life of heroes" [1] by theoretical physicist and Professor Emeritus of the University of Tsukuba, Susumu Kamefuchi. The heroes mean here two giants in his field, Werner Heisenberg and Hideki Yukawa. What the author writes is "witness testimony" of the heroes' tragedies in their later years.

Heisenberg's tragedy occurred at the International Conference on High Energy Physics held at CERN in July 1958. The chairperson Pauli began to attack violently against his lecture, denying his study [2] altogether.

Yukawa's tragic incident happened at the International Conference on Particles and Fields held at the University of Rochester in August 1967. He was chairing a session, and his collaborator K was going to give a talk on the paper [3] co-authored with the former. Then, most of the audience stood up from their seats and left the room.

The author writes that he was worried about degrading the heroes, but that he recalled it essential to convey the truth.

In the present article, I describe and discuss some of the things I learned from other sources in connection with Kamefuchi's essay.

2 Heisenberg's tragedy

2.1 Description in Polkinghorne's book

Kamefuchi begins to write the stories saying, "these seem not much talked about." However, I recently read the same story about Heisenberg in a book [4]. The author of the book is a British theoretical physicist, theologian, and Anglican priest, Polkinghorne. He describes twenty international conferences on high energy physics from 1950 to 1980 to make this book a unique history book of this field of research. In the book, Polkinghorne writes in a slightly more detailed manner than in Kamefuchi's essay by citing, from the proceedings, Pauli's words of the attack on Heisenberg's speech. The book also has a photo of Pauli at that time, with the caption including his remark, "No credits for the future," on Heisenberg's speech. The story ends with the following words, which are sympathetic to Heisenberg.

It was a scene at once farcical and sad. Justification lay with the sceptical Pauli but Heisenberg was one of the greatest physicists of the twentieth century who should have been able to enjoy a more dignified close to his career. ([4] p. 77)

Readers of this article may wonder that the book on the history of physics contains emotional words, so I would like to add some explanations about the character of this book. This is not a textbook with an objective description or a non-emotional scholarly book, but a book for the general public. (The general public here might be limited to those who are mainly interested in science. I read this book as a person who thinks high energy physics as one of his hobbies.) Thus, the descriptions in this book are rather light-hearted and make fun reading materials that convey the atmosphere of the conference and the characteristics of famous scholars. We can also infer the nature of this book from the fact that the title and subtitle include the words "roundabout" and "story," respectively.

2.2 Chair Pauli's assault

Kamefuchi describes the chair Pauli's behavior as follows [1]: "He stood up, spoke in place of the speaker, behaved increasingly violent, and got so abusive as I have never heard in a physics conference." Some may wonder: Why did no participants protest the chair's behavior? The answer can be imagined from the following. Before the above description, Kamefuchi writes as follows: At the beginning, the chair Pauli, who was well known for his harshness, expressed the following introductory words, "I don't think there are any new ideas, but I'll open the session anyway."

Polkinghorne writes these Pauli's words in more detail and once again gives his personal opinion:

It would be of no use waving your hands in front of him and expressing the hope that it would all work out right in the end. ([4] p. 77)

At this point, Pauli already brought the entire audience to his knees, and no one could dare to advise him, who was famous for his effective spiciness.

References

1. S. Kamefuchi, Tosho No. 859, pp. 18–22 (2020).
2. W. Heisenberg, "Research on the non-linear spinor theory with indefinite metric in Hilbert space" in 1958 Annual International Conference on High Energy Physics at CERN, pp. 851–857 (CERN, Geneva, 1960).
3. Y. Katayama, "Space-time picture of elementary particles" in Proceedings of the 1967 International Conference on Particles and Fields, Ed. C. R. Hagen, G. Guralnik and V. A. Mathur (Interscience, New York, 1967) p. 157.
4. J. C. Polkinghorne, Rochester Roundabout: The Story of High Energy Physics, (W. H. Freeman, New York, 1989) p. 77.

(To be continued)
Serch word: Kamefuchi-2020

From Fujioka's Fluid Drop Model of Atoms to Einstein–Arakatsu Relationship

I have made a lot of exchanges with Bill Streifer (a researcher and freelance journalist on Intelligence, nuclear work and North Korea) at the Quora site from July 9 to 13, 2015. Most part of our exchanges is reproduced here by Bill's permission.

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Bill: Was Prof. Yoshio Fujioka's "fluid drop" model of the atom known as ekiteki?
And if so, why?

Tatsuo: I haven't learned about Yoshio Fujioka's "fluid drop" model of the atom but guess that if he proposed such a model, it should have been called "ekiteki" model. "Ekiteki" is the Japanese word for "fluid drop" (eki=fluid, teki=drop).

Bill: Prof. Ayao Kuwaki was a Japanese scientist and a friend of Albert Einstein. When did he die, exactly?

Tatsuo: According to the information page of him in "Wikipedia" (Japanese edition), Ayao Kuwaki was born on September 9, 1878, and died on May 16, 1945.

Bill: At the end of the war, an American airman met a man who claimed to be a student of Einstein in Germany. When I learned of Kuwaki, I suspected it might have been him. But now I see that's not possible since Kuwaki died in May 1945 and the "meeting" took place in September 1945.

Tatsuo: Sure, the student should not have been Kuwaki.

Bill: He might not have been a graduate student of Einstein, but he may have attended Einstein's lectures in Germany. Can you guess who he might have been? [And he lived in northern Korea in 1945!] An Einstein scholar is not willing to guess.

Tatsuo: I have no idea about that person.

Bill: If you provide a number of possibilities, I'll check each one. Did Hideki Yukawa study under Einstein?

Tatsuo: No, Yukawa didn't study under Einstein, but they met each other for the first time in Princeton on the former's return trip from Europe in 1939.

Bill: Einstein wasn't in Germany very long. I wonder if any Japanese or Korean scientists studied under Einstein when he taught there, or even attended his lectures.

Tatsuo: The Japanese physicist Jun (Atsushi) Ishiwara seems to have studied under Einstein in Germany (石原純 - Wikipedia). Ishiwara worked as an interpreter when Einstein visited Japan in 1922.

Bill: Thanks. Did Einstein have other Japanese students or followers in Germany? Kuwaki appears to be a little too old. I'm looking for a Japanese scientist who lived until 1946 at least.

Tatsuo: I don't think that Einstein had other Japanese students or followers in Germany.

Bill: I know of another.

Tatsuo: You Know? Who is he?

Bill: Dr. Bunsaku Arakatsu.

Tatsuo: Oh, Bunsaku Arakatsu was a teacher of my teacher and an experimental physicist. So, I didn't think he had studied under Einstein. Wikipedia page for him (Japanese edition) writes that he studied in Europe (Berlin, Zurich and Cambridge) for two years from 1926. It must have been a short time during this period that he studied under Einstein. By the way, his look is similar to Einstein's in some photos of him.

Bill: Can you find any photos of Einstein and Arakatsu together? If you can, please send them to photografr7@yahoo.com.
Is your teacher still alive? If so, could you ask him if Arakatsu or Yukawa visited Konan (Hungnam), Korea during the war? By the way, Konan and Hungnam are the same place, Konan is the Japanese pronunciation and Hungnam the Korean pronunciation.
You might also be interested in knowing that my article about an Austrian chemist who worked at Konan for more than two years (1935-1937 & 1940), will appear in a book being published by the University of Vienna Korean Dept. later this summer. The name of my article is A Letter from Korea.

Tatsuo: I don't have any photo of Arakatsu.
My teacher Kiichi Kimura at Physics Department, Kyoto University died in 1992. I haven't heard of Arakatsu's or Yukawa's visit to Hungnam (Konan), Korea. However, Arakatsu was associated with another Konan. Namely, he was the president of Konan University in Kobe, Japan, after his retirement from Kyoto University. Konan of Korea and Konan of the university in Kobe are different from each other when written in Chinese characters. The former Konan is written as 興南, and the latter, 甲南.
I have not so much interest in the history of science in Korea. However, if you write about some history of physics in Japan, I would like to read it very much.

Bill: I am familiar with Kimura. I am also aware that Konan, Japan is different than Konan, Korea.

Tatsuo: May I quote our exchanges made here these days in one of my blog sites written in English? Some friends of mine might be much interested in our exchanges.

Bill: Yes, that would be fantastic. And if anyone has any questions or comments, they can contact me directly at bill.streifer@gmail.com.

Tatsuo: Thanks a lot for your permission.

Bill: Stay in touch.

—A few days later we had additional exchange as given below.—

Bill: You can add this: According to page 15 of the book Uranium Matters: Central European Uranium in International Politics, 1900–1960 by Zbyněk A. B. Zeman and Rainer Karlsch, the Japanese physicist, Dr. Bunsaku Arakatsu "studied at Berlin University ... under Einstein, becoming a member of Einstein's close circle of friends."

Bill: I returned to the original document, and I am now convinced that the American airman met a Korean scientist, not a Japanese scientist in Korea in September 1945. But it's still interesting that Arakatsu was a close friend of Einstein, so all of this work wasn't for nothing.

Tatsuo: I've been on a trip to my hometown since Tuesday and am writing a belated reply. Thanks a lot for your additional information. We surely have gotten a good fruit.

(Last modified on July 29, 2015)

Yukawa's Utushi-e

When I read the English translation, by L. Brown and R. Yoshida, of Yukawa's autobiographical book Tabibito, I found many errors and sent a list of corrections to Brown. The list included shadow pictures as the translation of "うつしえ (utsushi-e)." Yukawa mentioned it together with ground-cherries and Kintaro wheat-gluten bars, etc. as things sold at street-stalls at a fair in his childhood. Utsushi-e meant both shadow pictures (写し絵) and transfer pictures (移し絵), but shadow pictures are played rather than sold. So, I thought the correct translation of utsushi-e should be transfer pictures but was not confident about this. In my childhood transfer pictures were surely popular among children. In the days when Yukawa was a child, however, sheets for shadow pictures (the equivalent to slides of the present days) might have been sold, and they might have enjoyed a picture show by passing lamplight through them. (This story was given in Part I, Chapter 1, of my book Passage through Spacetime.)

Recently I read Soseki's autobiographical novel Michikusa and found the following passage:

Of course, he was able to get whatever toys he wanted. Tools for utsushi-e (写し絵) were also included in it.

In Notes section at the end of Michikusa, the following description is given about utsushi-e:

The thing that reflects pictures drawn on glass onto a screen made of cloth or paper, in the dark; a magic lantern.

These indicate that the shadow picture was one of popular toys in Meiji period, to which childhood days of both Soseki and Yukawa belonged. Soseki was born in 1867; Yukawa, in 1907; and I in 1935. As for the year of birth, therefore, Yukawa and I are closer than Soseki and Yukawa. However, there was a big change of cultural environments when electric lights spread through the country [an almost full spread in Tokyo was achieved in 1912 (Ref. 1)]. In my childhood, I saw a projector of 8-mm film in a nearby home already being used instead of a magic lantern. Thus, Soseki and Yukawa had much in common in their childhood, and I have to admit that the translation, "shadow pictures," by Brown and Yoshida was quite right.

Reference

1. Chronology of electricity from Taisho to Showa, A Web page of the Federation of Electric Power Companies of Japan.

Classifications of Theoretical Physicists, Especially of Yukawa and Tomonaga

The theoretical physicist Susumu Kamefuchi published an essay entitled "Gramsci's words, Yukawa, Tomonaga, and Sakata" [1]. At the beginning of the essay, Kamefuchi quotes the following words:

Passage from knowing to understanding and to feeling and vice versa from feeling to understanding and to knowing —Antonio Gramsci, "Prison Notebooks" [2]

Kamefuchi likens the three elements in the above quotes, i.e., feeling, understanding and knowing to three stages of research in theoretical physics, i.e., (I) practitioner's stage, (II) theorist's stage and (III) natural philosopher's stage. Then, he thinks about the question in which stage each of Hideki Yukawa, Sin-Itiro Tomonaga, and Shoichi Sakata was good at working or liked to work, in order to classify them into corresponding three types, I, II and III, of physicists.

Sakata was called a person of methods and his successful studies, i.e., the two-meson theory and the Sakata model of elementary particles were phenomenological. From these facts, Kamefuchi classifies Sakata into type I.

Tomonaga had an excellent mastery of mathematics and expertise in constructing theories based on different physical requirements, producing the super‐many‐time theory, which lead him to the finding of the renormalization method and to the winning of Nobel Prize. Thus, Kamefuchi classifies him into type II.

Yukawa's work to create a comprehensive theory of particles starting from "nonlocal fields" or "elementary domains" corresponded to the process of going from knowing to understanding and to feeling, but was not completed. However, Yukawa said in his later year, "Such a fundamental theory was my ultimate purpose, and the meson theory was a byproduct on my way." Yukawa often presented his opinion about various cultural problems (creativity, genius, learning, peace, etc.), displaying his characteristic of being an excellent thinker in culture as well as in physics. From these facts, Kamefuchi classifies Yukawa into type III.

Kamefuchi's essay concludes as follows:

The fact that Yukawa, Tomonaga and Sakata belonged to the three different types was rather lucky to the development of particle theory in Japan. The three leaders played the role of antithesis against each other so that the study of particle physics in our country made a balanced progress. […] I believe that this was the basis of the Nobel-prize winning studies by the physicists of the next generation, Yoichiro Nambu, Masatoshi Koshiba, Toshihide Maskawa and Makoto Kobayashi.

Kamefuchi's classification scheme of physicists reminds me of a similar classification proposed by Yoichiro Nambu. His classification as summarized by himself is as follows [3]:

Once I classified theoretical physicists into three types according to their different styles of approach, and called them Heisenberg (H), Einstein (E) and Dirac (D) modes, referring to their most characteristic contributions respectively, i.e., quantum mechanics, theory of gravitation and the Dirac equation. Heisenberg’s is heuristic, bottom-up and inductive. Einstein’s is axiomatic, top-down and deductive. Dirac’s is abstract, revolutionary and esthetic.

As for the modes to which Yukawa and Tomonaga belongs, Nambu writes as follows [3]:

It would be safe to say that Yukawa belonged to H when he proposed the meson. He failed in E when he tried his hand at nonlocal theory. I have a bit of difficulty applying this to Tomonaga, but I will assign him to E. Most theorists belong to H or E. But, when it comes to contrasting Yukawa and Tomonaga, it may be appropriate to use the analogy to designer vs. craftsman.

Kamefuchi's type II and type III seem to correspond to Nambu's H mode and E mode, respectively. However, when we consider the corresponding categories identical, it causes inconsistency between Kamefuchi's and Nambu's classification of Yukawa and Tomonaga. The inconsistency comes from the difference in the viewpoint between Kamefuchi and Nambu. Namely, Kamefuchi attach importance on the physicist's preference of a method, especially for the classification of Yukawa, and Nambu, on the physicist's successful work.

On the other hand, Kamefuchi's type II and type III seem to correspond to Nambu's category of craftsman and that of designer, respectively. In this case, we can regard the corresponding categories as nearly equal without causing inconsistency between Kamefuchi's and Nambu's classification of the two physicists. The consistency in this case arises because Nambu's classification here is based on methodology of the physicists, similarly to Kamefuchi's.

References

1. S. Kamefuchi, Tosho No. 766, p. 2 (December, 2012) in Japanese.
2. English translation has been obtained from: Antonio Gramsci, Selections from the Prison Notebooks, edited and translated by Q. Hoare and G. N. Smith, p. 767 (ElecBook, London, 1999).
3. Y. Nambu, The Legacies of Yukawa and Tomonaga, AAPPS Bulletin Vol. 18, No. 6, p. 7 (2008)

Hideki Yukawa's Lindau Lecture

Reading a Scientific American article on the 61st Annual Lindau Nobel Laureate Meeting [1], I have learned the home page The Nobel Laureate Meeting at Lindau [2]. Scrolling the page downwards, we see a link to the Lectures Online page. There we can listen to more than 100 lectures of Nobel Laureates online. Among those lectures, I have found Hideki Yukawa's speech at the 3rd Lindau Nobel Laureate Meeting (1953, 1st Meeting in Physics) entitled "Attempt at a Unified Theory of Elementary Particles." Instead of the abstract of his presentation, a brief introduction is given by the editor Anders Bárány.

Bárány writes that Yukawa's full written lecture can be found in a special publication of the journal Naturwissenschaftliche Rundschau from 1981 and that the printed version contains a number of rather complicated equations not shown during his speech in Lindau. The Japanese version of the full written lecture appeared in November 1953 issue of Shizen and was reprinted in the special number for Yukawa memorial of the same journal published in November 1981.

Here are essential words from Bárány's introduction:

This was a time when one of the main problems in physics was the large number of elementary particles detected in cosmic rays and in high-energy accelerators. [. . . T]he problem was that, as Yukawa phrased it in his lecture, "Powell discovered a great number of extra particles which I did not need." Today we have the Standard Model of particles and forces, through which all the “extra” particles can be classified and all the forces computed. But we still miss what Yukawa was looking for in his attempt to formulate a unified theory of elementary particles [. . .]

Yukawa's attempt at that time was in the direction of nonlocal field theory.

There was a rumor that Yukawa's spoken English had the intonation of the Kyoto dialect. Listening to his Lindau lecture, I do not think so. His voice in this talk sounds young (he was 46 years old at that time) and fairly similar to the voice of his son, Taka'aki, whom we can listen to in the narration of the video The Yukawa Story [3]. I also think that Yukawa's talk in English is more listenable than his lecture in Japanese at the classroom of the university.

I owe to Mr. M. M. for the information of the Japanese version of Yukawa's written Lindau lecture.

1. S. Mirsky, Noble Nobel faces: A week in Lindau, where scientists are celebrities. Scientific American (September 1, 2011); printed version, September issue, page 78 (2011).
2. The Nobel Laureate Meeting at Lindau: Educating, Inspiring, Connecting scientific Generations since 1951, www.lindau-nobel.org.
3. The Yukawa story, You Tube video (uploaded on December 23, 2009).

Hideki Yukawa's Words about Nuclear Power Development -3-

Among the three essays of Yukawa on nuclear energy, the last one, "Nuclear power in Japan: Haste makes waste," was written in the year of Yukawa's resignation from the (Japan) Atomic Energy Commission (JAEC). That essay begins with the following sentence:

Last year (1956) "the Atomic Energy Basic Law" was enacted, and the Atomic Energy Commission was established. Then, a number of significant changes happened to the domestic as well as international situations about nuclear energy.

The significant changes meant in the above quote can be seen in Ref. 1 as follows (partial omissions are made in the quote):

Being triggered by the first Atoms for Peace Conference held in August previous year, nuclear boom arrived. On January 1, "the Atomic Energy Basic Law" was established, and the JAEC started [as described by Yukawa]. Matsutaro Shoriki was appointed the first chairman of the JAEC. Atomic Energy Bureau was also inaugurated under Prime Minister's Office. Japan Atomic Energy Research Institute (JAERI; presently, Japan Atomic Energy Agency) and Nuclear Fuel Corporation were launched in May and August. On the other hand, an industry group established Japan Atomic Industrial Forum (presently, Japan Atomic Industrial Association) in March. The followings happened overseas: The No. 1 reactor of the Calder Hall nuclear power station in Britain started the sending of power in May, and the General Assembly of United Nations adopted the Charter of the International Atomic Energy Agency on October 23.

These are truly high-flying moves. Furthermore, we find the followings in the nuclear chronology of that year in Japan [Ref. 1]: On January 13, the JAEC Chairman M. Shoriki released the inaugural statement, including the plan of the earliest importing of research reactors from the US to strengthen the system for the development of nuclear energy. On the same day, the Cabinet decided the importing of water-boiler and CP-5 types research reactors from the US. On February 10, JAERI was permitted to import, from the US, four tons each of natural uranium and heavy water for research. On March 23, the JAEC determined the basic outline of the development and utilization of nuclear power and suggested the development of breeder reactors. On March 27, JAERI made the covenant of importing a water-boiler type nuclear reactor from North American Airlines in the US. — These led to Yukawa's expression of intention to resignate from the JAEC on April 24 (the date of actual resignation is March 29, 1957).

In the third essay on nuclear energy, Yukawa first claims the following about the use of isotopes, i.e., the use of nuclear energy in a broad sense:

[. . .] the problems of preventing danger and controlling conditions for health will become important. We have to make every effort to solve these problems.

Then, Yukawa enters into the issue of nuclear power generation and points out as follows:

The next stage should be the one in which researchers and technicians in our country have to show more creativity and autonomy. For this purpose, it is necessary at least to go through the steps of domestic designing and manufacturing of reactors, production of fuel, establishing the method of spent fuel disposal, etc.

The national movement in history was quite contrary to the steps Yukawa thought to be necessary.

Yukawa further writes,

It is clear that we are no longer allowed to leave the issue of nuclear power indefinitely on the desk.

While the above view is the one pressed by the situation, he sharply criticizes Japan's nuclear policy as follows:

Because such a sudden change of the situation is also expected to occur in the future, hastening should be avoided concerning power reactors. It would be quite uncomfortable that, while some people are making preparations for raising seedlings, the other people suddenly appear with cut flowers from a shop.

In the last paragraph of the essay, Yukawa gives the following warning:

In the Western world, there is a saying, "Make haste slowly." In Japan we also have the proverb, "Haste makes waste."* With respect to nuclear power, these words fit quite well to the point. [. . .] At the same time, we have to think about nuclear weapons, which is the largest obstacle to the peaceful use of nuclear energy. We Japanese should make every effort more intensely than before to eliminate them from all over the world as soon as possible, on this occasion of our country's having joined the United Nations.

The following was reported recently [Ref. 2]:

An official's testimony has made this clear: Forty years ago, Fukushima Daiichi nuclear power plant of Tokyo Electric Power Company prepared emergency power generators in the basement by adopting "the American design," which had been developed against hurricanes and tornadoes, and this made accidents extremely large. The underground of the power plant was entirely soaked in water by the tsunami more than 10 meters high and lost all electric power sources at once.

Japan's policy immediately to import nuclear reactors without considering Yukawa's warnings has led to the disastrous accidents of Fukushima Daiichi nuclear power plant, producing a lot of radioactive waste just as was told by the proverb. Reflecting their own responsibility fully, all the Japanese should pave the way for the complete abolition of nuclear power plants in our country and the comprehensive elimination of nuclear weapons from the world over. (End)

* Note by the present author: The Japanese proverb is literally translated as "When in haste, take the roundabout way." However, this is too long to be used as the translation of the subtitle of Yukawa's essay, so that it has been replaced by another saying in English of the same meaning.

1. Nuclear Chronology: 1956, Web site of Research Organization for Information Science & Technology, in Japanese.
2. Wrong adoption of "American design" for nuclear reactors: Generators in the basement against hurricanes, Asahi Shimbun, Evening edition (June 11, 2011) in Japanese.

Hideki Yukawa's Words about Nuclear Power Development -2-

Hideki Yukawa's Auto-Collected Writings Vol. 3 [Ref. 1] includes the following three essays about nuclear power:

(1) Atomic energy and humanity's turning point -1954 -, p. 261.
(2) The nuclear issue and the true nature of science -1954 -, p. 265.
(3) Nuclear power in Japan: Haste makes waste -1957 -, p. 269.

In essay (1), Yukawa writes that we have entered such a period in which each of us has to think about the tight relationship among the fates of people in different countries and has to pay far greater efforts than ever in order to save mankind from the threat of nuclear weapons. He also describes his own belief that he has to think about it more seriously as a scientist and that he stands at closer to this problem as one of the Japanese, than other persons. In spite of the presence of the words "atomic energy" in the title, this essay does not yet refer to the problems of nuclear reactors.

In essay (2), Yukawa writes first, "Since the beginning of March this year, nuclear issues have become more familiar than before to grow up to the subject of intense interest of the general public." Then, he explains the differences between the basic studies of atomic physics (nuclear and particle physics in the present terminology) and studies of nuclear science application.

As for March 1954, we have to remember the following things: On the sixteenth, it was revealed by Yomiuri Shimbun that the Japanese tuna fishing boat, Daigo Fukuryū Maru, had been exposed to fallout from the United States' thermonuclear device (H-bomb) test on Bikini Atoll (it happened on March 1); and on the twenty-second, the Operations Coordinating Board (OCB), established under the US National Security Council (NSC), proposed to provide experimental nuclear reactor to Japan, which became the beginning of the US plans to suppress anti-nuclear movements in Japan caused by the anger against A- and H-bomb sufferings [Ref. 2]. Earlier than this, three conservative parties of Japan submitted a proposal to the Diet on March 2. It was a 250 million yen budget for nuclear reactors and was passed without discussion on April 3.

On the other hand, on March 18, 1954, the Special Committee of Nuclear Science under the Science Council of Japan decided to keep the three principles of independence, democracy and openness in nuclear science research. On April 23, the Science Council of Japan condemned the Government's approach to nuclear reactors and issued a statement about the refusal of nuclear weapons research and complying with the three principles aforementioned [Ref. 3].

The words of "nuclear reactors" does not yet appear in Yukawa's essay (2), but the following passage is included at its end:

[…] as the research develops to extend its applications, a significant and unintended impact on human life happens to appear at the outside of the original purpose. As a scientist and as one of human beings, I repeat many times to reflect this: Which would the application of science produce, the result to which humans are grateful or the opposite result that threatens humanity? Which would the branching point of the main road of science lead to, the road to hell or the road to heaven?

The two kinds of results and the two roads described in the above passage might have come to Yukawa's attention from the thought about A- and H-bombs. However, he pointed out the truth that a dreadful result always has a possibility to occur ahead of "the branching point." Looking back on those words of his, we find that Yukawa even predicted the disasters at Fukushima Daiichi nuclear power plant. (To be continued.)

References

1. H. Yukawa, Auto-Collected Writings, Vol. 3 (Asahi Shimbun, 1971).
2. US–Japan relations and the headwaters of nuclear power plants (4), Shimbun Akahata (June 10, 2011) in Japanese.
3. Nuclear Chronology: 1954, Web site of Research Organization for Information Science & Technology.

Hideki Yukawa's Words about Nuclear Power Development -1-

The decisions of any kind regarding agreements about or implementation of power reactors will surely have an important impact on the future of long-term nuclear power development in Japan. Accordingly, we should be much cautious about it. — Hideki Yukawa, Atomic Energy Commission Monthly Report, January issue (1957) in Japanese.

In January 1956, Matsutaro Shoriki, the first chairman of the Atomic Energy Commission, released The plan for the construction of nuclear power plants in five years and conclusion of the atomic-power agreement with United States. At the end of that year, the Japan–United States Atomic Agreement, which had guaranteed the independent nuclear research in Japan, began to be reviewed for revision. Hideki Yukawa resigned the Atomic Energy Commission in protest against this. Thereafter, the Atomic Energy Commission was dominated by the Government of Liberal Democratic Party, and was transformed to the agency of promoting nuclear-reactor construction. Yukawa's words quoted above represent the accusation against such a situation just before his resignation. [The above description is based on: US–Japan relations and the headwaters of nuclear power plants (4), Shimbun Akahata (June 10, 2011) in Japanese].

It is deeply regrettable that the absence, in the Atomic Energy Commission, of scientists who took over Yukawa's spirit of protest was one of the factors leading to the nuclear accidents in Fukushima.

The Mystery of Yukawa's "New Insight" (Second Revision)

Hideki Yukawa described the climax of the development of his meson theory in his autobiography Tabibito [1]. However, this description is contradictory to the record of his academic presentation made more than a year before the date of climax. Study on this problem has revealed that two factors were responsible to this contradiction.

Yukawa's passage we treat is the following:

The crucial point came to me one night in October. The nuclear force is effective at extremely small distances, on the order of 0.02 trillionth of a centimeter. That much I knew already. My new insight was the realization that this distance and the mass of the new particle that I was seeking are inversely related to each other. Why had I not noticed that before?

"October" in this quote means that of 1934 according to the paragraph that precedes it. Note that his new insight means the realization of the inverse proportionality of the effective distance of the nuclear force (the force that binds neutrons and protons in the nuclei) to the mass of the new particle that mediates this force. Hereafter, we call this inverse proportionality distance-mass relation.

On the other hand, Yukawa made his first oral presentation at a meeting of the Physico-Mathematical Society of Japan held in Sendai in April, 1933. The title of the presentation was "A consideration about the problem of electrons within nuclei," and its abstract includes the following sentence [2]:

From the fact that the electron has the rest mass, we consider that the strength of the interaction decreases rapidly, as the distance between the neutron and the proton becomes large compared with h/(2πmc).

Here, we find that Yukawa used the distance-mass relation already in 1933. Thus, it is contradictory to call the realization in 1934 of this relation "my new insight".

We guess that the following two factors were responsible to the above contradiction.

1. Hisao Sawano of the Assahi Shimbun Company helped the publication of the Japanese version* of Tabibito by editing Yukawa's manuscript [3]. If Sawano's editing had been to such an extent as to change Yukawa's original version into more dramatic one here and there, then Sawano must have modified the passage about the climax without thinking that his change might contradict Yukawa's academic record.

2. In the work of his 1933 presentation, Yukawa treated the possibility that the electron might be the mediator of the nuclear force. This hypothesis included difficulties related to the spin and statistics of the electron. Therefore, Yukawa abandoned the hypothesis soon later. At the same time, he might also have discarded the distance-mass relation. If so, Yukawa had to rediscover it for completing the paper on the meson theory.

There are two accounts that support factor 1. One of them is Yukawa's passage in Ref. 4. He describes there that he finished writing the last section related to the discovery of the meson theory just a few hours before his trip to Europe. Perhaps, Yukawa regularly checked the changes made by Sawano in order for those not to be contradictory to facts. As for the last section, however, it is quite possible that Yukawa's trip to Europe made such a check impossible.

The other account is in the autobiographical book** [5] of Hideki Yukawa's wife, Sumi. She wrote about the days of their visit to Stockholm for Hideki's receiving Nobel Prize. On arriving at a hotel there, they found that many journalists were waiting to interview Hideki. Sumi's passage about part of the interview is as follows:

One of the questions addressed to him was this: "We hear that the Japanese people study sitting on their legs in a straw-matted room. Did you, Dr. Yukawa, write your paper sitting on your legs or sitting on a chair at the Western-style desk?" Hideki thought a little while and said, "I did in neither of those ways. I put my thoughts together at night in bed." This is true. Hideki wrote the paper that brought him Nobel Prize after he had kept thinking many nights at the age of 27 in the year of Shōwa 9 [Note by the translator: 1934]. This story seems to have wrongly come across to Japan. Thus, in Japan they believe that the idea flashed to him in the middle of a night.

This passage makes us think that the description in Ref. 1 about the sudden coming of the crucial point one night was a modification by Sawano, because it resembles the wrong information conveyed from Sweden to Japan. Further, we can consider that Sumi here denied the modified description indirectly. However, we should note Sumi's possible denial refers, in a strict sense, only to "that the idea flashed to him in the middle of a night." This is not relevant to the essential point of the contradiction, because what is contradictory is the content of the "new insight." This content is highly technical and possibly beyond Sawano's ability of rewriting. Therefore, factor 1 alone cannot be the cause of the contradiction.

With regard to factor 2, we find a strong support for this in Ref. 6, where Kawabe and Konuma write as follows:

In the manuscript of the presentation of April 1933, Yukawa corrected his idea in the abstract to read "the actual calculation does not yield this result." Further, in the draft "Bose electron theory" written almost at the same time as the above manuscript (it had been preserved in the file "Manuscripts of seminars and colloquia, 1934–1935"), he wrote, ". . . the term including the Compton wavelength of the electron appears as a kind of phase factor, . . . and, as a consequence, we cannot say the force decreases rapidly with increasing distance."

The above quote clearly shows that Yukawa once fully discarded the distance-mass relation and that the rediscovery of it was necessary.

The words "My new insight" in the quote from Ref. 1 is not the literal translation of the original words. The literal translation of the relevant passage would be as follows:

One night in early October, a thought flashed through my mind. The nuclear force has only an extremely short effective range. It is on the order of 0.02 trillionth of a centimeter. This has been known since earlier time. What I noticed is that this effective range and the mass of the new particle that accompanies the nuclear force would be inversely proportional to each other. Why did I not notice such a thing until then?

If we omit the last sentence in the above passage,*** the thought that flashed Yukawa's mind does not necessarily mean to be new; it can be the revival or the rediscovery of an earlier thought. Thus, the first and the last sentences in the Yukawa's original manuscript, before Sawano's modification, might have been:

In early October, a thought came to my mind. . . . Why did I not examine this again until then?

Then, the passage is a less dramatic depiction of the development of the meson theory but does not contradict to his earlier use of the distance-mass relation. Hideki Yukawa's own autobiography was translated into English, French and German. Therefore, the wrong version of the story modified by Sawano has become famous world over. This is unfortunate. Sumi Yukawa's account quoted above should be informed widely.

(This article owes much to the discussion we have had at Osaka Science Museum among the members of "Citizens' Study Group on Hideki Yukawa.")

Notes

* The Japanese version of Tabibito first appeared as a series of 112 stories in Asahi Shimbun from March to July, 1958.

** The title Kuraku-no-Sono was taken from the street name in Nishinomiya City, where Hideki and Sumi Yukawa lived in the years shortly after their marriage. It has the meaning of "the garden (sono) of joys and sorrows (kuraku)."

*** See also the same passage in the German version [7]: Eines Abends Anfang Oktober hatte ich mit einem Mal die richitige Idee. Die Kernkraft hat eine äußerst kurze Reichweite: nur 2/10-billionstel Zentimeter. Das wußte ich schon vorher. Was ich nun bemerkte, war vielmehr, daß die Reichweite und die Masse der zur Kernkraft gehörenden neuen Teilchen zueinander in umgekehrter Proportion stehen müßen. Warum war ich nicht schon eher darauf gekommen!

References

1. H. Yukawa, Tabibito (The Traveler), translated by L. Brown and R. Yoshida (World Scientific, 1982) p. 202.
2. H. Yukawa, Sūbutu-gakkaisi, Vol. 7, No. 2 (1933) quoted in Nihon-no Buturigaku-shi (History of Physics in Japan) (Tokai University Press, 1978) p. 319 (in Japanese; English translation of the quoted passage by the present author).
3. H. Yukawa, Atogaki (Afterwords) in Tabibito, (Kadokawa, 1960) (in Japanese).
4. H. Yukawa, Hon-no Naka-no Sekai (The World in Books) (Iwanami, 1963) p. 182 (in Japanese).
5. S. Yukawa, Kuraku-no-Sono (Kōdansha, Tokyo, 1976) pp. 349–350 (in Japanese; English translation of the quoted passage by the present author).
6. M. Kawabe and M. Konuma, Butsuri Vol. 37, p. 265 (1982) (in Japanese).
7. Hideki Yukawa: Tabibito - Ein Wanderer, Grosse Naturforscher Band 48, ed. Erwin Müller-Hartmann, transl. Claus M. Fischer, p. 175 (Wissenschaftliche Verlagsgesellschaft, Stuttgart, 1985).

The Mystery of Yukawa's "New Insight" (Revised)

Please read the Second Revision instead of this article, which is retained only as the record of the processes of my solving the mystery.

The crucial point in the development of Hideki Yukawa's meson theory came to him one night in October 1934. He writes in his autobiography Tabibito [1] as follows:

My new insight was the realization that this distance [the effective range of the nuclear force] and the mass of the new particle that I was seeking are inversely related to each other. Why had I not noticed that before?

This passage contradicts the fact that Yukawa used the above relation already in 1933. Namely, in April that year he made his first oral presentation at a meeting of an academic society. It was entitled "A consideration about the problem of electrons within nuclei," and the meeting was the one held in Sendai by Physico-Mathematical Society of Japan. The abstract of the presentation includes the following sentence [2]:

From the fact that the electron has the rest mass, we consider that the strength of the interaction decreases rapidly as the distance between the neutron and the proton becomes large compared with h/(2πmc).

In the work of the above presentation, Yukawa treated the possibility that the electron might be the mediator of the nuclear force between the neutron and the proton. This hypothesis included difficulties related to the spin and statistics of the electron. Therefore, Yukawa totally abandoned the hypothesis later together with the relation of the distance and the mass of the particle that would mediate the nuclear force [3]. Did this abandonment make it necessary for Yukawa to rediscover the relation? If so, this explains the contradictory remark of his "new insight."

We find another possible explanation of the contradictory description in the process of the making of Yukawa's autobiography. Hisao Sawano of the Assahi Shimbun Company helped the publication by editing Yukawa's manuscript [4]. If Sawano's editing had been to such an extent as to change Yukawa's original version into more dramatic one here and there, the passage that began with "My new insight" might have been Sawano's modification. To eliminate the expression different from the fact, Yukawa, perhaps, regularly checked the changes made by Sawano. However, Yukawa finished writing the last section related to the discovery of the meson theory just a few hours before his trip to Europe [5]. Thus, it is quite possible that Yukawa did not check Sawano's modification of that section.

Both Yukawa and Sawano are now in heaven. Thus, the mystery of the "new insight," i.e., which of the above two explanations was the case, does not seem to be solved easily. However, we have another clue to solve this problem.

In her autobiographical book* [6], Hideki Yukawa's wife, Sumi, wrote about the days of their visit to Stockholm for Hideki's receiving Nobel Prize. On arriving at a hotel there, they found that many journalists were waiting to interview Hideki. Sumi's passage about part of the interview is as follows:

One of the questions addressed to him was this: "We hear that the Japanese people study sitting on their legs in a straw-matted room. Did you, Dr. Yukawa, write your paper sitting on your legs or sitting on a chair at the Western-style desk?" Hideki thought a little while and said, "I did in neither of those ways. I put my thoughts together at night in bed." This is true. Hideki wrote the paper that brought him Nobel Prize after he had kept thinking many nights at the age of 27 in the year of Shōwa 9 [Note by the translator: 1934]. This story seems to have wrongly come across to Japan. Thus, in Japan they believe that the idea flashed to him in the middle of a night. [Translated by T.T. from Japanese.]

Here Sumi clearly denies the story in Ref. 1 of the "new insight" that came suddenly. Therefore, the second possibility given above, i.e., the contradiction is due to Sawano's modification, should be regarded as the case.

Hideki Yukawa's own autobiography was translated into English, French and German. Therefore, the wrong version of the story modified by Sawano has become famous world over. This is unfortunate. Sumi Yukawa's account quoted above should be informed widely.

(This article owes much to the discussion we have had at Osaka Science Museum among the members of "Citizens' Study Group on Hideki Yukawa.")

Note

* The title Kuraku-no-Sono was taken from the street name in Nishinomiya City, where Hideki and Sumi Yukawa lived in the years shortly after their marriage. It has the meaning of "the garden (sono) of joys and sorrows (kuraku)."

References

1. H. Yukawa, Tabibito (The Traveler), translated by L. Brown and R. Yoshida (World Scientific, 1982) p. 202.
2. H. Yukawa, Sūbutu-gakkaisi, Vol. 7, No. 2 (1933) quoted in Nihon-no Buturigaku-shi (History of Physics in Japan) (Tokai University Press, 1978) p. 319 (in Japanese; English translation of the quoted passage by the present author).
3. M. Kawabe and M. Konuma, Butsuri Vol. 37, p. 265 (1982) (in Japanese).
4. H. Yukawa, Atogaki (Afterwords) in Tabibito, (Kadokawa, 1960) (in Japanese).
5. H. Yukawa, Hon-no Naka-no Sekai (The World in Books) (Iwanami, 1963) p. 182 (in Japanese).
6. S. Yukawa, Kuraku-no-Sono (Kōdansha, Tokyo, 1976) pp. 349–350 (in Japanese).

The Solution to the Mystery of Yukawa's "New Insight"

Previously I wrote the article [1] that can be summarized as follows:

According to his autobiography [2], Yukawa arrived at a crucial point in the development of his meson theory one night in October 1934 by getting a "new insight." It was about the relation between the effective range of the nuclear force and the mass of the new particle he was seeking. However, this contradicts the fact that he used this relation already in 1933. There are two possibilities to explain the contradiction: (1) Yukawa once thoroughly abandoned the idea in which he used the relation, so that he had to rediscover it. (2) The description in Ref. 2 is the change made by Hisao Sawano of the Asahi Shimbun Company, who helped the publication of the autobiography by editing Yukawa's manuscript. Both Yukawa and Sawano passed, and the mystery of the "new insight," i.e., which of the above two explanations was the case, cannot be solved easily.

Reading the autobiographical book* [3] written by Hideki Yukawa's wife, Sumi, I have found a clue to solve the above mystery. Sumi wrote about the days of their visit to Stockholm for Hideki's receiving Nobel Prize. On arriving at a hotel there, they found that many journalists were waiting to interview Hideki. Sumi writes as follows:

One of the questions addressed to him was this: "We hear that the Japanese people study sitting on their legs in a straw-matted room. Did you, Dr. Yukawa, write your paper sitting on your legs or sitting on a chair at the Western-style desk?" Hideki thought a little while and said, "I did in neither of those ways. I put my thoughts together at night in bed." This is true. Hideki wrote the paper that brought him Nobel Prize after he had kept thinking many nights at the age of 27 in the year of Shōwa 9 [Note by T.T.; 1934]. This story seems to have wrongly come across to Japan. Thus, in Japan they believe that the idea flashed to him in the middle of a night. [Translated by T.T. from Japanese.]

This passage by Sumi clearly denies the story in Ref. 2 of the "new insight" that came suddenly. Therefore, the possibility (2) given above should be regarded as the case.

Hideki Yukawa's own autobiography was translated into English, French and German. Therefore, the wrong version of the story modified by Sawano, "The crucial point came to me one night in October. … My new insight was …" has become famous world over. This is unfortunate. Sumi Yukawa's account quoted above should be informed widely.

Note

* The title Kuraku-no-Sono was taken from the street name in Nishinomiya City, where Hideki and Sumi Yukawa lived in the years shortly after their marriage. It has the meaning of "the garden (sono) of joys and sorrows (kuraku)."

References

1. The Mystery of Yukawa's "New Insight," Ted's Coffeehouse (February 27, 2010).
2. H. Yukawa, Tabibito (The Traveler), translated by L. Brown and R. Yoshida (World Scientific, 1982) p. 202.
3. S. Yukawa, Kuraku-no-Sono (Kōdansha, Tokyo, 1976) in Japanese.

Rivals

At the Vancouver Winter Olympics, Yu-na Kim of South Korea took the gold medal of women's figure skating competition with a world record score; and Mao Asada of Japan, the silver. Both of them played beautifully and are only 19 years old. Further, they have been rivals each other since quite young days. Thus, their rivalry will perhaps continue through coming years. This reminds me of the relationship between Hideki Yukawa and Shi'nichiro Tomonaga.

Before his publishing of the paper on the meson theory, Yukawa had the days of slowdown in his research at the Department of Physics, Osaka University. Then Hidetsugu Yagi, the then Head of the Department and known by Yagi antenna, said to him, "We had the plan of recruiting Tomonaga but your brother's request compelled us to adopt you. Therefore, we should be in trouble if you do not work harder than Tomonaga." These words stimulated Yukawa soon to complete the research on the prediction of the existence of the meson (this story has been translated and adapted from [1]). He got Nobel Prize in Physics for that work in 1949. Tomonaga shared the same award in 1965 with Julian Schwinger and Richard Feynman for their work in quantum electrodynamics.

I also had some rivals in studying during my schoolboy days. They were mostly girls. Among them, one has been the enduring rival, though our specialties have been quite different. She studied Japanese literature in Edo period and is now Professor Emeritus of the University of California, Santa Barbara, while I am a little proud of publications in many different academic journals ranging from physics to psychology. I rarely meet her or exchange messages with her but am grateful to her for continued rivalry.

(Noticing of [1] owes to the discussion we have had at Osaka Science Museum among the members of "Citizens' Study Group on Hideki Yukawa.")

Note added later: Mao Asada beat Kim Yu-na to win her second title at the World Figure Skating Championships held in Turin, Italy, on March 27, 2010.

1. R. Utiyama's writing, quoted in: "Light" into after-war darkness, Asahi Shimbun, special pages for its 120th anniversary (February 13, 1999) in Japanese.

The Mystery of Yukawa's "New Insight"

Please read the revised version instead of this article:
The Mystery of Yukawa's "New Insight" (Revised).

Read in Japanese.
(The Japanese version has not yet been revised.)

The crucial point in the development of Hideki Yukawa's meson theory came to him one night in October 1934. He writes in his autobiography Tabibito [1] as follows:

My new insight was the realization that this distance [the effective range of the nuclear force] and the mass of the new particle that I was seeking are inversely related to each other. Why had I not noticed that before?

This passage contradicts the fact that Yukawa used the above relation already in 1933. Namely, in April that year he made his first oral presentation at a meeting of an academic society. It was entitled "A consideration about the problem of electrons within nuclei," and the meeting was the one held in Sendai by Physico-Mathematical Society of Japan. The abstract of the presentation includes the following sentence [2]:

From the fact that the electron has the rest mass, we consider that the strength of the interaction decreases rapidly as the distance between the neutron and the proton becomes large compared with h/(2πmc).

In the work of the above presentation, Yukawa treated the possibility that the electron might be the mediator of the nuclear force between the neutron and the proton. This hypothesis included difficulties related to the spin and statistics of the electron. Therefore, Yukawa totally abandoned the hypothesis later together with the relation of the distance and the mass of the particle that would mediate the nuclear force [3]. Did this abandonment make it necessary for Yukawa to rediscover the relation? If so, this explains the contradictory remark of his "new insight."

We find another possible explanation of the contradictory description in the process of the making of Yukawa's autobiography. Hisao Sawano of the Asahi Shimbun Company helped the publication by editing Yukawa's manuscript [4]. If Sawano's editing had been to such an extent as to change Yukawa's original version into more dramatic one here and there, the passage that began with "My new insight" might have been Sawano's creation. To eliminate the expression different from the fact, Yukawa, perhaps, regularly checked the changes made by Sawano. However, Yukawa finished writing the last section related to the discovery of the meson theory just a few hours before his trip to Europe [5]. Thus, it is quite possible that Yukawa did not check Sawano's modification of that section.

Both Yukawa and Sawano are now in heaven, and the mystery of the "new insight," i.e., which of the above two explanations was the case, cannot be solved easily.

(This article owes much to the discussion we have had at Osaka Science Museum among the members of "Citizens' Study Group on Hideki Yukawa.")

Read the continuation of this article: The Solution to the Mystery of Yukawa's "New Insight"

1. H. Yukawa, Tabibito (The Traveler), translated by L. Brown and R. Yoshida (World Scientific, 1982) p. 202.
2. H. Yukawa, Sūbutu-gakkaisi, Vol. 7, No. 2 (1933) quoted in Nihon-no Buturigaku-shi (History of Physics in Japan) (Tokai University Press, 1978) p. 319 (in Japanese; English translation of the quoted passage by the present author).
3. M. Kawabe and M. Konuma, Butsuri Vol. 37, p. 265 (1982) (in Japanese).
4. H. Yukawa, Atogaki (Afterwords) in Tabibito, (Kadokawa, 1960) (in Japanese).
5. H. Yukawa, Hon-no Naka-no Sekai (The World in Books) (Iwanami, 1963) p. 182 (in Japanese).

Effects of Chinese Classic Literature on H. Yukawa's Work

The following is the outline of my talk to be delivered at Himeji Kyoyukai meeting on February 18, 2010, in Himeji.

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The Nobel-winning physicist Hideki Yukawa developed the theory of elementary domains for particle physics together with his coworkers in his later years [1, 2]. In the preface of a book [3], he writes that the important factor that led him to the idea of this theory was the words of the Chinese poet Li Po (701­­–762), "Heaven and Earth are hotels for everything, and days and nights are travelers of hundreds of generations." He also writes that scientific research and literature are not separate things for him.

Yukawa also writes in a textbook on particle physics [4] that Li Po's words mentioned above was one of the motivations that brought his unconscious idea about the elementary domains to his consciousness. While being rather lengthy for introducing the concept of the elementary domains in a textbook, the paragraphs including the above words are considered the valuable record of Yukawa's processes of thinking.

In his lecture on experimental nuclear physics, Kiichi Kimura, a classmate of Yukawa's at Kyoto University, told us that some words in the Taoist book Zhuangzi might have been a hint on Yukawa's meson theory that brought him the Nobel Prize. I do not remember the words Kimura quoted from Zhuangzi. In his 1961 essay [5] on Zhuangzi, however, Yukawa writes that he had read Taoist books Zhuangzi and Laozi in his middle school days, but was forgetting philosophical thoughts in them for many years after that. This means: When he was thinking about meson theory, Yukawa was forgetting Zhuangzi. Thus, the words of Zhuangzi Kimura mentioned had not been a direct hint, at least, on the idea of the meson.

It was reported [6] that the meson theory had been motivated by the occasion of the childbirth of Yukawa's wife. Namely, the judo expert Sachio Ashida remembered to have been told in a commuting tramcar by Yukawa, "A baby can exert an attractive force between the parents. There may be a similar existence in the nucleus." I suppose that this was Yukawa's jocular explanation of his idea for the layperson. Yukawa should have gotten the idea of the meson from the study of earlier papers by Werner Heisenberg and Enrico Fermi together with the analogy of the electromagnetic field mediated by the photon. Note here that he used a good analogy.

In his essay mentioned above [5], Yukawa writes that he reminded himself of an allegory in Zhuangzi when he was thinking about something at a deeper level than "elementary particles," which amounted to more than 30 kinds those days. The allegory was about the king who lacked all the seven holes in the face, i.e., ears, eyes, nostrils and a mouth, and was named Chaos ("Konton" in Japanese). The underdeveloped state of the king was appropriate for Yukawa to express his idea of something at a deeper level.

Yukawa also liked the following words from Zhuangzi: "On the basis of the beauty of Heaven and Earth, we arrive at the reason of everything." He made these words in Chinese characters use as a watermark of the invitation letter for "International Meeting on Elementary Particles: The Thirtieth Anniversary of the Meson Theory" [7].

To develop a new theory in the field of particle physics, it is necessary to have good mathematical skill of formulating equations to express a physical model, as well as strong imaginative power to think of a new model. One of the important device with which Yukawa cultivated the latter ability should have been Chinese classic literature, which includes a lot of allegories and helps one to develop thinking by the use of an analogy. Thus his reading of Chinese classic literatures in his young days was useful not only directly for the idea of elementary domains, but, quite possibly, also indirectly for the idea of the meson.

(This article owes much to the discussion we have had at Osaka Science Museum among the members of "Citizens' Study Group on Hideki Yukawa.")

References

1. Y. Katayama and H. Yukawa, "Field Theory of Elementary Domains and Particles. I" Progress of Theoretical Physics Supplement No. 41, p. 1 (1968).
2. Y. Katayama, I. Umemura and H. Yukawa, "Field Theory of Elementary Domains and Particles. II" ibid. p. 22 (1968).
3. H. Yukawa, Auto-selection of Hideki Yukawa's Essays Vol. 5 (Asahi-shimbun, Tokyo, 1971) [in Japanese].
4. H. Yukawa, Unified Theories of Particles, in Iwanami Lectures: Foundations of Modern Physics, Vol. 11, H. Yukawa and Y. Katayama, ed., p. 563 (Iwanami, Tokyo, 1974) [in Japanese].
5. H. Yukawa, Zhuangzi, in Auto-selection of Hideki Yukawa's Essays Vol. 3, p. 363 (Asahi-shimbun, Tokyo, 1971) [in Japanese].
6. Personal connections in Japan: The spirit of Judo (8), Asahi-shimbun, Evening issue (May 25, 2006) [in Japanese].
7. The 30th anniversary of Meson theory (1), Asahi-shimbun (September 20, 1965) [in Japanese].