Richard Phillip Feynman speaking at the
Spring Meeting of the American Physical Society (Washington, DC, USA, 1970)

I took this photo with my Canon camera with a 135mm telephoto lens without flash. The lecture room was dark. You cannot see Feynman's black hair because the background was dark.

• In 1970, the April meeting of the American Physical Society was held at Washington's Shoreham Hotel. There was a Nobel session in which five Nobel Laureates gave their talks. All were dressed neatly, except Feynman. He was without coat and necktie as you can see from this photo.

• What Feynman said in his lecture was also stunning. He was talking about the use of harmonic oscillator wave functions for relativistic quark model, and the content of his talk was published in Phys. Rev. [Feynman, Kislinger, and Ravndal, Phys. Rev. D 3 , 2706 (1971)]. He told us not to use Feynman diagrams but use oscillator wave functions for relativistic bound states.

  I liked his talk very much and I was even excited, but most of my colleagues thought Feynman was absolutely crazy. Furthermore, it is generally agreed that the above-mentioned Phys. Rev. paper gets a failing grade from the mathematical point of view.

• In spite of all these, I am very proud to say that what Feynman said at the 1970 meeting became the starting point of my research program. This is perhaps the reason why many of my colleagues are saying I am crazy. I started my program by making up the mathematical shortcomings in his 1971 paper. Thanks to Eugene Wigner, I knew how to use the Poincaré group, and started constructing normalizable covariant harmonic oscillator wave functions. I started publishing papers on this subject in 1973 with Marilyn Noz. She has been and still is my most valuable co-author.

  Those covariant wave functions can be Lorentz-boosted. Using these wave functions, I was able to show that the quark model and Feynman's parton picture were two different manifestations of one covariant entity. These oscillator wave functions later became the mathematical base for squeezed states of light.

  Let us go back to 1970. Why was I so excited? Five years earlier, Freeman Dyson gave an invited talk at the same APS meeting. He made an important remark which led to the so-called "Dashen-Frautchi Fiasco." I published a paper about their work, and I was in political hot water for several years [the issue was that Dashen is a genius but Kim was something else]. Click here, if you are interested.

  Click on the figure for a detailed story.

• During those difficult years, I came to the conclusion that the present form of quantum field theory with Feynman diagrams cannot solve the problem of bound-state problems with localized probability distribution, as illustrated in this figure. I was a very lonely person in the physics world where quantum field theory was thought to be the ultimate unification of quantum mechanics and special relativity. Naturally, I was excited to hear Feynman saying that we should try localized harmonic oscillator wave functions for bound states instead of Feynman diagrams. In short, Feynman was telling to complete Step 1 given in the figure, and I did. Indeed, R. P. Feynman was my savior.

• I am still working on Feynman's physics. You may click on my Feynman Agenda to see where the story stands these days.

  Click here if you are interested in my Feynman page.

copyright@2021 by Y. S. Kim, unless otherwise specified.

How did I talk to Einstein?

1. Click here for his home page.
2. His photo-biography.
3. His Princeton page.
4. His Einstein page.
5. His Style page.

I received my PhD degree from Princeton in 1961, seven years after high school graduation in 1954. This means that I did much of the ground work for the degree during my high school years.