Hideki Yukawa at the left end. This photo was taken when he was a student of the Third High School.

This photo was taken the roof of the building that housed the School of Science, Osaka Imperial University (Nakanoshima) (circa 1934 to 1937). In the front row: Seishi Kikuchi at the center, Tasaburo Yamaguchi at the left, and Shoten Oka at the right. In the back row from the left: Hideki Yukawa, Yuzuru Watase, Hiroo Kumagai (Aoki), Koji Fushimi, and Shoichi Sakata.

Hideki Yukawa at the age of 32, in 1939. This photo was taken immediately before Yukawa left Japan for his first overseas trip to attend the Solvay Conference on Physics. He was invited to the Solvay Conference on Physics held in October 1939, and left Kobe at the end of June on the Yasukuni Maru steamer for his first overseas journey. He arrived at Naples in early August; however, because the Conference was postponed indefinitely due to the breakout of the Second World War, on August 26 Yukawa boarded the Yasukuni Maru that had been waiting in Hamburg to return to Japan. Shin-ichiro Tomonaga, who was studying at Leipzig University at that time, also returned to Japan on the same ship. When the ship called at the port in New York, Yukawa disembarked from the ship alone and stayed in the United States. He stayed there for about one month, traveling by train to Princeton University to meet Albert Einstein and to various other places to deepen his relationships with many physicists. Yukawa boarded the Kamakura Maru at San Francisco and arrived at Yokohama on 28th. Yukawa had a post at Osaka Imperial University in early April 1939, when he received the invitation to the Solvay Conference on Physics, but he took a position in Kyoto Imperial University on May 26 as the successor of his former mentor, Professor Kajuro Tamaki, who died suddenly in the previous year.

Hideki Yukawa at the age of 35, in May 1942. This photo was taken in front of Todai-ji Temple’s Sangatsu-do Hall during the visit to Nara for a picnic. In the front row from the right: Hideki Yukawa, Minoru Kobayashi, Shoichi Sakata, Matsuhei Tamura, and Yasutaka Tanikawa. They discussed about the concept of two meson theory, as proposed by Tanikawa. Therefore, it is called “Two meson theory hiking.”

Hideki Yukawa and Shoichi Sakata

Hideki Yukawa at the age of 36, in April 1943. He received the Decoration of Cultural Merit in this year. In 1940, he was awarded the Imperial Prize of the Japan Academy at the age of 33 years.

Hideki Yukawa giving a lecture at Osaka Senior High School on June 7, 1944.. This photo was donated by Class 1, Grade 2 in the Faculty of Science English Category.

Hideki Yukawa

Hideki Yukawa at the age of 40, in 1948. Self-portrait on New Year’s Day.

In September 1948, Yukawa was invited to the Institute for Advanced Study in Princeton, so he traveled to the United States. This photo was taken in Berkeley, California. Yukawa wanted to visit the Lawrence Radiation Laboratory at the University of California, Berkeley as soon as he arrived in the U.S. In Berkeley, Yukawa met Prof. Fermi and other physicists of the University of Chicago who were staying in Berkeley for the summer lectures. From the left: Enrico Fermi, Emilio Segrè, Hideki Yukawa, and James Chadwick.

In Berkeley, September 1948. In the back row from the left: Earnest Lawrence, Robert Serber, and Mr. and Mrs. Yukawa.

With Abraham Pais in Princeton

The Yukawa family visited Albert Einstein in Princeton. Photo taken by Mrs. Yukawa. (around 1949)

With Max von Laue in Princeton

In Princeton

Hideki Yukawa at the age of 42, in 1949. This is a photo of Yukawa and Isidor Rabi taken by a staff member at Columbia University’s Public Information Center after receiving the news about Yukawa receiving the Nobel Prize.

At Columbia University

Hideki Yukawa and Isidor Rabi in Yukawa’s lab at Columbia University. Isidor Rabi was the first professor of Columbia University to receive the Nobel Prize in physics, and Yukawa was the second Nobel Prize winner. The blackboard behind them was relocated to Osaka University Graduate School of Science Building H in 2014.

This photo was taken in Princeton after receiving the news of Yukawa receiving the Nobel Prize. From the right: Shin-ichiro Tomonaga, Hideki Yukawa, and J. Robert Oppenheimer.

Nobel Prize diploma

Front side of the Nobel Prize medal bearing the portrait of Alfred Nobel.

Back side of the Nobel Prize medal bearing the image of Scientia (= science) removing the veil from the head of Natura (= nature).

This photo was taken in Kyoto University in 1950. In the front row from the right: Shoichi Sakata, Shin-ichiro Tomonaga, and Hideki Yukawa. In the back row: Yoichiro Nambu (at the right end) and Ryoyu Uchiyama (second from the left end).

At Osaka University, 1950. Hideki Yukawa is the second person from the right end in the front row.

With Yoshio Nishina in Hakone, August 1950. (Photo taken by Mainichi Newspapers)

Hideki Yukawa at the age of 45, in December 1952. Yukawa and Robert Marshak at the 3rd Rochester Conference.

In Lindau, Germany, July 1953. This photo was taken at the lectures of Nobel Prize winners. From the left: Paul Dirac (British), Folke Bernadotte (Swedish), Cecil Powell (British), Max von Laue (German), Georg von Hevesy (Swedish), Otto Hahn (German), and Hideki Yukawa.

In Lindau, Germany. Leonhard Euler (Swedish) is the second person from the left end, and Adolf Butenandt (German) is the third person.

Hideki Yukawa and Paul Dirac in Lindau, Germany. Dirac was a quiet person and a type of a researcher who preferred to work alone. So, it is said that the photo of Dirac with another person is a rarity.

In Lindau

Hideki Yukawa and his wife, Sumi

Hideki Yukawa loved Kyoto and its culture. The photo of Yukawa with Mr. and Mrs. Gregor Wentzel was taken at Ginkaku-ji Temple.