Yukawa received a Nobel Prize in 1949 for predicting the pi meson but while in Japan he published his theory which explained the interaction between protons and neutrons in 1935. What work did he do during the war years?
I assume his work was not needed by the United States to complete the A-Bomb but did Japan keep it secret since he worked in Japan ?
If it was published I am wondering what the U.S. reaction was considering the U.S. had banned any mention of atomic physics in any form be stripped from any publications in the United States and this also included the press as well as scientists in the U.S.