1) Hideki yukawa 2) Nuclear physicist 
[n] - Japanese mathematical physicist who proposed that nuclear forces are mediated by massive particles called mesons which are analogous to the photon in mediating electromagnetic forces (1907-1981)
Hideki Yukawa noun Japanese mathematical physicist who proposed that nuclear forces are mediated by massive particles called mesons which are analogous to the photon in mediating electromagnetic forces (1907-1981)
1907–81, Japanese physicist: Nobel prize 1949.