STOCKHOLM, Sweden - Two Japanese citizens and a Japanese-born American won the 2008 Nobel Prize in physics for discoveries in the world of subatomic physics, the Royal Swedish Academy of Sciences announced today.

American Yoichiro Nambu, 87, of the University of Chicago, won half of the prize for the discovery of a mechanism called spontaneous broken symmetry in subatomic physics. Makoto Kobayashi and Toshihide Maskawa of Japan shared the other half of the prize for discovering the origin of the broken symmetry that predicts the existence of at least three families of quarks in nature.