Takaaki Kajita of Japan and Arthur McDonald of Canada won the Nobel
Prize in physics on Tuesday for discovering that tiny particles called
neutrinos change identities as they whiz through the universe, proving
that they have mass.
By uncovering the "chameleon-like" nature of neutrinos, the laureates had solved a long-standing puzzle in particle physics that could alter our grasp of the cosmos, the Royal Swedish Academy of Sciences said.