Stockholm: The Nobel Prize in Physics 2015 has been awarded to Japan’s Takaaki Kajita and Canadian Arthur B. McDonald for their key contributions to the experiments in neutrinos change identities. This metamorphosis requires that neutrinos have mass. The discovery has changed our understanding of the innermost workings of matter and can prove crucial to our view of the universe.
Takaaki Kajita presented the discovery that neutrinos from the atmosphere switch between two identities on their way to the Super-Kamiokande detector in Japan.Meanwhile, the research group in Canada led by Arthur B McDonald could demonstrate that the neutrinos from the Sun were not disappearing on their way to Earth. Instead they were captured with a different identity when arriving to the Sudbury Neutrino Observatory.
The two experiments discovered that the neutrinos had changed identities.The discovery led to the far-reaching conclusion that neutrinos, which for a long time were considered mass less, must have some mass, however small.