Nobel Prize for Physics goes to Takaaki Kajita and Arthur B McDonald, for neutrino work that helped understand ‘nature’s most elusive particles’

Neutrinos are very common fundamental particles in the universe — but we still don’t know all that much about them

Journalists wait for the beginning of a press conference of the Nobel Committee to announce the winner of the 2015 Nobel Prize in Physics on October 6, 2015 at the Swedish Academy of Sciences in Stockholm, Sweden (JONATHAN NACKSTRAND/AFP/Getty Images)

Two physicists have won the Nobel Prize for Physics for their work to discover that neutrinos have a mass — one of the few things that we know about the elusive particles.

Japanese Takaaki Kajita and Canadian Arthur B. McDonald were given the award today “for the discovery of neutrino oscillations, which shows that neutrinos have mass”.

The award was given to the scientists “for their key contributions to the experiments which demonstrated that neutrinos change identities”, the committee said. “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.”

Scientists know very little about neutrinos and the fact that they hardly ever interact makes them very difficult to study. For half a century scientists thought that they had no mass — but the discovery at the turn of the millennium that they actually have mass led to the work that was recognised by 2015’s prize.