TOKYO -- One of the great unsolved mysteries of physics is that current science can account for just 5% or so of the mass of the universe. The rest consists of so-called dark matter and dark energy, which scientists cannot yet explain. The proof that neutrinos have mass -- what the winners of the 2015 Nobel Prize in physics achieved -- could contribute toward solving that mystery.
Another major challenge in physics is that both particles and corresponding antiparticles should have been created in the Big Bang, but almost all of the antiparticles have disappeared. Though theories have emerged that explain most of this asymmetry, some gaps remain. The odd behavior of neutrinos offers a clue to filling them in.