It’s even possible that neutrinos can act as their own antiparticles—that is, that neutrinos could turn into antineutrinos and vice versa. This scenario, which the discovery of right-handed neutrinos would support, would make neutrinos fundamentally different from more familiar particles like quarks and electrons. If antineutrinos can turn into neutrinos, that could help explain where the antimatter went during the universe’s earliest moments.
One way to test this idea is to look for an unusual type of radioactive decay — theorized but thus far never observed—known as “neutrinoless double-beta decay.” In regular double-beta decay, two neutrons in a nucleus simultaneously decay into protons, releasing two electrons and two antineutrinos
→ Continue reading at Ars Technica