A team of physicists, including some from MIT, has found surprising differences between the flavor-switching behavior of neutrinos and antineutrinos. If confirmed, the finding could help explain why matter, and not antimatter, dominates our universe. Neutrinos, elementary particles generated by nuclear reactions in the sun, "suffer from an identity crisis as they cross the universe, morphing between three different flavors.” Their antimatter counterparts do the same thing.
“People are very excited about it because it suggests that there are differences between neutrinos and antineutrinos,” says Georgia Karagiorgi, an MIT graduate student and one of the leaders of the analysis of experimental data produced by the Booster Neutrino Experiment (MiniBooNE) at the Fermi National Accelerator Laboratory.
The new results appear to be one of the first observed violations of CP symmetry: the theory that matter and antimatter should behave in the same way. CP symmetry violation has been seen before in quarks, but never in neutrinos or electrons. CP symmetry means in the words of Roger Penrose (The Road to Reality), "CP sends a particle's zig into its antiparticle's zag, and vice versa."