Sometimes the simplest questions are the most ve. One of the biggest questions in science right now is simply: Why is there something rather than nothing? While it might sound like a debate topic for stoners, it's a serious and profound question about the nature of the universe. And now, in Japan could be the first step toward answering it.
The Big Bang created all the matter that currently makes up our universe. All the particles, like protons, neutrons, and electrons, were created in the first few moment of the universe. But the Big Bang also created antimatter, which is the opposite of regular matter, kind of like a mirror image of regular particles. When particles and antiparticles collide, they annihilate each other and release a tremendous amount of energy. Much of the early universe consisted of matter and antimatter explosions, and most of the matter and all of the antimatter was destroyed.
The problem for physicists is how to explain why there's still some matter left over. Because antiparticles are exactly equal and opposite of normal particles, they should have been created in exactly equal numbers during the Big Bang. The antimatter should have annihilated all the regular matter, leaving nothing left over. But it didn't.
Researchers at the T2K neutrino detector in Japan have announced a result that may be a first step to explaining this mystery. For the first time, they have observed significant differences between a particle and its antiparticle, meaning that antimatter may not be the perfect mirror image that scientists thought it was.
The researchers were studying antineutrinos, a type of antiparticle. There are three types of antineutrino just as there are three types of regular neutrino—electron, muon, and tau. These three types can sometimes spontaneously change into other types. The researchers were studying these transformations when they discovered that one kind of antineutrino, the muon antineutrino, transforms less frequently than the normal neutrino.
This may sound small, but it means that there are fundamental differences between neutrinos and antineutrinos, and possibly between other types of particles and their corresponding antiparticles. This discovery will spur additional experiments which may finally tell us why there's something instead of nothing.