Physicists Don't Know the Mass of a Neutrino, But Now They Know it's No Larger Than 1 Electron Volt

The Standard Model of Particle Physics is one of science’s most impressive feats. It’s a rigorous, precise effort to understand and describe three of the four fundamental forces of the Universe: the electromagnetic force, the strong nuclear force, and the weak nuclear force. Gravity is absent because so far, fitting it into the Standard Model …