Asked in PhysicsQuantum Mechanics
Why are leptons divided into families?
September 13, 2012 10:12PM
Leptons are divided into three families with 4 particles (2 particles, plus their two anti-particles) in each family. In the electron family we have the electron, positron, electron neutrino and electron anti-neutrino. Each family has a higher mass than the one before it so the tauon is heavier than the muon which is heavier than the electron. The physical reason for there being three families is completely unknown and will probably win you a Nobel prize if you can figure it out!