The theory of tiny particles isn't complete. But new discoveries are helping scientists expand it.
The LHCb experiment at CERN has discovered three new 'pentaquark' particles being created in high energy particle collisions at the Large Hadron Collider.
A particle physicist explains just what this keystone theory includes. After 50 years, it's the best we've got to answer what everything in the universe is made of and how it all holds together.