The emergence of hadronic matter from interacting quarks and gluons

A characteristic of emergent phenomena is how novel and complex properties can emerge from apparently simple laws. Quantum ChromoDynamics (QCD) describes the interaction of quarks and gluons. The classical Lagrangian is remarkably simple. It has an SU(3) local gauge symmetry and the A_v^mu are the associated gauge fields (gluons). The quarks are fermions with fractional electrical charge. The only…