The pion: an enigma within the Standard Model

Understand

Almost 50 years after the discovery of gluons & quarks, we are only just beginning to understand how QCD builds the basic bricks for nuclei: neutrons, protons, and the pions that bind them.

• QCD is characterised by two emergent phenomena: confinement & dynamical chiral symmetry breaking (DCSB).
• They are expressed with great force in the character of the pion.
• In turn, pion properties suggest that confinement & DCSB are closely connected.