Chiral symmetry restoration
Chiral symmetry is:
- a symmetry of light flavors due to the small quark masses: mu, md
- explicitly broken due to the finite u,d quark masses
- also spontaneously broken in nature leading to
- Goldstone bosons (p+/-/0)
- hadronic spectra
- splitting of pseudo-scalar/scalar and vector/axial-vector particles
- same quantum #’s … different parity
- Restored at high temperature and density.