Thermodynamic geometry of Nambu–Jona Lasinio model

The formalism of Riemannian geometry is applied to study the phase transitions in Nambu–Jona Lasinio (NJL) model. Thermodynamic geometry reliably describes the phase diagram, both in the chiral limit and for finite quark masses. The different thermodynamic geometrical behavior of NJL model and of (2+1) Quantum Chromodynamics at high temperature and small baryon density gives some hints on the connection between chiral symmetry restoration/breaking and deconfinement/confinement regimes.