The geometric tensor for classical states

We use the Liouville eigenfunctions to define a classical version of the geometric tensor and study its relationship with the classical adiabatic gauge potential (AGP). We focus on integrable systems and show that the imaginary part of the geometric tensor is related to the Hannay curvature. The singularities of the geometric tensor and the AGP allows us to link the transition from Arnold-Liouville integrability to chaos with some of the mathematical formalism of quantum phase transitions.