Tribology, which studies surfaces in contact and relative motion, includes friction, wear, and lubrication, straddling across different fields: mechanical engineering, materials science, chemistry, nanoscience, and physics [1].
Despite the fundamental, practical and technological importance of tribology, several key physical aspects of mechanical dissipative phenomena are not yet fully understood, mostly due to the complexity of highly out-of-equilibrium non-linear processes often occurring across ill-characterized sliding interfaces. Progress at the fundamental physics level is going on both through nanofriction experiments and through theory from computer simulations to non-equilibrium statistical mechanics.
References:
1. N. Manini, G. Mistura, G. Paolicelli, E. Tosatti and A. Vanossi, Current trends in the physics of nanoscale friction, Adv. Phys. X 2, 569-590 (2017).