Surface phenomena in thin-film tribology

Dynamics of bodies and systems or tribology of contacts are ultimately described in terms of prevailing balance of forces. This has been the human understanding of Nature and all the devised mechanisms and machines ever since proper description of what is understood to constitute a force in the 17th Century by Newton (1687). The most important force of Nature is force of gravity. Although empirical in nature, it fitted the measured observations made previously by Kepler (1609). It is no wonder that, apart from some exceptions the successive pioneers tried to fit similar force laws to other interaction phenomena, such as Coulomb‟s electrostatic force between charged particles, which follows the same inverse distance squared law as that of universal gravitation. The elegance in the universality of gravitational constant, however, could not be retained for constants of proportionality between the force and distance for these other force laws...