Dynamical aspects of fluid phases: an overview

Abstract

Much recent interest in comtemporay condensed matter physics has focussed on the physical properties of strongly correlated systems, There have been two classes of such systems which have received particular attention. The first class is that of amny-body quantum systems of fermions or bosongs, which are relevant in the context of many recent important experimental discoveries, e.g., hich-temperature superconductively, the quantum has effect, ets. The second class is that of physically relevant classical systems. e.g., dense fluids, polymers, gels, liquid crystals, etc. For the latter, there are fundamental and challenging questions regarding experimentally observed universal properties, both static and dynamic. Typically, many of these systems exhibit stretched-expontential structural relaxations; domain growth with characteristic growth exponents in far-from-equilibrium phase ordering situations; intermediate behavior between fluids and solids; and so on. The static properties of these systems have been extensively studies and are now relatively well understood. As far as dynamical properties are concerned, there is a set of challenging problems which requires the application of ideas from diverse research areas like nonlinear dynamics, disordered systems and nonequillibrium statistical mechnics. The study of dynamical properties of these systems has given rise to a new and very active field of research, often referred to as "Relaxation iin Complex Systems". This new field of research has acquired a truly interdisciplinary nature as it brings together physicists, physical chemists and metallurgists.