Van der Waals-Zeeman Colloquium

Tuesday, 20 April 2010, 16:00

The Glass Transition

Prof. Giulio Biroli
Institut de Physique Théorique, CEA Saclay

When a liquid is super-cooled below the crystallisation transition, its relaxation time increases dramatically. A mere temperature decrease of one third of the crystallisation temperature makes the viscosity shoot up of fourteen, or more, orders of magnitude. The relaxation time increases so much, that eventually the liquid does not relax anymore on experimental time-scales and becomes an amorphous rigid material, called glass. This phenomenon--the glass transition--is common to many other systems: it emerges in soft matter and granular media at high enough density and it plays a very important role even in other branches of science, such as computer science and combinatorial optimization. The glass transition remains a conundrum yet to be fully explained and which does not seem to fit in well with the standard theory of phase transitions. Recently, there has been a lot of progress: growing dynamical correlations have been identified; it has been shown that amorphous order is developing approaching the glass transition; theories, in particular the one based on mean field glassy systems, have been evolved to a point where a final answer seems within reach. In this talk, after an introduction to the glass transition and its multiple facets, I will present these new results.