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Jeudi 8 avril
Résumé :
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.
RECRUTEMENT ACCES DIRECT
Le département de physique
Fête de la Science 2018 