title: Geometric approach to the dynamic glass transition.
abstract: We numerically study the potential energy landscape of a fragile glassy system and find that the dynamic crossover corresponding to the glass transition is actually the effect of an underlying geometric transition caused by the vanishing of the instability index of saddle points of the potential energy. Furthermore, we show that the potential energy barriers connecting local glassy minima increase with decreasing energy of the minima, and we relate this behavior to the fragility of the system. Finally, we analyze the real space structure of activated processes by studying the distribution of particle displacements for local minima connected by simple saddles.
authors.affiliation: Dipartimento di Fisica, Unità INFM and Sezione INFN Università di Roma La Sapienza, 00185 Roma, Italy.
authors.forename: Tomás S
authors.initials: TS
authors.lastname: Grigera
authors.forename: Andrea
authors.initials: A
authors.lastname: Cavagna
authors.forename: Irene
authors.initials: I
authors.lastname: Giardina
authors.forename: Giorgio
authors.initials: G
authors.lastname: Parisi