Levich Institute Seminar Announcement, 12/04/2007
Tuesday, 12/04/2007
2:00 PM
Steinman Hall, Room #312
(Chemical Engineering Conference Room)

Professor Hernan Makse
City College of CUNY
Levich Institute

"Statistical Mechanics of Jammed Matter"


ABSTRACT


We employ statistical mechanics of jammed matter to demonstrate the phase diagram of all available jammed configurations of frictional and frictionless granular packings. This provides a statistical definition of RLP and RCP, predicts their density values in close agreement with simulations, and establishes the concomitant equations of state relating observables such as the coordination number, z, entropy, S, and volume fraction, phi. We show that the RCP state is not a unique point in the phase space but extends along a line of zero compactivity, a temperature-like variable, predicted to be at a constant Phi_RCP = 0.634, but with different z. The lowest density of RLP appears as a line of infinite compactivity parameterized by z, ending at the minimum possible density theoretically predicted to be Phi_RLP = 0.543. The nature of the disorder of the packings is statistically characterized by the entropy which is shown to be larger in the random loose case than in the random close case.

BRIEF ACADEMIC/EMPLOYMENT BACKGROUND:

  • Ph.D. in Physics, Boston University, "Statistical Patterns in Nature: Growing order out of randomness", (Prof. H. Eugene Stanley, advisor), September 1993 - January 1997.
  • ``Licenciatura'' in Physics, Universidad de Buenos Aires, Argentina, 1991.
  • Currently, Associate Professor of Physics, Levich Institute and Department of Physics, City College of New York.

CURRENT RESEARCH INTERESTS:

We try to focus on the study of jammed matter, spanning from colloidal suspensions, dense emulsions to granular materials and glasses in search of unifying theoretical frameworks. We explore this variety of out of equilibrium systems in terms of their behavior as they experience structural arrest or jamming. The group focuses on the theoretical and computational approaches in parallel with the experiments, creating a productive research environment. We are also interested in the theoretical understanding of complexity. We are working towards the development of new arquitectural laws for complex networks, from biological systems, to the Internet, to social networks.