News & Events
Department Events

Events

  • Oct
    19

    2026 Stephen H. Davis Lecture: Dr. Sidney Nagel on "Memory Formation in Particle Packings"

    McCormick-Engineering Sciences and Applied Mathematics (ESAM)

    4:00 PM ITW (Room 1.350), Ford Motor Company Engineering Design Center

    EVENT DETAILS

    Title: Memory Formation in Particle Packings

    Speaker: Dr. Sidney Nagel, University of Chicago

    Abstract: A disordered solid created by packing spheres in a box has a myriad of stable configurations that defy straightforward enumeration and characterization. Since structure often determines function, each distinct arrangement potentially corresponds to different material behavior. The question naturally arises: How many mechanically stable ways are there to pack N identical spheres in a box? This has the spirit of a “Fermi estimation problem,” but one for which we do not have an answer: we do not know how to account for rearranging the particles to produce packings with different connectivity. We therefore resort to measurement.

    Stable packings of N identical soft spheres in d dimensions lie at the minima of a vast (Nd)-dimensional potential energy landscape. Starting from random positions, the particles can relax to mechanical equilibrium; all initial conditions that end at the same minimum belong to the same catchment basin. We find a very wide distribution of basin volumes. These results suggest how to understand the imprinting of memories in solids.

    Bio: Sidney Nagel was educated at Columbia University (B.A. in 1969) and at Princeton University (Ph.D. in 1975). He did a postdoc at Brown and then moved to the University of Chicago in 1976 where he has remained and is now the Stein-Freiler Distinguished Service Professor in the Department of Physics and the James Franck and Enrico Fermi Institutes. Nagel is a condensed-matter experimentalist focusing on problems where the physics of disorder and far-from-equilibrium behavior play crucial roles. Of particular delight is when table-top experiments have analogs in disparate fields at wildly different scales. In particular, he has studied the glass transition, the phenomenology of granular material, and the physics of jamming; he has also focused on pattern and singularity formation in fluid interfaces, and the formation of stains left behind by evaporating liquid drops. A current interest is the investigation of memory formation in out-of-equilibrium matter. He has worked to make his science accessible to a broad public by emphasizing the inherent beauty of the phenomena he studies in the laboratory.

    Zoom: https://northwestern.zoom.us/j/98030602428

    -----

    To subscribe to the Applied Mathematics Colloquia List send a message to LISTSERV@LISTSERV.IT.NORTHWESTERN.EDU with the command:

    SUBSCRIBE esam-seminar FirstName LastName

    more less

    TIME Monday, October 19, 2026 at 4:00 PM - 5:00 PM

    LOCATION ITW (Room 1.350), Ford Motor Company Engineering Design Center    map it

    ADD TO CALENDAR

    CONTACT Natalie Masini    natalie.masini@northwestern.edu EMAIL

    CALENDAR McCormick-Engineering Sciences and Applied Mathematics (ESAM)

  • Oct
    6

    ESAM Seminar: Ehud Yariv on "Mobility of Particles in Viscous Membranes"

    McCormick-Engineering Sciences and Applied Mathematics (ESAM)

    11:00 AM M416, Technological Institute

    EVENT DETAILS

    TIME Tuesday, October 6, 2026 at 11:00 AM - 12:00 PM

    LOCATION M416, Technological Institute    map it

    ADD TO CALENDAR

    CONTACT Natalie Masini    natalie.masini@northwestern.edu EMAIL

    CALENDAR McCormick-Engineering Sciences and Applied Mathematics (ESAM)

  • Oct
    13

    ESAM Seminar: Adrianna Gillman on "Fast Direct Solvers for Boundary Integral Equations"

    McCormick-Engineering Sciences and Applied Mathematics (ESAM)

    11:00 AM M416, Technological Institute

    EVENT DETAILS

    TIME Tuesday, October 13, 2026 at 11:00 AM - 12:00 PM

    LOCATION M416, Technological Institute    map it

    ADD TO CALENDAR

    CONTACT Natalie Masini    natalie.masini@northwestern.edu EMAIL

    CALENDAR McCormick-Engineering Sciences and Applied Mathematics (ESAM)

  • Oct
    27

    ESAM Seminar: Alan Lindsay on "Advances in Asymptotic and Computational Methods for Biological Transport"

    McCormick-Engineering Sciences and Applied Mathematics (ESAM)

    11:00 AM M416, Technological Institute

    EVENT DETAILS

    TIME Tuesday, October 27, 2026 at 11:00 AM - 12:00 PM

    LOCATION M416, Technological Institute    map it

    ADD TO CALENDAR

    CONTACT Natalie Masini    natalie.masini@northwestern.edu EMAIL

    CALENDAR McCormick-Engineering Sciences and Applied Mathematics (ESAM)

  • Dec
    12

    Northwestern Engineering PhD Hooding and Master's Recognition Ceremony

    McCormick School of Engineering and Applied Science

    4:00 PM Pick-Staiger Concert Hall

    EVENT DETAILSmore info

    TIME Saturday, December 12, 2026 at 4:00 PM - 6:00 PM

    LOCATION Pick-Staiger Concert Hall    map it

    ADD TO CALENDAR

    CONTACT Andi Joppie    andi.joppie@northwestern.edu EMAIL

    CALENDAR McCormick School of Engineering and Applied Science