Events
Upcoming Event
WED@NICO SEMINAR: Joseph Paulsen, Syracuse University "Computing with a pile of sand: Understanding amorphous solids that "count" modulo n"
Northwestern Institute on Complex Systems (NICO)
12:00 PM
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Lower Level, Chambers Hall
Details
Speaker:
Joseph Paulsen, Associate Professor, Department of Physics, Syracuse University
Title:
Computing with a pile of sand: Understanding amorphous solids that “count” modulo n
Abstract:
In a perfect crystalline solid, the location of its ~1023 atoms can be determined from the whereabouts of just a handful of them. This highly symmetric structure underlies our modern theories of the solid state. By contrast, amorphous solids appear to be a jumbled mess — their lack of symmetry complicates predictions of their mechanical properties and can lead to unusual behaviors. Here we consider an intriguing response seen in simulations of amorphous solids under repeated shearing: the solid may repeatedly visit two distinct configurations at the end of each driving cycle; one at the end of each “even” cycle and one at the end of each “odd” cycle. We build a phenomenological model based on localized rearrangements in the material, which we show can form a faithful picture of this “multiperiodic” response. Beyond elucidating the physics of randomly-packed grains, our results provide a bonus: We obtain a set of design principles for mechanical metamaterials that can “count” the number of times they are disturbed.
Speaker Bio:
Joseph Paulsen earned a bachelor's degrees in Mathematics and Physics from St. Olaf College in Northfield, MN, and he completed his PhD in Physics at the University of Chicago with Sidney Nagel. He won a National Science Foundation CAREER Award for his work that studies connections between geometry and mechanics in thin materials. Outside of science, one of his passions is trying to squirrel away as much time as possible to ski with his 7-year-old daughter (his son and his wife are not skiers... yet).
Location:
In person: Chambers Hall, 600 Foster Street, Lower Level
Remote option: https://northwestern.zoom.us/j/94291553667
Passcode: NICO2024
About the Speaker Series:
Wednesdays@NICO is a vibrant weekly seminar series focusing broadly on the topics of complex systems, data science and network science. It brings together attendees ranging from graduate students to senior faculty who span all of the schools across Northwestern, from applied math to sociology to biology and every discipline in-between. Please visit: https://bit.ly/WedatNICO for information on future speakers.
Time
Wednesday, May 29, 2024 at 12:00 PM - 1:00 PM
Location
Lower Level, Chambers Hall Map
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)
WED@NICO SEMINAR: Serguei Saavedra, MIT "How Do Ecological Systems Become (re)Assembled?"
Northwestern Institute on Complex Systems (NICO)
12:00 PM
//
Lower Level, Chambers Hall
Details
Speaker:
Serguei Saavedra, Associate Professor, Department of Civil and Environmental Engineering, MIT
Title:
How Do Ecological Systems Become (re)Assembled?
Abstract:
One of the most iconic thought experiments in biology is what would happen if we could rewind the tape of life on Earth and play it again. Would the tape have a different story in every replay? Or is there a general order of events? The relevance of this thought experiment is not just philosophical or counterfactual, because (re)assembly processes undergone by ecological systems, from microbes to mega-fauna, are continuously replicating the experiment. By integrating theoretical and empirical work, in this talk I will provide a guideline to increase our understanding about the (re)assembly possibilities of ecological systems. Explaining and predicting the (re)assembly of ecological systems underpins our ability to develop successful interventions in bio-restoration, bio-technologies, and bio-medicine.
Speaker Bio:
Serguei Saavedra is an Associate Professor at MIT in the Department of Civil and Environmental Engineering. He is also an external faculty at Santa Fe Institute. Serguei is a theoretical ecologist focused on understanding the feasibility of observing the emergence, transformations, and regeneration of ecological systems under environmental changes. Before joining MIT in 2016, Serguei studied systems engineering in Mexico; specialized in mathematical modeling at Genoa University; completed his PhD in engineering science at Oxford University; and did his postdoctoral work at the NICO (under the mentorship of Brian Uzzi), Doñana Biological Station, and in the department of environmental systems at ETH.
Location:
In person: Chambers Hall, 600 Foster Street, Lower Level
Remote option: https://northwestern.zoom.us/j/91082510906
Passcode: NICO2024
About the Speaker Series:
Wednesdays@NICO is a vibrant weekly seminar series focusing broadly on the topics of complex systems, data science and network science. It brings together attendees ranging from graduate students to senior faculty who span all of the schools across Northwestern, from applied math to sociology to biology and every discipline in-between. Please visit: https://bit.ly/WedatNICO for information on future speakers.
Time
Wednesday, May 22, 2024 at 12:00 PM - 1:00 PM
Location
Lower Level, Chambers Hall Map
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)