BEGIN:VCALENDAR VERSION:2.0 PRODID:-//132.216.98.100//NONSGML kigkonsult.se iCalcreator 2.20.4// BEGIN:VEVENT UID:20260622T005826EDT-4234VMPioc@132.216.98.100 DTSTAMP:20260622T045826Z DESCRIPTION:Title: Topological data analysis of collective dynamics\n\nAbst ract:\n\nFrom nanoparticle assembly to synchronized neurons to locust swar ms\, collective behaviors abound anywhere in nature that objects or agents interact. Investigators modeling collective behavior face a variety of ch allenges involving data from simulation and/or experiment. These challenge s include exploring large\, complex data sets to understand and characteri ze the system\, inferring the model parameters that most accurately reflec t a given data set\, and assessing the goodness-of-fit between experimenta l data sets and proposed models. Topological data analysis provides a lens through which these challenges may be addressed. This talk consists of th ree parts. In the first part\, I apply topological data analysis to the se minal aggregation model of Vicsek et al. (1995) in order to identify dynam ical events that traditional methods do not. In the second part\, I use to pological data analysis to choose between unbiased correlated random walk models that potentially describe motion tracking experiments on pea aphids . Finally\, moving towards a theory of reduced topological descriptions of complex behavior\, I present open questions on the topology of random dat a\, complementing research in random geometric graph theory. Throughout th e talk\, the key approach is to characterize a system's dynamics via the t ime-evolution of topological invariants called Betti numbers\, accounting for persistence of topological features across multiple scales. No prior k nowledge of topology is necessary.\n DTSTART:20190218T210000Z DTEND:20190218T220000Z LOCATION:Room 1104\, Burnside Hall\, CA\, QC\, Montreal\, H3A 0B9\, 805 rue Sherbrooke Ouest SUMMARY:Chad Topaz (Williams College) URL:/mathstat/channels/event/chad-topaz-williams-colle ge-294649 END:VEVENT END:VCALENDAR