BEGIN:VCALENDAR VERSION:2.0 PRODID:-//132.216.98.100//NONSGML kigkonsult.se iCalcreator 2.20.4// BEGIN:VEVENT UID:20250918T140941EDT-5267c3fsjL@132.216.98.100 DTSTAMP:20250918T180941Z DESCRIPTION:Title: The Fourier transform on Convergent Graph Sequences\n \n A bstract:\n A graph signal is a function on the vertices of a graph. Example s of graph signals are: viral load of patients connected through a contact network\, or fMRI signals on brain regions linked by functional or physic al connections. The graph Fourier transform is a projection of the signal onto the eigenbasis of the adjacency matrix the graph. The matrix is refer red to as the shift operator and represents the time evolution of a signal over a graph.\n\nSequences of graphs that have similar structure\, in ter ms of homomorphism densities\, converge to a {\sl graphon}. A graphon is a symmetric\, measurable function on $[0\,1]^2$ which can be interpreted as a random graph model. Graphs in a graph sequence converging to a graphon have structure typical of samples from this model. I will present a common framework\, derived from the graphon\, to define the Fourier transform of such sampled graphs. We recently showed that this approach has the desire d convergence properties. I will also discuss the special case of graphs s ampled from a {\sl Cayley graphon}. Such graphs are stochastic versions of Cayley graphs. The representations of the underlying group allow us to de fine a basis for the graphon Fourier transform.\n \n This is joint work with Mahya Ghandehari and Nauzer Kalyaniwalla.\n\n \n DTSTART:20221206T180000Z DTEND:20221206T190000Z LOCATION:Room 1214\, Burnside Hall\, CA\, QC\, Montreal\, H3A 0B9\, 805 rue Sherbrooke Ouest SUMMARY:Jeannette Janssen (Dalhousie University) URL:/mathstat/channels/event/jeannette-janssen-dalhous ie-university-344079 END:VEVENT END:VCALENDAR