# Ruoyu Wu: Graphon mean field systems: large population and long-time asymptotics

**Time: **
Mon 2022-05-16 15.15 - 16.15

**Location: **
Zoom

**Video link: **
Zoom meeting ID: 621 4469 8204

**Lecturer: **
Ruoyu Wu (Iowa State University)

### Abstract

We consider heterogeneously interacting diffusive particle systems and their large population limit. The interaction is of mean field type with random weights characterized by an underlying graphon. The limit is given by a graphon particle system consisting of independent but heterogeneous nonlinear diffusions whose probability distributions are fully coupled. A law of large numbers result is established as the system size increases and the underlying graphons converge. Under suitable convexity assumptions, we show the exponential ergodicity for the system, establish the uniform in time law of large numbers and concentration bounds, and analyze the uniform in time Euler approximation. The precise rate of convergence of the Euler approximation is provided. Based on joint works with Erhan Bayraktar and Suman Chakraborty.