19 décembre 2018 11h salle des thèses de Labège Zhen Li, actuellement en visite au département GIMD, fera un séminaire à la salle des thèses (Labège) mercredi 19/12 à 11h. Mathematical and Physical
19 décembre 2018 11h
salle des thèses de Labège
Zhen Li, actuellement en visite au département GIMD, fera un séminaire à la salle des thèses (Labège) mercredi 19/12 à 11h.
Mathematical and Physical Foundation of Coarse-Graining and Applications to Multiscale Problems
Abstract: Multiscale features in many interesting physical systems originate from hierarchical structures across a wide range of temporal and spatial scales beyond the reach of any single simulation method. Mesoscopic methods can seamlessly bridge the gap from microscopic scales to macroscopic scales, and thus become key scientific approach playing unique roles in research of multiscale problems. In this talk, I will first introduce mathematical and physical foundations of coarse-graining and derive new governing equations of mesoscopic models. I will subsequently present the details of a coarse-graining procedure based on the rigorous theoretical approach of the Mori-Zwanzig (MZ) formalism, by running molecular dynamics simulations and constructing the MZ-informed mesoscopic model directly from atomistic trajectories, as well as computing the memory terms in coarse-grained dynamics. Also, I will talk about different coarse-graining strategies with generalized Langevin equations and non-Markovian dissipative particle dynamics models to incorporate the memory effects in practical coarse-grained simulations. Moreover, I will show several examples of mesoscopic models applied to smart materials, biology processes, and diverse multiscale problems, including coupling of heterogeneous solvers, active-learning algorithm applied to multiscale simulations, and supervised parallel-in-time algorithm for long-time stochastic simulations.
Short Biography: Dr. Zhen Li is Associate Professor of Applied Mathematics (Research) at Brown University. His research focuses on multiscale modeling for bridging scales in multiscale/multiphysics problems, in particular on mathematical and physical foundations of coarse-graining, and development of mesoscopic methods and multiscale frameworks with applications to complex fluids, computational biology and soft matter physics.
(Wednesday) 11 h 00 min - 12 h 00 min
Salle des thèses ENSIACET