Topic 2. Coarse-graining techniques and truly multiscale simulations

To treat large systems and run simulations for longer times, we typically need to resort to simpler, coarse-grained models, especially if the driving forces behind the (collective) phenomena of interest naturally manifest themselves at larger length and time scales. To arrive at an efficient description of the system, a hierarchy of simulation tools must be employed, collectively referred to as multiscale modeling.

Our Symposium will discuss challenges and state-of-the-art research efforts in the field, and will highlight both new methodological and theoretical developments and multiscale simulations using systematic coarse-graining for equilibrium and extended (nonequilibrium) systems. Particular attention is given to:

• Linking simulations of detailed models with simulations of coarse-grained ones (with emphasis on the efficient flow of information between models)
• Emergence of irreversibility, microscopic calculation of coarse-grained coefficients, characterization of rare events, dynamical coarse-graining even in systems without time-scale separation, generalizations of fluctuation-dissipation relationships, multiple-time step schemes for multi-resolved models
• Variational approaches to coarse-graining of equilibrium and nonequilibrium descriptions
• Coarse-grained models and multi-scale simulation methods for transport phenomena and structure evolution in nonequilibrium systems at transient or steady-state regimes, preferably guided by principles of nonequilibrium thermodynamics or derived in a systematic way using nonequilibrium statistical mechanics.

Our purpose is to bring leading experts together to discuss methods that are neither problem-specific nor fragmented (thus applicable in a broader context), and to describe future challenges. We hope our Symposium to provide a special opportunity to connect domain experts from scientific and engineering disciplines with specialists in mathematical and computational analysis, and to integrate efforts that are diverse or remain isolated in different disciplines.

Teachers (Summer school)

• Pep Español   Universidad Nacional de Educacion Distancia, Spain
• Patrick Ilg   University of Reading, United Kingdom

Topic organizers

• Vlasis Mavrantzas   University of Patras, Greece
• Patrick Ilg   University of Reading, United Kingdom

2025