Du transport dans les canaux à l’évolution des populations : comment les hétérogénéités façonnent la dynamique

Arthur Alexandre (EPFL)

In this seminar, I will discuss two problems where effective descriptions capture the essential mechanisms at play: one from hydrodynamics and one from population genetics.

In hydrodynamics, Taylor dispersion describes the enhanced spreading of particles in a fluid due to the combined effects of diffusion and flow. We show how this phenomenon can be understood in complex, tortuous channels using an effective model that captures the main transport properties, providing insight into flows in porous media.

In population genetics, the gut microbiota presents extensive genetic diversity shaped by its flow-dominated environment. Using a minimal model that incorporates flow, diffusion, and microbial growth, we show how spatial structure and advection influence the fixation of beneficial mutants, highlighting the interplay between flow, growth, and spatial heterogeneity in shaping microbial evolution.

Contact : M. Manghi