SÉMINAIRE D'ANALYSE NUMÉRIQUE
Année universitaire 2015-2016




Nicolas VAUCHELET (Laboratoire Jacques-Louis Lions, Université Pierre et Marie Curie)
 Aggregation of bacteria by chemotaxis: mathematical and numerical analysis.


Chemotaxis is the phenomenon by which cells direct their motion according to a chemical present in their environment. In the case of positive chemotaxis, strong aggregation may occur that create patch. From a mathematical point of view, it leads to the study of the so-called aggregation equation which describes the interaction through a potential. Such model can be derived thanks to a hyperbolic limit of kinetic equations modelling the run-and-tumble process of bacteria. In this case the interacting potential is pointy, then solutions of aggregation equation may blow-up in finite time. In this work, we propose to study the existence of weak measure solutions for such aggregation equation, which allows to define solutions beyond the blow-up time. Our approach is based on the definition of weak measure solutions for transport equation with discontinuous coefficients. Then we investigate its numerical simulations and propose a numerical analysis.