# Bartek Waclaw

Bartek Waclaw abstract

**Bartek Waclaw**, School of Physics, UoE

Mathematical problems in the physics of growing bacterial populations

Bacterial populations- example of which are macroscopic colonies of microorganisms grown on Petri dishes by biologists - are important and interesting area of research for biologists, physicists, and engineers. However, the complexity of interactions: physical (such as excluded volume), chemical (nutrient consumption or secretion of metabolites), or biological (conjugation - a form of microbial sex) makes it very difficult to model such populations mathematically, and hence most research in this area is based on computer simulations and (very) approximate calculations. In this talk I will discuss my experimental/numerical/mathematical investigation of certain aspects of bacterial growth, which I hope will be interesting for both the biologically- and mathematically-oriented part of the audience. In particular, I will talk about the speed of expansion of a bacterial colony confined between an agarose and a glass surface (typical situation in microscopy imaging), the process of acquiring resistance to drugs, and genetic heterogeneity (the number of bacterial "mutants") in expanding, spatially heterogeneous populations. I will also present a few open problems related to these themes.