Fall 2022 Physics Colloquium: Active phases and phase transitions in bacterial populations

Presented by: Joshua W. Shaevitz, Professor of Physics, Lewis-Sigler Institute Princeton University

Abstract: Many bacteria naturally live in dense groups where self-propulsion of individual cells gives rise to a population whose material properties are those of an active fluid. Elongated cells experience nematic and polar interactions producing biofilms that are subject to the physics of liquid crystals. Compared to their passive counter parts, active liquid crystals can form unique, symmetry breaking phases that can exhibit directed motion. Even more exotic, living cells can sense their environment and respond by changing their motility and interactions, thus driving phase transitions from the bottom up. I will present results from studying the soil-dwelling bacterium Myxococcus xanthus, a species that has evolved to use such active-matter phases and phase transitions to hunt prey and survive long periods of starvation.

Refreshments served in PAS 218, 2:45PM - 3PM

Note: All Department of Physics Fall 2022 Colloquium are in-person only


3 p.m. Sept. 23, 2022


PAS 201