School of Physics Colloquium

Active materials such as bacteria, molecular motors and eukaryotic cells continuously
transform chemical energy taken from their surroundings to mechanical work. Dense active
matter shows mesoscale turbulence, the emergence of chaotic flow structures characterised
by high vorticity and self-propelled topological defects. I shall describe the physics of active
defects, discussing active microfluidics, the formation of defect lattices and examples of
topological defects in biological systems.