ESPCI web site
Active Matter : evading the decay to equilibrium
Biological systems avoid equilibrium by taking chemical energy from their
surroundings and using it to do work. Cells organise intra-cellular components into
the structures that allow them to grow, reproduce and move. Tissues, collections of
cells, differentiate locally as they develop to perform the complex functions of
different organs.
Active systems, also exist out of thermodynamic equilibrium. Dense active matter
shows complex collective behaviour and mesoscale turbulence, the emergence of
chaotic flow structures characterised by high vorticity and self-propelled topological
defects. I shall describe the physics of dense active matter and discuss possible
links to motility and morphogenesis in biological contexts.