The lectures show how a theoretical approach to soft matter physics in general and, more specifically, active matter theory enable a quantitative description of biological systems, from cell to tissue. The lecture given in November and December 2021 was done in parallel with Thomas Lecuit's lecture on the same subject : the motility of isolated cells. The problem was presented from both the biologist's and the physicist's viewpoints, which are highly complementary. This gave those attending both lectures a more global view of cell motility.
The physical questions addressed concerned the basic principles of cell motility and the overall description of cell movement, the properties of the actin-myosin cytoskeleton and the mechanisms by which it enables a cell to "crawl" over a surface (or over the fibers of an extracellular medium), on the shape of moving cells, and on the movement of cells confined in a channel, whose motility mechanism, which is very different from that of crawling cells, is very similar to the motility mechanism of the three-dimensional movement of cells in a gel formed by the extracellular matrix.
There was no seminar after each lecture this year, but a colloquium we organized in June with Thomas Lecuit on the general theme of cell motility, including both individual and collective effects. Guest lecturer Eric Lauga's lecture in May and June described more hydrodynamic aspects of cell swimming in a fluid, which were not covered in either the lecture or the colloquium.