Soft matter

In this course, we introduce the major concepts of soft condensed matter, with a focus on fluid interfaces. Soft condensed matter can be defined as the wide class of complex fluids that exhibit multi-hierarchical structural organization spanning the molecular scale up to the macroscopic scale. These complex fluids present unconventional (even paradoxical) physical properties that emerges due to coupling processes between these different length scales. For instance, mixing air and water (with surfactants) produces an aqueous foams which, although it is solely constituted of fluid phases, behaves as a solid phase that can “melt” under a small mechanical load.

The development of animals, starting from a single cell to produce a fully formed organism, is a fascinating process. Its study is currently advancing at a rapid pace thanks to combined experimental and theoretical progress, with yet many fundamental questions remaining to be understood. 

This course will address the fundamental theoretical concepts underlying the self-organization of multicellular systems, from genetic regulation to the mechanics of active biological materials. The course will be based on various concepts of theoretical physics: dynamical systems, soft an active matter, mechanics of continuous media, numerical modeling, etc.

Computational physics plays a central role in all fields of physics, from classical statistical physics, soft matter problems, and hard-condensed matter. Our goal is to cover the very basic concepts underlying computer simulations in classical and quantum problems, and connect these ideas to relevant contemporary research problems in various fields of physics. In the TD’s you will also learn how to set, perform and analyse simple computer simulations by yourself. We will use Python, but no previous knowledge of this programming language is needed.

The lectures offer a statistical-physics perspective on active matter, which encompasses systems whose fundamental constituents dissipate energy to exert forces on the environment. This out-of-equilibrium microscopic drive endows active systems with properties unmatched in passive ones. From molecular motors to bacteria and animals, active agents are found at all scales in nature. Over the past twenty years, physicists and chemists have also engineered synthetic active systems in the lab, by motorizing particles whose sizes range from nanometers to centimeters, hence paving the way towards the engineering of active materials.

The lectures will rely on the modern tools of statistical mechanics, from stochastic calculus to field theoretical methods, using both theoretical models and experimental systems to illustrate the rich physics of active matter.