Lecture Notes on Proliferating Active Matter#
These lecture notes are a brief summary of four lectures given in the first week of the 2023 Les Houches workshop on Proliferating Active Matter, broadly interpreted.
Active Matter is concerned matter that is constantly pushed out of equilibrium by local injection of energy. Energy injection is usually implemented by some kind of mechanical engine converting available (chemical) free energy into mechanical energy. For example, motors or janus particles actuated by light.
These types of active matter break time reversal symmetry, but conserve particle numbers. However, a special kind of activity is replication and its flipside death, which are a hallmark of life. Here, we focus on some of the major consequences of replication, as it breaks particle conservation, injects mutations fueling evolutionary processes, within simple models. After an introduction to the different types of PAM, we discuss general patterns present even in toy models, which one could write down without getting out of your armchair. In later parts, we increase realism somewhat by considering the actual physics of soft matter systems. While we only need few biolgical facts, the reader is strongly encouraged to get inspired by thy actual dynamics of living and growing systems, as captured for example in the amazing time-lapse movies of Wim van Egmond.