SKM 2023 – wissenschaftliches Programm
DY 42.8: Poster
Donnerstag, 30. März 2023, 13:00–16:00, P1
Thermodynamics of active matter systems under coarse graining — •Robin Bebon and Thomas Speck — Institute for Theoretical Physics 4, University of Stuttgart, Heisenbergstraße 3, 70569 Stuttgart, Germany
Over the last decade, dynamic field theories have proven useful in the description of collective behavior and large-scale dynamics of active matter systems. However, despite their popularity, surprisingly little is known about how to capture thermodynamics on the level of such hydrodynamic descriptions. This is partially due to the fact that common approaches, based on symmetry arguments and conservation laws, typically neglect degrees of freedom that play a crucial role in quantifying the system’s energetics, e.g., the self-propulsion mechanism. To advance, we propose a bottom-up approach that starts with a thermodynamically consistent microscopic model of catalytic particles driven by a constant affinity and derive effective hydrodynamic equations via explicit coarse graining. To ensure that information of the self-propulsion mechanism and its energy consumption is preserved on the macro-scale, we introduce an additional field, which for the considered model tracks the local rate of successful chemical events. We find that, near equilibrium, particle current and chemical field couple linearly through their respective thermodynamic forces, closely resembling linear irreversible thermodynamics. This provides an access point to investigate the thermodynamic properties of our field theory and compare the results with their microscopic counterparts.