Do active matter systems obey thermodynamic (-like) laws?

Active matter consists of particles which continuously dissipate energy to generate self-propelled motion.

Microscopic such particles (e.g., bacteria or synthetic Janus colloids) are typically swimming through an aqueous solution at room temperature. Active particle systems therefore constitute soft matter systems in an inherent out-of-equilibrium state.

Neverthless, the collective behavior emerging from the interplay of active swimming and thermal fluctuations bears staggering resemblance with thermodynamic states of equilibrium systems.Inspired by these observations, the visionary goal is to devise a general thermodynamic (-like) framework which characterizes states, phases and processes in active matter systems.

Apart form its appeal from a basic science perspective, this quest is inspired by the predictive power such a theory would have to guide the micro- and nano-technological development of "smart micro-devices" fabricated from active matter, which autonomously perform specific tasks, e.g., in personalized health care.The present project contributes to this problem by investigating "activity-induced" transport phenomena and mechanical properties in active matter, and to exploit the resulting insights to assess if and how a thermodynamic theory of active matter may be developed.

The active particles are modeled and analyzed using the tools of non-equilibrium statistical physics and stochastic thermodynamics, analytical studies are combined with numerical simulations.