Active matter under control

Active matter consumes fuel in order to sustain individual motion. This gives rise to interesting collective effects, such as motility induced phase separation, a hallmark of active matter. Currently, we lack a physical framework that predicts the best protocol for driving active systems between different states in a way that optimizes the dissipated energy. Indeed, existing equilibrium thermodynamics is an inadequate foundation to build a framework of control for active systems due to the constant consumption of fuel. Here, we derive and implement a nonequilibrium thermodynamic framework, using response theory, to optimally control active systems.