Three dimensional chiral active fluids at intermediate Reynolds numbers

We present an experimental system consisting of millimeter-size spinning magnetic particles suspended in a fluid that organize into a fluctuating lively three-dimensional steady state. We examine the emergence of this state from the dynamics of individual particles and pair-wise interactions all of which bear unique signatures of inertial dynamics of the background fluid. Combining experiments, numerical simulations and theoretical modeling, we reveal novel mechanisms for self propulsion, flocking and binding which form the dynamical building blocks of their collective behavior. Our research provides insight into how inertial effects can have a profound effect on active matter as well as providing a window into the dynamics of chiral active flows in three dimensions.