Hydrodynamics of random-organizing hyperuniform fluids

Recently, an exotic hyperuniform fluid state was found in a number of nonequilibrium systems, which shows the promise for fabrication of novel lifelike functional materials capable of self-healing and self-adapting. However, the general mechanism of fluidic hyperuniformity (HU) and its fundamental difference from equilibrium fluids remain unclear, which hinders the rational design of nonequilibrium hyperuniform fluids. In this work, we propose a nonequilibrium hard-sphere model of hyperuniform fluids and formulate a full hydrodynamic description based on the generalized Navier-Stokes equations. Our theory reveals the mechanism of fluidic HU in a simple and intuitive way, which is confirmed by simulating a realistic active spinner system.