Simulations of Elastic Active Matter*

Active matter encompass a wide range of non-equilibrium systems in which the constituents can convert other forms of energy into mechanical work. Active matter can give rise to intriguing phenomena that do not arise in equilibrium systems. One example is collective dynamics, which have been extensively examined in terms of swarming, flocking and spontaneous flows in active fluids. In this work, we rely on particle-based simulations to investigate the elastic properties of active matter. We find two activity-driven elastic modes in a two-dimensional system.  Our calculations are complemented by theoretical analyses and exhibit excellent agreement with bacteria-based experiments. Our results uncover the physics of the collective dynamics in active solids, deepening our understanding of active matter.