Extended Data Fig. 10: Coexistence of two global motion modes in modelled active solid under isotropic lateral confinement.

(a,b) Temporal dynamics of collective velocity of the system where oscillatory translation and oscillatory rotation modes co-existed with identical frequencies (\({f}_{t}={f}_{r}=0.10\); panel a) or with the frequency of the oscillatory translation mode doubled (\({f}_{t}=0.13\), \({f}_{r}=0.07\); panel b). The collective velocity was averaged over all particles in the simulation and then decomposed as Cartesian (yellow and blue traces; upper part of each panel) and polar-coordinate components (red: tangential or azimuthal component, green: radial component; lower part of each panel). Simulation parameters: panel a, \({v}_{0}=5,{k}_{b}=12\); panel b, \({v}_{0}=9,{k}_{b}=16\); the ratios between k_b, k_s and k_r are fixed (Methods). (c,d) Panels c and d display the trajectory of representative particles in the simulations analysed in panels a and b, respectively. In each panel the particle was chosen at ~5 times of the equilibrium interparticle distance from the centre of the circular simulation domain (black dot) at different polar angles. The trajectories were brought close to the centre for better visualization, and thus the scale bars (indicating 1/3 interparticle distance at equilibrium) apply to the trajectories only. Colour map indicates time.