Extended Data Fig. 5: Generation of train waves by forced synchronization of oscillators in the nonreciprocal coupled oscillator model with a full nonreciprocity ε = 1.
From: Emergence of large-scale mechanical spiral waves in bacterial living matter
The simulation was performed in a system with pre-existing propagating spiral waves (left panel, T = 2400 s). Starting from T = 2408 s, the oscillators near the left boundary were forced to synchronize and remained synchronized throughout the rest of the simulation, which simulated the application of a filter disk infused with drugs that trigger pilus retraction. Following the forced synchronization, train waves emanated from near the left boundary and propagated along a direction perpendicular to the boundary (right panel, T = 4000 s and T = 16000 s). The train waves gradually replaced the existing spiral waves. Also see Methods and Movie 8. The results reproduce the experimental phenomena in Movie 5 and Movie 6, supporting the notion that train waves observed in the experiments were due to forced synchronization of the pilus retraction-extension cycle.
