Self-organized multi-timescale dynamics in a confined active nematic*

Confining an active nematic suspension composed of microtubules and kinesin motor clusters to a disk below a critical diameter tames the otherwise turbulent flows observed in bulk into a single, system-sized vortex. This circulating flow is driven by two, topologically required +1/2 defects. In contrast to hydrodynamic theory, which predicts stable orbits, this state is periodically disrupted by boundary nucleation of a +/- 1/2 defect pair at a regular interval that is longer than the defect procession period. The nature of these slow periodic dynamics that are superimposed on the faster, procession dynamics will be the focus of this talk.