Confining a liquid crystal imposes topological constraints on theorientational order, allowing global control of equilibrium systems bymanipulation of anchoring boundary conditions. In this article, we investigatewhether a similar strategy allows control of active liquid crystals. We study ahydrodynamic model of an extensile active nematic confined in containers, withdifferent anchoring conditions that impose different net topological charges onthe nematic director. We show that the dynamics are controlled by a complexinterplay between topological defects in the director and their inducedvortical flows. We find three distinct states by varying confinement and thestrength of the active stress: a topologically minimal state, a circulatingdefect state, and a turbulent state. In contrast to equilibrium systems, wefind that anchoring conditions are screened by the active flow, preservingsystem behavior across different topological constraints. This observationidentifies a fundamental difference between active and equilibrium materials.
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