Defects in an Active Nematic Confined to a Toroid

Active materials are driven far from the ground state by the motion of their constituent particles, thereby making them inherently non-equilibrium materials. For an active nematic, this results in a continuous creation and annihilation of ±1/2 defect pairs. Here, we confine an active nematic to the surface of a toroid and focus on how the defect density and defect orientation couple to the curvature of the underlying surface.