Orientational order and mechanical self-organization

When elongated cells such as rod-shaped bacteria grow and divide, they generate both mechanical forces and orientational patterns. The feedback between cell shape, growth-driven flows, and mechanical interactions produces self-organization that standard continuum active-nematic theories fail to capture.

Using large-scale agent-based simulations we showed that confined growing rods can reach perfect global alignment, driven by growth-induced stress anisotropy, and that a subtle detail — the tip shape of a cell — is decisive for the resulting microdomain structure. We are now mapping how confinement geometry and the inheritance of division axes can be used to predict and control orientational order.

These results also point beyond biology, toward the design of self-replicating materials with programmable mechanical textures.