Topology and morphology of self-deforming active shells

TL;DR

This paper introduces a comprehensive model for active shells that incorporates particle orientation, hydrodynamics, and active stresses, revealing how self-induced flows and defects influence shape transformations relevant to biological and material systems.

Contribution

It provides a novel framework integrating active matter dynamics with shell morphology, highlighting the role of topological defects in shape control.

Findings

Active stresses can be tuned to control shell conformations.

Self-induced flows influence morphological dynamics.

Topological defects guide morphogenesis.

Abstract

We present a generic framework for modelling three-dimensional deformable shells of active matter that captures the orientational dynamics of the active particles and hydrodynamic interactions on the shell and with the surrounding environment. We find that the cross-talk between the self-induced flows of active particles and dynamic reshaping of the shell can result in conformations that are tunable by varying the form and magnitude of active stresses. We further demonstrate and explain how self-induced topological defects in the active layer can direct the morphodynamics of the shell. These findings are relevant to understanding morphological changes during organ development and the design of bio-inspired materials that are capable of self-organisation.