Executive Summary : | The project aims to conduct theoretical studies of living liquid crystals (LLCs), a class of fluids with active matter (AM) in them. AM, the collective motion of self-propelled organisms, has gained significant attention due to its intrinsic out-of-equilibrium behavior. Examples of AM include bacterial colonies, cytoskeleton biopolymers, phoretically propelled particles, vibrated granular matter, and artificial swimmers. Most studies have focused on AM in isotropic Newtonian fluids, where local particles swim parallel to each other. However, on a global scale, this orientational order is unstable, resulting in chaotic patterns of spatial alignment and velocities. LLCs are classical examples of anisotropic materials with long-range orientational ordering, with special directions of averaged molecular alignment called directors. Their mechanical, optical, and diffusive properties exhibit strong directional dependence. It is believed that LLCs will eventually create new microfluidic devices that can freely transport fluids without pumps or pressure, or create synthetic systems resembling cells moving freely. The project aims to develop theoretical frameworks by choosing suitable models of LCs and AM, introducing coupling terms that respect the symmetries of the individual systems and are consistent with experimental observations. Subsequent studies will focus on pattern formation of active and nematic components on this coupled two-component system, studying the effect of LC textures on transport properties of active particles, erasure of topological defects in LCs via active particle dynamics, and establishing command over active particle trajectories via tailored defects in LCs using boundary conditions.
The project aims to initiate new experimental and theoretical investigations in this exciting class of active non-Newtonian fluids. |