Liquid crystals and topological vorticity: smoothness of mild solutions

TL;DR

This paper introduces new PDE models for liquid crystal flow incorporating topological vorticity, achieving regularity results for mild solutions and linking to models of magnetic materials.

Contribution

It presents novel models that integrate topological vorticity effects into liquid crystal dynamics and proves regularity of solutions under natural initial conditions.

Findings

Regularity of mild solutions under natural assumptions

Models capturing Navier-Stokes features with scalar unknowns

Connections with ferromagnet models

Abstract

We introduce several new models whose common feature is to take into account effects from topological vorticity. The macroscopic unknown is driven by a dissipative anomalous diffusion (of SQG-type) and is coupled with the orientation of the crystal, moving by the gradient flow of the energy of maps. The main idea of such models is to have a better insight on the vorticity formulation of the Liquid Crystal Flow and to tackle some regularity issues in the associated conserved geometric motions. One of the advantage of the present PDEs is to capture features of the Navier-Stokes equations (or Euler) through a {\sl scalar} unknown, keeping the advection-diffusion structure of the orientation field. We obtain regularity for mild solutions under natural assumptions for the initial data, which are actually near-optimal. Along the way, we also draw some links with natural models of (anti-)ferromagnets previously investigated.