Qualitative properties of solutions to a non-local free boundary problem modeling cell polarization

TL;DR

This paper studies a non-local free boundary problem modeling cell polarization, analyzing the conditions for support continuity and characterizing jumps in the free boundary based on initial data.

Contribution

It provides necessary and sufficient conditions for support continuity and characterizes free boundary jumps for a class of initial data.

Findings

Support continuity depends on initial data conditions.

Jumps in the free boundary occur when conditions are not met.

Complete characterization of boundary jumps for certain initial data.

Abstract

We consider a parabolic non-local free boundary problem that has been derived as a limit of a bulk-surface reaction-diffusion system which models cell polarization. The authors have justified the well-posedness of this problem and have further proved uniqueness of solutions and global stability of steady states. In this paper we investigate qualitative properties of the free boundary. We present necessary and sufficient conditions for the initial data that imply continuity of the support at $t = 0$. If one of these assumptions fail, then jumps of the support take place. In addition we provide a complete characterization of the jumps for a large class of initial data.