Special Session 17: Analysis of chemotaxis models

A critical parameter in a chemotaxis system with spatially heterogeneous chemotactic sensitivity
Gregor M Fluechter
Paderborn University
Germany
Co-Author(s):    
Abstract:
We study a parabolic-elliptic Keller-Segel system with spatially dependent chemotactic sensitivity of the form \begin{eqnarray*} \left\{ \begin{array}{l} u_t = \Delta u - \nabla \cdot (|x|^\alpha u\nabla v), \[1mm] 0 = \Delta v - \mu + u, \qquad \mu:=\frac{1}{|\Omega|} \int_{\Omega} u, \end{array} \right. \qquad \qquad (\star) \end{eqnarray*} for $\alpha>0$ under homogeneous Neumann boundary conditions in the ball $\Omega=B_R(0)\subset \mathbb R^n$. This model accounts for a reduction in chemotactic sensitivity in the vicinity of the origin. For radially symmetric initial data, we discuss the solvability of $(\star)$ and analyze the behavior of solutions with respect to global boundedness and finite-time blow-up.