Possible points of blow-up in chemotaxis systems with spatially heterogeneous logistic source

Abstract

We discuss the influence of possible spatial inhomogeneities in the coefficients of logistic source terms in parabolic-elliptic chemotaxis-growth systems of the form \begin{align*} u_t &= Δu - \nabla\cdot(u\nabla v) + κ(x)u-μ(x)u^2, 0 &= Δv - v + u \end{align*} in smoothly bounded domains $\Omega \subset {\mathbb{R}}^2$. Assuming that the coefficient functions satisfy $\kappa ,\mu \in C^0(\overline{\Omega })$ with $\mu \ge 0$ we prove that finite-time blow-up of the classical solution can only occur in points where $\mu$ is zero, i.e.\ that the blow-up set $\mathcal{B}$ is contained in \begin{align*} \big\{x\in\overlineΩ\midμ(x)=0\big\}. \end{align*} Moreover, we show that whenever $\mu (x_0)>0$ for some $x_0\in \overline{\Omega }$, then one can find an open neighbourhood $U$ of $x_0$ in $\overline{\Omega }$ such that $u$ remains bounded in $U$ throughout evolution.

15 pages

References in corpus (2)

• Approaching optimality in blow-up results for Keller-Segel systems with logistic-type dampening
• Global existence of solutions to Keller-Segel chemotaxis system with heterogeneous logistic source and nonlinear secretion

Cited by in corpus (2)

• Corners and collapse: Some simple observations concerning critical masses and boundary blow-up in the fully parabolic Keller-Segel system
• Location of blow-up points in fully parabolic chemotaxis systems with spatially heterogeneous logistic source