On a comparison method for a parabolic-elliptic system of chemotaxis with density-suppressed motility and logistic growth

Abstract

We consider a parabolic-elliptic system of partial differential equations with chemotaxis and logistic growth given by the system $$ \left\{ \begin{array}{l} u_t -\Delta (u \gamma(v)= \mu u(1-u), \\ - \Delta v +v=u, \end{array} \right. $$ under Neumann boundary conditions and appropriate initial data in a bounded and regular domain $\Omega$ of $\R^N$ (for $N \geq 1)$, where $\gamma \in C^3([0, \infty))$ and satisfies the assumptions $\gamma (s) > 0$, $\gamma^{\prime}(s) \leq 0$, $\gamma^{\prime \prime} (s) \geq 0$, $\gamma^{\prime \prime \prime}(s) \leq 0$ for any $s \geq 0$ $$-2 \gamma^{\prime}(s) + \gamma^{\prime \prime}(s)s \leq \mu_0< \mu$$ $$\frac{[\gamma^{\prime}(s)]^2}{\gamma(s)} \leq c, \quad \mbox{ for any } s \in [0, \infty). $$ We obtain the global existence and uniqueness of bounded in time solutions and the following asymptotic behavior $$\|u- 1\|_{L^{\infty}(\Omega)} +\|v- 1\|_{L^{\infty}(\Omega)} \rightarrow 0, \quad \mbox{ when } t \rightarrow +\infty.$$