English

When do Keller-Segel systems with heterogeneous logistic sources admit generalized solutions?

Analysis of PDEs 2020-12-08 v1

Abstract

We construct global generalized solutions to the chemotaxis system \begin{align*} \begin{cases} u_t = \Delta u - \nabla \cdot (u \nabla v) + \lambda(x) u - \mu(x) u^\kappa,\\ v_t = \Delta v - v + u \end{cases} \end{align*} in smooth, bounded domains ΩRn\Omega \subset \mathbb R^n, n2n \geq 2, for certain choices of λ,μ\lambda, \mu and κ\kappa. Here, inter alia, the selections μ(x)=xα\mu(x) = |x|^\alpha with α<2\alpha < 2 and κ=2\kappa = 2as well as μμ1>0\mu \equiv \mu_1 > 0 and κ>min{2n2n,2n+4n+4}\kappa > \min\{\frac{2n-2}{n}, \frac{2n+4}{n+4}\} are admissible (in both cases for any sufficiently smooth λ\lambda). While the former case appears to be novel in general, in the two- and three-dimensional setting, the latter improves on a recent result by Winkler (Adv. Nonlinear Anal. 9 (2019), no. 1, 526-566), where the condition κ>2n+4n+4\kappa > \frac{2n+4}{n+4} has been imposed. In particular, for n=2n = 2, our result shows that taking any κ>1\kappa > 1 suffices to exclude the possibility of collapse into a persistent Dirac distribution.

Keywords

Cite

@article{arxiv.2004.02153,
  title  = {When do Keller-Segel systems with heterogeneous logistic sources admit generalized solutions?},
  author = {Jianlu Yan and Mario Fuest},
  journal= {arXiv preprint arXiv:2004.02153},
  year   = {2020}
}

Comments

16 pages

R2 v1 2026-06-23T14:39:46.029Z