Special Session 17: Analysis of chemotaxis models

Cross-diffusion system with doubly degenerate nonlinear diffusion and strong chemotactic effect
Bao-Ngoc Tran
University of Graz
Austria
Co-Author(s):    Juan Yang
Abstract:
Motivated by the study of bacteria`s response to environmental conditions, we consider the doubly degenerate nutrient taxis system governed by $ u_t = \nabla \cdot ( uv \nabla u) - \nabla\cdot (u^{\alpha} v\nabla v) + uv$ and $ v_t = \Delta v - u v$, where $\alpha \in [0,2]$ is the bacterial response parameter. Global weak solvability is highly challenging due to both the doubly degenerate diffusion and the strong chemotactic effect; we establish this for $0 \leq \alpha < 2$, see https://arxiv.org/pdf/2508.03268.