Global classical solutions, stability of constant equilibria, and spreading speeds in attraction-repulsion chemotaxis systems with logistic source on $\mathbb{R}^{N}$
We consider the following chemotaxis systems ⎩⎨⎧ut=Δu−χ1∇(u∇v1)+χ2∇(u∇v2)+u(a−bu),x∈RN,t>0,0=(Δ−λ1I)v1+μ1u,x∈RN,t>0,0=(Δ−λ2I)v2+μ2u,inx∈RN,t>0,u(⋅,0)=u0,x∈RN,where χi,λi,μi,i=1,2 and a,b are positive constant real numbers and N is a positive integer. Under some conditions on the parameters, we prove the global existence and boundedness of classical solutions (u(x,t;u0),v1(x,t;u0),v2(x,t;u0)) for nonnegative, bounded, and uniformly continuous initials u0(x). Next, we show that, for every strictly positive initial \,u0(x),t→∞lim[∥u(⋅,t;u0)−ba∥∞+∥λ1v1(⋅,t;u0)−baμ1∥∞+∥λ2v2(⋅,t;u0)−baμ2∥∞]=0. Finally, we explore the spreading properties of the global solutions and prove that there are two positive numbers 0<c−∗(χ1,μ1,λ1,χ2,μ2,λ2)<c+∗(χ1,μ1,λ1,χ2,μ2,λ2) such that for every nonegative initial u0(x) with nonempty and compact support, t→∞lim[∣x∣≤ctsup∣u(x,t;u0)−ba∣+∣x∣≤ctsup∣λ1v1(x,t;u0)−baμ1∣+∣x∣≤ctsup∣λ2v2(x,t;u0)−baμ2∣]=0whenever 0≤c<c−∗(χ1,μ1,λ1,χ2,μ2,λ2),\ andt→∞lim[∣x∣≥ctsup∣u(x,t;u0)∣+∣x∣≥ctsup∣v1(x,t;u0)∣+∣x∣≥ctsup∣v2(x,t;u0)∣]=0whenever c>c+∗(χ1,μ1,λ1,χ2,μ2,λ2). Furthermore we show that(χ1,χ2)→(0,0)limc−∗(χ1,μ1,λ1,χ2,μ2,λ2)=(χ1,χ2)→(0,0)limc+∗(χ1,μ1,λ1,χ2,μ2,λ2)=2a.
@article{arxiv.1612.00924,
title = {Global classical solutions, stability of constant equilibria, and spreading speeds in attraction-repulsion chemotaxis systems with logistic source on $\mathbb{R}^{N}$},
author = {Rachidi B. Salako and Wenxian Shen},
journal= {arXiv preprint arXiv:1612.00924},
year = {2017}
}