论文标题

Gierer-Meinhardt模型的局部3-D点模式的渐近分析:存在,线性稳定性和缓慢的动力学

An Asymptotic Analysis of Localized 3-D Spot Patterns for Gierer-Meinhardt Model: Existence, Linear Stability and Slow Dynamics

论文作者

Gomez, Daniel, Ward, Michael J., Wei, Juncheng

论文摘要

局部斑点模式,其中一个或多个溶液组分集中在域中的某些点上,是反应扩散系统的一类局部模式,它们在广泛的建模场景中出现。在任意界限的3-D结构域中,分析了众所周知的奇异扰动的Gierer-Meinhardt(GM)激活剂抑制剂系统的局部多点模式的存在,线性稳定性和缓慢的动力学,在小型激活剂扩散剂扩散剂$ \ varepsilon^2 \ ll ll 1 $ 1 $ 1 $中。我们的主要重点是针对抑制剂扩散性的不同渐近范围$ d $对不同类型的多点模式进行分类,并预测其线性稳定性。对于范围,$ d = {\ mathcal o}(\ varepsilon^{ - 1})\ gg 1 $,尽管可以构建对称和不对称的准e平衡点模式,但不对称模式被证明总是不稳定的。在$ d $的这一范围内,可以表明对称点模式可以进行竞争不稳定性或HOPF分叉,从而导致斑点歼灭或时间斑点振幅振荡。对于$ d = {\ mathcal o}(1)$,仅存在对称点quasi equilibria,并且它们在$ {\ Mathcal o}(1)$时间间隔上是线性稳定的。在此范围内,结果表明,斑点位置在$ {\ Mathcal O}(\ Varepsilon^{ - 3})$时尺度在其平衡位置的$ {\ Mathcal O}(\ varepsilon^{ - 3})上缓慢演变,该$ time time scale朝向其平衡位置,该梯度流由涉及减少波绿色功能的离散能量确定。特定核心问题的远场行为的核心作用是特征局部位点的特征,用于在$ d = {\ Mathcal O}(1)$和$ d = {\ Mathcal O}(\ varepsilon^{ - 1})$ semimes的属性属性的属性中,在$ d = {\ Mathcal o}(1)$和$ d = {\ Mathcal o}(\ Mathcal O}(\ Mathcal O}(\ Mathcal O}(\ Mathcal O}(\ Mathcal O})中

Localized spot patterns, where one or more solution components concentrates at certain points in the domain, are a common class of localized pattern for reaction-diffusion systems, and they arise in a wide range of modeling scenarios. In an arbitrary bounded 3-D domain, the existence, linear stability, and slow dynamics of localized multi-spot patterns is analyzed for the well-known singularly perturbed Gierer-Meinhardt (GM) activator-inhibitor system in the limit of a small activator diffusivity $\varepsilon^2\ll 1$. Our main focus is to classify the different types of multi-spot patterns, and predict their linear stability properties, for different asymptotic ranges of the inhibitor diffusivity $D$. For the range $D={\mathcal O}(\varepsilon^{-1})\gg 1$, although both symmetric and asymmetric quasi-equilibrium spot patterns can be constructed, the asymmetric patterns are shown to be always unstable. On this range of $D$, it is shown that symmetric spot patterns can undergo either competition instabilities or a Hopf bifurcation, leading to spot annihilation or temporal spot amplitude oscillations, respectively. For $D={\mathcal O}(1)$, only symmetric spot quasi-equilibria exist and they are linearly stable on ${\mathcal O}(1)$ time intervals. On this range, it is shown that the spot locations evolve slowly on an ${\mathcal O}(\varepsilon^{-3})$ time scale towards their equilibrium locations according to an ODE gradient flow, which is determined by a discrete energy involving the reduced-wave Green's function. The central role of the far-field behavior of a certain core problem, which characterizes the profile of a localized spot, for the construction of quasi-equilibria in the $D={\mathcal O}(1)$ and $D={\mathcal O}(\varepsilon^{-1})$ regimes, and in establishing some of their linear stability properties, is emphasized.

扫码加入交流群

加入微信交流群

微信交流群二维码

扫码加入学术交流群,获取更多资源