Pattern Selection: Growth, Fronts, and Defects

该研究项目旨在通过直接建模和分析相干结构来数学描述物理和生物生长过程。特定的模型示例创建规则的图案，例如条纹或六边形点阵的斑点。这项研究的目标是找到模式的数学表征，解释这种规则模式在自然界中的普遍存在，同时为微观结构的自组织制造提供配方。该项目包括培训研究生和本科生的研究活动。该项目侧重于适用于没有技术上可行的空间动力学解释的系统的扰动方法，包括非局部和多维问题。它将探讨畴生长和图案形成的相互作用和运动前沿的速度选择机制。特别是，该研究的目的是开发技术的扰动和分岔问题的研究在无限维动力系统中的本质谱的存在下，使用严格的核心/远场分解。除了局部扰动分析，这些策略将在数值延拓算法中实现，具有先验和后验误差界。特别提出的目标是波数和模式的预测，在不断增长的领域，在模式形成系统中的入侵速度的表征，以及在非均匀介质中的脱钉渐近。

This research project aims to mathematically describe physical and biological growth processes through direct modeling and analysis of coherent structures. Particular model examples create regular patterns such as stripes or hexagonal lattices of spots. The goal of this research is to find mathematical characterizations of patterns that explain the ubiquity of such regular patterns across nature and, at the same time, to provide recipes for the self-organized manufacturing of microstructure. The project includes research activities that will train graduate and undergraduate students. The project focuses on perturbation methods that are applicable to systems without a technically viable spatial dynamics interpretation, including nonlocal and multi-dimensional problems. It will explore the interaction of the domain growth and pattern-formation and mechanisms of the speed-selection for traveling fronts. In particular, the research aims to develop techniques for the study of perturbation and bifurcation problems in infinite dimensional dynamical systems in the presence of essential spectrum using rigorous core/far-field decompositions. Beyond local perturbation analysis, these strategies will be implemented in numerical continuation algorithms, with a priori and a posteriori error bounds. Particular goals set forth are wavenumber and pattern predictions in growing domains, characterization of invasion speeds in pattern-forming systems, and depinning asymptotics in heterogeneous media.