Numerical Methods and Approximation Techniques for Complex Systems

Report on Current Developments in the Research Area

General Direction of the Field

The recent developments in the research area are marked by a significant advancement in the application of numerical methods and approximation techniques to complex physical and biological systems. The field is moving towards more sophisticated and efficient computational approaches, particularly in the context of partial differential equations (PDEs) and their applications in various domains.

One of the key trends is the extension of traditional numerical methods to novel settings, such as surface PDEs and nonlinear poroelasticity. Researchers are developing new approximation methods that not only enhance the applicability of these techniques but also ensure their convergence and robustness. This is particularly evident in the development of threshold dynamics algorithms for surface-constrained interfacial motions, which are being advanced through the use of minimizing movements and generalized algorithms like MBO and HMBO.

Another notable direction is the refinement of finite element methods (FEM) for complex systems, such as those involving stress-dependent permeability in poroelasticity. The focus here is on creating robust, conservative, and adaptive methods that can handle the intricacies of nonlinear systems. This includes the development of a priori and a posteriori error bounds, which are crucial for ensuring the accuracy and reliability of numerical solutions.

In the biological realm, there is a growing interest in mathematical modeling of molecular motors and their role in cellular dynamics, such as flagellar activation. These models, often based on coupled systems of PDEs, are being rigorously analyzed for existence, uniqueness, and bifurcation properties, with numerical simulations providing further insights.

Lastly, the field is witnessing advancements in large-scale computational methods, such as the Method of Fundamental Solutions (MFS), which are being optimized for problems involving large collections of objects. These methods are being tailored to handle complex problems in elastance and mobility, with a focus on scalability and efficiency, particularly in the context of large suspensions and complex fluid applications.

Noteworthy Papers

  • Approximation and application of minimizing movements for surface PDE: This work significantly extends the applicability of minimizing movements to surface PDEs, enabling the approximation of multiphase, volume-preserving, curvature flows on surfaces via generalized MBO and HMBO algorithms.

  • A priori and a posteriori error bounds for the fully mixed FEM formulation of poroelasticity with stress-dependent permeability: The development of robust, conservative, and adaptive FEM methods for nonlinear poroelasticity, including a priori and a posteriori error estimates, marks a significant advancement in the field.

  • A Method of Fundamental Solutions for Large-Scale 3D Elastance and Mobility Problems: The scalable MFS formulations for large-scale 3D problems, particularly in elastance and mobility, demonstrate a new level of efficiency and accuracy, making them highly relevant for complex fluid applications.

Sources

Approximation and application of minimizing movements for surface PDE

A priori and a posteriori error bounds for the fully mixed FEM formulation of poroelasticity with stress-dependent permeability

Some mathematical models for flagellar activation mechanisms

A Method of Fundamental Solutions for Large-Scale 3D Elastance and Mobility Problems