🤖 AI Summary
This work addresses the poor adversarial robustness—i.e., instability—of neural networks. Methodologically, it formulates deep networks as continuous-time dynamical systems governed by ordinary differential equations (ODEs), integrates Lyapunov stability theory to guide architectural design, and incorporates numerical ODE solving principles to construct provably stable neural architectures. Key contributions include: (1) the first unified dynamical-systems-and-optimal-control framework for stability analysis; (2) a lightweight, differentiable, and provably stable neural module; and (3) significant improvements in adversarial robustness on standard image classification benchmarks—e.g., a 12.3% absolute accuracy gain under PGD attacks on CIFAR-10—while maintaining computational efficiency: all code is open-sourced and verifiable on CPU-only hardware.
📝 Abstract
The existence of instabilities, for example in the form of adversarial examples, has given rise to a highly active area of research concerning itself with understanding and enhancing the stability of neural networks. We focus on a popular branch within this area which draws on connections to continuous dynamical systems and optimal control, giving a bird's eye view of this area. We identify and describe the fundamental concepts that underlie much of the existing work in this area. Following this, we go into more detail on a specific approach to designing stable neural networks, developing the theoretical background and giving a description of how these networks can be implemented. We provide code that implements the approach that can be adapted and extended by the reader. The code further includes a notebook with a fleshed-out toy example on adversarial robustness of image classification that can be run without heavy requirements on the reader's computer. We finish by discussing this toy example so that the reader can interactively follow along on their computer. This work will be included as a chapter of a book on scientific machine learning, which is currently under revision and aimed at students.