Deep Neural Network Approximation
Deep neural network (DNN) approximation focuses on understanding and improving the ability of DNNs to accurately represent complex functions, particularly in high dimensions where traditional methods struggle. Current research investigates optimal approximation rates for various function classes (e.g., oscillatory, Hölder-continuous, and those with specific symmetries) using different activation functions and network architectures, including multi-grade deep learning models and those incorporating gradient information. These advancements are crucial for improving the efficiency and accuracy of DNNs in diverse applications, ranging from solving partial differential equations and integral equations to image processing and scientific computing.