Vector-Valued Gaussian Processes for Approximating Divergence- or Rotation-free Vector Fields
Quoc Thong Le Gia, Ian Hugh Sloan, Holger Wendland
TL;DR
This work develops a rigorous framework for vector-valued Gaussian processes focused on divergence-free or curl-free vector fields. It extends GP theory to Hilbert-space valued functions, introduces divergence-free and curl-free matrix-valued kernels, and connects these to vector-valued reproducing kernel Hilbert spaces and Sobolev spaces, including extension/restriction results. The authors provide comprehensive Sobolev-space error analyses for the predictive mean under both interpolation (noise-free) and approximation (noisy) regimes, with explicit rates governed by fill distance, mesh ratio, and smoothness indices. The results supply concrete convergence guarantees and kernel-design guidance for physically constrained vector-field reconstruction in applications such as incompressible fluid dynamics and electromagnetic modeling.
Abstract
In this paper, we discuss vector-valued Gaussian processes for the approximation of divergence- or rotation-free functions. We establish the theory for such Gaussian processes, then link the theory to multivariate approximation theory, and finally give error estimates for the predictive mean in various situations.
