Towards a theoretical foundation for Laplacian-based manifold methods

In recent years manifold methods have attracted a considerable amount of attention in machine learning. However most algorithms in that class may be termed "manifold-motivated" as they lack any explicit theoretical guarantees. In this paper we take a step towards closing the gap between theory and practice for a class of Laplacian-based manifold methods. We show that under certain conditions the graph Laplacian of a point cloud converges to the Laplace-Beltrami operator on the underlying manifold. Theorem 1 contains the first result showing convergence of a random graph Laplacian to manifold Laplacian in the machine learning context.