Embeddings of Riemannian Manifolds with Finite Eigenvector Fields of   Connection Laplacian
  We study the problem asking if one can embed manifolds into finite dimensional Euclidean spaces by taking finite number of eigenvector fields of the connection Laplacian. This problem is essential for the dimension reduction problem in massive data analysis. Singer-Wu proposed the vector diffusion map which embeds manifolds into the Hilbert space $l^2$ using eigenvectors of connection Laplacian. In this paper, we provide a positive answer to the problem. Specifically, we use eigenvector fields to construct local coordinate charts with low distortion, and show that the distortion constants depend only on geometric properties of manifolds with metrics in the little H\"{o}lder space $c^{2,\alpha}$. Next, we use the coordinate charts to embed the entire manifold into a finite dimensional Euclidean space. The proof of the results relies on solving the elliptic system and provide estimates for eigenvector fields and the heat kernel and their gradients. We also provide approximation results for eigenvector field under the $c^{2,\alpha}$ perturbation. 
Chen-Yun Lin and Hau-Tieng Wu
math.DG math.SP