Bi-Lipschitz embeddings revisited
H. Movahedi-Lankarani, R. Wells
TL;DR
The paper investigates when the distance-to-point map $\iota_d:(X,d)\to L^2(\mu)$ can be used to obtain bi-Lipschitz embeddings of compact metric-measure spaces into finite-dimensional Euclidean spaces. It analyzes the canonical map, its radial projection, and associated metrics $\rho_d$ and $\theta_d$, establishing three concrete embedding criteria (via $\iota_{\rho_d}$, near-isometric behavior, and $\iota_{\Delta(d)}$) that guarantee a bi-Lipschitz embedding into some $\mathbb{R}^N$. Key contributions include three embedding theorems, a detailed examination of auxiliary maps and spherical compactness notions, and an erratum to a prior result (bilip) clarifying the required hypotheses. The results provide explicit, verifiable criteria for embedding compact metric-measure spaces into Euclidean spaces, with potential applications in geometric analysis and data representation, and connect canonical distance-function embeddings to broader concepts like Kał-doubling and spherical compactness.
Abstract
Given a metric space (X, d), we continue our study of the distance function x\mapsto d(x,-) and its relation to bi-Lipschitz embeddings of (X, d) into R^N. As application, given a compact metric-measure space (X, d,μ), we give three sufficient conditions for the existence of such a bi-Lipschitz embedding.
