On $\ell_p$-Vietoris-Rips complexes
Sergei O. Ivanov, Xiaomeng Xu
TL;DR
This paper unifies the ell_p-Vietoris-Rips theory across all p in [1,∞] through distance-matrix norms, connecting VR simplicial sets and complexes with blurred magnitude homology. It develops a general ν-VR framework, proving a stability theorem for persistent homology, a manifold-level homotopy equivalence at small scales for geodesic spaces, and invariance under metric completion, while showing that zero-scale limit homology is independent of p and commutes with filtered colimits. The work also introduces pro-simplicial-set perspectives, demonstrates commutation with filtered colimits for strict VR, and extends classical results (e.g., Hausmann) to the ν-setting, including explicit computations on spheres and circles. Together, these results enhance theoretical guarantees for topological data analysis using generalized VR constructions and provide a cohesive bridge between VR theory and magnitude homology via a broad, axiomatic norm-based framework.
Abstract
We study the concepts of the $\ell_p$-Vietoris-Rips simplicial set and the $\ell_p$-Vietoris-Rips complex of a metric space, where $1\leq p \leq \infty.$ This theory unifies two established theories: for $p=\infty,$ this is the classical theory of Vietoris-Rips complexes, and for $p=1,$ this corresponds to the blurred magnitude homology theory. We prove several results that are known for the Vietoris-Rips complex in the general case: (1) we prove a stability theorem for the corresponding version of the persistent homology; (2) we show that, for a compact Riemannian manifold and a sufficiently small scale parameter, all the "$\ell_p$-Vietoris-Rips spaces" are homotopy equivalent to the manifold; (3) we demonstrate that the $\ell_p$-Vietoris-Rips spaces are invariant (up to homotopy) under taking the metric completion. Additionally, we show that the limit of the homology groups of the $\ell_p$-Vietoris-Rips spaces, as the scale parameter tends to zero, does not depend on $p$; and that the homology groups of the $\ell_p$-Vietoris-Rips spaces commute with filtered colimits of metric spaces.
