A Sheaf-Theoretic Construction of Shape Space
Abstract
We present a sheaf-theoretic construction of shape space -- the space of all shapes. We do this by describing a homotopy sheaf on the poset category of constructible sets, where each set is mapped to its Persistent Homology Transform (PHT). Recent results that build on fundamental work of Schapira have shown that this transform is injective, thus making the PHT a good summary object for each shape. Our homotopy sheaf result allows us to "glue" PHTs of different shapes together to build up the PHT of a larger shape. In the case where our shape is a polyhedron we prove a generalized nerve lemma for the PHT. Finally, by re-examining the sampling result of Smale-Niyogi-Weinberger, we show that we can reliably approximate the PHT of a manifold by a polyhedron up to arbitrary precision.
Cite
@article{arxiv.2204.09020,
title = {A Sheaf-Theoretic Construction of Shape Space},
author = {Shreya Arya and Justin Curry and Sayan Mukherjee},
journal= {arXiv preprint arXiv:2204.09020},
year = {2023}
}
Comments
Version 3 has 45 pages and 11 figures. Substantially revised to include more background material and explicit computations of PHT distances between point clouds. A new appendix presents out gluing result for the PHT from the infinity category point of view