Alpha shapes and optimal transport on the sphere

Erik Carlsson; Greg DePaul

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arXiv · 2412.04286

Alpha shapes and optimal transport on the sphere

Erik Carlsson·Greg DePaul

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Abstract

In [3], the authors used the Legendre transform to give a tractable method for studying Topological Data Analysis (TDA) in terms of sums of Gaussian kernels. In this paper, we prove a variant for sums of cosine similarity-based kernel functions, which requires considering the more general "$c$-transform" from optimal transport theory [16]. We then apply these methods to a point cloud arising from a recent breakthrough study, which exhibits a toroidal structure in the brain activity of rats [11]. A key part of this application is that the transport map and transformed density function arising from the theorem replace certain delicate preprocessing steps related to density-based denoising and subsampling.

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Erik Carlsson, Greg DePaul. 2024-12-05. Alpha shapes and optimal transport on the sphere. https://arxiv.org/abs/2412.04286

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