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arXiv · 2404.11679

Quantitative metric density and connectivity for sets of positive measure

Guy C. David·Brandon Oliva
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Abstract

We show that in doubling, geodesic metric measure spaces (including, for example, Euclidean space), sets of positive measure have a certain large-scale metric density property. As an application, we prove that a set of positive measure in the unit cube of $\mathbb{R}^d$ can be decomposed into a controlled number of subsets that are "well-connected" within the original set, along with a "garbage set" of arbitrarily small measure. Our results are quantitative, i.e., they provide bounds independent of the particular set under consideration.

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Guy C. David, Brandon Oliva. 2024-04-17. Quantitative metric density and connectivity for sets of positive measure. https://arxiv.org/abs/2404.11679

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