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arXiv · 2609.28160

Homological Trimming and Regularity of Filtrations via Local Obstruction Modules

Siddharth Pritam
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Abstract

Existing link-based combinatorial preprocessing methods speed up the computation of persistent homology by removing a vertex or edge only when its link remains a cone. We replace this condition with a quantitative homological certificate. The reduced homology of the filtered link of a generator (a vertex or edge) defines a local obstruction module whose future part describes the effect of deleting that generator. Its barcode certifies either exact deletion or an explicit bound on the bottleneck error, and a conflict colouring extends this guarantee to families of generators. Our implementation, HomTrim, removes an additional 13% to 41% of the input edges beyond domination-only preprocessing and reduces backend persistence time by factors ranging from 1.55 to 4.61 on weighted flag filtrations. The same module also yields regularity diagrams that measure how far a generator can move before becoming visible to homology, together with a multiscale stability result.

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Siddharth Pritam. 2026-09-23. Homological Trimming and Regularity of Filtrations via Local Obstruction Modules. https://arxiv.org/abs/2609.28160

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