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arXiv · 2610.30837

A homological approach to Dax invariants

Jae Choon Cha
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Abstract

We present a homological construction of Dax invariants in 4-manifolds that is intrinsic to the topological category and requires neither smoothing nor generic representatives. Applications include an extension of the invariant of Cha-Kim to neat disks without assuming local flatness, and a topological definition of the Dax map for arc spaces that yields a short alternative proof of the topological Dax isomorphism theorem.

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Jae Choon Cha. 2026-10-22. A homological approach to Dax invariants. https://arxiv.org/abs/2610.30837

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