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Smooth atlas with identity transitions on blowups of locally ordered precubical realizations

Establish the existence of a smooth atlas on the blowup \tilde{|P|_{lo}} of the locally ordered realization |P|_{lo} of any precubical set P—where the blowup is the euclidean local order formed by germs of n-dimensional traversals that contain their base point—with the property that every chart transition map on overlaps is the identity map.

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Background

The paper constructs, via sheaf-theoretic methods, the blowup \tilde{X} of a locally ordered space X as a euclidean local order whose points are germs of n-dimensional traversals containing their base point, and shows a universal lifting property for local embeddings. For locally ordered realizations of precubical sets, they provide charts in examples where transition maps are identities and give a combinatorial description of the blowup.

In the conclusion, the authors aim to extend metric constructions from prior work on non-Hausdorff manifolds over graph products by equipping the blowup of locally ordered realizations of precubical sets with a smooth atlas. They explicitly conjecture that such an atlas can be chosen so that all chart transitions are identity maps, which would greatly simplify smooth structure and may facilitate defining a pseudometric reflecting execution times of program traces.

References

In this paper, we have only defined a locally ordered manifold structure on the blowup, but as suggested in the introduction, it should not be very hard to get a smooth atlas in the case of locally ordered realizations of precubical sets (we even conjecture the existence of an atlas whose related transition maps are identities).

Non-Hausdorff manifolds over locally ordered spaces via sheaf theory (2505.12087 - Chamoun et al., 17 May 2025) in Conclusion