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arXiv · 2606.29491

Geometry of $D_4^-$-front singularities and a Gauss-Bonnet type formula

Kentaro Saji
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Abstract

We construct a form of the $D_4^-$-singularity of fronts in $\R^3$ which uses coordinate transformation on the source and isometry on the target. As an application, we compute differential geometric invariants near the $D_4^-$-singularity, and give a Gauss-Bonnet type theorem for one-parameter generic fronts.

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Kentaro Saji. 2026-06-28. Geometry of $D_4^-$-front singularities and a Gauss-Bonnet type formula. https://arxiv.org/abs/2606.29491

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