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arXiv · 2506.15482

Isolated singularities in $G_2$-structures with torsion

Henrique Sá Earp·Jakob Stein
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Abstract

We revisit the study of $G_2$-structures with special torsion, and isolated singularities. Many of the known examples with conical singularities admit additional symmetries, and we describe circle-invariant $G_2$-structures in this context. Finally, we show that collapsing the circle fibres of a contact Calabi-Yau manifold at isolated points cannot produce a $G_2$-structure with bounded torsion.

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Henrique Sá Earp, Jakob Stein. 2025-06-18. Isolated singularities in $G_2$-structures with torsion. https://doi.org/10.1007/s10711-026-01082-1

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