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arXiv · 2601.20813

New Solutions to the $G_2$ Hull-Strominger System via torus fibrations over $K3$ orbifolds

Anna Fino·Gueo Grantcharov·Jose Medel
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Abstract

Using torus fibrations over K3 orbisurfaces, we construct new smooth solutions to the $G_2$ Hull-Strominger system. These manifolds arise as total spaces of principal $T^3$ (orbi)bundles over singular K3 surfaces. Our construction is based on the choice of three divisors on a singular K3 surface that are primitive with respect to a particular K\"ahlermetric. The stable bundle is obtained via an adaptation of the Serre construction to the singular setting.

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Anna Fino, Gueo Grantcharov, Jose Medel. 2026-01-28. New Solutions to the $G_2$ Hull-Strominger System via torus fibrations over $K3$ orbifolds. https://arxiv.org/abs/2601.20813

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