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arXiv · 2606.10443

Geometry of gravitational instantons

Mingyang Li·Song Sun
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Abstract

We survey recent progress in the classification of hyperk\"ahler and Hermitian gravitational instantons (i.e., complete noncompact 4 dimensional Ricci-flat manifolds with quadratic curvature decay), as well as the construction of non-Hermitian gravitational instantons via harmonic maps. We also present a list of open questions related to gravitational instantons.

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Mingyang Li, Song Sun. 2026-06-09. Geometry of gravitational instantons. https://arxiv.org/abs/2606.10443

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