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arXiv · 2603.29306

Moduli spaces of contact instantons on Sasakian 5-manifolds with transverse Calabi-Yau structures and orbifold K3 surfaces

Tomohiro Arai·Kurando Baba
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Abstract

We study anti-self-dual contact instantons on 5-dimensional Sasakian manifolds with transverse Calabi-Yau structures. In this case, the leaf space is a Calabi-Yau orbifold, and the moduli space of irreducible anti-self-dual contact instantons is a hyperkahler manifold. Using the singularity data of the leaf spaces, we prove that the transverse Levi-Civita connection gives an irreducible anti-self-dual contact instanton in the case when the leaf space is one of the 95 orbifold $K3$ surfaces classified by Reid. Moreover, we compute explicitly the complex dimension of the corresponding moduli spaces in all 95 cases.

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Tomohiro Arai, Kurando Baba. 2026-03-31. Moduli spaces of contact instantons on Sasakian 5-manifolds with transverse Calabi-Yau structures and orbifold K3 surfaces. https://arxiv.org/abs/2603.29306

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