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arXiv · 2610.23711

Finite Cyclic Fundamental Groups and Exotic Universal Covers from the Cartwright--Steger Surface

Anar Akhmedov·B. Doug Park·Sümeyra Sakallı·Sai-Kee Yeung
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Abstract

We use a particular nodal curve on the Cartwright-Steger surface to construct minimal symplectic four-manifolds with arbitrary nontrivial finite cyclic fundamental group and fixed topological invariants $(e,σ,χ_h,c_1^2)=(43,1,11,89)$. Using these symplectic four-manifolds as building blocks, we construct a symplectic 4-manifold that is homeomorphic to $(22m-1)\mathbb{CP}^2\#(21m-1)\overline{\mathbb{CP}}^{\,2}$ for any integer $m\geq 2$.

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Anar Akhmedov, B. Doug Park, Sümeyra Sakallı, Sai-Kee Yeung. 2026-10-16. Finite Cyclic Fundamental Groups and Exotic Universal Covers from the Cartwright--Steger Surface. https://arxiv.org/abs/2610.23711

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