Small covers as pullbacks from the simplex

Suyoung Choi; Hyeontae Jang; Younghan Yoon

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arXiv · 2604.13437

Small covers as pullbacks from the simplex

Suyoung Choi·Hyeontae Jang·Younghan Yoon

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Abstract

We introduce and study small covers that are pullbacks from the simplex, extending pullbacks from the linear model. Our main result gives several equivalent characterizations of this class, including torsion-freeness of odd-degree integral cohomology, vanishing of the first Steenrod square on even-degree mod $2$ cohomology, and relations among integral and mod $2$ Betti numbers.

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Suyoung Choi, Hyeontae Jang, Younghan Yoon. 2026-04-15. Small covers as pullbacks from the simplex. https://arxiv.org/abs/2604.13437

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