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arXiv · 2505.10826

Free boundary minimal annuli in $S^2_+\times S^1$

Pak Tung Ho·Juncheol Pyo·Keomkyo Seo
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Abstract

Let $M$ be a compact 3-dimensional Riemannian manifold with nonnegative Ricci curvature and a nonempty boundary $\partial M$. Fraser and Li \cite{Fraser&Li} established a compactness theorem for the space of compact, properly embedded minimal surfaces of fixed topological type in $M$ with a free boundary on $\partial M$, assuming that $\partial M$ is strictly convex with respect to the inward unit normal. In this paper, we show that the strict convexity condition on $\partial M$ cannot be relaxed.

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Pak Tung Ho, Juncheol Pyo, Keomkyo Seo. 2025-05-16. Free boundary minimal annuli in $S^2_+\times S^1$. https://doi.org/10.1017/s001309152510076x

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