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arXiv · 2607.14055

Open surfaces with a triangle at infinity

Dmitriy Chunaev·Alexander Perepechko·Daniil Shunin
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Abstract

A triangle surface is an open algebraic surface completed by a triangle of contractible $(-1)$-curves. We establish a combinatorial description of their completions. We also show that affine triangle surfaces are exactly cubic surfaces of Markov type. Explicit description of their automorphism groups is provided.

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Dmitriy Chunaev, Alexander Perepechko, Daniil Shunin. 2026-07-15. Open surfaces with a triangle at infinity. https://arxiv.org/abs/2607.14055

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