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arXiv · 2311.09751

Folding median graphs

Anthony Genevois·Yassine Guerch·Romain Tessera
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Abstract

Extending Stallings' foldings of trees, we show in this article that every parallel-preserving map between median graphs factors as an isometric embedding through a sequence of elementary transformations which we call foldings and swellings. This new construction proposes a unified point of view on Beeker and Lazarovich's work on folding pocsets and on Ben-Zvi, Kropholler, and Lyman's work on folding nonpositively curved cube complexes.

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Anthony Genevois, Yassine Guerch, Romain Tessera. 2023-11-16. Folding median graphs. https://arxiv.org/abs/2311.09751

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