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arXiv · 2312.05197

On a Theorem by Lin and Shinder through the Lens of Median Geometry

Anthony Genevois·Anne Lonjou·Christian Urech
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Abstract

Recently, Lin and Shinder constructed non-trivial homomorphisms from Cremona groups of rank >2 to \mathbb{Z} using motivic techniques. In this short note we propose an alternative perspective from median geometry on their theorem.

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Anthony Genevois, Anne Lonjou, Christian Urech. 2023-12-08. On a Theorem by Lin and Shinder through the Lens of Median Geometry. https://arxiv.org/abs/2312.05197

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