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arXiv · 0910.1783

Five embeddings of one simple group

Ivan Cheltsov·Constantin Shramov
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Abstract

We propose a new method to study birational maps between Fano varieties based on multiplier ideal sheaves. Using this method, we prove equivariant birational rigidity of four Fano threefolds acted on by the group A6. As an application, we obtain that the Cremona group of rank 3 has at least five non-conjugate subgroups isomorphic to A6.

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Ivan Cheltsov, Constantin Shramov. 2011-12-07. Five embeddings of one simple group. https://arxiv.org/abs/0910.1783

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