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arXiv · 1906.05265

Relations in the Cremona group over perfect fields

Julia Schneider
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Abstract

For perfect fields $k$ satisfying $[\bar k:k]>2$, we construct new normal subgroups of the plane Cremona group and provide an elementary proof of its non-simplicity, following the melody of the recent proof by Blanc, Lamy and Zimmermann that the Cremona group of rank $n$ over (subfields of) the complex numbers is not simple for $n\geq3$.

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Julia Schneider. 2019-06-12. Relations in the Cremona group over perfect fields. https://arxiv.org/abs/1906.05265

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