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arXiv · 1707.07955

Signature morphisms from the Cremona group over a non-closed field

Stéphane Lamy·Susanna Zimmermann
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Abstract

We prove that the plane Cremona group over a perfect field with at least one Galois extension of degree 8 is a non-trivial amalgam, and that it admits a surjective morphism to a free product of groups of order two.

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Stéphane Lamy, Susanna Zimmermann. 2018-11-29. Signature morphisms from the Cremona group over a non-closed field. https://doi.org/10.4171/jems%2F983

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