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arXiv · 1704.01807

Degenerations of Gushel-Mukai fourfolds, with a view towards irrationality proofs

Christian Böhning·Hans-Christian Graf von Bothmer
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Abstract

We study a certain class of degenerations of Gushel-Mukai fourfolds as conic bundles, which we call tame degenerations and which are natural if one wants to prove that very general Gushel-Mukai fourfolds are irrational using the degeneration method due to Voisin, Colliot-Th\'{e}l\`{e}ne-Pirutka, Totaro et al. However, we prove that no such tame degenerations do exist.

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Christian Böhning, Hans-Christian Graf von Bothmer. 2017-04-06. Degenerations of Gushel-Mukai fourfolds, with a view towards irrationality proofs. https://doi.org/10.1007/s40879-018-0227-z

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