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arXiv · 1511.03591

(Stable) rationality is not deformation invariant

Claire Voisin
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Abstract

We prove the existence of a family $\mathcal{X}\rightarrow B$ of smooth projective fourfolds, such that the very general fiber $\mathcal{X}_t$ is not stably rational (a fortiori not rational), but some special fibers $\mathcal{X}_t$ are rational (a fortiori stably rational).

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Claire Voisin. 2015-11-11. (Stable) rationality is not deformation invariant. https://arxiv.org/abs/1511.03591

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