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arXiv · 1706.01356

On the rationality problem for quadric bundles

Stefan Schreieder
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Abstract

We classify all positive integers n and r such that (stably) non-rational complex r-fold quadric bundles over rational n-folds exist. We show in particular that for any n and r, a wide class of smooth r-fold quadric bundles over projective n-space are not stably rational if r lies in the interval from $2^{n-1}-1$ to $2^{n}-2$. In our proofs we introduce a generalization of the specialization method of Voisin and Colliot-Th\'el\`ene--Pirutka which avoids universally $CH_0$-trivial resolutions of singularities.

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Stefan Schreieder. 2017-06-05. On the rationality problem for quadric bundles. https://doi.org/10.1215/00127094-2018-0041

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