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arXiv · 1701.08372

Stable rationality of del Pezzo fibrations of low degree over projective spaces

Igor Krylov·Takuzo Okada
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Abstract

The main aim of this article is to show that a very general 3-dimensional del Pezzo fibration of degree 1,2,3 is not stably rational except for a del Pezzo fibration of degree 3 belonging to explicitly described 2 families. Higher dimensional generalizations are also discussed and we prove that a very general del Pezzo fibration of degree 1,2,3 defined over the projective space is not stably rational provided that the anticanonical divisor is not ample.

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Igor Krylov, Takuzo Okada. 2017-01-29. Stable rationality of del Pezzo fibrations of low degree over projective spaces. https://arxiv.org/abs/1701.08372

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