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On the stable rationality of $X/G$

Amnon Neeman
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Abstract

Let $G$ be a connected, reductive algeraic group whose Dynkin diagram contains no components of type $G_2,$ $F_4,$ $E_6,$ $E_7$ or $E_8.$ That is, all the components are of classical type. Suppose $X$ is an affine variety, and suppose $G$ acts freely on $X.$ Then $X$ and $X/G$ are stably birationally equivalent.

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Amnon Neeman. 1992-12-14. On the stable rationality of $X/G$. https://arxiv.org/abs/alg-geom/9212002

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