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arXiv · 2002.11551

Birational sheets in reductive groups

Filippo Ambrosio
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Abstract

We define the group analogue of birational sheets, a construction performed by Losev for reductive Lie algebras. For G semisimple simply connected, we describe birational sheets in terms of Lusztig-Spaltenstein induction and we prove that they form a partition of G, and that they are unibranch varieties with smooth normalization by means of a local study.

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BibTeXRIS

Filippo Ambrosio. 2020-02-26. Birational sheets in reductive groups. https://doi.org/10.1007/s00209-020-02597-3

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