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arXiv · 1003.0238

Closure of Steinberg fibers and affine Deligne-Lusztig varieties

Abstract

We discuss some connections between the closure $\bar F$ of a Steinberg fiber in the wonderful compactification of an adjoint group and the affine Deligne-Lusztig varieties $X_w(1)$ in the affine flag variety. Among other things, we describe the emptiness/nonemptiness pattern of $X_w(1)$ if the translation part of $w$ is quasi-regular. As a by-product, we give a new proof of the explicit description of $\bar F$, first obtained in \cite{H1}.

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BibTeXRIS

Xuhua He. 2010-03-01. Closure of Steinberg fibers and affine Deligne-Lusztig varieties. https://arxiv.org/abs/1003.0238

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