Closure of Steinberg fibers and affine Deligne-Lusztig varieties
@article{He2010ClosureOS, title={Closure of Steinberg fibers and affine Deligne-Lusztig varieties}, author={Xuhua He}, journal={arXiv: Representation Theory}, year={2010} }
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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