## Elliptic elements in a Weyl group: a homogeneity property

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**16**(2012), 127-151 Request permission

## Abstract:

Let $G$ be a reductive group over an algebraically closed field whose characteristic is not a bad prime for $G$. Let $w$ be an elliptic element of the Weyl group which has minimum length in its conjugacy class. We show that there exists a unique unipotent class $X$ in $G$ such that the following holds: if $V$ is the variety of pairs $(g,B)$ where $g\in X$ and $B$ is a Borel subgroup such that $B,gBg^{-1}$ are in relative position $w$, then $V$ is a homogeneous $G$-space.## References

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## Additional Information

**G. Lusztig**- Affiliation: Department of Mathematics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
- MR Author ID: 117100
- Received by editor(s): January 13, 2011
- Received by editor(s) in revised form: June 17, 2011
- Published electronically: February 20, 2012
- Additional Notes: Supported in part by the National Science Foundation
- © Copyright 2012
American Mathematical Society

The copyright for this article reverts to public domain 28 years after publication. - Journal: Represent. Theory
**16**(2012), 127-151 - MSC (2010): Primary 20G99
- DOI: https://doi.org/10.1090/S1088-4165-2012-00409-5
- MathSciNet review: 2888173