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arXiv · 2006.03516

On the little Weyl group of a real spherical space

Job J. Kuit·Eitan Sayag
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Abstract

In the present paper we further the study of the compression cone of a real spherical homogeneous space $Z=G/H$. In particular we provide a geometric construction of the little Weyl group of $Z$ introduced recently by Knop and Kr\"otz. Our technique is based on a fine analysis of limits of conjugates of the subalgebra $\mathrm{Lie}(H)$ along one-parameter subgroups in the Grassmannian of subspaces of $\mathrm{Lie}(G)$. The little Weyl group is obtained as a finite reflection group generated by the reflections in the walls of the compression cone.

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Job J. Kuit, Eitan Sayag. 2020-06-05. On the little Weyl group of a real spherical space. https://arxiv.org/abs/2006.03516

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