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arXiv · 2507.02441

Groups of Projectivities in Spherical Buildings of Non-Simply Laced Type

Sira Busch·Hendrik Van Maldeghem
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Abstract

In this article we describe the general and special projectivity groups for all irreducible residues of all thick, irreducible, spherical buildings of type $ \mathsf{B_{n}}$, $ \mathsf{C_{n}}$ and $\mathsf{F_4}$, and rank at least 3. This determines the exact structure and action of Levi subgroups of parabolic subgroups of groups of Lie type related to those buildings.

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Sira Busch, Hendrik Van Maldeghem. 2025-07-03. Groups of Projectivities in Spherical Buildings of Non-Simply Laced Type. https://arxiv.org/abs/2507.02441

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