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arXiv · 0909.3211

Ree geometries

Fabienne Haot·Koen Struyve·Hendrik Van Maldeghem
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Abstract

We introduce a rank 3 geometry for any Ree group over a not necessarily perfect field and show that its full collineation group is the automorphism group of the corresponding Ree group. A similar result holds for two rank 2 geometries obtained as a truncation of this rank 3 geometry. As an application, we show that a polarity in any Moufang generalized hexagon is unambiguously determined by its set of absolute points, or equivalently, its set of absolute lines.

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Fabienne Haot, Koen Struyve, Hendrik Van Maldeghem. 2009-09-17. Ree geometries. https://arxiv.org/abs/0909.3211

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