Intransitive geometries

Ralf Köhl; Hendrik Van Maldeghem

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arXiv · 0708.1583

Intransitive geometries

Ralf Köhl·Hendrik Van Maldeghem

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Abstract

A lemma of Tits establishes a connection between the simple connectivity of an incidence geometry and the universal completion of an amalgam induced by a sufficiently transitive group of automorphisms of that geometry. In the present paper, we generalize this lemma to intransitive geometries, thus opening the door for numerous applications. We treat ourselves some amalgams related to intransitive actions of finite orthogonal groups, as a first class of examples.

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Ralf Köhl, Hendrik Van Maldeghem. 2007-08-11. Intransitive geometries. https://arxiv.org/abs/0708.1583

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