A pr 2 00 6 A Quasi Curtis - Tits - Phan theorem for the symplectic group
نویسنده
چکیده
We obtain the symplectic group as an amalgam of low rank subgroups akin to Levi components. We do this by having the group act flag-transitively on a new type of geometry and applying Tits’ lemma. This provides a new way of recognizing the symplectic groups from a small collection of small subgroups.
منابع مشابه
A Quasi Curtis-Tits-Phan theorem for the symplectic group
We obtain the symplectic group Sp(V ) as the universal completion of an amalgam of low rank subgroups akin to Levi components. We let Sp(V ) act flag-transitively on the geometry of maximal rank subspaces of V . We show that this geometry and its rank ≥ 3 residues are simply connected with few exceptions. The main exceptional residue is described in some detail. The amalgamation result is then ...
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