Generalized Hexagons as Amalgamations of Generalized Quadrangles
โ Scribed by H. Van Maldeghem; I. Bloemen
- Publisher
- Elsevier Science
- Year
- 1993
- Tongue
- English
- Weight
- 478 KB
- Volume
- 14
- Category
- Article
- ISSN
- 0195-6698
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โฆ Synopsis
We define the notion of regular point (p) in a generalized hexagon and show how a derived geometry at such a point can be defined. We motivate this by proving that, for finite generalized hexagons of order ((s, t)), this derivation is a generalized quadrangle iff (s=t). Moreover, if the generalized hexagon has also a regular line incident with (p), then one can amalgamate the two corresponding generalized quadrangles and in this way reconstruct the generalized hexagon. The small Moufang hexagons of order (3^{h}), for small (h), are characterized in this manner.
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