On Near Hexagons and Spreads of Generalized Quadrangles
Bart De Bruyn
DOI: 10.1023/A:1008709716107
Abstract
The glueing-construction described in this paper makes use of two generalized quadrangles with a spread in each of them and yields a partial linear space with special properties. We study the conditions under which glueing will give a near hexagon. These near hexagons satisfy the nice property that every two points at distance 2 are contained in a quad. We characterize the class of the glued near hexagons and give examples, some of which are new near hexagons.
Pages: 211–226
Keywords: spread; generalized quadrangle; near polygon
Full Text: PDF
References
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2. A.E. Brouwer, A.M. Cohen, J.I. Hall, and H.A. Wilbrink, “Near polygons and Fischer spaces,” Geom. Dedicata 49 (1994), 349-368.
3. A.E. Brouwer and H.A. Wilbrink, “The structure of near polygons with quads,” Geom. Dedicata 14 (1983), 145-176.
4. B. De Bruyn and F. De Clerck, “On linear representations of near hexagons,” European J. Combin. 20 (1999), 45-60.
5. M. Hall, Jr., “Affine generalized quadrilaterals,” Studies in Pure Mathematics, Academic Press, London, 1971, pp. 113-116.
6. S.E. Payne and J.A. Thas, Finite Generalized Quadrangles, Pitman, Boston,
1984. Research Notes in Mathematics, vol. 110.
7. S.A. Shad and E.E. Shult, “The near n-gon geometries,” Unpublished, 1979.
8. E.E. Shult and A. Yanushka, “Near n-gons and line systems,” Geom. Dedicata 9 (1980), 1-72.