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Unitals which meet Baer subplanes in 1 moduloq points

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Abstract

We prove that a parabolic unitalU in a translation plane π of orderq 2 with kernel containing GF(q) is a Buekenhout-Metz unital if and only if certain Baer subplanes containing the translation line of π meetU in 1 moduloq points. As a corollary we show that a unital 16-03 in PG(2,q 2) is classical if and only if it meets each Baer subplane of PG(2,q 2) in 1 moduloq points.

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Authors and Affiliations

  1. Department of Pure Mathematics, The University of Adelaide, 5005, Australia

    S. G. Barwick & Christine M. O'Keefe

  2. Department of Pure Mathematics and Computer Algebra, University of Gent, Galglaan 2, B-9000, Gent, Belgium

    L. Storme

Authors
  1. S. G. Barwick
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  2. Christine M. O'Keefe
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  3. L. Storme
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Barwick, S.G., O'Keefe, C.M. & Storme, L. Unitals which meet Baer subplanes in 1 moduloq points. J Geom 68, 16–22 (2000). https://doi.org/10.1007/BF01221057

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  • DOI: https://doi.org/10.1007/BF01221057

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