Corrigendum to the paper "Ovoidal packings of PG(3, q) for even q"

نویسندگان

  • Bhaskar Bagchi
  • N. S. Narasimha Sastry
چکیده

We show that any set of n pairwise disjoint ovals in a finite projective plane of even order has a unique common tangent. As a consequence, any set of q+1 pairwise disjoint ovoids in PG(3, q), q even, has exactly q2+1 common tangent lines, constituting a regular spread. Also, if q−1 ovoids in PG(3, q) intersect pairwise exactly in two given points x ̸= y and share two tangent planes πx, πy at these two points, then these ovoids share exactly (q + 1)2 common tangent lines, and they consist of the transversals to the pair xy, πx ∩ πy of skew lines. There is a similar (but more complicated) result for the common tangent lines to q ovoids in PG(3, q) which are mutually tangent at a common point and share a common tangent plane through this point. It is also shown that the common tangent lines to any pair of disjoint ovoids of PG(3, q), q even, form a regular spread.

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عنوان ژورنال:
  • Discrete Mathematics

دوره 341  شماره 

صفحات  -

تاریخ انتشار 2018