Abstract
This paper is concerned with constructing caps embedded in line Grassmannians. In particular, we construct a cap of size q3 +2q2+1 embedded in the Klein quadric of PG(5,q) for even q, and show that any cap maximally embedded in the Klein quadric which is larger than this one must have size equal to the theoretical upper bound, namely q3+2q2+q+2. It is not known if caps achieving this upper bound exist for even q > 2.
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Ebert, G.L., Metsch, K. & Szönyi, T. Caps Embedded in Grassmannians. Geometriae Dedicata 70, 181–196 (1998). https://doi.org/10.1023/A:1004912020519
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DOI: https://doi.org/10.1023/A:1004912020519