A Note on Null Designs of Dual Polar Spaces
نویسنده
چکیده
Null designs on the poset of dual polar spaces are considered. A poset of dual polar spaces is the set of isotropic subspaces of a finite vector space equipped with a nondegenerate bilinear form, ordered by inclusion. We show that the minimum number of isotropic subspaces to construct a nonzero null t-design is Qt i=0(1 + q ) for the types BN , DN , whereas for the case of type CN , more isotropic subspaces are needed.
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