A NOTE ON NULL DESIGNS OF DUAL POLAR SPACES

Title & Authors
A NOTE ON NULL DESIGNS OF DUAL POLAR SPACES
CHO, SOO-JIN;

Abstract
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 $\small{{\prod}^{t}_{i=0}(1+q^{i})}$ for the types $\small{B_N,\;D_N}$, whereas for the case of type $\small{C_N}$, more isotropic subspaces are needed.
Keywords
null designs;minimal null designs;dual polar spaces;
Language
English
Cited by
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