کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
9515377 1343450 2005 14 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Tangential Tallini sets in finite Grassmannians of lines
موضوعات مرتبط
مهندسی و علوم پایه ریاضیات ریاضیات گسسته و ترکیبات
پیش نمایش صفحه اول مقاله
Tangential Tallini sets in finite Grassmannians of lines
چکیده انگلیسی
A Tallini set in a semilinear space is a set B of points, such that each line not contained in B intersects B in at most two points. In this paper, the following notion of a tangential Tallini set in the Grassmannian Γn,1,q, q odd, is investigated: a Tallini set is called tangential when it meets every ruled plane (i.e. the set of lines contained in a plane of PG(n,q)) in either q+1 or q2+q+1 elements. A Tallini set QB in PG(n,q) can be associated with each tangential Tallini set B in Γn,1,q. Each ℓ∈B is a line of PG(n,q) intersecting QB in either 0, or 1, or q+1 points; when n≠4 and B is covered by (n-2)-dimensional projective subspaces of Γn,1,q the first case does not occur. If B is a tangential Tallini set in Γn,1,q covered by (n-2)-dimensional subspaces, any of which is in PG(n,q) the set of all lines through a point and in a hyperplane, then either QB is a quadric, and B is the set of all lines contained in, or tangent to, QB, or B is a linear complex.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Combinatorial Theory, Series A - Volume 109, Issue 2, February 2005, Pages 189-202
نویسندگان
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